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高能碰撞中喷注事件的产生率随碰撞质心能量变化的规律研究
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作者 刘明 刘峰 刘连寿 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 2000年第3期270-272,共3页
对“喷注的圆锥判定法”的两个判据之横能阈值作了分别对应于微喷注和大横动量喷注的两种不同选择 ,对这两种情况下不同碰撞质心能量的喷注事件产生率的变化规律进行了研究 ,并将这两种情况分析、比较 ,讨论它们的可能的应用 .
关键词 高能碰撞 喷注事件 圆锥判定法 质心能量 产生率
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多重数和质心能量的关系 被引量:1
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作者 陈奋策 《烟台师范学院学报(自然科学版)》 1989年第1期42-49,共8页
本文以夸克-胶子等离子体模型为基础,在平衡态近似下用温度场论描述中心在快度小的区域产生粒子的源Ⅰ,辅以多边缘机制处理中心在快度较大区域的产生粒子的源Ⅱ,得到高能PP(P)碰撞非单衍过程产生的多重数和质心系能量的关系式。关系式... 本文以夸克-胶子等离子体模型为基础,在平衡态近似下用温度场论描述中心在快度小的区域产生粒子的源Ⅰ,辅以多边缘机制处理中心在快度较大区域的产生粒子的源Ⅱ,得到高能PP(P)碰撞非单衍过程产生的多重数和质心系能量的关系式。关系式和实验数据符合得很好。 展开更多
关键词 多重数 夸克-胶子等离子体 温度场论 强相互作用 高能强子碰撞 质心能量
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雷达/红外双模导引头抗红外诱饵干扰 被引量:9
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作者 曾宪伟 方洋旺 +2 位作者 王洪强 王锋 卢虎 《红外与激光工程》 EI CSCD 北大核心 2009年第6期1054-1059,共6页
红外诱饵干扰弹是常见的影响导弹命中精度的干扰手段之一,对雷达/红外双模导引头抗红外诱饵干扰弹进行研究具有重要的理论价值和工程应用价值。在对红外诱饵干扰原理研究的基础上对系统进行建模,通过计算能量质心位置建立了雷达/红外双... 红外诱饵干扰弹是常见的影响导弹命中精度的干扰手段之一,对雷达/红外双模导引头抗红外诱饵干扰弹进行研究具有重要的理论价值和工程应用价值。在对红外诱饵干扰原理研究的基础上对系统进行建模,通过计算能量质心位置建立了雷达/红外双模状态方程和量测方程;设计了一种抗干扰方法,提出一种通过辐射能量和角度偏差方程进行红外诱饵干扰检测的方法。仿真分析表明:雷达/红外双模导引头使用该抗干扰方法能够以超过90%概率检测红外诱饵干扰,跟踪精度高,脱靶量小,验证了方法的可行性。 展开更多
关键词 红外诱饵干扰弹 雷达/红外双模 能量质心 红外诱饵干扰检测
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双光子碰撞产生电子对的单圈弱电辐射修正
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作者 曾代敏 方祯云 +1 位作者 胡炳全 李志峰 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第8期92-95,共4页
通过在标准模型下对双光子碰撞产生正负电子对的弱电辐射修正———包括虚修正和软光子修正的计算,得到了双光子碰撞产生电子对过程在单圈修正下的散射截面.在GLC对撞机设计的亮度监测范围内,讨论了树图和单圈弱电修正下散射截面随质心... 通过在标准模型下对双光子碰撞产生正负电子对的弱电辐射修正———包括虚修正和软光子修正的计算,得到了双光子碰撞产生电子对过程在单圈修正下的散射截面.在GLC对撞机设计的亮度监测范围内,讨论了树图和单圈弱电修正下散射截面随质心能量的变化关系及其微分截面随出射电子方位角的变化曲线. 展开更多
关键词 弱电辐射修正 散射截面 质心能量 微分截面
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标准模型下双光子碰撞产生τ^+τ^-的一圈弱电辐射修正
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作者 蒋敏 胡炳全 方祯云 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第9期116-119,共4页
通过在标准模型下对双光子碰撞产生τ+τ-的弱电辐射修正———包括虚修正和软光子修正的计算,得到了单圈修正下γγ→τ+τ-过程的散射截面,并讨论了树图和单圈弱电修正下散射截面随质心能量s的变化关系的比较.本项研究对实验测量单个H... 通过在标准模型下对双光子碰撞产生τ+τ-的弱电辐射修正———包括虚修正和软光子修正的计算,得到了单圈修正下γγ→τ+τ-过程的散射截面,并讨论了树图和单圈弱电修正下散射截面随质心能量s的变化关系的比较.本项研究对实验测量单个H iggs粒子产生的背景的分析非常重要. 展开更多
关键词 弱电辐射修正 散射截面 质心能量
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标准模型下γγ→μ ^+μ^-过程的弱电辐射修正
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作者 孙红娟 胡炳全 方祯云 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第10期104-107,共4页
通过在标准模型下对双光子碰撞产生正负μ子对的弱电辐射修正———包括虚修正和软光子修正的计算,得到了单圈修正下γγ→μ+μ-过程的散射截面.并在较大范围内给出了树图和单圈弱电修正下散射截面随质心能量s的变化关系.此结果对双光... 通过在标准模型下对双光子碰撞产生正负μ子对的弱电辐射修正———包括虚修正和软光子修正的计算,得到了单圈修正下γγ→μ+μ-过程的散射截面.并在较大范围内给出了树图和单圈弱电修正下散射截面随质心能量s的变化关系.此结果对双光子碰撞产生H iggs粒子的测量背景扣除具有重要意义. 展开更多
关键词 弱电辐射修正 散射截面 质心能量 微分截面
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正负电子湮灭中粒子的快度分布
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作者 段麦英 郭志俊 《山西师范大学学报(自然科学版)》 2001年第4期21-24,共4页
用修正了的热化柱模型分析了高能碰撞中粒子的快度分布 ,计算结果与质心能量 s=1 4,2 2 ,2 9,和 3 4 Ge V的 e+ e- 湮灭的实验数据符合 .
关键词 正负电子湮灭 快度分布 热化柱模型 高能粒子碰撞 质心能量 赝快度分布
