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涡发生器间距对翼型气动性能影响的实验研究

太阳能学报 2018年第9期39卷 2410-2417页

作者：胡昊李新凯王晓东康顺华北水利水电大学电力学院郑州450045 中国科学院工程热物理研究所北京100190 华北电力大学能源动力与机械工程学院北京102206

以DU93-W-2.0风力机号用翼型为研究对象，采用风洞实验方法研究4组涡发生器（VGs）例距（S=5.、7h、13H、19H，H为VGs高度）对翼型气动性能的影响规律。风洞实验结果发现：在清净翼型失速攻角（8°）之前，涡发生器对翼型的升力系数影... 详细信息

以DU93-W-2.0风力机号用翼型为研究对象，采用风洞实验方法研究4组涡发生器（VGs）例距（S=5.、7h、13H、19H，H为VGs高度）对翼型气动性能的影响规律。风洞实验结果发现：在清净翼型失速攻角（8°）之前，涡发生器对翼型的升力系数影响较小。而对于阻力系数及升阻比，当间距S=5.、7H时会使翼型的阻力系数增加，其中S=5.时阻力最多增加2.％，升阻比降低19％。间距S=13H、19H时使翼型阻力系数降低，其中S=13H时阻力最多降低70％，升阻比最多增加160％；在翼型失速攻角（8°）之后，涡发生器均能增加翼型升力、降低阻力、增加升阻比，其中S=5.时翼型升力系数最多增加48％，增加失速攻角近10°，且在失速攻角之后，S=5.时翼型升阻比增加最多。故加装涡发生器不一定在全攻角范同内均增加翼型升阻比，但会增加翼型最佳升阻比的攻角范围。所以，涡发生器存在最佳间距，若从最大升力系数来判断，当间距S=5.时效果最佳。若从最大升阻比来看，当间距S=13H时效果更佳。

关键词：涡发生器翼型气动性能风洞实验

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我国胆石病十年来的变迁

中华外科杂志 1995年第11期33卷 652-658页

作者： Zhu Xueguang Zhang Shengduo HuangZhiqiang et al. People′s Hospital,beijing Medical U-niversity,beijing100044. People's Hospital Beijing Medical University.

作者报道了由全国胆道外科学组组织的来自７个省市、３３所医院３９１１例胆结石手术病例的第二次全国临床调查资料并与十年前首次调查的结果（中华外科杂志１９８７，２５：３２１～３２９）比较。调查证实：胆石病仍是我国普外临床的... 详细信息

作者报道了由全国胆道外科学组组织的来自７个省市、３３所医院３９１１例胆结石手术病例的第二次全国临床调查资料并与十年前首次调查的结果（中华外科杂志１９８７，２５：３２１～３２９）比较。调查证实：胆石病仍是我国普外临床的多发病，约占同时期住院患者的１１．５％；多见于５０岁以上的女性；女：男约２．５７：１。约８０％的单一部位结石分布于胆囊，以胆固醇类结石为主；而以胆色素类为主的胆管结石仅占１０％。与十年前相比，胆囊：胆管结石从１．５：１上升至７．３６：１；胆固醇：胆色素结石从１．４：１升至３．４：１。调查还发现：上述关于结石类型及结石部位上的变化与近十年来胆道蛔虫及胆道感染率的显著下降及饮食结构的变化有关。

关键词：胆结石胆囊胆管胆固醇胆色素流行病学

CRYSTAL STRUCTURE OF 2.METHYL-4-（ρ-）METHYLPHENYL-2.3-DIHYDRO- BENZO-（l,5.-DIAZEPINE(C17H18N2.

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结构化学 1985年第3期 195-198页

作者： Li Qi Jin Sheng Zhou Gongdu Department of Chemistry, beijing Normal University Department of Chemistry, beijing University Institute of Physical Chemistry, beijing University

INTRODUCTION. The study of the title compound is a part of our systematic investigations on the 2.4-substituted derivatives of benzo- seven-membered heterocyclic system, in recent years. The comparison of conformation... 详细信息

关键词： METHYLPHENYL-2.3-DIHYDRO l,5 DIAZEPINE N2 BENZO CRYSTAL STRUCTURE OF 2.METHYL-4

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凡士林纱布含脂量与灭菌效果研究

护理研究 2004年第10期18卷 1764-1765页

作者：李力黄秀娥刘颖中国中医研究院望京医院 100102

[1]指出:压力蒸汽灭菌不能用于凡士林等油类和粉剂的灭菌,而适宜于干热灭菌.凡士林与凡士林纱布不是一个概念,凡士林属于油脂类,而凡士林纱布为带有孔隙的油脂类织物;凡士林等油剂的灭菌条件是要求厚度不超过0.635.cm,而凡士林纱布的灭... 详细信息

