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| 1 | Multimodality treatment in hepatocellular carcinoma patients with tumor thrombi in portal vein显示文摘AIM To compare the therapeutic effect andsignificances of multimodality treatment forhepatocellular carcinoma (HCC) with tumorthrombi in portal vein (PVTT).METHODS HCC patients (n = 147) with tumortrombi in the main portal vein or the first branchof portal vein were divided into four groups bythe several therapeutic methods. There wereconservative treatment group in 18 out ofpatients (group A); and hepatic artery ligation(HAL) and/or hepatic artery infusion (HAl)group in 18 patients (group B), in whompostoberative chemoembolization was doneperiodically; group of removal of HCC with PVTTin 79 (group C) and group of transcatheterhepatic arterial chemoembolization (TACE) orHAl and/or portal vein infusion (PVI) afteroperation in 32 (group D).RESULTS The median survival period was 12months in our series and the 1-, 3-, and 5-yearsurvival rates were 44.3%, 24.5% and 15.2%,respectively. The median survival times were 2,5, 12 and 16 months in group A, B, C and D,respectively. The 1-, 3- and 5-year survival rateswere 5.6%, 0% and 0% in group A; 22.2%,5.6% and 0% in group B; 53.9%, 26.9% and16.6% in group C; 79.3%, 38.9% and 26.8% ingroup D, respectively. Significant differenceappeared in the survival rates among the groups(P<0.05).CONCLUSION Hepatic resection with removalof tumor thrombi and HCC should increase thecurative effects and be encouraged for theprolongation of life span and quality of life forHCC patients with PVTT, whereas the besttherapeutic method for HCC with PVTT is withregional hepatic chemotherapy orchemoemblization after hepatic resection withremoval of tumor thrombi. | Jia Fan Zhi Quan Wu Zhao You Tang Jian Zhou Shuang Jian Qiu Zeng Chen Ma Xin Da Zhou Sheng Long Ye Liver Cancer Institute, Zhongshan Hospital, Fudan University Medical Center (Former Shanghai University), 136 Yixueyuan Road, Shanghai 200032, China | 2001 | World Journal of Gastroenterology2001，7，1： | 80 |
| 2 | Combined detection of serum tumor markers for differential diagnosis of solid lesions located at the pancreatic head显示文摘BACKGROUND: The differential diagnosis of solid lesions located at the pancreatic head is very important for choosing therapies and setting up surgical tactics. This study was designed to evaluate the clinical significance of combined measurement of multiple serum tumor markers and the application of the receiver-operating characteristic (ROC) curves in the differential diagnosis of solid lesions located at the pancreatic head. METHODS: The serum levels of CA19-9, CA242, CA50 and carcinoembryonic antigen (CEA) in 112 patients with carcinoma of the pancreatic head and 38 patients with focal chronic pancreatitis in the pancreatic head were measured with ELISA. The sensitivity, specificity, positive likelihood ratio (PLR) and negative likelihood ratio (NLR) of the four serum tumor markers were calculated. The ROC curves for the four serum tumor markers were constructed and the area under the curve (AUC) was calculated. RESULTS: The AUCs of CA19-9, CA242, CA50 and CEA were 0.805, 0.749, 0.738 and 0.705; the PLRs were 1.91, 3.43, 5.09 and 5.46; and the NLRs were 0.41, 0.56, 0.59 and 0.71, respectively. Combined measurements increased the diagnostic specificity, and parallel combined testing increased the diagnostic sensitivity. CONCLUSIONS: Combined measurement of serum tumor markers CA19-9, CA242, CA50 and CEA is valuable in differential diagnosis of solid lesions located at the pancreatic head, and CA19-9 has the best diagnostic ability. Combined measurements can increase the specificity ofdiagnosis. Evaluation with the ROC curve is better than the sensitivity or specificity alone and the results are more integrated and objective. | Liao, Quan Zhao, Yu-Pei Yang, Ying-Chi Li, Li-Jun Long, Xiao Han, Shao-Mei | 2007 | Hepatobiliary & Pancreatic Diseases International2007，6，6： | 27 |
| 3 | A New Kind of Pilot Controlled Proportional Direction Valve with Internal Flow Feedback显示文摘Proportional direction valve is one of the most fundamental elements in electronic-hydraulic control technique. Its function is to control the operating speed, direction, position, and strength of output force of the hydraulic actuator continuously. Considering the different application and the cost, the existing technique mainly includes the internal feedback valve used in open loop system, and the electronic closed loop controlled valve used in closed loop system. Because of their different mechanical structure and the great different in performance, it brings inconvenience for customer to select, also inconvenience for enterprise to produce. Aiming at this problem, the idea of combining the above two kinds of valves into one body is proposed first, and then the