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991.
The Office of Technology Assessment (OTA), which was created by the Technology Assignment Act of 1972, was—and still remains even after its abolishment in 1995—a unique congressional agency. OTA provided members of Congress with their own means of understanding and evaluating complex science and technology matters—of which there are no shortages. It spurred an entire literature of academic research both about OTA and the idea of technology assessment more generally. Understanding the legislative history and implementation of the Technology Assessment Act is crucial not just for scholarship, though. OTA was a blueprint for institutionalizing politically accountable technology assessment. Even as technologies advance at rapid rates, OTA still offers valuable lessons that scholars and policy-makers alike ought to glean. This paper places OTA in a contemporary context of (institutionalized) technology assessment. It contributes to a better understanding of OTA's origins by tracing its lineage to a set of federal reports beginning in 1929. It then analyzes OTA's response to pragmatic implementation questions of how to strike a balance between speed, depth, scope, and temporal focus. Lastly, it uses a public values framework to critique OTA's failure to adequately incorporate participatory elements into its processes.  相似文献   
992.
We will consider a convex subset of a metric linear space and a certain group of actions G on this set, that allow us to define the notion of Haar zero measure on sets that have zero Haar measure for the translation (by adding) invariant HSY prevalence theory. In this way, we will be able to define the meaning of G-prevalent set according to the pioneering work of Christensen. Our setting considers problems which take into account the convex structure and this is quite different from the previous results on prevalence which consider basically the linear additive structure. In this setting, we will show a kind of quantitative Kupka–Smale theorem, and also we generalize a result about rotation numbers which was first considered by J.-C. Yoccoz (and, also by M. Tsujii). Among other things we present an estimation of the amount of hyperbolicity in a setting that we believe was not considered before.  相似文献   
993.
994.
Standard enthalpies of formation of selected ternary Pd-based Heusler type compositions Pd2YZ (Y = Cu, Hf, Mn, Ti, Zr; Z = Al, Ga, In, Ge, Sn) were measured using high temperature direct synthesis calorimetry. The measured enthalpies of formation (in kJ/mole of atoms) of the Heusler compounds are, Pd2HfAl (−81.6 ± 2.4); Pd2HfGa (−79.9 ± 2.9); Pd2HfIn (−76.4 ± 1.4); Pd2HfSn (−77.6 ± 1.6); Pd2MnSn (−54.6 ± 3.1); Pd2TiGa (−65.6 ± 3.6); Pd2TiIn (−69.9 ± 2.1); Pd2TiSn (−78.6 ± 2.4); Pd2ZrAl (−85.3 ± 3.0); Pd2ZrGa (−76.2 ± 1.9); Pd2ZrIn (−85.1 ± 3.9); Pd2ZrSn (−92.2 ± 3.1); for the B2 compounds, Pd2MnAl (−87.1 ± 3.0); Pd2MnGa (−54.5 ± 1.7); Pd2MnIn (−41.0 ± 2.5); Pd2TiAl (−81.4 ± 1.9); for the tetragonal compound Pd2CuAl (−55.2 ± 3.0) and for the orthorhombic compound Pd2CuSn (−43.1 ± 2.3). Values were compared with those from published first principles calculation and the Open Quantum Materials Database (OQMD). Lattice parameters of these compounds were determined by X-ray diffraction analysis (XRD). Microstructures were identified using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Selected alloys were annealed at various temperatures to investigate phase transformations and phase relationships.  相似文献   
995.
上海石化0.4 Mt/a PTA装置扩产改造中,TJ-302氧化母液罐处理量不能满足需求,需要大幅度加快循环速度,在原有设备上增设搅拌器是最经济的选择。增设搅拌器后,又出现新问题,由于循环速度加快,设备中原有的固体含量增加,必须进行再改造。经充分的分析研究以及计算,增设了罐内轴滑动轴承,从而解决了上述问题。  相似文献   
996.
For the United States Nuclear Regulatory Commission and the reactor licensees it regulates, there are a number of contemporary issues associated with the back end of the fuel cycle including, the agency's revision to its “Waste Confidence” decision and the path-forward for high-level waste disposal. Additionally, the 2012 Blue Ribbon Commission on America's Nuclear Future recommendations, the future of reprocessing, consolidated interim spent fuel storage, and maintaining technical competence within the NRC in challenging budgetary conditions are addressed. I conclude that there is confidence in the feasibility of safe storage of spent nuclear fuel following the licensed operational life of a reactor and any change in high-level waste policy will require Congressional action to amend the Nuclear Waste Policy Act.  相似文献   
997.
The paper is mainly to explore the automated music composition experiences for the students in the high grades of elementary school who are unfamiliar with the professional music theory. The proposed Automated Composition for Music Education (ACME) software was developed to help the students to compose the rhythm and melody themselves, while chord configuration and arrangement are automatically generated. Subsequently, sixth-year students of a non-experimental school were recruited to use the software for the completion of its development. Analysis of learning effectiveness at the reaction level, analysis of learning-level learning effectiveness, correlation analysis of the reaction- and learning-levels learning effectiveness has been performed with a significant result. The correlations between each component of learning effectiveness at the reaction and learning levels were also found. Finally the students in the experimental group using the ACME teaching materials showed a better learning effectiveness at both reaction level and learning level, than those of the students in the comparison group.  相似文献   
998.
当前治理汽车尾气污染的最好方法是采用含有贵金属的三元催化剂同时对NOx、HC、CO进行处理.催化转化器的结构性能直接影响催化效率的高低,准确测定及鉴定催化剂中主要部件的结构性能指标就具有重要意义.该文利用X-射线衍射光谱仪(XRD)、扫描电子显微镜能谱分析技术(SEM-EDS)以及等温液氮吸附-脱附技术对6种使用过的和未使用过的机动车尾气三元催化剂的结构性能进行分析研究.结果表明:可以通过X-射线衍射光谱仪区分各催化剂载体的材质,文中样品经鉴定都为堇青石陶瓷蜂窝载体,不同催化剂的比表面积和孔容存在差异;通过扫描电子显微镜可以观察到催化剂载体表面涂层的微观结构,及一些催化剂载体表面涂层出现的裂纹;通过能谱分析各载体主要元素的大致含量.  相似文献   
999.
The determinants of the premium value of patents for medical and cosmetic products are analyzed with respect to a complementary IP strategy such as trademarks. I discuss a novel method and database to gauge combinations of patent and trademark pairs regarding the same innovative project. The premium value is computed through a model of renewal decisions for the patent cohorts 1985–1990 that have been designated in the U.K. and Germany. After taking into the account several firm characteristics and patent indicators typically used in the literature, I find ample evidences that patent and trademark pairs are featured by higher valuations.  相似文献   
1000.
This research is concerned with the problem of 4 degrees of freedom (DOF) ship manoeuvring identification modelling with the full-scale trial data. To avoid the multi-innovation matrix inversion in the conventional multi-innovation least squares (MILS) algorithm, a new transformed multi-innovation least squares (TMILS) algorithm is first developed by virtue of the coupling identification concept. And much effort is made to guarantee the uniformly ultimate convergence. Furthermore, the auto-constructed TMILS scheme is derived for the ship manoeuvring motion identification by combination with a statistic index. Comparing with the existing results, the proposed scheme has the significant computational advantage and is able to estimate the model structure. The illustrative examples demonstrate the effectiveness of the proposed algorithm, especially including the identification application with full-scale trial data.  相似文献   
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