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一代Technicolor模型对过程e^+e^-→tc的贡献
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作者 魏书坤 王增宝 +1 位作者 黄斌 孟春萍 《河南师范大学学报(自然科学版)》 CAS CSCD 1997年第1期48-50,共3页
在LEPI的能量(S=200GeV)下,我们计算了一代Technicolor(TC)模型对过程e+e-→tc的贡献.计算结果表明,一代TC模型对e+e-→tc的贡献很小。
关键词 质心能量 超对称模型 T模型 夸克 碰撞
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Systematic study of dynamical dipole mode via the isospin-dependent Boltzmann-Uehling-Uhlenbeck model 被引量:1
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作者 叶绍强 蔡翔舟 +2 位作者 方德清 马余刚 沈文庆 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第3期55-59,共5页
Dynamical dipole mode in heavy-ion collisions has been studied by using an isospin-dependent BoltzmannUehling-Uhlenbeck(IBUU) model. We investigate the dependence of centroid energy and strength of the γspectrum on b... Dynamical dipole mode in heavy-ion collisions has been studied by using an isospin-dependent BoltzmannUehling-Uhlenbeck(IBUU) model. We investigate the dependence of centroid energy and strength of the γspectrum on beam energy, N/Z ratio and mass asymmetry. The calculated yield and angular distribution of theγ-ray produced by dynamical dipole emission are consistent with the experimental data. The results show that the detailed study of dynamical dipole radiation can provide information on the isospin evolution of chargeasymmetric heavy-ion collisions around the normal nuclear density. 展开更多
关键词 同位旋相关 碰撞动力学 偶极辐射 模型系统 重离子碰撞 玻尔 质心能量 不对称性
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Fitness and health benefits of team handball training for young untrained women--A cross-disciplinary RCT on physiological adaptations and motivational aspects 被引量:8
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作者 Therese Hornstrup Johan M.Wikman +7 位作者 Bjorn Fristrup Susana Povoas Eva W.Helge Signe H.Nielsen Jorn W.Helge Jesper L.Andersen Lars Nybo Peter Krustrup 《Journal of Sport and Health Science》 SCIE 2018年第2期139-148,共10页
Purpose: The present study evaluated the effects of regular participation in small-sided team handball training on body composition, osteogenic response, physical performance, and cardiovascular risk factors, as well ... Purpose: The present study evaluated the effects of regular participation in small-sided team handball training on body composition, osteogenic response, physical performance, and cardiovascular risk factors, as well as well-being and motivation, in young untrained women.Methods: Twenty-eight untrained 20- to 30-year-old women were randomized to a handball training group(HG; n = 14, height 170 ± 5 cm, weight 73 ± 11 kg, VO_(2peak) 37.7 ± 4.1 mL/min/kg) that trained 1.7 ± 0.3 times per week over 12 weeks(70 min 4 v 4 handball sessions) or an inactive control group(CG; n = 14, 169 ± 5 cm, 71 ± 12 kg, 38.1 ± 3.7 mL/min/kg). Physiological and psychological and motivational training adaptations were assessed pre-and post-intervention by dual-energy X-ray Absorptiometry(DXA) scans, blood sampling, physical tests, and questionnaires.Results: The average heart rate(HR) over all training sessions was equal to 85% ± 6% HR_(max). Between-group intervention effects were observed in favor of HG for muscle mass(2.1%, p = 0.024), proximal femur