可制造性范文
可制造性范文（精选10篇）
可制造性 第1篇
IC工业的发展使得设计工程师不断面临新技术、新挑战。为了满足设计越来越苛刻的要求,设计人员需要考虑的方面也成倍增加从性能、面积到功耗、可测性等。然而当工艺发展到90 nm以下后,一个更加难以测量和控制的因素凸显了出来:良率。
造成良率损失的原因是由于越来越复杂的制造工艺。它大致可分为3个方面:随机缺陷[1],与图形相关的制造缺陷[2],可光刻性的缺陷[3]。其中,后两项构成了当今可制造性设计(Design For Manufacturability,DFM)的主要考虑要素[4]。
为了能使集成电路从设计阶段就将良率考虑进去,对标准单元的可制造性分级显得尤为迫切和重要。本文对设计规则和工艺参数对电路可制造性的影响进行分析,从而对标准单元进行分级。
2 标准单元可制造性分级的必要性
IC设计发展到今天,对标准单元的各种度量(Metrics)已比较成熟,综合工具能够利用这些度量,来综合出设计所需的电路。面积是最容易被精确测量出的参量,一般用平方微米来表示一个单元的大小。性能一般用延时纳秒表示。现在延时一般用几个工艺情况(process corners,e.g.fast,slow,typical)来描述,这样存在不准确的情况。更为严重问题是在深亚微米设计下,连线延时变成了延时的主因[5]。传统的连线延时模型(Wire Load Model)已经不能满足精度的要求,综合工具已经开始更多地把布局信息考虑进去。功耗通常包括动态功耗和漏电功耗这2个部分。但总的来说,这些参量都能够用Spice较好的估算出来。
在理想状况下,可制造性也因该与功耗、性能、面积一样,被综合工具所用,但目前要实现还有一定的难度。首先,可制造性并不像其他度量一样有一个被业界广泛认可的标准,良率的范围也很难被统一地界定。其次,虽然一些研究对标准单元的可制造性进行了优化[6,7],使得良率更高,但要求性能无限制提升是不现实的。因为在不断提高良率的同时,也对掩膜提出了更高的要求,这样会使成本大幅提高,大规模集成也就失去了意义。再有,并不是版图的每一个部分都需要被修改以提高良率,而只需要对某些关键的区域进行修改,便可使整体良率得到提升。亦即只需对关键区域的良率提出更高的要求。从上述几点看来,对版图的可制造性分级就显得十分必要和迫切。
3 考虑工艺变化的标准单元可制造性分级
标准单元的可制造性分级大致分为2种:一种是基于规则(Design Rule)的[8],一种是基于模型的[9]。前者是根据Foundry在长期生产中积累的数据,建立起的比较成熟的规则。它的优点是减少了掩膜制造的复杂度(虽然现在Design Rule中的DFM Rule也在不断增加),并且和传统IC设计流程完全一致,降低了对设计者的要求。缺点是精度不高,且可控性不强即不能对特定的区域指定特定的良率。另一种是基于模型的方法。它是对掩膜进行光刻、CMP等仿真,将得到的图形与版图比对,然后迭代修改直至图形失真达到可接受的程度。它的优点是预测更精确,缺点在于计算及数据量太大,且需要修改流程,对设计者要求更高。此外,实施全芯片仿真迭代并收敛是很困难的。
综合考虑上述可制造性分级的优缺点,本文提出了考虑工艺变化的标准单元可制造性分级。这种方法以DFM rule对版图的约束为基础,综合考量工艺参数变化对其造成的影响,用加权的方法对其分级。这种分级方法比基于规则的分级方法精度更高,可控性更强,而数据量增加有限。更为关键的是,这种分级方法有统一性和标准性,所以它适用于不同的工艺、不同的Foundry。如果能够被业界接受,并被广泛使用,那么可制造性会成为像Spice这一黄金标准(Golden Standard)中的其他参量一样,更好地被设计者估算和运用。
本文分级方法分为设计规则影响因子和工艺参数影响因子2部分,如表1所示。
最终,可制造性指数=∑设计规则影响因子工艺参数影响因子。
首先是设计规则影响因子,它包含了2部分:权重因子和影响因子函数。各主流代工厂如台积电(TSMC)、富士通(Fujitsu)、中芯国际(SMIC)等在工艺达到90 nm或65 nm时,都对自己的标准单元库提出了DFM规则。所谓DFM规则是指在设计规则(Required Design Rule)的基础上,代工厂给出能使良率更高的推荐规则(Recommended Rule)。各代工厂的推荐规则类似但各有不同。本文的分级方法包含了所有的DFM规则,并对DFM规则加以权重,使得对可制造性影响更大的的因素凸现出来。要保证undefined权重因子i=1,这样才会使得分级具有统一性和标准性。此外,如果Foundry A没有Foundry B 的某个DFM规则,只需把权重因子赋为0即可消除此规则。另一部分是影响因子函数,它对最小间距和推荐规则进行了细分,这样使得可制造性精度更高。函数如下所示:在设计规则要求以下是不允许的,因此为0。在设计规则和推荐规则之间可由Foundry 给出递增函数。在大于推荐规则的情况下,y值恒为1。
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其次用工艺参数因子把工艺变化考虑进去。对于同一个DFM规则,每个Foundry的工艺各有不同。即便对于同一Foundry,在工艺实现时也会随着工艺参数变化而变化。以多晶(POLY)间距这一规则为例,即便采用相同的版图规则其间距为一恒定值,但由于制造工艺参数:离焦(Cefocus)不一样,也会使得实际制造出的图形的关键尺寸(Critical Dimension)有很大的变化。基于模型[10]:undefined可得到可光刻性数值,在此也将其转化成权重因子。同时,出现这几种散焦的概率不同,在此用发生概率因子加以区分。发生概率与影响因子乘积的和,便可以体现工艺参数对该规则的影响,这使得分级更精确,可控性更强。
4 可制造性分级举例及分析
本文旨在方法学的探究,因此只取2个DFM规则为例。这种简化在原理上并无差别,因此不失其一般性。以90 nm工艺实例化表1,得表2中各参数。
设计规则影响函数如图1所示。
假设有2个版图,基本图形和参数如图2,表3所示。根据DFM要求只需取多晶层和有源层。
根据表2得到版图1和版图2的可制造性指数分别为0.047 3和0.22。可见版图2的可制造性要远高于版图1。图3为光刻模拟结果,它印证了可自造性指数的有效性。
5 结 语
在可制造性越来越重要的今天,让设计者对电路的可制造性进行量化处理显得越来越迫切。本文提供了一种对标准单元进行可制造性分级的解决方案。这种设计方法考虑了设计和工艺双重因素,使得分级精度更高,可控性更强,具有统一性和标准性。
本文所用方法需提供给各代工厂一个全面的DFM规则标准,让其自行选择所需要的规则,提供这样全面的标准并不容易。此外标准要考虑光刻性、化学机械抛光等因素,因此完成这样的标准还有很多工作要做。
摘要：随着制造工艺尺寸的缩小,可制造性不只是工厂需要关注的问题,更是设计者需要考虑的重点,从而提高良率和版图面积的利用率。为了使设计者更好地理解和控制可制造性,对标准单元的可制造性分级显得尤为重要。用加权重的方法对标准单元进行可制造性分级,该方法不但包含可制造性规则对版图的约束,还创新性地把工艺参数变化对其造成的影响考虑了进去。用一套简化的可制造性规则和版图来演示此种分级方法的实现,并用模拟结果验证了它的有效性。该分级方法具有统一性和标准性,可以被广泛采用。
关键词：可制造性,标准单元,权重,光刻模拟
参考文献
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美研发可快速制造烃类燃料的反应器 第2篇
这个过程类似于植物的生长过程，植物为维持生长也会使用来自太阳的能源将二氧化碳转变为糖基聚合物和芳香烃化合物。这些化合物中包含的氧被去除后即可转变为燃料，其方式或是通过在地下历经数千年的降解以形成化石燃料，或通过一种更加迅速的分解、发酵和氢化过程来产生生物燃料。
然而，利用植物将太阳光转化为化学燃料并非最有效的办法，制造出实用的太阳能燃料还有很长的路要走。因此，研究人员正在寻找方法，希望可以在不依赖植物的生长和分解等中间步骤的情况下用太阳光将二氧化碳转变为烃类燃料。
现在，美国加州理工学院的威廉姆•陈和同事演示了一种可能的反应器设计。在这种反应器中，被聚集在一起的太阳光能将氧化铈——稀土金属铈的氧化物加热到足够高的温度，将氧原子从它的晶格中摇散并使之脱落；接着，该材料可以很容易地从水或二氧化碳中剥夺其氧原子以取代自己失去的氧原子，从而得到氢气或一氧化碳；再使用额外的催化剂，可以将氢气和一氧化碳结合在一起生成燃料。
按照设计，集聚的太阳光通过一个窗孔进入该太阳腔室反应器，光线在腔室內可反射多次，以确保反应器能捕捉到足够多的入射太阳能。圆柱形的氧化铈片同样被置于腔室内，并经受数百次的热—冷循环以诱导燃料的产生。（刘霞）
可制造性 第3篇
层次分析法(analytic hierarchy process, AHP),是美国运筹学家匹兹堡大学教授萨迪(T.L.Saaty)于20世纪70年代中期提出来的一种实用多目标决策分析方法。它将定性和定量指标统一在一个模型中,既能进行定量分析,又能进行定性的功能评价。AHP方法具有以下优点:1)系统性:层次分析法把研究对象作为一个系统,按照分解、比较判断、综合的思维方式进行决策;2)实用性:层次分析法把定性和定量方法结合起来,能处理许多用传统的最优化技术无法着手的实际问题。
1 AHP法数学模型
AHP方法包括以下4个步骤:1)建立递阶层次结构模型;2)构造出各层次中的所有判断矩阵;3)层次单排序及一致性检验;4)层次总排序及一致性检验。
其具体数学模型可以描述为:
a) 建立递阶层次结构模型:将各方案的评价因素按其对目标的属性分为若干个分系统,建立层次结构模型如图1:
b) 构造出各层次中的所有判断矩阵A:
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引用数字1～9及其倒数作为标度来确定aij的值。下面列出了1～9标度的含义:
1表示两个因素相比,具有相同重要性;
3表示两个因素相比,前者比后者稍重要;
5表示两个因素相比,前者比后者明显重要;
7表示两个因素相比,前者比后者强烈重要;
9表示两个因素相比,前者比后者极端重要;
2,4,6,8表示上述相邻判断的中间值;
若因素i与因素j的重要性之比为aij,那么因素j与因素i重要性之比为undefined。
c) 进行层次单排序及一致性检验:
判断矩阵A对应于最大特征值λmax的特征向量W,经归一化后即为同一层次相应因素对于上一层次某因素相对重要性的排序权值。
对判断矩阵的一致性检验的步骤如下:
1) 计算一致性指标CI:
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2) 查找相应的平均随机一致性指标RI。对n=1, , 9,萨迪给出了RI的值,如表1所示:
3) 计算一致性比例CR:
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当CR<0.10时,认为判断矩阵的一致性是可以接受的,否则应对判断矩阵作适当修正。
d) 进行层次总排序及一致性检验:
设上一层次(A层)包含A1, , Am共m个因素,它们的层次总排序权重分别为a1, , am。又设其后的下一层次(B层)包含n个因素B1, , Bn,它们关于Aj的层次单排序权重分别为b1j, , bnj(当Bi与Aj无关联时,bij=0)。现求B层中各因素关于总目标的权重,即求B层各因素的层次总排序权重b1, , bn,计算按表2所示方式进行,即undefined。
设B层中与Aj相关的因素的成对比较判断矩阵在单排序中经一致性检验,求得单排序一致性指标为CI(j),(j=1,,m),相应的平均随机一致性指标为RI(j)(CI(j), RI(j)已在层次单排序时求得),则B层总排序随机一致性比例为:
undefined
当CR<0.10时,认为层次总排序结果具有较满意的一致性并接受该分析结果。
2 零件可制造性评价实例分析
下面是减速机主轴的三种设计方案(图3),3个零件均可制造,图2(a)圆角过小,图2(b)没有退刀槽,图2(c)过渡圆角适中,且有退刀槽。因此图2(c)的结构性能比图2(a), 图2(b)要好些。对该零件可制造性评价分析如下:
a) 建立递阶层次结构模型:生产实践中零件制造需要评价内容为:1)结构性;2)加工性;3)装配性;4)制造成本;5)市场评价。建立递阶层次结构模型如图3所示。
第二层中的各因素对目标层的影响两两比较结果列于表3。
b) 构造出各层次中的所有判断矩阵
undefined
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c) 层次单排序的权向量和一致性检验:经计算得CI=0.018, RI=1.12, CR=0.016<0.1。
表明A通过了一致性检验。由计算可知B1～B5通过一致性检验。
d) 计算层次总排序权值和一致性检验:由计算得C1,C2,C3对总目标的权值分别为:0.298,0.239,0.461。决策层对总目标得权向量为:{0.298,0.239,0.461}。又CR=0.015<0.1故,层次总排序通过一致性检验。即各方案得权重排序为C3>C1>C2;故方案三最好。
3 结论
这里介绍AHP方法的数学模型并采用此算法对减速机主轴的可制造性进行了评价,从计算结果上看,符合实际情况,证实了方法的可行性。这说明AHP方法在零件可制造性评价方面有着很好的应用前景。
摘要：AHP法是一种实用多目标决策分析方法。介绍了AHP方法模型算法及实现过程,并采用该方法对减速机主轴的可制造性进行了评价。分析结果表明,此方法符合实际情况,证实了在零件可制造性评价方面的可行性。
关键词：可制造性评价,层次分析法,层次结构
参考文献
[1]褚学宁.基于模糊集理论的产品可制造性综合评价[J].计算机集成制造系统,1998(2).
