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BFEL激光能量的计算

强激光与粒子束 2007年第5期19卷 737-740页

作者：戴建枰于莹中国科学院高能物理研究所北京100049

为进一步提高BFEL的小信号增益和确定激光能量等性能参数,用定态和非定态程序对BFEL激光的能量进行了计算和分析。计算结果表明:采取适当措施,将电子束的发射度由50πmm·mrad降低到30πmm·mrad,电子束宏脉冲宽度由5.0μs增加到6.5μs... 详细信息

为进一步提高BFEL的小信号增益和确定激光能量等性能参数,用定态和非定态程序对BFEL激光的能量进行了计算和分析。计算结果表明:采取适当措施,将电子束的发射度由50πmm·mrad降低到30πmm·mrad,电子束宏脉冲宽度由5.0μs增加到6.5μs,激光传输效率由40%增加到80%,BFEL的小信号增益将由16%增大到28%,输出激光的能量也将提高近一个量级。

关键词： BFEL 非定态程序增益激光能量

Dynamic radiological change of gliomas located in the paralimbic system and its clinical significance

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Chinese Medical Journal 2008年第8期121卷 713-715页

作者： CHEN Xu-zhu jianG Tao LI Shao-wu AI Lin dai jian-ping Department of Neuroimaging Beijing Tiantan Hospital Capital Medical University Beijing 100050 China Department of Neurosurgery Beijing Tiantan Hospital Capital Medical University Beijing 100050 China

Background The paralimbic system, which is composed of three parts, is an important functional unit. Gliomas located in the region remain a challenge for clinical treatment. However, the dynamic change of gliomas in the area has not been well documented. The purpose of this study was to identify the growth tendency of gliomas located in the paralimbic system and to obtain some suggestions for clinical treatment. Methods Eleven cases of gliomas located in the paralimbic system were recruited in the study. All of them were proven by pathology. Analysis of the serial radiological examinations in each patient was performed from the initial to the final examination, taking into consideration the following items： initial tumor location, final location and the growth tendency. Results In the initial and final examinations the ratios of insula involvement were 64% and 100%, respectively. On the other hand, the ratios of gliomas located in two or more parts of paralimbic system increased from 64% to 100% during the dynamic examination. Conclusions Even though the paralimbic system is composed of three independent anatomical parts, gliomas tend to involve all three parts, especially the insula. Therapeutic plans should aim at the whole region of the system, even during the early stages of gliomas.

关键词： paralimbic system glioma white matter fiber tracts

Disease distribution and medical resources during the Beijing 2008 Olympic and Paralympic Games

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Chinese Medical Journal 2011年第7期124卷 1031-1036页

作者： LIANG Xue-ya LAN Ling CHEN Wei-na ZHANG Ai-ping LU Chao-ying LU Yan-wei dai jian-ping Department of Gastroenterology Beijing Jishuitan Hospital Beijing 100035 China Department of Endocrinology Beijing Jishuitan Hospital Beijing 100035 China Capital Institute of Physical Education Beijing 100191 China Games Services Department Beijing Organizing Committee for the Games of XXIX Olympiad Beijing Organizing Committee for Olympic Games for Short Beijing 100035 China Medical Services Division Beijing Organizing Committee for Olympic Games Beijing Municipal Health Bureau Beijing 100053 China Clinical Statistics and Epidemiology Research Office Beijing Research Institute of Tranmatology and Orthopaedics Beijing 100035 China Department of Radiology Tiantan Hospital Beijing 100050 China

Background Appropriate planning and staffing for medical services at large-scale athletic events is essential to provide for a safe and successful competition. There are few well-documented accounts describing the demand for such services. The present study provided the data from the Beijing 2008 Olympics and Paralympics, with a view to provide the guidance for planning future events.

