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Quantitative analysis of soil pores under natural vegetation successions on the Loess Plateau

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science china Earth sciences 2010年第4期53卷 617-625页

作者： ZHAO ShiWei1,ZHAO YongGang1,2 & WU JinShui3 1 State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest Agriculture & Forestry University,Yangling 712100,china 2 Graduate University of chinese Academy of sciences,Beijing 100049,china 3 Institute of Subtropical Agriculture,chinese Academy of sciences,Changsha 410125,china 1. State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Northwest Agriculture & Forestry University Yangling 712100 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 China

Soil pore is a key attribute of the soil structure that affects soil reservoir under natural vegetation recovery on the Loess *** study is to quantitatively analyze soil pore parameters,measured with Computed Tomography(ct) at 15-57 mm depths under five different vegetation succession stages using a concept of substituting "space" for "time" in the Ziwuling Forest Region of the Loess *** results showed that the soil pore parameters,such as pore number,porosity,circularity,and fractal dimension,increased significantly under the natural vegetation successions and varied with the pattern climax community stage>pioneering arbor community stage>scrub community stage>herbaceous community stage>abandoned farmland stage,indicating that natural vegetation recovery could remarkably improve soil pore *** the vegetation succession,this positive effect will be strengthened gradually,which means that the soil pore parameters may appear to be best at the climax community *** organic matter content increased linearly with the soil pore parameters(Pnges in soil pore characteristics in natural vegetation succession.

关键词： Computed Tomography Loess Plateau natural vegetation succession soil pore soil organic matter

Monitoring Glacier and Supra-glacier Lakes from space in Mt. Qomolangma Region of the Himalayas on the Tibetan Plateau in china

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Journal of Mountain science 2009年第3期6卷 211-220页

作者： YE Qinghua ZHOng Zhenwei KAng Shichang Alfred Stein WEI Qiufang LIU Jingshi key laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences (CAS) Beijing 100085 China State key laboratory of Remote Sensing science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China International Institutefor Geo-Information science and Earth observation (ITC) PO Box 67500 AA Enschede The Netherlands

Because of the large number and remoteness, satellite data, including microwave data and optical imagery, have commonly been used in alpine glaciers surveys. Using remote sensing and Geographical Information System （GIS） techniques, the paper presents the results of a multitemporal satellite glacier extent mapping and glacier changes by glacier sizes in the Mt. Qomolangma region at the northern slopes of the middle Himalayas over the Tibetan Plateau. Glaciers in this region have both retreated and advanced in the past 35 years, with retreat dominating. The glacier retreat area was 3.23 km2 （or o.75 km^2 yr^-1 during 1974 and 1976, 8.68 km^2 （or 0.36 km^2 yr^-1 during 1976 and 1992, 1.44 km^2 （or 0.12 km^2 yr^-1） during 1992-2ooo. 1.14 km^2 （or 0.22 km^2 yr^-1 during 2000-2003, and 0.52 km^2 （or 0.07 km^2 yr^-1 during 2003-2008, respectively. While supra-glacier lakes on the debris-terminus of the Rongbuk Glacier were enlarged dramatically at the same time, from 0.05 km^2 in 1974 increased to 0.71 km^2 in 2008, which was more than 13.times larger in the last 35 years. In addition, glacier changes also showed spatial differences, for example, glacier retreat rate was the fastest at glacier termini between 5400 and 5700 m a.s.l than at other elevations. The result also shows that glaciers in the middle Himalayas retreat almost at a same pace with those in the western Himalayas.

关键词： Glacier lake Remote Sensing Mr. Qomolangma region Himalayas Tibetan Plateau

A Practical Reconstruction Algorithm in 2D Industrial ct

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中国体视学与图像分析 2005年第3期 189-193页

作者： LI Hui 1,2, TIAN Jie 2, ZHAng ZhaoTian 3 (1. Department of Education Technology, Capital Normal University, Beijing, 100037, china 2. Medical Image Processing Group, key laboratory of Complex Systems and Intelligence science, Institute of Automation, chinese Academy of sciences, P.O.Box 2728, Beijing, 100080, china 3. Department of Information science, National Natural science Foundation of china, Beijing, 100085, china)

Computed tomography plays an important role in industrial non-destructive testing, medical applications, astronomy and many other fields to look inside the scanned obj.ct and to analysis its inner structures. A non-destructive testing software have been developed to efficiently detect inner flaws of space industrial components. As the core of our software, reconstruction algorithms including preprocess of raw data, re-arrange algorithm and filtered back-projection algorithms have been described in detail in this article. With real raw data from CASC of china, experimental results verified the applied reconstruction algorithm in our software. Furthermore, forward algorithms simulating generation of fan-beam raw data are also presented in this article.