怎样运动可助“性” 第4篇
我去年生了一场大病，在家休息了两个月，期间吃了许多补品。后来身体虽然康复了，却显得很臃肿。肥胖的体型让我对夫妻生活明显冷淡下来，为此老公对我很有意见，我也在一直想办法改变现状。我听朋友说运动能有效助“性”，同时也能减肥，我认为这是个一举两得的好方法，后来我天天早晚都坚持跑步、跳绳，每天运动两个小时以上。半年以后，我的身材苗条了，然而“性”趣却一点也没有增加。请问为什么会这样呢？运动究竟能不能对夫妻生活有所帮助呀？
舒雨解答：
首先肯定一点，就是你朋友的说法没错，长期坚持体育锻炼不但有利于身体健康、预防疾病，的确还能提高人体性唤醒能力，增强性高潮快感。但是需要指出的是：过量密集的锻炼计划将会使人精疲力竭，如果一个人的体力都已经透支，那么就势必会影响夫妻两性生活。而且当过度的锻炼使身体的脂肪含量低于15%时，控制性激情的雌激素就会减少分泌，从而使女性很难提起“性”趣。所以，如果你想通过体育锻炼来提高性生活質量，就一定要控制好运动的尺度。
研究表明，以下几项运动对提高女性的“性”趣有较好的效果：
游泳：采用蛙式姿式最好，长期坚持锻炼，可使腹部肌肉变得结实，在做爱时感觉会更为美好。
骑自行车：这是一项最易于坚持的运动方式，它可以锻炼女性的腿部关节和大腿肌肉。同时，它还有助于你的血液循环系统。
慢跑/散步：对心脏和血液循环系统都有很大的好处，每天保持锻炼30分钟以上，会有利于减肥，并能提升女性的性欲望。
国外“可持续制造”研究述评 第5篇
关键词：可持续制造,制造业,可持续发展,实现路径,评价
制造业是国民经济的支柱产业,是经济社会发展的重要依托。但同时,制造业也造成了世界上绝大部分的资源消耗和废物产生。可持续制造是从可持续性的角度构建的新制造系统范式[1],它通过生产财富和新的服务确保发展和竞争力,应对经济挑战; 通过推动自然资源使用的最小化和最佳管理方法,减少环境影响,应对环境挑战; 通过更新财富和工作质量,推动社会发展,改善生活质量,应对社会挑战。高附加值的、以知识为基础的、有竞争力的可持续制造被视为可持续发展的主要推动力量[2]。2008年金融危机后,世界各国重新重视以制造业为代表的实体经济,美国等发达国家也提出了“再工业化”口号,全球制造业竞争更加激烈。快速实现向可持续制造范式的转型,是许多国家在国际制造业竞争中抢占战略制高点的共同选择。可持续制造研究也因此得到越来越多学者的关注,日益成为一个跨学科研究热点领域。
在Web of Science数据库中,以“SustainableManufacturing”为标题的文献 最早出现 于2000年,2005年后文献数量逐渐增多,到2012年达到高峰。在Academic Research Library、EBSCO、Elsevier、Emerald等数据库中检索2000 ~ 2012年以“Sustainable Manufacturing”为题名 的论文,均可获得数十至百余篇文献。美国电气和电子工程师协会 ( IEEE) 多次举办与可持续制造有关的学术会议。美国国家标准与技术研究院 ( NIST)于2009年举办了“可持续制造: 指标,标准及基础”研讨班[3]。《国际生产研究》、《国际生产经济学》和《生产计划与控制: 操作管理》等期刊都于近年发行了可持续制造特刊。相比之下,国内对可持续制造概念的关注度明显不足。在中国知网中进行检索仅发现10余篇以可持续制造为篇名的论文,且基本都来源于工程技术类期刊,研究视角较为局限。本文在浏览整理国外文献的基础上,从可持续制造的概念内涵出发,把可持续制造的实现路径概括为3个方面,然后对可持续制造评价研究的现状进行总结,最后指出当前可持续制造研究存在的一些不足。希望借他山之石,把国内可持续制造研究的视野扩展到经济、管理、教育等领域,从而对我国制造业的转型升级有所裨益。
1 可持续制造概念辨析
可持续制造概念的提出是可持续发展理论与制造范式转型的现实需求相融合的产物。目前国际上尚没有一致认可的可持续制造定义。根据内涵广度的不同,可对众多学者的界定进行初步梳理。
狭义的界定视可持续制造为一种通过新技术、新工艺,在把材料转化成产品的同时减少负面环境影响的生产方式。如Madu认为“可持续制造指发展和实践把材料转化为产成品的技术,同时减少能源消耗、温室气体排放、废物产生、不可再生或有毒物质的使用”[4]。美国商务部指出,可持续制造是以“使用负面环境影响最小化的材料和加工流程,节省能源和自然资源,对雇员、社会、消费者安全,经济上合理的方式创造制造品”[5]。这两种界定关注的都是产品生命周期中的一个阶段———生产阶段的环境友好性。
广义的界定将可持续制造当作一个系统的减少制造业环境影响,并提供经济绩效的综合策略[6]。Sudarsan Rachuri et al. 认为“可持续制造是一个创造和配送新产品和新服务的系统方法:在产品或服务的整个生命周期使资源使用最小化、减少有害物质、有影响的废物的产生为零、减少温室气体排放”[3]。Marco Garetti et al. 指出,“可持续制造是一套有利于在制造领域实施新方法、新举措、新技术的技术和组织方案,以此应对世界性的资源短缺,减轻环境的超载,使环境友好的产品生命周期成为可能”[7]。这类界定都把可持续制造的研究视角延伸到产品的整个生命周期。
要明确可持续制造的内涵,还需将其与一些相近的概念,如“可持续生产”、“绿色制造”等区分开来。
关于可持续制造与可持续生产的关系,主要有4种不同的看法。第一种把可持续生产看作可持续制造的前身[2],因为可持续生产的概念诞生于1992年,而可持续制造概念的出现较晚,且产生于可持续生产研究的基础之上; 第二种把可持续生产当作可持续制造的一个阶段,声称制造不只是生成商品的生产过程,还应包括所有的工业活动、所有与制造链关联的服务[8]; 第三种把可持续制造视为可持续生产的一个组成部分,按照经济合作与发展组 ( OECD) 的观点,可持续制造就是制造部门的可持续生产[9]; 第四种认为两者同义,可互换使用。
对可持续制造与绿色制造关系的看法则分歧不大,主要有两种观点。一种认为绿色制造是可持续制造的一个组成部分。绿色技术对可持续制造是必须的,但又是不够的[10]; 第二种认为可持续制造是高于绿色制造的制造范式。可持续制造是以创新和6R ( Reduce,Reuse,Recover,Redesign,Remanufacture,Recycle) 为基础的,而绿色制造是以环境友好和3R ( Reduce,Reuse,Recycle) 为基础的,前者对利益相关者的价值比后者更高[11]。
之所以学术界对可持续制造与可持续生产、绿色制造的关系看法不一致,主要还是因为在可持续制造概念的界定上没有形成共识。作为一个区别于可持续生产等相近概念的全新概念,本文认为可持续制造宜取广义的界定,可视之为一个通过多层面的创新来实现系统生态、经济、社会三方面可持续性的制造———服务系统。其内涵主要包括: ( 1) 采用新的生产方式,降低成本,最大化资源能源的生产率;( 2) 构建新的管理模式,减少风险,最小化系统对生态和社会造成的负面影响; ( 3) 培育新的社会环境,形成推动可持续制造的外部氛围。围绕这3个层面的创新,3条可持续制造的实现路径应景而生。
2 可持续制造的工厂路径
早期的可持续制造研究以“环境意识制造”为名,常从微观的视角,关注在工厂内部通过技术创新,实现产品和生产工艺的生态及经济可持续性。后期的研究则加入了对生产过程社会效益的考量。
2. 1 可持续的产品设计
一个产品是否可持续,很大程度上是在早期设计阶段就决定了的,因而设计阶段的干预是减少环境影响、增加产品价值和效用的最有效办法。可用的设计策略有: 面向制造的设计、面向质量的设计、面向装配的设计、面向再制造的设计、面向包装的设计、面向回收或再利用的设计、面向流程的设计等[12]。Ramani et al. 把现有的生态设计工具分成3类: 基于清单的工具 ( 清单是一组用来从环境角度评价产品整个生命周期的条目) 、基于生命周期评价的工具和基于质量功能部署的工具 ( 将环境影响作为一种新的顾客需求引入产品的质量功能部署)[13]。这些设计工具各具特色,也都有自身的局限性,常需联合使用。设计者在设计产品时常需考虑多个目标,而目标之间可能存在冲突,因而需要在目标之间进行权衡,还需要考察每个具体设计的可持续性风险和效益。出于生态可持续性的考虑,在竞争性的设计替代方案中进行选择常以一些评价产品生命周期净环境影响的量化分值为基础[14]。
产品设计最终应关注的不是产品本身,而是人及人的需求。Politecnico Di Torino认为不能把人看作使用者 ( User) ,而要看作是有思想有意识的主体 ( Subject) 。为使用者设计的产品是标准化的,而为主体设计的产品是定制化的。设计师要把“系统设计”和“按部件设计”两种方法整合起来。“系统设计” 不仅要考虑最终产品,还要考虑情境,考虑主体与其他人、与环境的关联; “按部件设计”产生一个新的制造模型———主公司控制全部生产系统,但只生产产品的核心部件,外部供应商由当地生产者担任,由他们按照当地文化背景、资源状况和技术条件生产辅助部件、附件或产品外壳[15]。产品的设计和生产是满足人的需求、提高人类福祉的一种手段。成长环境的不同决定了人们的需求存在差异,而未来的市场需求将更具个性化、异质性特征,这决定了未来的产品将根据各人的需求量身打造。为了在产品定制化的同时控制生产成本,模块化生产成为一种选择。
2. 2 可持续的生产流程
可持续的生产流程应是有弹性、回应性、可靠的,应可减少生产成本,提高产品质量。同时必须: 持续减少废物和与生态不相容的副产品;持续消除对人体健康或环境有害的化学物质或物理因素; 节约能源和材料; 工作空间的设计能最小化化学、物理和人体工程学的危害[2]。
当前研究主要围绕能源和材料这两个关键成分,通过建立流程模型寻找流程优化的关键因子和环节。Jayal & Balaji以金属机械加工为例,建立制造流程模型,对制造流程方案对环境和经济的影响进行高级定量评估,通过调整流程控制参数,结合加工技术进步及高效的操作方法,减少单个材料加工 步骤对环 境的影响[14]。Smith &Ball通过模型化材料流、能量流、废物流,来诊察系统制造流程及相关设施,提出建立材料、能源、废物流程模型的9个步骤和用该模型分析制造系统的16条指导原则,帮助识别和选择改进的机会[16]。通过模拟技术改善制造流程是一种常用而有效的方法,但由于现有模拟技术很少考虑可持续性问题,因此模拟技术本身也要改变,包括改变模拟研究的目标; 改变模拟评价的指标; 改变软件工具、界面标准和参考数据体系等[17]。
一些学者对采用模型优化制造流程的效果进行了实证检验。Harun & Cheng使用流程模型离散事件模拟软件为汽车喷涂店设计颜色重排存储系统,较之传统喷涂流程可减少约53% 的颜色变换次数,增加约50% 的群集率,从而节约了能源,减少了汽车喷涂店的排放[18]。Miller et al.通过对一家小型家具生产公司的3个项目进行案例研究,证明联合使用离散事件模拟和数学优化这两个定量分析工具,可帮助公司建设更清洁的工作单元、减少废物、增加利润,推动可持续制造[19]。
总之,可持续制造的工厂路径关注通过改善产品设计和优化生产流程,在增加企业利润的同时,减少或消除产品本身及其加工流程可能对环境和社会产生的负面影响,其核心是技术进步。Marco Garetti & Marco Taisch认为先进的制造技术应包括采矿、原材料生产、能源生产、制造、运输、配送、维护和回收等过程中的新技术。硬件方面,微电子领域的无线技术、通讯中的植入系统,为节能、提高生产效率,为更好的控制流程和排放、改善安全和维护,为复杂系统的更高级控制,提供了解决办法; 软件方面,数字技术推动了产品设计 和制造系 统设计活 动的实质 进步[8]。ICT ( 信息通信技术) 由于可以增加制造系统的智能化特征[20],进而显著减少其它活动中的二氧化碳排放量[21],其对可持续制造的推动作用得到较多强调。这部分创新的具体举措在可持续生产研究中已有较多探索,从这个角度看,可以把可持续生产当作可持续制造的一个构成部分。