bone mineral density(0.8%, p = 0.041), Yo-Yo IE1 intermittent endurance test level 1(IE1) performance(35%, p < 0.001), and incremental treadmill test performance(11.5%, p = 0.003), but not total fat mass(p = 0.176),mean arterial blood pressure(p = 0.328), resting HR(p = 0.219), or blood lipids(p = 0.298—0.854). In CG, no changes were observed in any of the measured physiological variables after the training period. Compared to CG, HG had an increase in intrinsic motivation(p < 0.001) and in the well-being subscale "energy"(p = 0.010).Conclusion: Participation in regular recreational team handball training organized as small-sided games has marked beneficial effects on physical performance, musculoskeletal fitness, well-being, and motivation in untrained young women. 展开更多
关键词 Bone mineral density (BMD) Intensity INTERMITTENT Motivation Muscle mass Physical performance Recreational handball WELL-BEING
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ESTIMATION OF DOPPLER CENTROID FREQUENCY IN SPACEBORNE SCANSAR 被引量:3
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作者 Zou Xiufang Zhang Qunying 《Journal of Electronics(China)》 2008年第6期822-826,共5页
Doppler centroid frequency is an essential parameter in the imaging processing of the Scanning mode Synthetic Aperture Radar (ScanSAR). Inaccurate Doppler centroid frequency will result in ghost images in imaging resu... Doppler centroid frequency is an essential parameter in the imaging processing of the Scanning mode Synthetic Aperture Radar (ScanSAR). Inaccurate Doppler centroid frequency will result in ghost images in imaging result. In this letter, the principle and algorithms of Doppler centroid frequency estimation are introduced. Then the echo data of ScanSAR system is analyzed. Based on the algorithms of energy balancing and correlation Doppler estimator in the estimation of Doppler centroid frequency in strip mode SAR, an improved method for Doppler centroid frequency estimation in ScanSAR is proposed. The method has improved the accuracy of Doppler centroid frequency estimation in ScanSAR by zero padding between burst data. Finally, the proposed method is validated with the processing of ENVIronment SATellite Advanced Synthetic Aperture Radar (ENVISAT ASAR) wide swath raw data. 展开更多
关键词 Spaceborne the Scanning mode Synthetic Aperture Radar (ScanSAR) Doppler centroid frequency Energy balancing Correlation Doppler estimator
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Development and validation of a rapid psychosocial well-being screening tool in patients with metastatic breast cancer
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作者 Bhumipat Thanasansomboon Songphan Choemprayong +3 位作者 Napa Parinyanitikul Uthai Tanlamai Manika Wisessathorn Yupin Patarapongsant 《International Journal of Nursing Sciences》 CSCD 2022年第3期303-312,I0002,共11页
