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101.
Low- and high-frequency measurements are presented of five differently shaped targets: the NASA almond, ogive, double ogive, cone-sphere, and cone-sphere with gap. These were measured from 700 MHz to 16 GHz. The metallic targets are made of aluminum, and were cut by a numerically controlled mill to maintain the surface precision. Except for the almond target, all the targets were made in two parts and joined by sleeves and screws. The measurements are computational electromagnetics (CEM) validation measurements for the Electromagnetic Code Consortium (EMCC)  相似文献   
102.
Modular product architectures are used by many firms today to achieve a high degree of product differentiation whilst reducing cost through economies of scale. At the same time, the firms are increasing architecture lifetimes to 10 years or more, which brings up new challenges for the development process. Uncertainties regarding future product features need to be anticipated when designing the architecture to minimize modification efforts. Nevertheless, existing approaches for designing modular product architectures are mainly based on static requirements and thereby neglect the dynamics of the market that influence future product features. This paper aims at presenting a method utilizing scenario-planning and simulations in the product range planning process to determine future product features and their uncertainties as a basis for the product architecture design. Possible feature specifications are derived from product environment scenarios and linked to the factors influencing the scenarios, to calculate their expected values and deviations.  相似文献   
103.
104.
Companies in high wage countries are increasingly confronted with the challenge of optimizing economies of scope and economies of scale simultaneously to succeed on a global market place. An integrated assessment of production systems facing this challenge is essential to evaluate the actual state of a company and to provide a basis for drawing the right conclusions to reconfigure production systems successfully. In this paper an integrated model for measuring economies of scope as well as economies of scale is introduced, defining the fundamental domains of a production system. The major objectives resulting from the overall scale-scope dilemma are broken down for each domain and the main dimensions for an assessment of each domain are defined. A new measure named Degree of Efficiency is defined, quantifying the fulfillment of the opposing objectives in each domain and hence, the contribution to an overall resolution of the scale-scope dilemma.  相似文献   
105.
Twenty-eight iron isotopes have been observed so far and the discovery of these isotopes is discussed here. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.  相似文献   
106.
Production of Sterols from Residues of Fat-Splitting Sterols are enriched in distillation residues of fat-splitting and fat-transesterification (with methanol); they are biotechnologically interesting starting materials. Possibilities for further concentrating the sterols are described.  相似文献   
107.
108.
Increase of Internet traffic and introduction of triple-play services force operators to increase network capacity at moderate costs. Introduction of higher electronic time-division multiplexing (ETDM) channel bit rate targets reduce the cost per bit for the transmission due to lower power consumption, smaller footprint, less management effort, and complexity of the systems. Improved performance of electronic and optoelectronic components allows for research on ETDM bit rates beyond 40 Gb/s, which is currently the highest standardized channel bit rate for optical telecommunication networks. In this paper, an overview of recent progress in high-speed ETDM technology for 80 Gb/s and beyond and results of high-speed ETDM transmission experiments are given. Currently, the speed of electronics enables ETDM systems with line rates of 80/85 Gb/s and even 100 Gb/s, which is expected to be the next generation of Ethernet in data communication  相似文献   
109.
Piezoelectric ceramics based on the perovskite Pb(Zr,Ti)O3 (PZT) system are widely used as sensors and actuators. The toxicity of lead has motivated research in the field of alternative environmentally friendly lead-free materials. Lead-free piezoelectric ceramics are numerous and in comparison to PZT poorly investigated. The performance of PZT cannot yet be achieved by any lead-free material. Thus High Throughput Experimentation (HTE) shall be applied to discover new lead-free piezoelectric ceramics. In the present study a parallel solid state synthesis method was established for bulk ceramics. Libraries consisting of chemically diverse oxides are produced via the mixed-oxide route. Subsequently, classical piezoelectric parameters such as ɛ, d33 and Curie temperature are screened. The high throughput route, which allows the synthesis and characterisation of over one hundred samples per week, has to be validated with PZT samples. The morphotropic phase boundary was clearly identified and dielectric measurement shows excellent results. The method may be extended to lead-free materials.  相似文献   
110.
Individual monitoring regulations in Switzerland are based on the ICRP60 recommendations. The annual limit of 20 mSv for the effective dose applies to the sum of external and internal radiation. External radiation is monitored monthly or quarterly with TLD, DIS or CR-39 dosemeters by 10 approved external dosimetry services and reported as H(p)(10) and H(p)(0.07). Internal monitoring is done in two steps. At the workplace, simple screening measurements are done frequently in order to recognise a possible incorporation. If a nuclide dependent activity threshold is exceeded then one of the seven approved dosimetry services for internal radiation does an incorporation measurement to assess the committed effective dose E(50). The dosimetry services report all the measured or assessed dose values to the employer and to the National Dose Registry. The employer records the annually accumulated dose values into the individual dose certificate of the occupationally exposed person, both the external dose H(p)(10) and the internal dose E(50) as well as the total effective dose E = H(p)(10)+E(50). Based on the national dose registry an annual report on the dosimetry in Switzerland is published which contains the statistics for the total effective dose, as well as separate statistics for external and internal exposure.  相似文献   
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