3 可持续制造的系统路径
制造业的可持续发展不仅要求制造企业自身以可持续的方式进行生产,而且涉及其它相关企业的制造或非制造活动。因此必须从纵横向扩展传统制造系统的概念,形成大制造系统观念,并加大系统组织管理模式的创新。对大制造系统组织管理模式的研究,目前以生命周期管理、可持续供应链管理、商业模式转型三者居多。
3. 1 生命周期管理
可持续的系 统方法需 要生命周 期思考。Westkmper et al. 指出,生命周期管理是通过生命周期工程、生命周期评价、产品数据管理、技术支持和生命周期成本核算等手段,保护资源和最大化资源使用效率[22]。Marco Garetti & MarcoTaisch把生命周期管理分为产品生命周期管理和资产生命周期管理两个方面,指出: 产品生命周期管理包括设计可持续的产品、使用集成的产品数据管理系统、开发智能产品3个方面。智能产品可沿着产品生命周期捕获信息,产品生命管理系统可有效收集产品数据,从而满足生命周期管理的需求; 按照资产生命周期管理方法,维护不仅限于资产的使用阶段,而应从获得阶段或概念设计开始。在恰当的地点、时间做出最好的、可预测的维护决策,可最小化设备故障时间,在生命周期中优化制造资产的运转[8]。
可持续制造要求废弃材料尽可能回到供应链,重新用作原材料或能源,从而构成一个“闭环系统”或 “从摇篮到 摇篮”的途 径[20]。但Kaebernick et al. 认为生命末期的决策要基于产品的技术状况、选项的经济可行性这两个条件,必须把这两个条件整合到生命末期成本模型中:PG = PVL - PLCC,PG代表产品收益,PVL代表产品价值,PLCC代表产品生命周期成本,包括生产成本和环境成本[23]。也就是说,对处于生命末期的产品进行回收再利用的前提是产品的残余价值高于回收再利用的成本。而要减少回收再利用的成本,就要开发有效的回收流程和末期产品处置及再利用工具。Morana & Seuring提出了建立闭环供应链从顾客那里回收生命末期产品的计划,但这个计划只是一个志愿系统,因顾客返回产品没有明显的激励而失败[24]。于是Ramani etal. 主张通过给用过的产品定价、设计一个折价或购回程序,给消费者返回末期产品的行为提供经济刺激[13]。
虽然已有学者提出生命周期管理的对象不仅限于产品,但目前的研究主要聚焦于产品,且将重点放在产品的早期设计和末期处理两个方面。产品生命周期其它各阶段的管理、其它对象的生命周期管理等研究尚不多见。制造系统本身也有生命周期,即便是可持续制造,也不可能实现在无限时间上的可持续性。界定可持续制造研究的时间尺度,对制造系统展开生命周期管理研究也是一个可以尝试的领域。
3. 2 可持续供应链管理
一个企业是无法单独承担环境责任的,供应商、运输商、使用者的绩效都能对环境产生不利影响[25],所以制造商要驱使供应链上的其它组织共同遵守可持续性标准。
Gunasekaran & Spalanzani指出,供应链管理包括管理上游供应链和下游配送链。上游供应链管理包括自制或购进的决策、业务外包决策、虚拟企业运作、选择供应商、内包或离境外包等。下游配送链运作包括运输、仓储业务、集中托运、码头和庭院管理、包装及开包、库存控制、管理第三方物流、物流信息系统等。可持续物流运作应包括减少空间、能源、人力、库存的占用和使用,以及更容易的物流追踪、更好的存货周转、最小化的运输成本、减少包装材料的使用等[12]。
逆向供应链又称逆向物流,是为再制造、回收、处理和有效使用资源而使产品从消费环节回流到生产环节的过程。Rachuri et al. 认为逆向供应链与正向供应链同等重要,因为它既影响回收的经济和环境价值,又影响末期产品的返回[26]。逆向物流问题可以经由独立的和整合的两个途径解决,独立的方法假设正向供应链独立于逆向供应链工作,整合的方法则将二者同时考虑,并考虑他们的相互作用[13]。如果能够有效整合、协同正向和逆向两个方面的运输安排,在中央仓库和回收中心寻找经济的运输数量[27],则可从整体上进一步减少物流成本和时间,提高供应能力。
综上,可持续的供应链是一个由原料供应链、产品配送链、废品回流链组成的闭环结构。可通过选择业务伙伴,追踪物流,整合正向和逆向运输安排,构建运输成本模型、位置库存模型等手段,解决供应链生态和经济维度的可持续性问题。制造系统内各单元的经济效益、生态效益和社会效益,从长期和整体来看是不可分割的。未来生产者将更多地扮演运作者、回收者、服务者、协作者的多重角色。
3. 3 商业模式转型
在传统的商业模式下,制造商要卖出尽可能多的产品,会设法缩短产品生命周期或鼓励顾客转用最新的产品,这必然导致资源的浪费,从长远看是不可持续的。因此,可持续制造的实现需要制造业商业模式的转型。Westkmper指出,制造业的商业模式应从注重“成本、廉价劳动力、质量、泰勒主义”,转化为注重“高附加值、竞争力、可持续性、创新”[28]。Erastos Filos也持类似看法,认为可持续制造需要实现从“以最小资本获得最大收益”到“以最少资源创造最大增加值”模式的转变[21]。
Frank van der Zwan & Tracy Bhamra主张制造业走服务密集之路,即以非物质的服务代替产品,从而减少环境影响,实现生态效率。他们把这种服务称为“生态效率服务”,并把生态效率服务分为产品服务、使用服务和结果服务3种类型。每种服务有不同的形式和特点,但都能带来产品需求数量减少、材料和资源使用减少的结果[29]。Yoshikawa提出的“最小化制造,最大化服务”范式[30],同样试图通过服务对产品的替代在减少环境影响的同时增加制造业的总价值。
基于“产品———服务系统”的商业模式关注产品的使用绩效,而“可持续的规模定制”则关注回应每位顾客的需求。后者是一种整合了可持续性三大支柱和规模定制策略的商业模式,不仅可以满足顾客不断增长的对绿色产品的需要,而且会提高企业与社会责任相关的地位[8]。按订单制造可以大量减少在旧的大规模生产范式下卖不出去的产品,而且在设计阶段就整合可持续发展理念,更接近完全的可持续制造[2]。
Butala & Oosthuizen提出一个用于不发达地区的可持续制造网络模型。认为网络化的制造系统为合作设计、合作开发、合作生产提供了新可能,提供了竞争力、创新、敏捷、重构和改造的基础。它使相互联接的伙伴形成长期的商业联盟,相互交流、合作、协同、竞争,分享信息、知识、资源、风险,共同应对商业机遇,取得整体效应[31]。事实上网络化制造不仅适用于不发达地区,发达地区对这一模型的使用更加普遍且更具成效。
从成本控制转向价值增加,是企业内部战略的转型; 从竞争转向合作,是企业间战略的转型; 从以产品为中心转向以服务为中心,是企业———客户间战略的转型。经济可持续性不仅仅是要维持当前的运作水平,也要持续地渗透到新的市场,通过取得增加和发展替代失去的东西。互联网已经给人类社会,包括制造业带来了重大影响。不久的将来,互联网技术和互联网思维将加速制造业商业模式的转型,并将在开放共享、竞争合作、协同共生的基础上,创造出多元的、全新的商业模式。
4 可持续制造的外部路径
Masaru Nakano把制造业的风险分为内部的、供应链的、制造产业的、全球社会的4种,并依此提出了“可持续社会———可持续制造———可持续供应链———可持续企业”的思路[32]。显然,除了制造系统内部要采取措施主动变革外,可持续制造的实现也离不开外部力量的激励和约束。可持续制造的外部路径主要是从宏观的视角,关注打造适宜的外部消费环境、政策环境、教育环境等。
4. 1 可持续消费拉动
最初的可持续制造实现路径只强调生产系统的改变,但人们很快发现,持续增长的消费抵消了生产领域取得的进步。1992年里约峰会成为国际社会思维方式从只关注生产体系转为生产、消费都关注的分水岭。包括欧洲2010年进行的一项针对5700名来自中国、法国、美国等7个国家的调查对象[8]在内的许多实证研究都证实: 消费者的环境意识在逐步提高,绿色产品的市场也将不断扩大。
心理学、社会学、营销学的研究揭示,消费者行为不只是对价格信号的理性反映,还受社会的、心理的、技术的、环境的诸多因素的影响。Jansson et al. 从个人层面考察了影响消费者可持续消费行为的主要因素。他以Stern的VBN理论为框架,研究了价值观、信仰、个人准则、习惯、以前的采纳行为等因素对汽车消费者的两种绿色消费行为———“绿色削减”和“对生态创新产品的采纳”的影响。发现上述因素都对消费者的绿色消费意愿有明显影响,但对消费者绿色消费行为的影响则依行为类型不同而有所差别[33]。Hans - Ulrich Zabel则将视角扩展到社会因素对个人消费行为的影响,提出: 激发个人的利他、合作、关怀等内在潜力,使个人在决策和行动时变得更自主,是从个人层面建立新的构建推进可持续行为的一个方面; 与此同时,还应重视制度对个人行为的塑造作用,通过文化和情景影响个人行为,在制度和个人间构建可持续导向的互动网络[34]。消费模式的改变,是一个从认知到态度,最后体现在行为中的渐进过程。消费行为既是一种经济行为,又是一种社会文化行为,在引导消费模式朝可持续方向转型的过程中,既要把消费者当做经济人,考虑理性因素对其消费决策的决定作用,又要把消费者当成社会人,发挥社会文化因素对其消费决策的巨大影响。只有相关的社会和个人因素都发挥作用时,可持续消费才能更快地成为主流行为模式。
实现可持续消费将挑战社会的福利状况和人们的生活方式,对不同国家也有着不同的现实要求。Pogutz & Micale提出,改变消费水平和模式有两种策略:( 1) 转向低环境影响的消费品;( 2) 降低物质需求。降低物质需求并不是降低消费,而是转向不同的、更少物质或更少环境密度的生活方式[35]。Petry et al. 也认为可持续消费并不意味着减少消费,达到全球可持续消费需要减少发达国家的消费,增加发展中国家的消费[36]。
4. 2 政策及标准规制
市场是被人类制度限定的,政策可以提供一般性刺激因素和注意力导向因子来引导相关利益主体的行为。Westkaèmper et al. 将环境保护措施和法规的演变归纳为4个阶段: 20世纪60 ~ 70年代开始认识到单个风险,呼吁规制; 70 ~ 80年代主要进行物质规制,采取末端治理的污染防治办法; 80 ~ 90年代,开始进行整合的环境保护,关注可持续性; 90年代后,趋于解除规制,更多采取生态税等市场驱动的机制[22]。
可持续制造相关政策是一个包括环境政策、创新政策、产业政策,涉及供给和需求两个方面,卷入政府、企业、消费者等各主体的复杂政策网络体系。以OECD为代表的国际机构在可持续制造的政策研究上已取得了较多成果。OECD开展的可持续生产领域的环境政策研究包括企业行为和环境政策、政府刺激环境管理系统的角色、中小型企 业的不同 体制需求 等。2011年OECD推出了绿色增长的政策框架,包括政策设计、市场工具、法规和监管、改变消费者行为、创新、基础设施投资、制度和治理7个部分。其中政策工具包括: 总量管制与排放许可证交易体系、基线和信贷许可证系统、对污染或资源使用征税、押金退款 制度、绩效标 准、技术标准等[37]。联合国环境保护署 ( UNEP) 划分了3种政策工具: 监管工具、基于市场的工具、基于信息的工具。监管工具要求特定的行为; 基于市场的工具激励特定的行为,将公司的污染行为与税收、罚款、收费联系在一起; 基于信息的工具通过提供某种信息改变行为[38]。由于政治、经济、文化背景的差异,以及制度变迁的路径依赖,对国外政策研究成果简单地采取拿来主义,必然水土不服。结合本土特定环境,开展构建有中国特色的可持续制造政策支撑体系的研究,尤其是制度创新研究,是一个值得重视的研究方向。
