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191.
Tausch Nicole; Becker Julia C.; Spears Russell; Christ Oliver; Saab Rim; Singh Purnima; Siddiqui Roomana N. 《Canadian Metallurgical Quarterly》2011,101(1):129
A recent model of collective action distinguishes 2 distinct pathways: an emotional pathway whereby anger in response to injustice motivates action and an efficacy pathway where the belief that issues can be solved collectively increases the likelihood that group members take action (van Zomeren, Spears, Fischer, & Leach, 2004). Research supporting this model has, however, focused entirely on relatively normative actions such as participating in demonstrations. We argue that the relations between emotions, efficacy, and action differ for more extreme, nonnormative actions and propose (a) that nonnormative actions are often driven by a sense of low efficacy and (b) that contempt, which, unlike anger, entails psychological distancing and a lack of reconciliatory intentions, predicts nonnormative action. These ideas were tested in 3 survey studies examining student protests against tuition fees in Germany (N = 332), Indian Muslims' action support in relation to ingroup disadvantage (N = 156), and British Muslims' responses to British foreign policy (N = 466). Results were generally supportive of predictions and indicated that (a) anger was strongly related to normative action but overall unrelated or less strongly related to nonnormative action, (b) contempt was either unrelated or negatively related to normative action but significantly positively predicted nonnormative action, and (c) efficacy was positively related to normative action and negatively related to nonnormative action. The implications of these findings for understanding and dealing with extreme intergroup phenomena such as terrorism are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
192.
Yeon Soon Jung Gain You Ho Sik Shin Hark Rim 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):104-112
We examined the relationships between Geriatric Nutritional Risk Index (GNRI), total lymphocyte count (TLC), and mortality in hemodialysis (HD) patients. We examined GNRI and TLC in 120 maintenance HD patients and followed these patients for 120 months. Predictors of all‐cause death were examined using life table analysis and the Cox proportional hazards model. TLC marginally correlated with GNRI (r = 0.176; p = 0.090) and significantly with phosphorus levels (r = 0.206; p = 0.026). Life table analysis revealed that subjects with a GNRI < 90 (n = 19) had lower survival rates than did those with a GNRI ≥ 90 (n = 101; Wilcoxon's test, p = 0.048), but subjects with a TLC < 1500/mm3 (n = 76) had similar survival rates compared with subjects with a TLC ≥ 1500/mm3 (n = 44; Wilcoxon's test, p = 0.500). Multivariate Cox proportional hazards analyses demonstrated that GNRI is a significant predictor of mortality (hazard ratio 9.315, 95% confidence interval 1.161–74.753, p = 0.036), after adjusting for age, sex, presence of type 2 diabetes mellitus, Kt/V, normalized protein catabolic rate, hematocrit, phosphorus, systolic blood pressure and TLC. Our findings suggest the TLC may be used as a simple nutritional tool, but may not be a predictor of mortality in HD patients. These findings require confirmation by further studies. 相似文献
193.
New low-band-gap copolymers, including thieno[3,2-b]thiophene and 2,1,3-benzothiadiazole, were synthesized as photovoltaic materials. Thiophene was introduced to provide extended π-conjugation length and charge transfer properties. A band gap (Egop=1.62 eV, Egec=1.51 eV) of this polymer was investigated through UV-vis spectroscopy and cyclic voltammetry. A bulk heterojunction structure of glass/indium tin oxide (ITO)/PEDOT:PSS/polymer-PCBM(1:3)/LiF/Al was fabricated for investigating photovoltaic properties. PC71BM was used as an acceptor material, due to its increased absorption in the visible region, in comparison with PC61BM. In this polymer, incident photon-to-current conversion efficiency (IPCE) was as high as 50%. Moreover, maximum power conversion efficiency (PCE) of up to 1.72% was achieved under AM 1.5 G conditions. It demonstrated relatively high VOC (0.67 V) and JSC (6.86 mA/cm2), while a low fill factor value (0.37) was obtained. 相似文献
194.
Sang-Mo Kim You-Seung Rim Min-Jong Keum Kyung-Hwan Kim 《Journal of Electroceramics》2009,23(2-4):341-345
Transparent conductive oxide (TCO) thin films such as tin doped indium oxide (ITO), zinc doped indium oxide (IZO) and Al doped zinc oxide (AZO) have been widely used as transparent electrode for display. ITO and AZO thin films for display was prepared by the facing targets sputtering (FTS) system. The FTS method is called a plasma-free sputter method because the substrate is located apart from plasma. This system can deposit the thin film with low bombardment by high energetic particles in plasma such as γ-electrons, negative ions and reflected Ar atoms. ITO and AZO thin films were deposited on glass substrate at room temperature with oxygen gas flow rate and input power. And the electrical, structural and optical properties of the thin films were investigated. As a result, the resistivity of ITO, AZO thin film is 6?×?10?4 Ω cm, 1?×?10?3 Ω cm, respectively. And the optical transmittance of as-deposited thin films is over 80% at visible range. 相似文献
195.