new valve’s structure to realize this target is designed. The idea intends to apply the displacement pilot flow feedback control principle in present 2-position 2-way valve system to the proportional direction valve of 3-position 4-way system. Newly designed feed forward controller can decouple the interference between the internal feedback and the electronic closed loop. Redundant conversion is designed to electronic switch mode. Experiment on dynamic and static characteristic of new proportional direction valve in internal feedback control mode and electronic closed loop control mode is discussed to prove the new theory is correct. Although the new valve is of excellent dynamic response characteristic, its steady control characteristic in open loop control mode needs to be improved further. The research results prepare one new fundamental element for electronic-hydraulic control technology. | QUAN Long XU Xiaoqing YAN Zheng ZHANG Xiaojun | 2010 | Chinese Journal of Mechanical Engineering2010，23，1： | 22 |
| 4 | Excavator Energy-saving Efficiency Based on Diesel Engine Cylinder Deactivation Technology显示文摘The hydraulic excavator energy-saving research mainly embodies the following three measures: to improve the performance of diesel engine and hydraulic component, to improve the hydraulic system, and to improve the power matching of diesel-hydraulic system-actuator. Although the above measures have certain energy-saving effect, but because the hydraulic excavator load changes frequently and fluctuates dramatically, so the diesel engine often works in high-speed and light load condition, and the fuel consumption is higher. Therefore, in order to improve the economy of diesel engine in light load, and reduce the fuel consumption of hydraulic excavator, energy management concept is proposed based on diesel engine cylinder deactivation technology. By comparing the universal characteristic under diesel normal and deactivated cylinder condition, the mechanism that fuel consumption can be reduced significantly by adopting cylinder deactivation technology under part of loads condition can be clarified. The simulation models for hydraulic system and diesel engine are established by using AMESim software, and fuel combustion consumption by using cylinder-deactivation-technology is studied through digital simulation approach. In this way, the zone of cylinder deactivation is specified. The testing system for the excavator with this technology is set up based on simulated results, and the results show that the diesel engine can still work at high efficiency with part of loads after adopting this technology; fuel consumption is dropped down to 11% and 13% under economic and heavy-load mode respectively under the condition of driving requirements. The research provides references to the energy-saving study of the hydraulic excavators. | YANG Jing QUAN Long YANG Yang | 2012 | Chinese Journal of Mechanical Engineering2012，25，5： | 15 |
| 5 | The Impacts of Mosquito Density and Meteorological Factors on Dengue Fever Epidemics in Guangzhou, China, 2006-2014: a Time-series Analysis显示文摘Objective To explore the associations between the monthly number of dengue fever(DF) cases and possible risk factors in Guangzhou, a subtropical city of China. Methods The monthly number of DF cases, Breteau Index(BI), and meteorological measures during 2006-2014 recorded in Guangzhou, China, were assessed. A negative binomial regression model was used to evaluate the relationships between BI, meteorological factors, and the monthly number of DF cases. Results A total of 39,697 DF cases were detected in Guangzhou during the study period. DF incidence presented an obvious seasonal pattern, with most cases occurring from June to November. The current month's BI, average temperature(Tave), previous month's minimum temperature(Tmin), and Tave were positively associated with DF incidence. A threshold of 18.25 °C was found in the relationship between the current month's Tmin and DF incidence. Conclusion Mosquito density, Tave, and Tmin play a critical role in DF transmission in Guangzhou. These findings could be useful in the development of a DF early warning system and assist in effective control and prevention strategies in the DF epidemic. | SHEN Ji Chuan LUO Lei LI Li JING Qin Long OU Chun Quan YANG Zhi Cong CHEN Xiao Guang | 2015 | Biomedical and Environmental Sciences2015，28，5： | 12 |
| 6 | Stress-mediated p38 activation promotes somatic cell reprogramming显示文摘环境调停压力的改编在生活的进化起必要作用。细胞的改编机制通常包含染色质结构,抄写, mRNA 稳定性和翻译的规定,它最后在基因表示导致有效变化。全球 epigenetic 变化也涉及体的细胞的 reprogramming 进导致的 pluripotent 由定义因素的茎(iPS ) 细胞。这里,我们报导象 hyperosmosis 那样的那个环境压力不仅便于四调停因素的 reprogramming,而且提高二或一导致因素的 iPS 房间代。导致 Hyperosmosis 的 p38 激活在这个过程起一个关键作用。组成的活跃 p38 模仿 hyperosmosis 的积极效果,当主导的否定 p38 和 p38 禁止者堵住 hyperosmosis 的效果时。进一步的学习显示调停压力的 p38 激活可以由减少全球 DNA methylation 水平并且提高 pluripotency 基因的表示支持 reprogramming。我们的结果表明象 hyperosmosis 一样的简单环境应力怎么帮助经由细胞内部的发信号和 epigenetic 调整改变房间的命运。 | Xinxiu Xu Quan Wang Yuan Long Ru Zhang Xiaoyuan Wei Mingzhe Xing Haifeng Gu Xin Xie | 2013 | Cell Research2013，23，1： | 12 |