政府的法规常需以产业标准为支撑。标准的出台能显著减少交易成本和研发风险。标准还有催化特性,能推动新技术的快速扩散和技术转化。近20年来,各国、各组织陆续制定了多种推动可持续发展的标准,主要包括: 国际标准组织的ISO14000系列标准; 废电子与机电设备指令WEEE; 有害物质限制指令Ro HS; 化学品的注册、评估、授权和限制规则REACH; 交通工具生命末期指令ELV; 印制电路协会的IPC - 1752以及联合产业指南JIG - 101等。由于众多的标准彼此间没有组织和联系,导致企业很难弄清哪些是与己相关的、哪些对自己是最重要的,也很难处理不同标准间的重叠及协调问题。
4. 3 教育及学习支撑
对未来的工程师和设计师进行可持续发展观念和可持续能力的培训是实现可持续制造的重要前提。教育也是消费者和普通人通过合适的生活方式和正确地使用产品和技术,达成可持续性目标的先决条件。当前的可持续性教育研究大多是针对生产者教育的,且主要着眼于教学内容的设置和教育方式的创新。
Petry et al. 总结出多元学习、多元途径、双闭环学习、灵活的转化学习等4种学习途径,还研究了短期培训、针对具体部门生产和消费的教育、导向可持续发展创新的社会学习等5种对可持续消费和生产进行教育干预的策略及案例[36]。Rochon et al. 研究了美国大学可持续生产教育的历程和现状以及普渡大学可持续教育的跨学科方法及其国内和国际合作网络[39]。Cerinsek & Dolinsek指出,为了满足制造的可持续性要求,不仅需要改变大学工科的课程设置,创造新的学习模块; 而且需要开发和使用新的学习方法和环境。他们提出一个能力框架,列出7种工程师应对各种可持续制造问题必须具备的能力,该框架可帮助教育机构调整课程设置和教育方案[40]。欧洲的TARGET项目开发出一种新的学习环境,支持在创新、项目管理、可持续制造等学习领域的快速能力开发。TARGET平台的核心构件是一种与虚拟世界技术相连的严肃游戏。开发这种严肃游戏的一个重要挑战是要在游戏设计时量体裁衣,系统要能评价玩家的专业水平,并依此提供合适的游戏情节[41]。
可持续消费作为需求力量可拉动供给方朝可持续制造范式转型; 政策法规作为规制力量可推动政策对象建立可持续的生产系统; 对生产者和消费者的可持续性教育作为基础力量可支撑可持续的生产和消费。三者和其它外部条件一起,共同形成导向可持续制造的外部氛围。
5 可持续制造评价
Bi指出可持续制造系统的3个最重要的成分是: ( 1) 选择和应用合适的指标测量制造的可持续性; ( 2) 实现综合的、透明的、可重复的生命周期评价; ( 3) 基于选定的指标和生命周期评价优化系统[1]。由此可见可持续性评价的重要性。可持续制造评价指标体系的建立为企业指明了努力的方向,可持续性评价结果可以帮助企业找出需改进的关键环节。
5. 1 评价指标体系
基于现在已有众多评价不同层面可持续性的指标体系,且这些指标广泛而分散,一些学者对已有指标体系的评价侧重点和使用情况进行了调查。Feng et al. 研究了道 琼斯可持 续性指数、OECD的核心环境指标等8个可持续性指标体系[5],Labuschagne et al. 分析了全球报告倡议( GRI) 、联合国可持续发展委员会指标等4个指标体系[42],都发现: 大多数指标体系关注国家、地区、社区或公司整体的可持续性,对操作层面的可持续性测度不足; 现有指标体系主要测量的是可持续性的环境维度,社会维度的指标没有得到应有的重视。德州理工大学先进制造实验室在全球报告倡议 ( GRI) 的基础上,选择了涵盖环境、经济、社会3个维度,涉及能源和材料使用、对自然环境的排放、经济绩效、产品、工人、社区发展和社会公正6个方面的32个指标,对其使用情况进行调查。发现其中20个指标是公司用过且认为重要的,所有的产品指标都包括其中,显示出产品绩效和质量仍然是大多数公司最关注的; 8个指标没用过但被认为很重要,这些是需要通过政策标准和其它刺激计划推动的指标; 4个指标既没用过也不被认为重要,这当中有3个是社区发展和社会公正指标,意味着制造业的社会影响还处于被忽视的境地[43]。
另一些研究则致力于设计综合全面的指标体系。如美国国家标准与技术研究院在分析环境可持续性指标、环境绩效指数、欧盟环境机构核心指标体系等11个指标体系的基础上,对可在工厂操作场所评价制造流程和产品可持续性的指标进行界定、选择、整合、归类,形成一个结构图和指标库。该指标库总共有212个指标,分别属于环境整治、经济增长、社会福利、技术进步、绩效管理5个维度。企业可以从中选择评价自己产品和工艺可持续性的指标[44]。Bi把制造分为“制造前、制造、使用、使用后”4个阶段,从“环境、社会、经济”3个维度来考察指标[1],如图1。
指标体系的建立是对可持续制造这一总目标的具体化。由于在“何为可持续制造?”这一基础问题上众说纷纭,指标体系的构建自然呈现出百花齐放的局面。广泛而分散的众多指标体系会导致选择时的困惑,由于没有使用统一的度量单位,也难以在指标体系间进行比较和分析。动辄包含上百个指标的综合指标体系又会导致使用时的复杂,企业根据自身情况从中选择合适的指标一则考验企业的选择能力,二则选择过程必然包含企业自身的价值判断和价值偏好,最后测量的结果也很难在企业间进行比较。建立科学、合理、操作性强、适用面广的指标体系仍然是一个难题。
5. 2 评价工具
常用的可持续性评价工具主要有生命周期评价、层级分析法、离散事件模拟等。
生命周期评价 ( LCA) 目前被广泛用于评价产品或流程的环境影响,ISO14040 - 14043分别提供了生命周期评价的原则和框架、目标范围的界定以及清单分析、影响分析、生命周期阐释的国际标准。全面的LCA是耗时且需要大量具体数据的,因此需要一些简化的LCA方法以可接受的精确度进行产品环境影响的早期估算。Kaebernick et al. 提出的群体技术方法,在识别出群的“影响驱动者”并得出环境绩效指标方程式的基础上,只需要基本数据就可以评价产品的环境影响[23]。Rebitzer et al. 提出了3种简化的生命周期分析法: 一种是对流程模型进行直接简化,减少生命周期清单分析的工作量; 第二种是基于输入———输出分析的生命周期评价,用经济流动数据模型化由供应链构成的产品系统; 第三种是混合法,把前两种方法结合在一起,克服两者的不足[45]。针对使用LCA存在数据缺乏、数据难加总和难分解的问题,Sudarsan Rachuri等建议: 建立全球数据储存库,开发可追溯的生命周期库存数据; 创造软件基础设施,收集、分析、转换、加总可持续信息; 构建开放通用的、可扩展的、易分享的源模型[3]。
层级分析法 ( AHP) 的优势是通过层级分解可以简化复杂的决策问题,同时清晰地强调了在不同目标和利益间的权衡,但它也存在诸如不考虑元素间的 相互依赖 性等不足。分 析网络法( ANP) 可以克服这种不足,该法将所有相关的属性和替代方案都联系在一个相互依赖的网络系统中,提供了对决策属性的非线性分析策略。为了避免与认知投射相关的不确定性,还可以使用模糊网络分析法消除数据的含糊和不准确[46]。
使用整合的评价模型可以从多个层面更详细地对制造系统的可持续性进行评价。SIMTER是一个基于计算机系统的、整合的生产系统模拟和环境分析工具,它共分3层: 高层是离散模拟工具,分析生产流程、效率和其它重要的绩效问题; 中层是工作站层面,关注任务、工作场所、加工步骤; 低层是产品层,需要材料数据和部件维度进行分析。使用SIMTER能更详细的进行生命周期评价,通过对影响每个产品的路径进行动态的离散事件模拟,还可以进行历时的因果测量[47]。Pineda - Henson & Culaba提出一种整合了生命周期评价和层次分析法的制造流程绿色生产评价诊断模型,并在半导体装配和包装操作中进行了应用[10]。Paju et al. 的可持续制造图法将生命周期评价、离散事件模拟和价值流图3种方法的要素结合在一个易于使用、高可视化的模型中,用于生产控制监测并改善所界定的指标[48]。
其它测评工具还有: 数据包络分析法、环境成本核算法、绿色会计等。每种工具都有其优点和适用范围,需根据实际情况和测评需要选择或整合使用。
虽然国外学者在可持续制造的概念界定、实现路径、测度评价等方面已经开展了广泛的研究,取得了大量有价值的成果,但还存在一些不足之处有待深入探索。
( 1) 可持续制造的基础理论研究薄弱。在一些核心问题,如什么是可持续制造? 可持续制造的特征是什么? 判断可持续制造的标准有哪些?等方面要么存在较大争议,要么描述笼统含糊。而在如何对这个核心概念进行操作化定义? 可持续制造研究的时空尺度如何划定? 等问题上更是基本未有触及。这就使得可持续制造研究要么局限于技术本位,要么漫无边际。从核心概念的界定方面进行突破,并依此划定研究的边界,是进一步研究的关键。
( 2) 可持续制造研究是一门交叉学科,尽管学者们从不同的学科角度对可持续制造的实现路径提出了许多新思路、新方法、新模式,但这些理论成果中哪些得到了实际应用? 应用效果如何? 等均有待实证检验。在实证研究的基础上对相关理论成果进行检验、修正和细化是未来研究的一个着眼点。
( 3) 现有的可持续性评价指标体系大多是建立在全球生态系统承载能力的绝对标准之上的。不同地方的资源环境条件、经济发展水平、文化政治背景不一样,当求解制造业的可持续发展函数的时候,当地制造业发展所依赖的背景特征,尤其是生态脆弱性和弹性,是必须考虑的重要约束条件。界定可持续制造研究的空间尺度,依据空间特定性建立起测度制造系统可持续性的相对标准,并在此基础上创建模型对制造系统对地方生态系统、地方经济发展和人的福祉的影响进行动态模拟似乎更具实践指导意义。
可制造性 第6篇
早在3500年前, 茜素就在中亚、埃及、欧洲和中国被作为红色染料使用。第一次煮玫瑰茜草的根会出现鲜艳的橙色、红色和粉红色, 1826年, 法国的皮埃尔让确认了茜草根含有两种染料, 即茜素红及红紫素 (羟基茜素) 。这种曾在过去被作为天然植物染料用于制作热焰红的纺织品, 现今通过最新技术, 可用来制备新型“绿色”电池。
莱斯大学机械工程及材料科学系教授雷迪博士指出, 大多数锂离子电池电极依赖于开采有限的金属矿石, 如钴。
可制造微型机器人的纳米“铁磁纸” 第7篇
这种特殊材料是采用矿物油和氧化铁“磁纳米微粒”浸透在普通纸张或者报纸上形成的, 然后这种带有纳米微粒的纸张可在磁场中应用。该新材料以低成本方式制造小型立体扬声器、微型机器人或者具有多种用途的发动机, 其中包括控制细胞的镊子和最低程度侵入手术的柔韧性机械手指。
一旦普通纸张上浸入“铁磁流体”混合物, 纸张就覆盖着一层生物塑料薄膜, 它具有一定程度的抗水性, 避免液体蒸发, 并能显著提高强度、硬度和弹性等机械性能。由于这项技术成本并不昂贵, 不需要特殊的实验室制造, 它可普遍地应用于大学和高校制造微型机器人和其他工程科学器件。这种纳米等级磁性微粒可从商业途径获得, 磁性微粒的直径仅有10纳米, 相当于人体头发的万分之一。铁磁纳米微粒中含有铁原子。
可制造性 第8篇
激烈的全球化市场竞争、客户需求的个性化以及产品更新换代的加快, 要求制造系统具有快速、有效和低成本地适应各种变化的能力。显然现有的制造系统无法满足这一要求, 需要发展一种能够通过对制造资源的动态重组配置和信息的高度集成来满足变化莫测的市场需求的制造系统, 可重组制造系统就是在这样的背景下产生的。针对市场需要的快速变化, 可重组制造系统最大限度地利用原有制造资源对系统进行重组、替代、整合及升级, 使其能最快地适应新产品的生产。
目前, 工艺规划都是一种串行处理过程, 产生的工艺对产品对象、制造环境和生产类型有很强的依赖性, 并且工艺的可重用性差, 而可重组制造系统面对的是快速变化的产品和制造设备, 甚至是快速更新的生产工艺[1,2]。在可重组制造系统中, 由于车间生产过程处于复杂多变的环境, 同时存在各种不确定的扰动和变数, 需要经常对生产工艺进行重组。因此, 如何准确地描述工艺过程是制造系统进行快速重组的重要前提。
1 工艺过程描述研究现状
准确描述工艺过程是生产能力平衡以及进行生产调度的前提条件, 但至今尚未有公认的、完美的工艺过程描述模型, 目前主要有以下几种工艺过程的描述方法:
(1) ISO工艺计划概念。ISO工艺计划模型[3]的目标是描述执行工艺过程每个步骤所需的信息。它试图提供一个通用的模型组件集合, 使得任何工艺过程, 如制造、装配、检验、维护、测试、修理等, 都能利用这一组件集合。
(2) 工艺描述语言。工艺描述语言 (a language for process specification, ALPS) [4]是美国国家标准技术研究院开发的适于离散制造的一种语言。与ISO工艺计划模型不同, ALPS不是国际化标准, 而是一种实验语言。它是建立在有向图结构的基础上, 有向图中每一个节点都具有自身的属性和系统定义的属性。ALPS定义了终端节点、任务节点、分离节点、合并节点、综合节点、资源节点和信息节点等7种类型的图形节点。
(3) 过程描述语言。美国国家标准技术研究院的PSL (process specification language) [5]标准认为, 任何事物都可归类于活动、活动事件、对象和时间点中的一类。工艺计划是任务序列的集合, 其基本元素是任务、任务执行者、制造资源和时序关系。
上述模型虽然能够对工艺过程进行描述, 但都忽略了各道生产工序具体状态的描述, 不能准确地描述完成了哪些工序, 还有哪些工序没有完成, 以及各道工序的加工进度。在可重组制造系统中, 企业制造资源都是动态变化的, 工艺技术和工装设备的改良、加工批量的变化, 都可能对工艺过程产生影响, 因此本文提出了一种适于动态制造环境的工艺过程描述方法。
2 工艺可重用的层次性模型
工艺文件有很大的相似性和重用性, 即便是完全不同的零件, 其工艺文件的某些步骤也是十分相似的。而且对于越小的工艺描述单元, 其相似性越高。有了共性就可以从中抽取出常用的, 较为固定的工艺描述。
机械加工零件, 无论其几何结构多么复杂, 都可以看作是由各种表面元素构成的。从加工制造的角度来看, 这些表面元素可以抽象为一系列的特征fi (i=1, 2, , n) 。特征可看作是直接与加工制造方法相联系的抽象几何表面。因此, 把以特征为核心的有关特征加工工序的相关信息所形成的实体, 定义为工艺元, 并用三元组表示为
peij= (fi, MPij, MRij) j=1, 2, , m (1)
式中, MPij为对特征fi进行加工所采用的加工工艺;MRij为采用加工工艺MPij加工特征fi所需的制造资源。
一个特征的全部工艺元构成该特征的加工元, 并表示为
pei={pei1, pei2, , peim} (2)
工艺元是零件工艺设计的基本单元, 是组成工艺过程的最基本模块。由工艺元可组成工艺模板, 工艺模板是一组工艺元的有序集, 其往往是针对一类典型零件的参数化工艺。典型工艺一般是针对典型零 (部) 件编写的一组完整工艺文件, 提供的是对过去编制的完整工艺文件的一种重用途径[6]。可重组制造环境下, 工艺信息具有层次性的特点, 各个层次的工艺信息都是变型的原始信息, 也即是可重用的信息, 如图1所示。工艺可重用的这种层次性思想增强了工艺信息重用的灵活性和适应性。
3 可重组制造环境下的工艺过程描述
3.1工艺加工顺序的表达
工艺是多个工序组成的, 工序是由多个工步组成的, 这些工序和工步包括工艺描述、工时、工装和工艺附图等, 其中工艺描述文本是工艺知识的主要表现形式。设一条工序表示为Ti={peij|i=1, 2, , m;j=1, 2, , n}, 即一条工序描述包含多个工艺元。则工艺的加工顺序可表示为
T={T1, T2, , Tm|f (T1) <f (T2) <<f (Tm) } (3)
式中, m为有效的加工工序总数;f () 为加工顺序函数。
这样, 整个工艺就可以看作是以函数f () 为序的工艺描述序列的集合[7]。
在可重组制造系统中, 对于零件的加工工艺路线, 除了某些工序之间存在着严格的工序顺序之外, 多数零件的部分加工工序之间在逻辑上并没有明显的前后顺序关系, 这些工序称为并列工序[8]。并列工序增加了制造系统工艺的柔性, 提高了企业制造资源的利用率。设某零件共有m道工序Ti (i=1, 2, , m) , 其中第k道工序到第l道工序为并列工序1klm, 当工序Tk-1加工完成后, 工序Tv (kvl) 中的任何一道工序都可以开始加工, 当Tv代表的所有工序都加工完成后才可以进行Tl+1的加工。由此, 该零件工艺的加工顺序可表示为T={T1, , Tk, , Tv, , Tl, , Tm|f (T1) <<f (Tk) =f (Tv) =f (Tl) <<f (Tm) }。
利用非循环单向图对工艺过程进行描述, 非循环单向图具有开始节点、结束节点和任务节点三类节点, 箭头描述了任务节点执行的先后顺序[9]。图2所示为利用非循环单向图对某工艺过程进行的描述。其中, “or”关系表示可选的工序, 这些工序只选择其一即可, 用“and”关系表示一条工艺路线中的并列工序, 这些工序前后顺序可调, 也可同时加工, 但都必须加工。
3.2工艺过程的状态分析
零件的加工过程可以看作是从毛坯到成品不断变化的过程。在某道工序的加工过程中, 零件处于一个确定的加工状态, 这个状态是多个特征的组合状态, 即构成零件特征的组合状态, 称之为特征组态。加工过程是一个零件特征组态不断改变的过程, 一个零件在各个工序的状态是互不相同的, 将特征在每道工序加工时所处的状态用一个编码来标定, 称之为状态码[10]。由于在加工过程中, 每个特征都处于一种加工状态, 都有一个相应的状态码, 因此每道工序的状态由多个状态来标定, 将这些状态放在一个元组里, 就可以用一个元组来标定工序的状态, 称这个元组为状态元组。
在工艺过程中, 零件的各个特征都不是独立的, 应该看成一个整体, 它体现了零件各个构成部分的加工过程, 使用以下元组来表示一个特征:
fi= (STi, UTi, Oi) (4)
其中, STi为一加工状态元组, STi= (Si1, Si2, , Sim) , 取值如下:
为一加工位置元组, UTi取值如下:
Oi是一个整数, 称为次序数, 表示特征fi最终被加工完成的工序号。特征通过次序数与工序建立一一映射关系, fi将在第Oi道工序完成加工, 形成它的最终状态。
工艺过程中零件的工艺状态由各个特征在每道工序的状态决定的, 将所有的状态元组放在一个向量中构成一个状态矩阵SA, 表示如下:
SA=[STT1STT2 STTn] (5)
式中, STj是状态元组STj的转置, 这里状态元组STj被看作是一个行向量。
将所有的位置元组放在一个向量中构成一个位置矩阵UA, 如下所示:
UA=[UTT1UTT2 UTTn] (6)
式中, UTj为位置元组UTj的转置, 这里位置元组UTj被看作是一个行向量。
图3是针对图2所示的工艺过程给出的某零件各个特征及工序的状态举例, 该零件共有6个特征构成, 各个特征的加工元表示为pei。工艺过程包括9道工序, 其中工序3、工序4和工序5为并列工序, 工序7和工序8为可选工序。
特征与工艺过程的映射是通过次序数来实现的, 将所有的次序数放在一个向量中, 构成一个长度为n的次序向量OA= (O1, O2, , On) 。由次序向量OA确定的特征放在一起构成一个向量:
ZA= (ZO1, ZO2, , ZOn) (7)
称为特征的控制向量, 记ZA为Z (OA) 或Z (O1, O2, , On) 。
定义1 取状态码函数。设某个特征的加工位置为uij, 该特征对应的最终状态为ZOi, 用S (ZOi, uij) 表示特征在uij上加工状态对应的状态码, 称之为取状态码函数。
定义2 取状态码算子∇。设特征的加工位置元组为UT, 则特征在工艺过程中的加工状态定义为
称∇为取状态码算子。
设加工元的位置矩阵为UA= (UTT1, UTT2, , UTTn) , 该位置矩阵相对应的控制向量为ZA= (ZO1, ZO2, , ZOn) , 定义
对于某个特征fi, 其状态元组、次序数和加工位置元组满足以下关系:
STi=ZOi∇UTTi (10)
工艺过程的状态矩阵、控制向量和位置矩阵满足以下关系:
SA=ZA∇UA (11)
通过式 (11) 可以得到每道工序在加工过程中的中间状态的描述。
在可重组制造环境下, 制造资源都是动态变化的, 为了使工艺规划更好地为生产调度服务, 需将两者加以动态集成[11]。生产调度通过工艺过程状态信息, 及时处理设备故障、生产任务突变等车间突发事件, 并做出相应的工艺方案调整或工艺再设计。
对工艺过程进行调整时, 可以根据控制向量和需要调整的工序号来确定重排的工艺特征。设需要调整的工序号为t, 确定该工序上加工的特征即为重排特征, 全部重排特征构成的重排特征集合Ft={f1, f2, , fn}, 由此可得重排特征的控制向量, 即Zt= (O1, O2, , On) 。重排特征中从工序号t到次序数Oi之间的工艺元为重排工艺元, 相应的重排工艺元集合Pt={pe1t, pe2t, , penm}。把各个重排工艺元作为重用的原始信息, 对其进行重新调整, 各个工艺元可以采用不同的加工方法或同一加工方法中选取不同的机床来实现。根据生产调度反馈的制造资源实时信息, 对每一种加工方法对应的设备进行优先级排序, 首先选用优先指标高的设备。
4 实例分析
下面以某企业柴油发动机缸盖为例分析动态制造环境下的工艺过程描述方法, 缸盖零件如图4所示, 其主要由上平面 (f1) 、下平面 (f2) 、进气面 (f3) 、排气面 (f4) 、前端面 (f5) 、后端面 (f6) 、进气座圈孔 (f7) 、排气座圈孔 (f8) 、导管孔 (f9) 、进气面螺纹 (f10) 、排气面螺纹 (f11) 、水孔 (f12) 、喷油器孔 (f13) 和挺杆孔 (f14) 等14个特征构成。
缸盖的加工工艺采用先面后孔和先粗后精的原则生成, 其中各孔的加工工序为并列工序, 在完成平面加工的情况下, 可以根据机床负荷状态等实际生产情况动态确定如何安排各孔的加工顺序。利用非循环单向图对具体工艺过程进行的描述如图5所示。
根据缸盖工艺过程可得到零件各工序与特征之间的关系, 由此确定各个特征的位置矩阵UA, 以及各个特征的次序数, 根据式 (7) 得到控制向量
ZA= (4, 4, 2, 2, 3, 3, 9, 9, 9, 14, 14, 6, 13, 12)
生产过程中, 工序5在完成27%的任务后设备出现故障, 根据各个特征的加工状况, 通过取状态码函数由式 (11) 可计算出状态矩阵SA:
由此可得工艺过程状态
S= (1, 1, 1, 1, 0.27, 0.85, 0.93, 0.87, 0, 0.35, 0.6, 0, 0.2, 0.4)
由于工序5的设备出现故障, 需要对工艺进行调整。通过控制向量ZA确定重排特征集合F5={f7, f8, f9}, 重排工艺元集合P5={pe57, pe58, pe59, pe97, pe98, pe99}, 对以上工艺元进行调整。根据企业生产调度反馈的制造资源实时信息, 目前有一台加工中心可以使用, 对工序5和工序9进行工序合并, 采用该加工中心在一道工序中完成进、排气座圈孔和导管孔的粗精加工。由于工序5、工序9和其他孔的加工为并列工序, 因此该工序的调整不影响其他工序的加工顺序, 确保了工艺过程继续执行下去。
5 结束语
本文针对可重组制造系统中动态变化的制造资源, 提出了一种柔性的工艺过程描述方法。与目前提出的一些方法相比, 这种方法可以清楚地描述零件每道工序的中间加工状态, 以及各个特征的加工信息, 可以处理由于设备故障或工装设备的改良等引起的加工突然中断、工艺信息无法描述的问题。在可重制造系统中, 该方法对于实时了解工艺过程状态信息, 以及根据车间动态出现的情况进行工艺过程的重排具有重要的指导价值。
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[6]戈鹏.敏捷化CAPP系统原理、关键技术与应用实践[D].成都:四川大学, 2003.