One of the ubiquitous technology fields that have received the most attention recently from technology communities worldwide is mobile radio frequency identification (RFID). Mobile handsets loaded with RFID readers enable the identification and retrieval of information on RFID tagged objects. In Korea, a variety of mobile RFID services are currently being piloted, and their commercial roll‐out looks imminent. The goal of this study is to propose, ahead of the commercial launch of mobile RFID services, a customer satisfaction index (CSI) model for this service category and to then measure the CSI to derive practical implications for their providers and pointers related to the improvement of service. A web survey was conducted on Korean mobile phone subscribers who had participated in a mobile RFID pilot program. Using the results of this survey, we tested the CSI model and its hypotheses by employing a partial least‐squares‐based structural equation model analysis and calculated the index. We further conducted an importance‐performance analysis in order to provide insights that may be useful for improving the quality of mobile RFID services. 相似文献
196.
Lee SJ Koo JR Shin HS Kim BY Park HR Kim YK Ha Y 《Journal of nanoscience and nanotechnology》2012,12(7):5418-5422
Highly efficient blue phosphorescent organic light-emitting diodes are investigated using iridium(Ill) bis[(4,6-di-fluorophenyl)-pyridinato-N,C2']picolinate doped in N,N'-dicarbazolyl-3,5-benzene (mCP) with a charge control layer (CCL) as the dual recombination zone (DRZ) system. DRZ with CCL was used to form a broad recombination zone and exciton confinement within each emission zone. Holes and electrons can be easily transported through the CCL, which were a mixed p-type mCP and n-type 2,2',2"-(1,3,5-benzenetryl) tris(1-phenyl)-1H-benzimidazol, for controlling the carrier movement. The CCL can play a role in triplet exciton blocking as expected from high triplet energy levels as well. Additionally, a white organic light-emitting diode was fabricated using a new phosphorescent orange emitter: bis[2-(2,4-difluorophenyl)pyridinato]iridium 2-(2-hydroxyphenyl)benzothia zolate doped in DRZ. The white device showed a maximum luminous efficiency of 23.15 cd/A, a maximum external quantum efficiency of 9.56%, and a maximum power efficiency of 13.37 lm/W. It also showed white emission with CIEx,y coordinates of (x = 0.33, y = 0.41) at 8 V. 相似文献
197.
Tae Rim Park Kyung-Joon Park Myung J. Lee 《Wireless Communications, IEEE Transactions on》2009,8(11):5530-5541
In wireless sensor networks, scheduling the sleep duration of each node is one of the key elements for controlling critical performance metrics such as energy consumption and latency. Since the wakeup interval is a primary parameter for determining the sleeping schedule, how to tune the wakeup interval is crucial for the overall network performance. In this paper, we present an effective framework for tuning asynchronous wakeup intervals of IEEE 802.15.4 sensor networks from the energy consumption viewpoint. First, we derive an energy consumption model of each node as an explicit function of the wakeup interval, and empirically validate the derived model. Second, based on the proposed model, we formulate the problem of tuning the wakeup interval with the following two objectives: to minimize total energy consumption and to maximize network lifetime. We show that these two problems can be optimally solved by an iterative algorithm with global information by virtue of the convexity of the problem structure. Finally, as practical solutions, we further propose heuristic optimization algorithms that only exploit local information. In order to develop heuristic algorithms, we propose two broadcasting schemes, which are entitled as maximum wakeup interval broadcasting and efficient local maximum broadcasting. These broadcasting algorithms enable nodes in the network to have heterogeneous wakeup intervals. 相似文献
198.
Some Effective Techniques for Naive Bayes Text Classification 总被引:3,自引:0,他引:3
Sang-Bum Kim Kyoung-Soo Han Hae-Chang Rim Sung Hyon Myaeng 《Knowledge and Data Engineering, IEEE Transactions on》2006,18(11):1457-1466
While naive Bayes is quite effective in various data mining tasks, it shows a disappointing result in the automatic text classification problem. Based on the observation of naive Bayes for the natural language text, we found a serious problem in the parameter estimation process, which causes poor results in text classification domain. In this paper, we propose two empirical heuristics: per-document text normalization and feature weighting method. While these are somewhat ad hoc methods, our proposed naive Bayes text classifier performs very well in the standard benchmark collections, competing with state-of-the-art text classifiers based on a highly complex learning method such as SVM 相似文献
199.
A variable-speed, constant-frequency (VSCF) power-conversion scheme with a permanent magnet DC (PMDC) brushless generator is proposed. The scheme is completely modeled for steady state by integrating the characteristic equations of the generator, the diode rectifier bridge and the inverter, and the harmonic characteristics for steady-state performance computation. Commutation overlap effects are also included. Key performance characteristics are experimentally verified with a laboratory prototype. The excellent correlation between the predicted and experimental results confirms the validity of the model. For the purpose of filter design, harmonics of the rectified generator voltages are analytically derived. A recommendation for overcoming the low power factor on the utility side at low speeds using the forced-commutated converters is given 相似文献
200.