Objective The aim of this study was to develop and validate a rapid psychosocial well-being screening tool for metastatic breast cancer patients(MBC-PsySoc-Well-being).Methods Applying a mixed method approach,the stud... Objective The aim of this study was to develop and validate a rapid psychosocial well-being screening tool for metastatic breast cancer patients(MBC-PsySoc-Well-being).Methods Applying a mixed method approach,the study was conducted in two phases.Phase 1,a focus group method was employed for item development,and three focus group sessions were conducted,with patients,caregivers,and medical professionals,respectively.Phase 2,validity and reliability testing were performed.Five experts reviewed items for content validity.Construct validity,criterion-related validity,internal consistency,and test-retest reliability were conducted among a sample of 53 patients with metastatic breast cancer.Results Six themes were qualitatively analyzed based on focus group participants’responses.Eight items were then developed based on these themes.The index of Item-Objective Congruence scored by the experts ranged from 0.6 to 1.0.An exploratory factor analysis yielded three factors:Being curious and active in information seeking,Enthusiasm to return to a normal life,and Adjusting to positive lifestyle.The total scores of MBC-PsySoc-Well-being and the European Organization for Research and Treatment of Cancer’s Quality of Life Core Questionnaire(EORTC QLQ-C30)were moderately correlated(r=0.404,P=0.003).Cronbach’sαcoefficient of the overall scale was 0.686.Pearson correlation coefficients of items between two tests within 14-day ranged from 0.410 to 0.673.Conclusion This study represents an initiative to develop a rapid psychosocial well-being screening tool for patients with metastatic breast cancer.The results from validity and reliability testing indicate that the scale is moderately suitable for application to patients with metastatic breast cancer.However,a larger scale study should be further administered to confirm the validity and reliability of the measurement. 展开更多
关键词 Breast neoplasms Focus groups Information seeking behavior MEASUREMENT Psychosocial functioning Quality of life
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Analysis on the Relationship among Memorizing Ability, Note-taking, and Psychological Factors in Interpretation Teaching
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作者 Yufang RUAN 《International Journal of Technology Management》 2013年第6期68-70,共3页
Since China's reform and accession to the world trade organization (WTO), the international labor division, cooperation, and communication of production have been a direction of the global productivity development.... Since China's reform and accession to the world trade organization (WTO), the international labor division, cooperation, and communication of production have been a direction of the global productivity development. The expansion of the world trade organization and the growth of multinational corporations have promoted China's market economy to head for internationalization; the exchanges of all countries' science and technology, culture, and education have become increasingly frequent and beyond the borders very early, so opening-up has become a world trend. China is playing an important role in this historical process. In this situation, the importance of language translation is increasing day by day, and an unprecedented prosperous situation has especially appeared to the interpretation. In order to accord with this new historical situation, many colleges and universities have set up language translation program and have offered interpretation course. To promote the economic development of China and train more senior interpreters, the studies of interpretation teaching and the improvement of interpretation teaching quality have been particularly important. In this paper, the relationship among memory, note-taking, and psychological factors are analyzed. 展开更多