[7]高伟, 殷国富, 成尔京.机械制造工艺序列中的知识发现方法研究[J].机械工程学报, 2004, 40 (5) :121-125.
[8]黄学文, 范玉顺.基于二进制和十六进制的物料工艺状态描述方法[J].计算机集成制造系统, 2006, 12 (2) :280-284.
[9]Chang H C, Chen F F.A Dynamic ProgrammingBased Process Planning Selection Strategy Consid-ering Utilization of Machines[J].InternationalJournal of Advanced Manufacturing Technology, 2002, 19:97-105.
[10]曾洪鑫.基于状态树与时间处理的机械产品流水装配生产计划与调度[D].武汉:华中科技大学, 2005.
按摩可促进夫妻“性”福 第9篇
第一阶段,夫妻之间,在安静、无其他干扰的居室中,首先用含蓄、幽默的语言交流思想感情。切忌直接谈及性的问题,只能用暗示语言。然后,互相有意识地靠近肉体,做一些头面部的亲热动作,接着抚摩四肢,使双方感到轻松愉快,消除紧张情绪,进而抚摩胸腹、腰背,但是应避免刺激“性感带”。在紧张情绪得以放松并有亲昵的好感表现时,方可转入第二阶段的按摩。
第二阶段的按摩,针对不同情况可选取如下三种不同方式:
1.接受按摩的一方为仰卧位。从按摩胸、腹部开始,然后触及乳房。如无反应,则逐步过渡到双侧乳房的按摩。然后沿双侧乳线拉长抚摸距离,由乳房经腹部抚摸下腹→腹股沟→大腿内侧→外生殖器与生殖器接触。
2.被按摩者外侧卧位。从抚摸腹部开始,同时以另一只手抚摸背部。因为被按摩的一方处于侧卧位,按摩者可以进行前侧和背侧按摩,逐渐拉大抚摸幅度,前面按摩可由腹部→胸部→双乳房→腹部→下腹→双大腹内侧。以上过程,放在背后的手与放在胸前的手处于同一水平,跟随着抚摸。最后接触外生殖器,并发展成生殖器之间相互接触。
3.被按摩者处于俯卧位。从按摩腰背开始→腰部→胸背→颈部→头部→再按摩回胸腰→双大腿内侧,如此上下往返按摩。按摩至胸背部时,双手可绕至胁下,同时按摸至双侧乳房,再回按摩胸腰。最后酌情接触外生殖器。
事前按摩,要求开始不接触外生殖器,最后可达到性唤起。
先进制造与可持续城市发展（英文） 第10篇
Industry 4.0[1,2,3],the Industrial Internet[4、5],and Made in China 2025[6]are three topics of high economic relevance that touch on the future of our current international value networks.They are intensively discussed in worldwide debates,both in academia and in practical contexts.The three approaches to Advanced Manufacturing aim at a forthcoming“fourth industrial revolution,”which is based on the progressing digitalization process across all industries and services(cf.e.g.,Ref.[7]).
In 2011,the term Industry 4.0 was created in Germany in order to point to a global change in manufacturing and global supply networks.The future deployment of Cyber-Physical Systems(CPS)together with a much closer integration of information and communication technologies(ICT)for manufacturing and logistics may lead to a global fourth industrial revolution.CPS together with cloud services on the Internet enable continuous data collection and data analysis across worldwide value networks based on machine-tomachine(M2M)communication and Internet of Things(Io T)technologies.They also provide the key functions to integrate the shop-floor control systems with business ICT systems.The use of CPS will connect big and especially small and mediumsized companies within global production and logistics networks more efficiently,enabling them to more effectively:
·Apply integrative smart engineering methods across the whole product life cycle;
·Engage in smart mass production,even with a lot size of one;and
·Customize smart products.
The European Commission has also set up a research program in order to implement the concepts of Industry 4.0[8、9],stating:“The mission of the European Technology Platform Manufuture is to propose,develop and implement a strategy based on research and innovation,capable of speeding up the rate of industrial transformation to high-added-value products,processes and services,securing high-skills employment and winning a major share of world manufacturing output in the future knowledge-driven economy.”
Ref.[5]defines the Industrial Internet as“An internet of things,machines,computers and people,enabling intelligent industrial operations using advanced data analytics for transformational business outcomes.”According to Ref.[4],the charter of this industrial association to encourage innovation involves:
·“Utilizing existing and creating new industry use cases and test beds for real-world applications;
·Delivering best practices,reference architectures,case studies,and standards requirements to ease deployment of connected technologies;
·Influencing the global standards development process for Internet and industrial systems;
·Facilitating open forums to share and exchange realworld ideas,practices,lessons,and insights;and
·Building confidence around new and innovative approaches to security.”
Ref.[10]describes the three goals of the Industrial Internet as follows:
·“Intelligent machines:New ways of connecting the world’s myriad of machines,facilities,fleets,and networks with advanced sensors,controls,and software applications.
·Advanced analytics:Harnessing the power of physicsbased analytics,predictive algorithms,automation and deep domain,expertise in material science,electrical engineering,and other key disciplines required to understand how machines and larger systems operate.
·People at work:Connecting people,whether they be at work in industrial facilities,offices,hospitals or on the move,at any time,to support more intelligent design,operations,and maintenance as well as higher quality service and safety.”
The same source then goes on to state(with insertions in square brackets from these authors):
“Connecting and combining these elements offers new opportunities across firms and economies.For example,traditional statistical approaches use historical data techniques[manufacturing execution systems,or MES]where often there is more separation between the data,the analysis,and decision making.As system monitoring has advanced[by the use of CPS]and the cost of information technology has fallen,the ability to work with larger and larger volumes of real-time data has been expanding.High frequency real-time data brings a whole new level of insight on system operations.Machine-based analytics offers yet another dimension to the analytic process.The combination of physics-based approaches,deep sector specific domain expertise,more automation of information flows,and predictive capabilities can join with the existing suite of“big data”tools.The result is that the Industrial Internet encompasses traditional approaches with newer hybrid approaches that can leverage the power of both historic and real-time data with industry specific advanced analytics”[10].
The Made in China 2025 10-year plan[6]was led by the Chinese Ministry of Industry and Telecommunication Technology(MIIT)and is based on input from the Chinese Academy of Engineering(CAE).Made in China 2025constitutes a strategy to comprehensively upgrade Chinese industry,with the purpose of giving China an edge in innovation,green development,and quality goods.This effort is far broader than the approaches of Industry 4.0 and the Industrial Internet,as the efficiency and quality of Chinese producers are highly uneven,and Chinese manufacturing industries need to more effectively cooperate and compete with advanced industrialized economies at higher product quality levels and with smarter products.Thus,manufacturing must be innovation-driven,emphasize quality over quantity,achieve green development,optimize the structure of Chinese industry,and nurture human talent.Therefore,this strategy focuses on the upgrading of the manufacturing sector to improve innovation ability,to integrate informatization and industrialization through green manufacturing,and to foster manufacturing internationalization.It will span the whole manufacturing industry,and identifies ten sectors as priorities:new information technology,high-end numerically controlled machine tools and robotics,aerospace equipment,ocean engineering equipment and ships with high technology,advanced railway traffic equipment,energy-saving and new energy vehicles,power equipment,new materials,biological medicine and high-performance medical devices,and agricultural production machinery.
All these long-term plans and strategies are based on technologies that are available today,namely CPS,the Io T,distributed software services,and Cloud Computing.The application of these technologies to manufacturing is called“Advanced Manufacturing throughout this paper.They are highly dependent on the availability of adequate digital infrastructures and well-functioning logistics systems,and they have a number of repercussions for cities and regions.Accordingly,it is surprising that little work has been done to date on the interrelations between urban development and Advanced Manufacturing,as global manufacturing and logistics will lead to substantial changes during the implementation of the respective manufacturing strategies.Urban-connected,sustainable,and economic activities in the industrial sector will have to be adapted to new local,regional,and global ICT-based value and logistics chains.Therefore,this paper addresses a new field of academic and practical interest in an explorative way,as there is neither sufficient scientific nor practical experience worldwide on the relation between Advanced Manufacturing and urban development.As a first step,this paper attempts to develop an initial hypothesis on the topic rather than providing data-driven or case-based analytical evidence.
In the remainder of this paper,we will begin by providing a brief description of the overarching concepts of Advanced Manufacturing,logistics,and urban development(Section 2).We then discuss Advanced Manufacturing in the contexts of quality of growth,the green urban economy,and sustainable urban development,as defined and interpreted by the German International Development Cooperation(GIZ)[11、12](Section 3).Finally,Section 4 presents some conclusions.
This paper is based partly on the results of a project that was conducted by the German National Academy of Science and Engineering on behalf of the Federal Ministry of International Cooperation[13].
2 The evolutionary path to the Fourth Industrial Revolution,and its impact on urban development
There is a tendency to talk about revolutions,even when major social and economic changes come about over long periods of time and appear to occur in a more evolutionary than revolutionary manner.This is especially true of the“industrial revolutions.”Previous radical industrial changes in production technology may seem to have taken the shape of revolutions,but a closer look reveals that they were in fact much more evolutionary in nature.The same is true of the impact of the different industrial revolutions on urban development.The path to Industry 4.0 will also be evolutionary(Figure 1).
While the first industrial revolution was triggered by large,centralized water-and steam-driven mechanical production equipment that enabled products to be manufactured more quickly and in larger quantities than before,it took almost a century before they came to be ubiquitously employed in production processes at the start of the second industrial revolution.During this period,the new production technologies led to large-scale urbanization of former rural settlements and contributed to urban growth.
