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991.
The purpose of this study was to discover whether there are scholarly evaluation metrics that can be applied to a wide range of books’ types and contents. We analyzed over 70,000 books and collected various metrics per each title including traditional and altmetrics measures. The analysis in this paper depicts the top books showing the highest rates of citations, reviews, readership, downloads, twitter and more. Our results show that books display different impact in each of the measurements and vary by types and content. There isn’t one measure that captures the impact of books across the board. We conclude that books should be evaluated by types and contents while using different measures per each.  相似文献   
992.
This essay provides an unpalatable perspective on classifying the reluctance of authors, editors or publishers to correct their erroneous literature as being unethical. Authors who publish papers that carry errors and who take laurels for such publications, but who then fail to correct reported errors at a post-publication stage should be classified as unethical, and their act or irresponsibility as misconduct. Similarly, editors and publishers who fail to revise erroneous literature when claims are factually correct, independent of the volume of claims, are also in violation of their codes of conduct and professional responsibilities towards the scientific community and society. This essay provides a critical outlook on this issue which has begun to plague the post-publication movement in science, and which deserves urgent attention and focus.  相似文献   
993.
It has been shown that accessing the patients’ own electronic health records (EHR) can enhance their medical understanding and provide clinically relevant benefits. However, languages that are difficult for non-medical professionals to comprehend are prevalent in the EHR notes. The valuable and authoritative information contained in the EHR is thus less accessible to the patients, who ultimately stand to benefit the most from the information. To address this challenge, we are developing a system to retrieve EHR note-specific online consumer-oriented health education materials. We explored several query generation methods to convert long EHR notes to effective queries, including topic models and key concept identification. Our experiments show that queries using key concepts identified by a learning based model with pseudo-relevance feedback significantly outperform the baseline system of using the full text note.  相似文献   
994.
Evaluation of search engines relies on assessments of search results for selected test queries, from which we would ideally like to draw conclusions in terms of relevance of the results for general (e.g., future, unknown) users. In practice however, most evaluation scenarios only allow us to conclusively determine the relevance towards the particular assessor that provided the judgments. A factor that cannot be ignored when extending conclusions made from assessors towards users, is the possible disagreement on relevance, assuming that a single gold truth label does not exist. This paper presents and analyzes the predicted relevance model (PRM), which allows predicting a particular result’s relevance for a random user, based on an observed assessment and knowledge on the average disagreement between assessors. With the PRM, existing evaluation metrics designed to measure binary assessor relevance, can be transformed into more robust and effectively graded measures that evaluate relevance towards a random user. It also leads to a principled way of quantifying multiple graded or categorical relevance levels for use as gains in established graded relevance measures, such as normalized discounted cumulative gain, which nowadays often use heuristic and data-independent gain values. Given a set of test topics with graded relevance judgments, the PRM allows evaluating systems on different scenarios, such as their capability of retrieving top results, or how well they are able to filter out non-relevant ones. Its use in actual evaluation scenarios is illustrated on several information retrieval test collections.  相似文献   
995.
Implementation of ecological migration (eco-migration) policies may improve the fragile ecological environment of emigration areas; however, it also places enormous pressure on the human-environment systems in immigrant resettlement regions. Via the application of participatory rural appraisal (PRA) methods, ecological footprint (EF), and stochastic impacts by regression on population, affluence, and technology (STIRPAT) models, 21 villages of Huanjiang County in Guangxi Zhuang Autonomous Region, China were used in this research as a case study area for the environmental appraisal of eco-migration policies in immigrant resettlement regions. Results show: (1) In the past 20 years of implementing eco-migration policies, the EF per capita constantly increased, the biocapacity (BC) per capita constantly decreased, and the ecological deficit gradually increased, indicating an extremely negative impact of eco-migration projects on the ecological environment in the immigration areas. (2) Cropland and forest land are the most important components of the per-capita EF. The per-capita EF of cropland experienced overall a first increasing and then decreasing trend, and the per-capita EF of forest land constantly increased and showed the most rapid increase among all types of EF in the last two decades. (3) The proportion of per-capita EF of different types of productive land is in the order of forest land > cropland > carbon uptake land > built-up land > grazing land from high to low, and this is a significant change from the original order of cropland > forest land > carbon uptake land > grazing land > built-up land. (4) Because of unequal possession of ecologically productive resources, the overall per-capita EF, overall per-capita BC, overall per-capita ecological deficit of productive land use by migrants, and their component values of different types of productive land use are all lower than the corresponding values of the natives. The ecological deficit of natives is more severe than that of migrants. (5) Whereas population growth and overexploitation of resources lead directly to the increased pressure on the ecological environment in the immigration areas, increasing nonagricultural income and improving the consumption structure can reduce the dependence of farmers on the land, thus inhibiting the increase of EF.  相似文献   
996.
1 Introduction PlanardevelopmentofacurvedsurfaceisbroadlyusedinCAGDandCAD .Accordingtotheirdevelop ment ,surfacesaredividedintodevelopablesurfacesandnon developablesurfaces .Mostofcurvedsurfacesarenon developable ,butbroadlyusedinengineering ,suchasaircraftwings ,laminaofturbine ,fluidsur face .Howeverthedesignandhandlingofcurvedsur faceareverydifficult.Inordertopredigestthecom plexityofdesign ,planardevelopingisintroduced .Non developablesurfacescannotbedevelopedontoaplanewithoutstretch…  相似文献   
997.
A double photodiode (PD) constructed by p+/N-well junction and N-well/p-sub junction was designed and fabricated in a UMC 0.18-μm CMOS process. Based on the device structure and mechanism of double PD, a novel small-signal equivalent circuit model considering the carrier transit effect and the parasitic RC time constant was presented. By this model with complete electronic components, the double PD can be incorporated in a commercial circuit simulator. The component values were extracted by fitting the measured S-parameters using simulated annealing algorithm, and a good agreement between the measurement and the simulation results was achieved.  相似文献   
998.
The identification and use of molecular biomarkers have greatly improved the diagnosis and treatment of malignant tumors. However, a much deeper understanding of oncogenic proteins is needed for the benefit to cancer patients. The lipid raft marker proteins, flotillin-1 and flotillin-2, were first found in goldfish retinal ganglion cells during axon regeneration. They have since been found in a variety of cells, mainly on the inner surface of cell membranes, and not only act as a skeleton to provide a platform for protein–protein interactions, but also are involved in signal transduction, nerve regeneration, endocytosis, and lymphocyte activation. Previous studies have shown that flotillins are closely associated with tumor development, invasion, and metastasis. In this article, we review the functions of flotillins in relevant cell processes, their underlying mechanisms of action in a variety of tumors, and their potential applications to tumor molecular diagnosis and targeted therapy.  相似文献   
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