关键词： Olympic Games ParaIympic Games disease distribution athletes

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爱因斯坦与康德

自然辩证法通讯 2006年第3期28卷 22-27页

作者：戴建平南京大学哲学系江苏南京210093

爱因斯坦在一生中多次阅读康德,他接受康德对概念和感觉经验的明确划分,并同样强调整理纷乱的感觉经验需要概念工具。但爱因斯坦不赞同康德的先验论,反对康德人为自然立法的观点,并否认几何学是康德所谓的“先天综合判断”。爱因斯坦对2... 详细信息

爱因斯坦在一生中多次阅读康德,他接受康德对概念和感觉经验的明确划分,并同样强调整理纷乱的感觉经验需要概念工具。但爱因斯坦不赞同康德的先验论,反对康德人为自然立法的观点,并否认几何学是康德所谓的“先天综合判断”。爱因斯坦对20世纪上半叶的一些新康德主义者也进行了批评。

关键词：爱因斯坦批评康德新康德主义

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利奥塔对现代科学的误读

华东师范大学学报（哲学社会科学版） 2009年第4期41卷 53-59页

作者：戴建平南京大学哲学系南京210093

利奥塔在其《后现代状态》一书中对现代科学产生了严重的误解。他根据维特根斯坦的语言游戏概念对现代科学进行了相对主义的理解,歪曲利用了科学哲学的一些结论,进而否认现代科学知识具有任何认识论上的优越地位。他夸大了科学知识所面... 详细信息

利奥塔在其《后现代状态》一书中对现代科学产生了严重的误解。他根据维特根斯坦的语言游戏概念对现代科学进行了相对主义的理解,歪曲利用了科学哲学的一些结论,进而否认现代科学知识具有任何认识论上的优越地位。他夸大了科学知识所面对的合法化危机,错误理解了元叙事和效率实证主义对科学合法化的意义。特别是,他援引的"量子力学"和非线性科学并不支持他的后现代立场,而他所说的追求差异、矛盾、不可理解性和异调逻辑的"后现代科学"并未出现。

关键词：语言游戏元叙事科学合法化后现代科学

Preoperative blood oxygen level-dependent functional magnetic resonance imaging in patients with gliomas involving the motor cortical areas

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Chinese Medical Journal 2008年第7期121卷 631-635页

作者： XIE jian CHEN Xu-zhu jianG Tao LI Shou-wei LI Zi-xiao ZHANG Zhong dai jian-ping WANG Zhong-cheng Department of Nearosurgery Beijing Tiantan Hospital Affiliated to Capital MedicalUniversity ~leijing 100050 China Department of Neuroimage Beijing Tiantan Hospital Affiliated to Capital MedicalUniversity Beijing 100050 China

Background Blood oxygen level-dependent （BOLD） functional magnetic resonance imaging （fMRI） plays an important role in identifying functional cortical areas of the brain, especially in patients with gliomas. This study aimed to assess the value of fMRI in presurgical planning and functional outcome of patients with gliomas in the motor cortical areas. Methods Twenty-six patients with gliomas in the motor cortex were recruited in the study. Before operation, fMRI was performed in each patient to obtain the mapping of bilateral hands area on the primary sensorimotor cortex. This examination was performed on a 3.0T scanner with a bilateral hands movement paradigm. During microsurgery under awake anesthesia, the motor area was identified using direct electrical stimulation and compared with preoperative mapping. Finally the tumor was resected as much as possible with the motor cortex preserved in each patient. Karnofsky performance status （KPS） was evaluated in all patients before and after operation. Results Twenty-three patients showed a successful fMRI mapping. Among them, 19 were calssified to be grade Ⅲ; 4, grade Ⅱ; 3, grade Ⅰ. The operation time was about 7 hours in the 23 patients, 8.5 hours in the other 3. The pre-and postoperative KPS score was 82.3±8.6 and 94.2±8.1, respectively. Conclusions Preoperative fMRI of the hand motor area shows a high consistency with intraoperative cortical electronic stimulation. Combined use of the two methods shows a maximum benefit in surgical treatment.