Interestingly,the second industrial revolution was triggered by the opportunity to decentralize the electric power supply,enabling the introduction of relatively inexpensive and much smaller drive units for conveyor belts.The assembly line concept broke down many production steps into individual processes so that employees could become more specialized and production costs could be significantly reduced.This had several consequences for urban development in an increasingly industrialized world.On the one hand,production sites became larger and increasingly disruptive and urban growth was accelerated,often leading to extremely poor living conditions for the working classes.This had an impact on the development of new suburbs with better sanitary and health conditions,as well as improved urban hygiene.On the other hand,mass production made automobiles in particular increasingly affordable for the growing middle classes,and thereby contributed to urban sprawl and the clear separation of land uses in the rapidly growing urban areas,such as between industrial and residential areas.
Another century would pass before the start of the third Industrial Revolution,in which the introduction of the first Programmable logic Controllers(PLCs),robots,electronics,and information technologies,occurring in the late 1960s,would make individual production steps much smarter than in the past.In terms of urban and regional development,new hopes were nurtured that ICT could help remote areas to become more competitive and more attractive to businesses and people.It was also hoped that the long commuting distances associated with living in remote locations or in cities on the periphery of metropolitan areas would no longer be a disadvantage,thanks to the new opportunities that teleworking provided for working from home,at least on a part-time basis.Nevertheless,there was a trend toward a return to more compact city structures,and the eco-city concept started to become more and more prominent.The concepts of intelligent cities,ubiquitous cities,and smart cities would be developed later on,enabling better services and facilitating the use of ICT in everyday life.These concepts continue to characterize the current debate.
It would be another 50 years before further innovations enabled another step of improvement in productivity,ushering in the dawn of a fourth Industrial Revolution based on the development of miniature Cyber-Physical Production Systems(CPPS)and specialized Cyber-Physical Systems.These systems are tiny data-processing units with communication capabilities that use sensors as interfaces to the real world,such as positioning sensors(RFIDs,AGPS,etc.),which may enable actor devices.The CPPS are integrated into electronic and mechanical parts.Mechatronics,software technology,and networking are the principal basic components of the Io T and services.Fundamentally,it is the ability to assign identities to extremely small batches of products and materials and to locate them precisely that enables the key Advanced Manufacturing functions of tracking the items involved in production processes at each level of the supply chain,inside and outside of the factory.The Io T thus contains a digital representation of real-world production and logistics,enabling smart planning,optimization,and control of production steps at each section of the supply chain.
However,this automation of complete process networks comes at a price:CPPS systems have an inherent complexity that can no longer be handled by the planning,optimization,and control systems of yesterday—it is simply not feasible to keep tabs on millions of nodes in a network from a centralized point of control.This problem can be overcome through a paradigm shift in which computation processes involving the digital representations of production items which are decentralized and much more autonomy is assigned to these sub-processes than in a centralized architecture[14,15,16,17].
In order to facilitate the necessary information flow,a comprehensive broadband infrastructure is required for the industry,along with new communication standards at the application and shop-floor level so that the subsystems are able to communicate with each other irrespective of their physical location in the real world,thereby implementing the Io T.The industries best suited to the introduction of Advanced Manufacturing are the automotive,mechanical engineering,electrical,chemical,food processing,and ICT industries.
Data and information safety and security and their protection against misuse and unauthorized access are critical to the success of Advanced Manufacturing.After an implementation of Advanced Manufacturing,factories’work organization and the role of employees will change significantly.Participatory work design and lifelong learning will be necessary,as well as training and continuing professional development.Regulatory frameworks will also need to be adapted to Advanced Manufacturing innovations in terms of legal compliance,the protection of corporate data,liability issues,the handling of personal data,and trade restrictions.
The expected benefits of Advanced Manufacturing include increased productivity and efficiency thanks to a reduction in manufacturing uncertainties,as well as resource efficiency thanks to optimization of manufacturing industry’s consumption of raw materials and energy.Advanced Manufacturing,together with Advanced Logistics,can thus make a positive contribution to environmentally friendly industrial production and resource efficiency.Because of its focus on increasing energy efficiency,Advanced Manufacturing may also have a positive impact on climate change mitigation.
The consequences of Advanced Manufacturing for urban development are not yet clear.Advanced Manufacturing will clearly play a role in the continued development of integrated and inclusive smart city concepts,and it has the potential to change urban development patterns.It may also bring industry back to the city,as a cleaner,environmentally friendly production is much less adverse to other land uses such as housing than previous production technologies.This could enable the concepts of the compact city and the city of short distances,both of which support more sustainable urban development.
However,there are also a number of challenges.For example,it is argued that Advanced Manufacturing may have adverse effects on equality and social inclusion in cities,as it may further strengthen the position of better educated and more capable persons while leaving the underprivileged parts of society behind.Moreover,Advanced Manufacturing makes high demands on favorable urban structures and infrastructure conditions as well as functioning planning mechanisms and good governance.Furthermore,one should not underestimate disruptions in residential areas,for example by commuters and the transport of goods,which may be caused by more flexible Advanced Manufacturing-oriented and 24-hour operating production processes.
Nevertheless,the debate about future cities has been slow to incorporate Advanced Manufacturing,even though it is in fact connected with urban development in many ways.Support from intelligent industries is indispensable in future urbanization trends.In advanced countries from 1960~2012,a nation’s intelligent output,intelligent input,and the development of intelligent subject elements had a positive correlation with the nation’s urbanization ratio,and this trend is becoming more evident.Intelligent urbanization will replace labor urbanization[3].
One of the initiatives that link Advanced Manufacturing with urban development is the Morgenstadt(“City of Tomorrow”)Initiative by the Fraunhofer Association,Europe’s largest application-oriented research organization.This initiative describes the link between the city of the future on the one hand and production and logistics on the other as follows:
“In the future,city transportation and handling of goods will happen fluently within intelligent structures of production and distribution—presenting the backbone of sustainable trade,services and urban production.At the same time,essentials have to be provided at any time to all citizens.The city of tomorrow will be involved more deeply in the provision of production and logistic services by providing,planning and monitoring specific urban infrastructure and services for production and logistics.”[18、19]
The Fraunhofer Association has chosen production and logistics as one of its seven research fields in this initiative.The other research fields are energy,buildings,mobility,information and communication,urban processes and organization,and security.Furthermore,“In the city of the future,life and work will be characterized by short distances and by the freedom to realize individual life and work styles.At the same time,people will have multiple opportunities for participating in decisions on the development of their city.Rigid value chains will be replaced by innovative and flexible value patterns.Regarding consumption and economy,the possession of goods will be less important than the sustainable use of goods and systems.Inhabitants of Morgenstadt won’t be exclusively consumers anymore—they become prosumers:producing consumers.”[19].
3 Industry 4.0 and its linkages with quality of growth,the green urban economy,and sustainable development of metropolitan regions
3.1 Background
Quality of growth is a guiding mission of the German Development Cooperation,as far as sustainable economic development is concerned.High-quality economic growth is seen as a prerequisite for productive and decent employment,which is in turn crucial for poverty eradication and for the promotion of equitable economic and social development[11].GIZ has defined the following dimensions of high-quality growth:
·Smart growth1):The promotion of productivity and competitiveness by encouraging the development of a knowledge-and innovation-based economy.
·Sustainable growth:Environmental sustainability in which the economic development of one generation does not constitute a burden to future generations,as well as the transition to a green economy.
·Inclusive/shared growth:The productive participation of all sectors of society in economic processes.
·Resilient growth:The reduction of economic volatility and mitigation of vulnerability to economic crises and their impacts.
·Integrated growth:Improvement of the framework conditions for the cross-border exchange of goods and services.
·Governance for growth:The establishment of strong institutions and transparent,participatory decision-making processes.
These dimensions provide a valuable framework and are used here as a guideline for our analysis.In respect to smart growth,Advanced Manufacturing concepts will clearly contribute to the concept of smart manufacturing ecosystems.It is also possible to examine the linkages between Advanced Manufacturing in an urban context and concepts for the green urban economy and for sustainable development of metropolitan regions.While these two concepts are closely linked with the quality of growth approach,they have a wider scope and transfer quality of growth to an urban context.The boundaries between the three approaches are soft and there are many overlaps.
The Green Urban Economy is a concept that translates the international and national debates about a green economy to the urban context in order to address urban stakeholders.It is based on the assumption that,in a future where the world is predominantly urban,cities should be pioneers of the transition to a green economy.Key elements of a Green Urban Economy as defined by the German Development Cooperation include the following[20]:
·Inclusive economic growth:“Future growth strategies must no longer focus on quantitative goals alone.Rather,there must be qualitative growth that benefits broad sections of the population.In cities in particular,there is a growing gap between rich and poor,and there are growing groups that do not enjoy adequate social and economic participation.”[20]This is where the linkage with quality of growth becomes most evident.Inclusive economic growth refers literally to the inclusive/shared growth dimension.However,the above description demonstrates that it also encompasses other dimensions of the quality of growth approach,such as governance for growth.
·Environmental compatibility:“It is essential that economic growth be decoupled from resource consumption and greenhouse gas emissions.This can be done,for example,by encouraging innovation and environmentally sound technologies.Thanks to their high population density,cities offer opportunities for the establishment of efficient infrastructure networks.”[20]This issue has a particular linkage with the sustainable growth dimension of quality of growth.Linkages with the smart growth dimension are also apparent.
·Poverty reduction:“Inclusive,ecologically sound growth must be geared toward reducing poverty and giving people opportunities in life.This needs to result in more income opportunities,especially in the low-income sector and in the urban informal sector,and improved access to basic municipal services for the poor and in informal settlements.”[20]This element ties in well with the inclusive/shared growth dimension of quality of growth,with special emphasis on the urban poor.
The sustainable development of metropolitan regions as defined by the German Development Cooperation is an approach that responds to the needs of urban agglomerations and metropolitan regions and seeks to improve their governance structures.Four priority multi-sectoral areas have been defined as relevant by the German Development Cooperation[20]:
·Metropolitan regions as innovative business regions:“Metropolitan regions provide a venue for the exchange of goods and information between local,national and global businesses.They attract knowledge-based companies and they promote and implement new ideas that facilitate sustainable economic activity.For this to happen,however,it is essential to create an appropriate framework.”[20]This aspect incorporates most of the features of quality of growth in an urban context.
·Metropolitan regions as inclusive labor markets and residential centers:“By virtue of their economic growth,metropolitan regions provide a wide range of services and jobs from which poor people can also benefit…”[20].This aspect addresses the inclusive/shared growth dimension of the quality of growth approach.
·Metropolitan regions as dense“nexus”networks:“With so many people and so much production and consumption concentrated in one area,metropolitan regions devour tremendous amounts of energy and natural resources.However,given the tightly woven geographical and sectoral links that exist in metropolitan regions,there are good opportunities for improving the efficiency of their material and energy cycles…”[20].This aspect is partly related to the sustainable growth dimension of quality of growth.
·Metropolitan regions as governance systems:“New governance structures are needed for urban agglomerations in order to organize and control the multi-sectoral challenges they face…”[20].There is a close link between this aspect and the governance for growth dimension referred to above.
All three of the approaches described above—quality of growth,green urban economy,and sustainable urban development—share a number of overlaps and linkages.Whereas the quality of growth approach is focused on economic development in general,the concepts of green urban economy and sustainable development of metropolitan regions translate quality of growth into the urban development context.The next section uses the quality of growth approach as a basis for further analysis.Wherever possible and feasible,references are made to the other concepts.
3.2 Smart growth
Advanced Manufacturing contributes to smart growth and promotes the development of metropolitan regions and cities into innovative business regions.Since manufacturing industry around the world is an important part of the global knowledge society,innovations such as CPPS,Io T,and software services drive innovation in Advanced Manufacturing and Advanced Logistics.The requirements for new hardware devices,sensors,and software architectures to handle the complexity of the processes in global production and supply networks will lead to completely new solutions,including Internet services through Internet applications for manufacturing and logistics[21、16].This development will occur mainly in metropolitan regions and larger urban areas[22].
In the context of the 10-year plan Made in China 2025,it is clear that Advanced Manufacturing and Logistics concepts will play an important role in the further development of Chinese manufacturing,since they support the smart growth targeted by the manufacturing plans for both the domestic and export markets.
Advanced logistics is an integral part of Advanced Manufacturing and an essential precondition for participating in international value networks.Apart from the“hard infrastructure”in Chinese cities,there is also a need for efficient logistics structures among logistics companies(a very high percentage of Chinese trucks are driven by their owners),and a global software infrastructure that enables tracking and tracing at any necessary logistic object level.Additional growth will come about as a result of the growing number of Second-Party Logistics Providers who will take over the logistics functions previously handled by manufacturers,as well as Third-Party Logistics Providers offering manufacturers a one-stop solution for all their logistics services[23].