[1]指出:压力蒸汽灭菌不能用于凡士林等油类和粉剂的灭菌,而适宜于干热灭菌.凡士林与凡士林纱布不是一个概念,凡士林属于油脂类,而凡士林纱布为带有孔隙的油脂类织物;凡士林等油剂的灭菌条件是要求厚度不超过0.635.cm,而凡士林纱布的灭菌条件要求厚度不超过1.3 cm,重量不超过112.[1,2..根据凡士林纱布是带有孔隙的油脂类织物的特点,本研究首先将凡士林与纱布的重量分别进行了5.1、4:1、3:1、2.1、1:1的试验筛选.筛选结果显示:≤2.1的凡士林纱布较干、较硬、柔软性差;＞3:1的凡士林纱布油脂饱满,纱网孔隙被油脂腻满的程度随重量比的递增而增加;而3:1的凡士林纱布油润,纱网孔隙可见,质地柔软适中,有利于外科的填塞、覆盖、引流等.本研究以3:1重量比的凡士林纱布为样本材料,采用脉动真空压力蒸汽灭菌法反复试验观察,并验证了灭菌效果是达标的,灭菌方法是易行的,有利于基层医疗单位应用参考.

关键词：凡士林纱布含脂量灭菌效果研究检测

A FAST SPHERE DECODING ALGORITHM FULLY EXPLOITING THE ORTHOGONALITY OF STBC

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A FAST SPHERE DECODING ALGORITHM FULLY EXPLOITING THE ORTHOG...

肺部肿瘤基于最大密度投影图像和四维CT勾画的内靶区差异性分析

2.09 IEEE Youth Conference on Information,Computing and Telecommunication(YC-ICT2.09)

作者： WANG Li, JIANG Hua, SHAO Lan, LIN Yicheng, WANG Wenbo Wireless Signal Processing and Network Lab Key Laboratory of Universal Wireless Communication, Ministry of Education beijing University of Posts and Telecommunications, beijing{2.

In this paper, we propose a fast sphere decoding (SD) algo- rithms for the STBCs whose symbols can be decoupled into several orthogonal groups. The orthogonality of the front levels and the last levels are both utilized, while all the former improved SD algorithms only consider the orthogonality of the last levels. By the proposed algorithm, weights calculation of the front and the last levels are respectively performed independently, thus the computational complexity is significantly reduced. As for the bit error ratio performance, it is not influenced at all. The simulation results show the advantage of our proposed fast SD in complexity economization over a former improved SD algorithm.

关键词： STBC, sphere decoding

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中国医学物理学杂志 2018年第2期35卷 135-140页

作者：宋孟孟王运来黄祥鞠忠建戴相昆吴青南武汉大学物理科学与技术学院湖北武汉430072 中国人民解放军总医院放疗科北京100853

目的:基于不同部位的肺部肿瘤患者四维CT(4DCT)图像,比较最大密度投影图像(MIP)与4DCT图像勾画肺部肿瘤的体积和形状差异。方法:选择肿瘤分别位于肺部中央、靠近胸壁胸椎、紧邻血管、肝脏与心脏或者淋巴结转移并伴随肺不张患者共12.,... 详细信息

目的:基于不同部位的肺部肿瘤患者四维CT(4DCT)图像,比较最大密度投影图像(MIP)与4DCT图像勾画肺部肿瘤的体积和形状差异。方法:选择肿瘤分别位于肺部中央、靠近胸壁胸椎、紧邻血管、肝脏与心脏或者淋巴结转移并伴随肺不张患者共12.,在平静呼吸状态扫描得到4DCT图像。MIM软件对4DCT图像进行处理得到MIP图像和平均密度投影图像(AIP)。由同一位医生在4DCT的10个呼吸时相图像依次勾画靶区GTV_(0%)、GTV_(10%)、……GTV_(90%),再合成内靶区(ITV_(4D));同时分别在MIP图像和AIP图像勾画ITV_(MIP)和GTV_(AIP)。读取ITV_(MIP)与ITV_(4D)的体积及质心坐标,计算ITV_(MIP)与ITV_(4D)的相似性系数(Dice)以及豪斯多夫距离(Hausdorff)最大值。结果:靶区在肺中央或者靠近胸壁的7位患者,靶区体积比(V_(MIP)/V_(4D))与Dice系数均大于或约等于0.9,两者差值的平均值为0.06。Hausdorff距离最大值、质心位移平均值分别为3.2.0.65.mm。靶区紧邻血管、心脏瓣膜、肝脏或者伴随淋巴结转移及肺不张的5.患者,靶区体积比与Dice系数平均值分别为0.85.0.80,两者差值的平均值为0.13。Hausdorff距离最大值、质心位移平均值分别为9.4和3.0 mm。结论:对于边界清晰的肺部肿瘤,MIP图像和4DCT勾画的ITV相近。肿瘤周围有等密度组织时,MIP图像和4DCT图像勾画靶区差异较大。

