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排序方式: 共有2068条查询结果,搜索用时 15 毫秒
91.
This paper introduces a methodology for the construction of a country level patent value indicator based on the family size of a country’s patent profile at the level of technology fields. Because individual family members target different markets and technologies have a different propensity to internationalization, family size has been shown to have a restricted power to assess the quality of patent profiles of countries. We address this gap by weighting the members of patent families filed at different patent offices before calculating the family size indicators, to account for the market potential in which the patents of these families were filed. We apply different weighting schemes and test which scheme is best able to explain the export performance of countries. In order to conduct our analyses, a panel dataset, consisting of annual data (1990–2002) on international trade from the UN-COMTRADE database and patent data from the “EPO Worldwide Patent Statistical Database” (PATSTAT), was compiled. Several bivariate analyses reveal that weighted and unweighted family counts are highly correlated, meaning that statistics based on absolute (weighted or unweighted) family counts are barely affected by the chosen weighting factor. This, however, is different when using the average family size, where weighting the family members by imports, as well as GDP, can be shown to have a robust positive effect to explaining export performance. The imports and the GDP weighted average family size are thus able to act as a consistent indicator of patent value at the country and technology field level. 相似文献
92.
Optimization of simulation model output is one of the most important tasks in a simulation study of a complex system. Efficacy of an optimization approach is expressed in the accuracy of locating a global extremum, as well as in the number of investigated search points. The approach Machine Learning Optimization (ML-Opt), presented in this article, explores functional dependencies between search points in order to reduce the number of evaluations. Functional relations between search points are determined by an inductive learning algorithm, which generates a classifier used as a control structure in the optimization process. The classifier approximates the structure of the unknown goal function given by a simulation model and affects the generation of new search points. A discussion of a numerical example concludes the paper. 相似文献
93.
94.
Mag. Christian Rainer 《BHM Berg- und Hüttenm?nnische Monatshefte》2013,158(7):294-296
On the occasion of the 50th anniversary, the contributions of the Department of Economic and Management Sciences (WBW), University of Leoben, to the development of logistics in research and education are highlighted. After a discussion of the milestones of logistics and related dissertations of the department WBW, the newly resulting curriculum is presented. The paper concludes with an outlook on a possible new research topic. 相似文献
95.
Romero-Canyas Rainer; Downey Geraldine; Reddy Kavita S.; Rodriguez Sylvia; Cavanaugh Timothy J.; Pelayo Rosemary 《Canadian Metallurgical Quarterly》2010,99(5):802
Societies and social scientists have long held the belief that exclusion induces ingratiation and conformity, an idea in contradiction to robust empirical evidence linking rejection with hostility and aggression. The classic literatures on ingratiation and conformity help resolve this contradiction by identifying circumstances under which rejection may trigger efforts to ingratiate. Jointly, findings from these literatures suggest that when people are given an opportunity to impress their rejecters, ingratiation is likely after rejection experiences that are harsh and that occur in important situations that threaten the individual's self-definition. Four studies tested the hypothesis that people high in rejection sensitivity and therefore dispositionally concerned about rejection will utilize opportunities to ingratiate after harsh rejection in situations that are self-defining. In 3 studies of situations that are particularly self-defining for men, rejection predicted ingratiation among men (but not women) who were high in rejection sensitivity. In a 4th study, harsh rejection in a situation particularly self-defining for women predicted ingratiation among highly rejection-sensitive women (but not men). These findings help identify the specific circumstances under which people are willing to act in socially desirable ways toward those who have rejected them harshly. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
We outline a model for security investment that reflects dynamic interaction between a defender, who faces uncertainty, and an attacker, who repeatedly targets the weakest link. Using the model, we derive and compare optimal security investment over multiple periods, exploring the delicate balance between proactive and reactive security investment. 相似文献
97.
Jegatheswaran Ratnasingam Rainer Grohmann Frieder Scholz 《Holz als Roh- und Werkstoff》2010,5(2):115-116
In this study, the kiln drying yield of 30 mm Rubberwood (Hevea brasiliensis)
used for the furniture manufacturing industry in South East Asia was evaluated. The results showed that
the average yield loss was 10%, and end-checks, splits and warping were the most common drying defects.
It was found that sawn timber from older trees (> 21 years) were less prone to drying defects,
and the use of stress relieving treatments significantly reduced the incidence of drying defects. 相似文献
98.
Chloride‐induced damage of reinforcing steel is especially for parking garages and bridges often very severe as large amounts of chlorides act on horizontal surfaces which could lead to fast ingress of these detrimental ions up to the level of the reinforcement and subsequently to high rates of corrosion. In order to avoid the disadvantages of conventional rehabilitation (unreliable prognosis with patch repair or high costs and regular maintenance with cathodic protection using impressed current) a new combined protection system was developed where the principle of drying out the concrete (by means of a surface protection system) is combined with a temporary cathodic protection (by means of a sprayed zinc layer) during the transitional period of the drying out process. This new system was tested both in the laboratory and on‐site at a pilot application. Based on the results obtained the possibilities and limitations of the new system are discussed in this paper. 相似文献
99.
100.
This paper considers the inverse 1-center location problem with edge length augmentation on a tree network T with n + 1 vertices. The goal is to increase the edge lengths at minimum total cost subject to given modification bounds such that
a predetermined vertex s becomes an absolute 1-center under the new edge lengths. Using a set of suitably extended AVL-search trees we develop a combinatorial algorithm
which solves the inverse 1-center location problem with edge length augmentation in O(n log n) time. Moreover, it is shown that the problem can be solved in O(n) time if all the cost coefficients are equal. 相似文献