关键词 The Current Situation of Interpretation Teaching MEMORY Note-taking Psychological Factors and the Teaching Effect
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利用HIJING产生器对RHIC能区质子反质子产额比的研究(英文) 被引量:1
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作者 王琴 李治明 刘峰 《高能物理与核物理》 EI CSCD 北大核心 2002年第1期64-68,共5页
利用HIJING 2 .0MonteCarlo事件产生器产生了RHIC能区 (质心系能量1 3 0GeV和 2 0 0GeV)的Au +Au最小无偏碰撞事件 .对产生的事件样本进行分析表明 :碰撞参数与事件的多重数有近似线性依赖关系 ,两者都可用来表征碰撞的对心度 ;质子反... 利用HIJING 2 .0MonteCarlo事件产生器产生了RHIC能区 (质心系能量1 3 0GeV和 2 0 0GeV)的Au +Au最小无偏碰撞事件 .对产生的事件样本进行分析表明 :碰撞参数与事件的多重数有近似线性依赖关系 ,两者都可用来表征碰撞的对心度 ;质子反质子产额比不明显依赖于碰撞对心度、横动量、快度和事件平面 . 展开更多
关键词 QCD HIJING 质子反质子产额比 对心度 产生器 RHIC能区 碰撞参数 事件多重数 量子色动力学 MonteCarto事件 质心能量
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γγ→γZ过程高能总截面的数值计算
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作者 东方晓 勾亮 周咸建 《高能物理与核物理》 CSCD 北大核心 2001年第4期283-288,共6页
给出了γγ→γZ过程 ,质心系总能量在 91 2— 2 0 0 0GeV的总截面 .结果表明在总能量大于 1 40GeV时 ,W玻色子图的贡献比起费米子图的贡献要大 ,当总能量在 750GeV左右 ,截面达到极大值 2 2 0fb(|cosθ| <cos1 5°) ,这时W玻... 给出了γγ→γZ过程 ,质心系总能量在 91 2— 2 0 0 0GeV的总截面 .结果表明在总能量大于 1 40GeV时 ,W玻色子图的贡献比起费米子图的贡献要大 ,当总能量在 750GeV左右 ,截面达到极大值 2 2 0fb(|cosθ| <cos1 5°) ,这时W玻色子图的贡献是主要的 (比费米子图的贡献大 3— 4个量级 ) .这比γγ→γγ相应极大总截面大一个量级 .若今后γγ对撞机的亮度达 1 0 33cm- 2 ·sec- 1,每年在总能量 750GeV处可观察到 60 0 0多个γγ→γZ事例 ,用它可以进一步验证标准模型 。 展开更多
关键词 手征振幅 散射截面 极化矢量 γγ→γZ过程 圈图 量子电动力学 质心系总能量
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Sensitivity study of searching for τ^-→γμ^- at HIEPA
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作者 Yu-Bo Li Cheng-Ping Shen Chang-Zheng Yuan 《Science Bulletin》 SCIE EI CAS CSCD 2016年第4期307-312,共6页
The charged lepton flavor violation process is a clean and sensitive probe of new physics beyond the Standard Model. A sensitivity study is performed to the process τ^-→γμ^- based on a 3 fb^(-1) inclusive Monte Ca... The charged lepton flavor violation process is a clean and sensitive probe of new physics beyond the Standard Model. A sensitivity study is performed to the process τ^-→γμ^- based on a 3 fb^(-1) inclusive Monte Carlo sample of e^+e^- collisions at a center-of-mass energy of4.26 or 4.6 Ge V, in the framework of the BESIII software system. The 90 % confidence level upper limits on B(τ^-→γμ^-) are estimated assuming no signal is produced. We also obtain the sensitivity on B(τ^-→γμ^-) as a function of the integrated luminosity, to serve as a reference for the HIEPA being proposed in China. It is found that 6.34 ab^(-1) are needed to reach the current best upper limit of 4:4 10^(-8) and about 2510 ab^(-1) are needed to reach a sensitivity of 10^(-9) if the detector design is similar to that of BESIII. 展开更多
关键词 Charged lepton flavor violation Branching fraction New physics
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