关键词：肺部肿瘤内靶区 4DCT 最大密度投影图像相似性系数豪斯多夫距离最大值

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激光加工六轴机械手离线编程技术

中国激光 2003年第3期30卷 279-281页

作者：陈继民王颖娜左铁钏北京工业大学激光工程研究院北京100022

针对激光加工中六轴机械手在线示教编程效率低的问题 ,提出了进行离线编程的方法 ,并介绍了激光加工六轴机械手离线编程技术开发的实现步骤。通过离线编程能极大地提高激光加工效率 ,方便用户的使用。

关键词：机器人控制六轴机械手离线编程激光加工

Improving a method for evaluating alfalfa cultivar resistance to thrips

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Journal of Integrative Agriculture 2016年第3期15卷 600-607页

作者： TU Xiong-bing FAN Yao-li JI Ming-shan LIU Zhong-kuan XIE Nan LIU Zhen-yu ZHANG Ze-hua State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 P.R. China College of Plant Protection/Biopesticide Engineering Research Center of Liaoning Province Shenyang Agricultural University Shenyang 110161 P.R. China Institute of Agro-Resourse and Environment Hebei Academy of Agriculture and Forestry Sciences Shijiazhuang 050051 P R. China

The thrips quantity ratio（TQR） model is an important tool for evaluating crop resistance to thrips based on the correlation between thrips quantities and cultivars. Unfortunately, it is inaccurate, and the results appear significantly inconsistent when analysing the same cultivars in the same field study. To improve this model, we first studied the resistance of 2. alfalfa cultivars to thrips in Cangzhou, Hebei Province, north china. The results showed that the most suitable evaluation period was from May to June, as the thrips population was stable during this period. Second, we found that the natural enemy population was significantly positively correlated with the thrips population density（R=0.72.5. P〈0.0001）, which might influence resistance estimation. Hence, we introduced a parameter ‘α＇, corresponding to the natural enemy quantity ratio, to eliminate the effect of the natural enemy using ＂αTQR＂. Using the improved method, 2. cultivars were clustered into three classes： the resistant class, sensitive class, and median class. All numerical values were calculated for αTQR displayed as a Gaussian distribution. This information showed that all data should be divided into nine groups using a median value of 1±0.1 with an equal difference of 0.1. Based on the new standard cultivars, Gongnong 1, Alfaking, Cangzhou and Algonquin were classified as highly resistant cultivars; Zhongmu 3, Gongnong 2. Zhongmu 1 and Zhongmu 2.were classified in the resistant group; Queen was classified in the moderately resistant group; Derby, WL35.HQ, KRIMA, Apex, 5. HR, SARDI 5.and Farmers Treasure were classified in the median class; WL319HQ, WL343HQ and Sitel were classified as the low sensitive group; WL440 HQ and SARDI7 as the moderately sensitive group; WL168HQ and Sanditi as the sensitive group; and SARDI 10, WL363HQ, FD4, WL32. and SOCA as the highly sensitive group.

关键词： thrips quantity ratio(TQR) model alfalfa cultivar resistance thrips natural enemy

Studies　on　the　Mechanism　of　the　Direct　Synthesis　of　Styrene　form　Benzene　and　Ethylene

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Chemical Research in chinese Universities 1997年第3期13卷 244-248页

作者： ZHANG Qiang , JIN Ri-guang (College of Mater, Sci, and Tech, beijing Univ, of Them, beijing,10002.) YANG Jun (Dept. of Phys, Chem, Shenyang Pharmaceutical Univ., Shenyang,110015.

The adsorption behavior and description behavior of benzene , ethylene and ethylbenzene over HZSM-5.and Co/HZSM-5.catalysts were studied by means of TPSR (Temperature programmed surface reaction) technique. TPSR results of ben- zene and ethylene co-adsorption show that the maian products are styrene , ethylben- zene, toluene, propane, and butane. In a separate experiment of ethylbenzene ad- sorption, styrene . toluene and benzene are formed due to cracking and dehydro- genation. The mechanism of styrene formation was proposed , i. e. , the reaction was carried out via. the dehydrogenation of mediate species ethylbenzene according to the results of TPSR-MS , activity testing and thermodynamic analysis.

关键词： Direct synthesis TPSR-MS Styrene Benzene Ethylene