关键词： Reconstruction algorithms industrial ct imaging data preprocess

ct examination, clinical situation and experimental characteristics of infants with intracranial hemorrhage induced by delayed vitamin K deficiency

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Neural Regeneration Research 2006年第9期1卷 801-805页

作者： Zhiqing Lin1, Feng Fang1, Min Chen2, Guoxiang Cai3 1Department of Pediatrics, Tongji Hospital Affiliated to Tongji Medical College, Huazhong University of science and Technology, Wuhan 430030, Hubei Province, china 2Department of Pediatrics, 3Department of Radiation Medicine, Zhongshan Hospital Affiliated to Xiamen University, Xiamen 361004, Fujian Province, china Department of Pediatrics Tongji Hospital Huazhong University of Science and Technology Wuhan 430030 Hubei Province China Department of pediatrics Zhongshan Hospital Xiamen University Xiamen 361004 Fujian Province China Department of Radiation Medicine Zhongshan Hospital Xiamen University Xiamen 361004 Fujian Province China

BACKGROUND: Delayed vitamin K deficiency is characterized by acute onset, severe illness and high fatality rate. 33%-50% survivors accompany with other various nervous system sequelas. Therefore, diagnosis and treatment of intracranial hemorrhage in time become a key factor for improving healing rate and reducing fatality rate and incidence of sequela. obj.ctIVE: To investigate the clinical situation, experimental characteristics, ct examination and terminative characteristics of infants with intracranial hemorrhage induced by delayed vitamin K deficiency. DESIGN: Case analysis. SETTIng: Department of Pediatrics, Zhongshan Hospital Affiliated to Xiamen University. PARTICIPANTS: A total of 17 infants with intracranial hemorrhage induced by delayed vitamin K deficiency aged 1-3 months including 11 boys and 6 girls were selected from Department of Pediatrics, Zhongshan Hospital Affiliated to Xiamen University from January 1994 to December 2005. All infants had drowsiness, rejective milk, spiting milk, gaze of both eyes, tic, coma, full anterior fontanelle, high muscular tension and cerebral hernia, etc. Experimental examination demonstrated that infants had anemia at various degrees; prothrombin time and partial thromboplastin time were prolonged; platelet count was normal. ct examination indicated that screenages of subarachnoid hemorrhage, subdural hematoma, cerebral parenchyma hemorrhage and intraventricular hemorrage were changed. Hemorrhage was stopped by the application of vitamin K. All patients provided informed consent. METHODS: ① Clinical situation and physical sign of infants were observed after hospitalization and scanned with rapid spiral ct scanning system. The thickness and average space of layers were 8-10 mm and the scanning time was 5 s with window width of 30-80 Hu and window position of 28-35 Hu. ② After hospitalization, four items of blood coagulation was measured with Futura meter and biochemical indexes of blood, such as serum calcium, serum alka

关键词： clinical situation and experimental characteristics of infants with intracranial hemorrhage induced by delayed vitamin K deficiency ct examination

都汶路恢复重建中的主要地震次生山地灾害与明洞工程

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山地学报 2011年第3期29卷 356-361页

作者：王全才王兰生李宗有王浩徐小林成都理工大学地质灾害防治与地质环境保护国家重点实验室中国科学院水利部成都山地灾害与环境研究所四川省交通厅交通勘察设计研究院

'5.12'汶川地震次生灾害中,有两类山地灾害至今仍对公路运营安全影响很大,其一是高高堆积在坡体之上且规模较大的松散(动)危岩体,其二是与岷江大致正交的泥石流沟泥石流。它们共同的特点是危险物源分布相对位置高、体量大、来势凶猛、... 详细信息

'5.12'汶川地震次生灾害中,有两类山地灾害至今仍对公路运营安全影响很大,其一是高高堆积在坡体之上且规模较大的松散(动)危岩体,其二是与岷江大致正交的泥石流沟泥石流。它们共同的特点是危险物源分布相对位置高、体量大、来势凶猛、冲击破坏性极强,加上它们发生的时间或空间的不确定性,致使常规防治措施无能为力并极易遭到破坏。复式明洞工程则是针对上述灾害专门提出的公路实用性防护工程。经过前期运行,已明显体现出这类工程的优越性,同时也凸显出一些尚需进一步改进的地方。

关键词：都汶路恢复重建复式明洞工程

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空间碎片减缓设计专家系统设计与实现

系统工程与电子技术 2008年第7期30卷 1355-1358页

作者：杜湘瑜朱炬波郭德强张影梁甸农国防科技大学电子科学与工程学院湖南长沙410073 国防科技大学理学院湖南长沙410073

设计并实现空间碎片减缓设计专家系统是深化空间碎片减缓技术研究的重要手段。围绕空间碎片减缓设计需求,提出了层次化的空间碎片减缓设计专家系统体系结构模型,并详细讨论了设计和实现过程中的各关键技术。原型系统的实现验证了体系结... 详细信息

设计并实现空间碎片减缓设计专家系统是深化空间碎片减缓技术研究的重要手段。围绕空间碎片减缓设计需求,提出了层次化的空间碎片减缓设计专家系统体系结构模型,并详细讨论了设计和实现过程中的各关键技术。原型系统的实现验证了体系结构和技术路线的可行性,为未来的深入细化奠定了基础。