关键词： magnetic resonance imaging, functional motor cortex electrical stimulation glioma

Bunch length measurement using a traveling wave RF deflector

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Chinese Physics C 2010年第1期34卷 138-142页

作者： ZHANG Jing-Ru dai jian-ping GU Qiang PEI Guo Xi ZHAO Ming-Hua ZHONG Shao-Peng WANG Xing-Tao CHEN Yong-hong HOU Mi Institute of High Energy Physics CAS Graduate University of Chinese Academy of Sciences Shanghai Institute of Applied Physics CAS

RF deflectors can be used for bunch length measurement with high resolution. This paper describes a completed S-band traveling wave RF deflector and the bunch length measurement of the electron beam produced by the photocathode RF gun of the Shanghai DUV-FEL facility. This is the first time that such a transverse RF deflector has been developed and used to measure the bunch length of picosecond order in China. The deflector＇s VSWR is 1.06, the whole attenuation 0.5 dB, and the bandwidth 4.77 MHz for VSWR less than 1.1. With a laser pulse width of 8.5 ps, beam energy of 4.2 MeV, and bunch charge of 0.64 nC, the bunch lengths for different RF input power into the deflector were measured, and an averaged rms bunch length of 5.25 ps was obtained. A YAG crystal is used as a screen downstream of the deflector, with the calibrated value of 1 pix = 136 μm.

关键词： RF deflector bunch length RF gun HEM11 mode

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约瑟夫·劳斯的科学实践哲学方案

安徽大学学报（哲学社会科学版） 2009年第6期33卷 7-10页

作者：戴建平南京大学哲学系江苏南京210093

蔡仲认为,20世纪的科学哲学坚持表象主义的科学观,纠缠于知识和世界或表象之间的关系,陷入某种"认识论"的恐惧。20世纪90年代之后兴起的科学实践哲学转向科学实践的实际过程,转向实验室及其赖以生存的社会与文化语境,带来了新的科学图... 详细信息

蔡仲认为,20世纪的科学哲学坚持表象主义的科学观,纠缠于知识和世界或表象之间的关系,陷入某种"认识论"的恐惧。20世纪90年代之后兴起的科学实践哲学转向科学实践的实际过程,转向实验室及其赖以生存的社会与文化语境,带来了新的科学图景乃至划界标准,为我们重新理解马克思理论的科学性提出了新的任务。邢冬梅认为,作为实践和文化的科学强调科学的实际操作过程,而不是科学的表征性语言。对科学操作过程的把握,就是对科学实践过程中人类的力量和各种非人类的力量的相互作用和实际行为的描述,亦即对科学活动在具体的现时秩序中的情境的描述。知识应该被理解为对世界正在进行的参与的一个方面,而不是一个在原则上可以完成的任务。戴建平认为,劳斯的科学实践概念强调了科学理论、行动者和世界之间持续不断的相互作用以及对世界的构造,突出了科学实践的物质性和开放性。在此基础上,他提出了"科学的文化研究"方案,试图综合近20年来科学论领域内所有研究科学实践的不同进路。劳斯所强调的科学哲学的批判性具有重要的意义。

关键词：科学知识社会学实践哲学约瑟夫劳斯科学哲学实践研究哲学教授哲学传统

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BFEL电子束能量的调节

高能物理与核物理 2006年第Z1期30卷 93-95页

作者：戴建枰 V.Mytrochenko 中国科学院高能物理研究所北京100049 NSC KIPT

自由电子激光(FEL)相比于传统激光最大的优点之一便是能够较大范围、连续调节输出激光的波长．通常,较大范围调节FEL波长的方法是调节电子束的能量．通过对BFEL进行大量的模拟计算, 重点讨论了其在保持电子束优良性能的前提下,大范围调... 详细信息

自由电子激光(FEL)相比于传统激光最大的优点之一便是能够较大范围、连续调节输出激光的波长．通常,较大范围调节FEL波长的方法是调节电子束的能量．通过对BFEL进行大量的模拟计算, 重点讨论了其在保持电子束优良性能的前提下,大范围调节电子束能量的方法,包括:改变加速管的加速梯度、调整电子束的加速相位以及改变电子束的流强等．

关键词： BFEL 电子束能量模拟计算