Craftsmanship and the Guilds in the Late Middle Ages： The Testimony of Des Teufels Netz and of the Mendel Housebooks

Placing the anonymous didactic poem Des Teufels Netz next to the Mendelschen ZwOlfbrfiderstiftung zu Narnberg, we gain most valuable access to the world of craftsmen in the late Middle Ages. Even though the author of the first text pursues mostly ethical and moral concerns, formulating many specific comments about people＇s wrongdoing, his narrative proves to be almost as informative about craftsmen as the Mendel Housebook （short title）. The latter mostly consists of a very large number of illustrations of old craftsmen working in their shops, which sheds important light on the tools available, the work methods, and the impressive differentiation and sophistication amongst the craftsmen. The Housebook was continued until the early nineteenth century, whereas Des Teufels Netz was mostly forgotten and did not experience a significant reception. Both works complement each other well and allow us to gain an excellent insight into the world of craftsmen.

The Digital Age of Mobile Cellular Network in Germany and China:Policies,Technologies and Markets (Part Ⅰ)

The German Postal Reform I in 1989 introduced competition in the mobile cellular market. German cellular operators, DeTeMobil, Mannesmann, E-Plus and VIAG Interkom, built D1-, D2-, E1-and E2-Netze based on GSM standards made in Europe. China Unicom was created in 1994 and China Telecom was separated from MPT in 1995. China Telecom and China Unicom competed in a duopoly from the mid-1990s onwards and the cellular services provided by them also rely on GSM standards. China Telecom additionally deployed XLT technology (PHS) from the late 1990s onwards. While DeTeMobil and Mannesmann conquered approximately 80%-90% of the market throughout the 1990s and were the two dominant market players in Germany, China’s cellular market was mainly controlled by China Mobile. In Germany, prices related to cellular technology continued the downwards trend as a major result of the process of deregulation, liberalisation and competition. In China, price wars had led to significant price reductions in the cellular market. Although network operators in both countries strived to deliver differentiated cellular services, the two national markets in the 1990s were visibly shaped by product homogeneity.

Origin of Mobile Cellular Network Technologies and Markets in Germany and China

The inventive foundation of mobile cellular technologies was laid about 100 years ago. Wireless voice service was commercialised in the 1940s by AT&T. In Germany, public and non-cellular wireless service was established by Deutsche Bundespost in the late 1950s and the first analogue cellular network called C-Netz emerged in the mid-1980s. In China, the first mobile cellular networks called TACS-A and TACS-B were installed by Ministry of Post and Telecommunication in the late 1980s. While describing the events in Germany and China, this paper concentrates on discussing the related technologies and their impacts in the marketplace. A comparison summarises some important findings. Japan and Europe's Nordic countries were the first nations to commercialise the 1st generation analogous cellular technologies. There existed A- and B-Network in Germany and China, but the network nature of them is quite different. The market development in Germany and China was similar. The enlarged network capacity accommodated gradually more subscribers and prices related to the cellular services fell continuously. However, China's fee system was more complicated and has adopted the RPP regime, while Germany has been using the CPP billing. The article concludes that implications such as the relationship between science and technology, time lag between scientific discovery and technological applications and technology spillover from military to civilian area are the economic lessons learnt from the story of cellular origin.

The Digital Age of Mobile Cellular Network in Germany and China:Policies,Technologies and Markets (Part Ⅱ)

The German Postal Reform I in 1989 introduced competition in the mobile cellular market. German cellular operators, DeTeMobil, Mannesmann, E-Plus and VIAG Interkom, built D1-, D2-, E1-and E2-Netze based on GSM standards made in Europe. China Unicom was created in 1994 and China Telecom was separated from MPT in 1995. China Telecom and China Unicom competed in a duopoly from the mid-1990s onwards and the cellular services provided by them also rely on GSM standards. China Telecom additionally deployed XLT technology (PHS) from the late 1990s onwards. While DeTeMobil and Mannesmann conquered approximately 80%-90% of the market throughout the 1990s and were the two dominant market players in Germany, China's cellular market was mainly controlled by China Mobile. In Germany, prices related to cellular technology continued the downwards trend as a major result of the process of deregulation, liberalisation and competition. In China, price wars had led to significant price reductions in the cellular market. Although network operators in both countries strived to deliver differentiated cellular services, the two national markets in the 1990s were visibly shaped by product homogeneity.

装配干扰的控制──Fuzzy-Petri网络系统帮助调整装配计划

复杂产品单件或小批量装配的流程，经常会受到许多干扰的影响。因此，装配管理人员必须使根据生产能力得出的中期装配计划不断更新，适应实际的装配流程，以确保达到预期的生产目标。一种干扰管理系统已经投入使用，以支持对生产有影响的决策。这一系统目前在克姆尼茨工业大学和亚深工业大学机床和企业管理实验室（WZL）的合作下应运而生。为了制定现行的装配计划，采用了以Fuzzy－Petri网络为知识基础的专家系统，该系统运用了模糊表达的技术经验，能确保决策与实际情况相符合。