As logistics also plays a very important role in agriculture and the service industry,there will be an additional
benefit to the Chinese economy through the stated emphasis on these sectors in Made in China 2025.
All these factors may result in Chinese cities undergoing local,accelerated efforts to promote Advanced Manufacturing.However,the numerous problems with air and water pollution underline how decisive better urban planning and management,appropriate planning instruments,and transparency and good governance are,in order for Advanced Manufacturing to make a positive contribution to sustainable urban development.
3.3 Sustainable growth
Advanced Manufacturing makes a contribution to sustainable growth.It contributes to the green urban economy by reducing environmental impacts,and it fits well with the notion of metropolitan regions as dense“nexus”networks by providing them with the opportunity to improve their materials and energy efficiency.For example,the regional cross-linking of industrial processes has the potential for considerable resource savings[24、25].In this way,sustainability combines environmental,economic,and social factors into a single concept.Legal instruments demanding sustainability have been created for some years in order to implement national and European sustainability objectives,such as the requirements to incorporate energy management systems and CO2emissions certificate trading.
The data basis available for Advanced Manufacturing and Logistics is far superior to anything that existed previously,thanks to the collection of data by CPS sensors throughout manufacturing and logistics processes.Additional processing of the data on energy and material flows is required in order to generate up-to-date information such as Key Performance Indicators(KPIs).This is where ICT cloud technologies and Big Data analytics can be used to measure and support sustainable growth,since the associated rise in the volume of available sensor data enabling the basis for the implementation of intelligent and flexible control will result in more efficient manufacturing resources in general.
In order to measure industrial sustainability,the Product Environmental Footprint(PEF)is under development in Europe,and it will help develop our understanding of the impacts of products on the environment.The PEF has already been defined for some selected sectors,and it standardizes the environmental impact of a product over its entire life cycle;in which,for example,equivalent CO2emissions during manufacturing,use,recycling,or disposal contribute to the PEF environmental assessment.The PEF for the metal sheets product group will take on an important role in the metalworking industry over the coming years.A total of 38sustainability indicators quantify progress in the key areas of quality of life,intergenerational justice,social cohesion,and international responsibility in measuring sustainability,including the use of renewable energy[16].
In an industrial environment,considerable expertise and willingness are necessary in order to invest in the implementation of energy and resource efficiency measures.Often,these measures are difficult to evaluate,especially in respect to their return on investment and long-term impact.In addition,expertise based on past experience is a crucial and still rare prerequisite for project decisions in that direction.Small and medium-sized organizations,in particular,can only afford such evaluations in situations where very considerable savings are expected.In view of the requirements for sustainability,it is most important to embed resource efficiency within business processes in order to meet the demands of both energy management systems and energy conservation targets,as both organizational and social aspects exert considerable influence.This is clearly demonstrated by the Think Blue initiative launched by Volkswagen AG that has made an internal commitment to deliver a 25%reduction in energy,water consumption,waste,and CO2and solvent emissions per vehicle compared to 2010 levels.
In the future,it will be essential to enable life cycle assessments to be generated automatically,without manual data collection.The conceptual framework for an automatically generated environmental audit is shown in Figure 2,which is parameterized via the central control systems.It can be used to determine cost-saving measures,to review the continuous improvement process,and even to initiate public relations activities.In addition,in the Chinese context,these CPPS provide opportunities to leap directly from Industry 2.0 to Advanced Manufacturing by introducing energy and resource efficiency in manufacturing,especially where the development of new production facilities permits the introduction of new concepts for resource-efficient production(Figure 2).
Sustainability gains may also come from spatial issues[22].Advanced Manufacturing may facilitate mixed urban development and contribute to the realization of the compact city and the city of short distances.Cleaner production and higher environmental standards lead to better compatibility of industrial sites with other land uses.Thus,industrial production can occur in close proximity to residential areas.Moreover,Advanced Manufacturing-based urban production has the potential to operate with smaller lot sizes due to the modularization of production,meaning that fewer storage facilities will be required.This will allow production facilities to be better integrated into existing urban structures or even located as infill developments in urban regeneration areas.
3.4 Inclusive/shared growth
At first glance,the contribution of Advanced Manufacturing to inclusive or shared growth may be less apparent than in the case of the other dimensions of the“quality of growth”approach.It may also not be immediately obvious how Advanced Manufacturing-based production promotes a green urban economy,for example,in terms of inclusive economic growth and poverty reduction,or how it can support metropolitan regions as inclusive labor markets,which is one of the characteristics of urban-regional sustainability.Advanced Manufacturing is often said to be a job-killer rather than a job-creator,due to its inherent automation of production processes.In addition,it is often seen as exclusive rather than inclusive in terms of socioeconomic development.Thus,it may be argued that Advanced Manufacturing will not be able to contribute substantially to making cities more inclusive.For example,the five strategic plans of the Chicago Metropolitan Area since 1999 have all highlighted the regional collaboration and functional assignment of science and technology,industries,and education,and emphasized the rational/functional high-tech divide between the central region and suburbs.These strategic plans aim to upgrade the industrial competitiveness of metropolitan Chicago through the coordinative development of land,employment,and capital[27].
However,these assumptions are not necessarily true in every case.Advanced Manufacturing is oriented toward the modularization of industrial production and the facilitation of a lot size of one.However,this does not mean that production requires fewer employees or that all production processes along the supply and value chains have to be automated.Nevertheless,job profiles will change in general,with increasing numbers of higher-skilled jobs.This shift will require sound education programs and vocational training activities in respective cities and regions in order to increase regional Advanced Manufacturing readiness.Moreover,it should be remembered that Advanced Manufacturingbased production may create new opportunities for small local suppliers and startups to become involved in national and/or international value networks,thus strengthening the economic development of cities and regions.Furthermore,new job creation opportunities in ancillary industries and in the related service sectors should be taken into consideration.
Regarding urban development,it is still very difficult to estimate whether Industry 4.0 will have more positive consequences overall,in achieving more inclusiveness,or whether adverse effects may prevail.Further studies should carefully take into consideration whether and how cities support better education,knowledge creation,and the integration of small enterprises that hitherto have not had many chances to integrate themselves into overarching value chains.
3.5 Integrated growth
There can be no doubt that Advanced Manufacturing contributes to integrated growth.As the global manufacturing industry relies on international value networks,integrated growth is a direct consequence of Advanced Manufacturing and Advanced Logistics at the international level.An important prerequisite is the international transport of materials and goods[16、17、21、23].
An integrated approach must be taken regarding transport as a whole.The vision for transport should be guided by a modal mix that will lead to an efficient,sustainable,economical,safe,reliable,environmentally friendly,and regionally balanced transportation system.Decisions on road expressways,dedicated rail freight corridors,high-speed trains,and movement through inland waterways or coastal shipping must be made holistically,so that the objectives of speed and efficient energy usage are achieved.Policy decisions should be based on the life cycle energy costs of different transport modes.
In order to enable smooth international logistics,it will also be important to foster the transition from Second-Party Logistics Providers to Third-Party Logistics Providers offering a one-stop solution for all manufacturers’logistics services[23].
A well-functioning logistics and transport infrastructure is of the utmost importance for urban development and for the location of production facilities[28、22].If these are not in place,and if reliable transportation of materials and goods cannot be guaranteed,it will not be possible to convince enterprises to locate their facilities in urban core areas.In fact,transportation problems are among the reasons why enterprises are currently still moving out to the periphery of urban areas.In such a situation,the potential benefits of Advanced Manufacturing,such as the generation of mixed urban land uses and the location of production sites in inner-city regeneration areas,are lost.Moreover,commuting distances grow instead of becoming smaller.
3.6 Resilient growth
Resilient growth does not imply the avoidance of all risks at all cost—it is strongly connected to risk management.In the past,resilience in businesses was mostly driven by experience.However,with data-and process-driven Advanced Manufacturing,it is now possible to model the processes involved to a much greater extent(cf.Section 3.3).Therefore,joint risk management procedures backed up by government policies can be designed by cooperating enterprises and deployed in order to integrate resilience into international Advanced Manufacturing networks.Small and Medium Enterprises(SMEs)can plausibly tackle the inherent risks by adopting new Advanced Manufacturing protocols[25、19].Specific Advanced Manufacturing concepts can contribute to risk mitigation as follows:
·The implementation of CPS sensors to record manufacturing data enables resilient production processes to be developed and operated.
·Members of international value networks must share information about technical interfaces in order to enable joint big data analysis.
·There must be jointly agreed-upon manufacturing and logistics checking procedures for resilience at all tier levels of cooperating value networks.
·The order-dependent combination of manufacturing steps can drive the resilient process network design.
·Uncontrolled instabilities in the process chain(e.g.,the“bull-whip effect”)can result in process fluctuations.This can be avoided by recording process fluctuations and by real-time control even before such unwanted events can build up.
·Industrial ICT suppliers must provide migration paths,from classical data recording to cloud technology and big data analysis tools.
·Risk and resilience management must be accepted at both the corporate level and the level of the authorities responsible for infrastructure management,as the frequency and impact of disruptions to industrial processes in production and logistics must be reduced.
In globally distributed supply networks,disruptions occur rather regularly.Robust supply chains that are able to cope with unforeseen events are a vital business capability.In addition to a resilient and flexible supply network infrastructure,businesses need risk-detection capabilities,obtained by performing predictive analytics on a global scale based on big data tools in order to secure customer operations.Risk mitigation must therefore be a part of regular logistics operations rather than an intervention carried out after the event,as is usually the case today.
Regarding their relation with urban development,resilience and risk reduction are very closely related to the capacities of the urban and regional planning system,the available planning tools,and the existing governance regime.Sound planning and implementation can contribute to minimizing risks by promoting better organized and more reliable city patterns and infrastructure systems.The availability of appropriate and effective urban planning tools is decisive for the implementation of planning concepts oriented toward risk reduction,and the governing regime may help to provide transparency and participation.
3.7 Governance for growth
Advanced Manufacturing is closely related to governance for growth.Especially for Advanced Manufacturing and Advanced Logistics in international value networks,governance for growth forms part of all the growth drivers for businesses and governments[21、16、23、17].
In addition to the necessary efforts of businesses to integrate ICT and CPPS functions for Advanced Manufacturing,there must be efforts on the part of governments to determine current deficits and implement timely remedial policies.Governance also plays an important role in creating the right urban framework conditions for Advanced Manufacturing,for example regarding urban planning,development strategies,infrastructure,logistics,and so forth.In this context,metropolitan regions and urban areas should be seen as governance systems.They need to be reformed so that they are able to organize and control the multi-sectoral challenges facing them,especially those linked to Advanced Manufacturing and Logistics.
An analysis of 312 specific actions in 12 smart cities in Europe concludes that to realize more intelligent urban development,governments need to develop a coordinative framework and bridge the interactions among enterprises,organizations,and citizens.In the process toward Advanced Manufacturing,effective control and coordination from governments could play important roles[29].
4 Conclusions
Advanced Manufacturing and Advanced Logistics are topics that have been shown to be relevant to support all the dimensions of qualitative growth.They have high potential to impact the economic development positively,to enable a green urban economy,and to provide an essential contribution to sustainable urban development by its potential positive effects on
·Smart growth,
·Sustainable growth,
·Inclusive and shared growth,
·Integrated growth,and
·Resilient growth,
provided that there is an appropriate governance for growth supporting the concepts of Advanced Manufacturing and Logistics and the supporting economic and urban framework conditions.
These aspects may become decisive for the success of the Made in China strategy and the Chinese urbanization strategy.They are relevant for Chinese-German relations and future cooperation between these two countries.
Meanwhile,Advanced Manufacturing has a profound influence on the ways different urban elements are interrelated and linked,on the ways city residents think and act,and on the ways residents react to nature and society.The vision of a“better city,better life”will only be realizable through a sustainable approach,including Advanced Manufacturing,that fits the essence of human existence and development[30].
Source of Figures
Figure 1:References[13,p17],based on a figure by the German Research Center for Artificial Intelligence and additions on urban development by the Leibniz Institute of Ecological Urban and Regional Development.
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