关键词：空间碎片减缓设计专家系统知识库 Jess

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基于流域单元的泥石流区域危险性评价

山地学报 2006年第2期24卷 177-180页

作者：王晓朋潘懋徐岳仁北京大学造山带与地壳演化教育部重点实验室北京大学造山带与地壳演化教育部重点实验室北京大学地球与空间科学学院北京100871

进行泥石流区域危险性评价时,首先要选取合适的单元作为评价单元。在前人的研究成果中已有多种评价单元,如栅格单元、斜坡单元、单一条件单元等。作者认为国内评价工作中常采用的栅格单元、行政区划单元都没有体现泥石流发生特定的地貌... 详细信息

进行泥石流区域危险性评价时,首先要选取合适的单元作为评价单元。在前人的研究成果中已有多种评价单元,如栅格单元、斜坡单元、单一条件单元等。作者认为国内评价工作中常采用的栅格单元、行政区划单元都没有体现泥石流发生特定的地貌条件,故提出以流域为评价单元的思路。根据水文学D8方法,介绍了在计算机协助下基于DEM数据自动完成流域单元划分的方法,并以辽宁省鞍山市岫岩满族自治县作为实例,将全区划分为1024个流域单元。将流域划分结果与历史灾害点位置相对比,每个流域内基本上只包含一个灾害点,该情况说明流域划分精度满足研究工作需要。在此基础上利用人工神经网络进行泥石流区域危险性评价。结果显示,以流域作为评价单元能充分体现泥石流发生的地貌特征和物理机制,利于评价指标取值,而且危险性结果与实际情况吻合较好,可为政府部门制定减灾防灾决策提供参考。

关键词：泥石流区域危险性评价流域单元

Cost-Effective Machining of Granite by Reducing Tribological Interactions

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厦门大学学报（自然科学版） 2002年第S1期41卷 123-页

作者： LI Yuan 1, HUAng Hui 1, SHEN Jian-yun 1, XU Xi-peng 1, GAO Yong-sheng 2 (1. Province key Lab of Stone Machining, Huaqiao University, Quanzhou 362011, china 2. Department of Mechanical Engineering, Hong Kong University of science and T echnology, Hong Kong, china)

In order to implement cost-effective machining of gr anite materials with diamond impregnated tools, we should realize low tool w ear, low energy consumption, and high cutting efficiency, while the accuracy of the workpiece surfaces are maintained to be satisfactory. It is understood that the main factors affecting the tool wear, the energy, and the efficiency during the machining process are related to the tribological interactions that occur at the interface between the diamond tool surface and the workpiece. Based on this consideration, we propose a new machining method to machine granite materia ls to achieve improved cost effectiveness. In the proposed method, the tribologi cal interactions are maintained to a minimum. Based on the analyses of the experimental results, the following conclusions can be drawn: The wear performance is greatly dependent on the machining parameters and their combination. Therefore, optimum machining parameters must be set up at first in order to optimize the tribological characteristics of segments and thereby sawbl ade performance. These may be realized by balancing the energy expended by frict ion and the mechanical load on diamond crystal. The geometry and structure of diamond segments are another important criterion f or the diamond saw blade. Using a seven-layer structure for multi-blades sawin g and applying segments with side slots for trimming application had greatly red uced the frictions in the sawing processes. The wetting and bonding between diamonds and matrix alloys have been considered as the prerequisite for high wear performance of the segments. Diamonds coated w ith Ti-Cr alloy by a unique technique can effectively improve its wetting c apability and provide more storage space for debris, thereby reducing friction i nteractions.

关键词： granite sawing friction interaction cost-effe ctive

Expert consensus on drug treatment of chronic subdural hematoma

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chinese Neurosurgical Journal 2022年第1期8卷 51-59页

作者： Jianning Zhang chinese Society of Neurosurgery chinese Medical Association chinese Neurosurgical Critical Care Specialist Council Collaborational Group of chinese Neurosurgical Translational and Evidence-based Medicine Department of Neurosurgery Tianjin Medical University General HospitalTianjin 300052China key laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System Ministry of EducationTianjin 300052China Tianjin key laboratory of Injuries Variations and Regeneration of Nervous SystemTianjin 300052China Tianjin Neurological Institute Tianjin 300052China 不详

Chronic subdural hematoma(CSDH)is a chronic space-occupying lesion formed by blood accumulation between arachnoid and dura mater,which is usually formed in the third week after traumatic brain *** treatment is usually the first choice for patients with CSDH having a significant space-occupying *** of the patients showed good results of surgical treatment,but still some patients had a postoperative recurrence(the recurrence rate was up to 33%).Because CSDH is often seen in the elderly,patients are weak and have many basic *** risk of surgical treatment is high;serious complications and even death(the death rate is up to 32%)can often *** overall good prognosis rate of patients aged more than 90 years is 24%.The drug treatment can provide a safe and effective treatment for elderly patients who are weak,intolerable to surgery,or failed in ***-dose and long-term use of atorvastatin(20mg/d)is suggested for continuous treatment for at least 8 weeks,while low-dose and short-term use of dexamethasone can improve the therapeutic effect of atorvastatin on *** should undergo ct or MRI scanning at least one time within 2 weeks after the start of drug treatment.

关键词： CSDH treatment drug death