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41.
根据勘测设计的行业特点,提出勘测设计单位应采用面向工程的以设计流程为核心的PDM系统,来缩短设计周期,提高设计质量。对PDM的设计应遵循和实现的系统目标、设计原则、系统体系结构、系统基本功能以及PDM的应用实施做了阐述。 相似文献
42.
A study, comparing the effect of blowing agent selection on energy consumption and the life cycle climate performance (LCCP) of a typical European refrigerator is discussed. Energy consumption of prototype European-style refrigerators made with a foam formulation with HFC-245fa as the blowing agent was measured and compared with energy consumption of the same model as currently produced (using a foam with a pentane blend for the blowing agent). Results were used in a LCCP study, considering both direct and indirect climate impacts due to blowing agent emissions and energy consumption in manufacturing processes and over the life cycle of the refrigerator. An assumption is made that the refrigerator is built and used in the European market. 相似文献
43.
Since its inception of just over two decades ago, the World Wide Web has become a truly ubiquitous and transformative force in our life, with millions of Web applications serving billions of Web pages daily. Through a number of evolutions, Web applications have become interactive, dynamic and asynchronous. The Web׳s ubiquity and our reliance on it have made it imperative to ensure the quality, security and correctness of Web applications. Testing is a widely used technique for validating Web applications. It is also a long-standing, active and diverse research area. In this paper, we present a broad survey of recent Web testing advances and discuss their goals, targets, techniques employed, inputs/outputs and stopping criteria. 相似文献
44.
This paper presents the results of the OEPM (Spanish Patent and Trademark Office)/OECD (Organisation for Economic Co-operation and Development) survey on the economic and financial uses of patents carried out in 2008 among Spanish business applicants of OEPM patents. It also summarizes evidence from previous surveys. All available information indicates that only a few Spanish firms holding patents license them out. Results from the OEPM/OECD survey also reveal that obtaining public support is the first financial use of patents for Spanish firms. Responses to the same OECD questionnaire by EPO patent applicants from several European countries are quite different: licensing out is an extended practice among EPO patent holders from different countries, including Spain, and convincing venture capitalists and private investors are their two most important financial uses of patents. In our view this suggests that there are significant differences across European countries as regards the development of national technology markets and results from international surveys are driven by responses from the largest and more developed countries. The drivers and actors in markets for patents that only protect inventions nationally may be quite distinct from those in markets for patents that protect inventions regionally, such as EPO patents within Europe. 相似文献
45.
Control loop performance monitoring (CPM) in industrial production processes is an established area of research for which many methods to detect malfunctioning loops have been developed. However, it is unclear which methods are successful in an industrial environment. Often, there are additional aspects such as organizational issues, data availability and access that can compromise the use of CPM. In this paper, we are reporting on the results of a survey amongst CPM users. The survey takes stock of existing methods and their use in industry as well as which faults are most frequent and can be detected. Organizational as well as implementation issues are investigated and discussed. This paper aims to identify open research topics and the direction of development of CPM in industrial production processes. 相似文献
46.
《Ergonomics》2012,55(9):1312-1321
Following a brief review of the principal clinical characteristics of musculoskeletal disorders of the upper limbs, the authors propose a protocol for a structured anamnestic examination featuring a series of set questions. The anamnestic model is based on a detailed listing of the symptoms to be analysed, which are divided into four categories: pain, paraesthesia, symptoms attributable to hyposthenia, and neurovegetative disorders. Regarding pain and paraesthesia, the authors list the localization, pattern of onset, duration and number of episodes, irradiation and treatment. The patients can thus be classified as anamnestic cases based on the following criteria: presence of pain or paraesthesia during the last 12 months, with episodes lasting for at least 1 week or occurring at least once a month, with no previous acute trauma. For hyposthenia, the authors report on the conditions under which the disorder may develop. The neurovegetative disorders considered are modifications in colour of the fingers and reaction to exposure to low temperatures. The structure of the proposed anamnestic chart permits all findings to be easily encoded for subsequent storage in a dedicated database. The appendix contains an annotated facsimile of the anamnestic chart. 相似文献
47.
José Ignacio Gimenez-Nadal José Alberto Molina Jorge Velilla 《Papers in Regional Science》2019,98(4):1667-1684
The research on commuting has emerged in recent decades, but the issue of whether the empirical techniques used are appropriate has not been analysed. Thus, results from prior research could be based on non-accurate models, leading to misleading conclusions. We apply an algorithmic approach based on bootstrapping, variable selection, and mean absolute prediction errors, which is designed to avoid overfitting. Using the American Time Use Survey, we find that models with a reduced set of explanatory variables have similar accuracy to standard econometric models. Our results shed light on the importance of determining whether models can be overfitted. 相似文献
48.
El‐Hajjaji Soundous Grard Amaury De Laubier Juliette Di Tanna Sybille Lain Aurlie Patz Viviane Sindic Marianne 《International Journal of Dairy Technology》2019,72(3):466-471
This study aims to describe the procedures and practices used in local production of raw milk butter. The demand for local products is increasing; hence, there is a need to describe the practices used in the artisanal production of raw milk butter. Therefore, a survey of 147 raw milk butter producers was carried out. The results from the survey indicate that there is not one single way to produce butter at artisanal level. In terms of maturation, six temperature sequences were distinguished. Attention is required at every step of production starting from breeding. 相似文献
49.
《Information & Management》2016,53(3):398-408
Open innovation and business process innovation (BPI) have been investigated by their respective research communities for decades. However, the important relationship between externally focused open innovation and internally implemented BPI is currently unexplored, particularly in transition economies. The main purpose of this study is to contribute toward closing this important research gap. This study describes the main findings of a research study of innovation practices of 224 companies operating in a transition economy.We propose and validate a comprehensive model of integrative innovation and offer some important insights into the relationship between externally focused R&D collaboration and a firm's internal process innovation. 相似文献
50.
Understanding human motivations and actions related to environmental problems is central to modeling complex, human-natural systems. However, social science survey data on environmental issues are often presented in relatively static reports and figures and are not easily accessible for participatory deliberation. Federal data sharing mandates motivate innovative data visualization and sharing mechanisms. We developed an open-source, web-based Survey Data Viewer as a visual interface to explore quantitative social science survey data. We used the Python Django web framework and the D3.js visualization library to create and deploy the tool. The Viewer was implemented using a water-related survey administered to a large, random sample of Utah adults in public venues. The Viewer allows users to visualize question responses based on demographic variables with percentages and mean response levels. We developed a standardized template for encoding survey data and metadata that permits the generalization of the tool to other similar surveys. 相似文献