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91.
考虑碳排放税,建立双寡头制造商分别实施废品回收和绿色低碳广告投入策略的动态博弈模型。通过系统稳定域,分岔图,功率谱等分析了博弈模型纳什均衡解处的稳定性及参数对系统稳定域的影响,同时对系统的复杂性特征进行了研究。结果表明,消费者回收价格敏感性增加会使整个系统稳定域缩小,而绿色低碳广告投入水平增加只会使实施该策略的企业自身稳定域扩大;当制造商价格调整速度过快时,系统会进入混沌状态;混沌状态下,对比实施广告策略的制造商,实施废品回收策略的制造商价格调整行为对市场造成的震荡更大。最后使用反馈控制策略对系统混沌状态进行了有效的控制,研究结果对制造商低碳策略选择及价格决策有着较好的借鉴意义。  相似文献   
92.
Z4-Kerdock Codes, Orthogonal Spreads, and Extremal Euclidean Line-Sets   总被引:3,自引:0,他引:3  
When m is odd, spreads in an orthogonal vector space of type+(2m + 2,2) are related to binary Kerdock codes and extremalline-sets in 2m + 1 with prescribed angles. Spreads in a 2m-dimensionalbinary symplectic vector space are related to Kerdock codesover Z4 and extremal line-sets in with prescribed angles. These connections involve binary, realand complex geometry associated with extraspecial 2-groups.A geometric map from symplectic to orthogonal spreads is shownto induce the Gray map from a corresponding Z4-Kerdock codeto its binary image. These geometric considerations lead tothe construction, for any odd composite m, of large numbersof Z4-Kerdock codes. They also produce new Z4-linear Kerdockand Preparata codes. 1991 Mathematics Subject Classification:primary 94B60; secondary 51M15, 20C99.  相似文献   
93.
Inclusive ? meson production has been measured for 100 GeV/c and 200 GeV/c incident π?, \(\bar p\) andK ?, and for 120 GeV/c and 200 GeV/c incident π+,p andK +, using a Be target. A total of 630,000 ? mesons has been recorded in the kinematic range 0<x F <0.4. Presented are the differential cross sectionsdσ/dx F anddσ/dp T 2. The longitudinal momentum distributions show that the strange valence quarks of the incidentK mesons play an important role in ? meson production, even at smallx F . The decay angular distribution of the ? meson is evaluated in the Gottfried-Jackson frame and is expressed in the elements of the density matrix. There is a small but significant cos2 θ GJ dependence for smallp T , which decreases for increasingp T .  相似文献   
94.
The parton fusion model is used to describe the longitudinal differential cross section (dσ/dx F ) of hadronic ? production. Thedσ/dx F for ? production in π± p, \(\mathop p\limits^{( - )} p\) andK ± p interactions is evaluated in the model by using structure functions for the constituents of the interacting particles. A comparison between the model and high statistics data in the Feynmanx range 0.0<x F (?)<0.4 allows the determination of the strange valence quark distribution inK mesons and the strange sea quark distribution in π mesons, which appears to be harder than the light sea quark distribution. The comparison also shows that a significant part of inclusive ? production is due to the OZI allowed fusion of strange quarks, while the OZI inhibited fusion diagrams are strongly suppressed.  相似文献   
95.
The NA 32 experiment at the CERN SPS has collected 38 million hadronic interactions with incident 200 GeV/c π?,K ? andp beam. Using a segmented silicon active target and a telescope of high resolution silicon microstrip counters we have selected fully reconstructedD 0K ?π+,D 0K ?π+π+π?,D +K ?π+π+,D s + K ? K +π+π+ and charge conjugate decays. The integrated cross-sections forD o,D + D *+ andD s + meson production and the dependence of the cross-section on longitudinal and transverse momentum of theD are presented.  相似文献   
96.
The reactionpBe→Λ(1,520)X has been measured at 100 GeV incident momentum in the kinematic range 0.15<x<0.35 \((x = 2p_\parallel ^{c.m} /\sqrt s )\) andP T <1 GeV. The invariant cross section is compatible with that measured forpp interactions at the CERN-ISR. The differential cross sectiondσ/dp T 2 is fitted to an exponentiale p T 2 with α=2.7 GeV?2.  相似文献   
97.
98.
Situ C  Wylie AR  Douglas A  Elliott CT 《Talanta》2008,76(4):832-836
Surface plasmon resonance (SPR) based biosensor technology has been widely used in life science research for many applications. While the advantages of speed, ruggedness, versatility, sensitivity and reproducibility are often quoted, many researchers have experienced severe problem of non-specific binding (NSB) to chip surfaces when performing analysis of biological samples such as bovine serum. Using the direct measurement of the bovine protein leptin, present in bovine serum samples as a model, a unique buffering system has been developed and optimised which was able to significantly reduce the non-specific interactions of bovine serum components with the carboxymethyl dextran chip (CM5) surface on a Biacore SPR system. The developed NSB buffering system comprised of HBS-EP buffer, containing 0.5 M NaCl, 0.005% CM-dextran, pH 9.0. An average NSB reduction (n = 20) of 85.9% and 87.3% was found on an unmodified CM5 surface and a CM5 with bovine leptin immobilised on the chip surface, respectively. A reduction in NSB of up to 94% was observed on both surfaces. The concentration of the constitutive components and pH of the buffer were crucial in achieving this outcome.  相似文献   
99.
OBJECTIVE: The present study reports on the important issue of how family communication and support regarding breast cancer risk affects interest in genetic testing and mental health. METHODS: Participants (n = 221) were women aged 18-74 who had at least one relative of Ashkenazi Jewish descent, no personal history of breast or ovarian cancer, and lived within 60 miles of Seattle, Wash. RESULTS: Communication about breast cancer risk was reported with very low frequency across all types of relatives. Women talked with their mothers and sisters more often than their fathers, brothers, or children. The only significant predictor of interest in genetic testing was the individual level variable of seeking social support. CONCLUSION: Social support needs might be a part of the genetic testing process.  相似文献   
100.
Journal of Radioanalytical and Nuclear Chemistry - A 30&nbsp;year-old PuF4 sample consisting of brown powder (PuF4-b) and pink granules (PuF4-p) was analyzed. X-ray diffraction shows the bulk...  相似文献   
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