| 7 | Casticin induces caspase-mediated apoptosis via activation of mitochondrial pathway and upregulation of DR5 in human lung cancer cells显示文摘Objective:To assess if casticin induces caspase-mediated apoptosis via activation of mitochondrial pathway and upregulation of DR5 in human lung cancer ceils.Methods:Human non-small-cell lung carcinoma cell lines H460,AS49 and H157 were cultured in vitro.The cytotoxic activities were determined using MTT assay.The apoptotic cells death was examined by flow cytometry using PI staining and DMA agarose gel electrophoresis.The activities of caspase-3, -8 and -9 were measured via ELISA.Cellular fractionation was determined by flow cytometry to assess release of cytochrome c and the mitochondrial transmembrane potential.Bcl-2/Bcl-XL/ XIAP/Bid/ DR5 and DR4 proteins were analyzed using western blot.Results:The concentrations required for a 50%decrease in cell growth(IC50) ranged from 1.8 to 3.2 Jt M.Casticin induced rapid apoptosis and triggered a series of effects associated with apoptosis by way of mitochondrial pathway,including the depolarization of the mitochondrial membrane,release of cytochrome c from mitochondria,activation of procaspase-9 and -3,and increase of DNA fragments.Moreover, the pan caspase inhibitor zVAD-FMK and the caspase-3 inhibitor zOEVD-FMK suppressed casticin-induced apoptosis.In addition,casticin induced XIAP and Bcl-XL down-regulation, Bax upregulation and Bid clearage.In H157 cell line,casticin increased expression of DRS at protein levels but not affect the expression of DR4.The prelreatmenl with DR5/Fc chimera protein effectively attenuated casticin-induced apoptosis in H157 cells.No correlation was found between cell sensitivity to casticin and that to p53 status,suggesting that casticin induce a p53- independent apoptosis.Conclusions:Our results demonstrate that casticin induces caspase-mediated apoptosis via activation of mitochondrial pathway and upregulation of DRS in human lung cancer cells. | Yuan Zhou Yi Peng Qi-Qi Mao Xia Li Ming-Wu Chen Ting Su Li Tian Nai-Quan Mao Ling-Zhi Long Mei-Fang Quan Fei Liu Su-Fang Zhou Yong-Xiang Zhao | 2013 | Asian Pacific Journal of Tropical Medicine2013，6，5： | 11 |
| 8 | Genome size and sequence composition of moso bamboo: A comparative study显示文摘Moso bamboo (Phyllostachys pubescens) is one of the world's most important bamboo species. It has the largest area of all planted bamboo―over two-thirds of the total bamboo forest area―and the highest economic value in China. Moso bamboo is a tetraploid (4x=48) and a special member of the grasses family. Although several genomes have been sequenced or are being sequenced in the grasses family, we know little about the genome of the bambusoids (bamboos). In this study, the moso bamboo genome size was estimated to be about 2034 Mb by flow cytometry (FCM), using maize (cv. B73) and rice (cv. Nipponbare) as internal references. The rice genome has been sequenced and the maize genome is being sequenced. We found that the size of the moso bamboo genome was similar to that of maize but significantly larger than that of rice. To determine whether the bamboo genome had a high proportion of repeat elements, similar to that of the maize genome, approximately 1000 genome survey sequences (GSS) were generated. Sequence analysis showed that the proportion of repeat elements was 23.3% for the bamboo genome, which is significantly lower than that of the maize ge-nome (65.7%). The bamboo repeat elements were mainly Gypsy/DIRS1 and Ty1/Copia LTR retrotrans-posons (14.7%), with a few DNA transposons. However, more genomic sequences are needed to con-firm the above results due to several factors, such as the limitation of our GSS data. This study is the first to investigate sequence composition of the bamboo genome. Our results are valuable for future genome research of moso and other bamboos. | GUI YiJie1, WANG Sheng1, QUAN LiYan1, ZHOU ChangPing2, LONG ShiBao2, ZHENG HuaJun3, JIN Liang1, ZHANG XianYin 1, MA NaiXun 4 & FAN LongJiang1 1 Institute of Crop Science/Institute of Bioinformatics, Zhejiang University, Hangzhou 310029, China 2 Zhejiang Anji Bamboo Exposition Garden, Anji 313300, China 3 Chinese National Human Genome Center at Shanghai, Shanghai 201203, China 4 The Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Fuyang 311400, China | 2007 | Science China(Life Sciences)2007，50，5： | 10 |
| 9 | 抗血管生成因子Angiostatin与Endostatin作用下肿瘤血管生成的二维数值模拟显示文摘目的数值模拟抗血管生成因子Angiostatin和Endostatin对肿瘤血管生成的影响。方法建立肿瘤内外血管生成的二维离散数学模型。模型耦合两种抗血管生成因子Angiostatin和Endostatin的抑制效应,数值模拟在促血管生成因子诱导下肿瘤微血管网生成,讨论血管生成抑制因子的影响。结果抗血管生成因子Angiostatin对肿瘤内外血管网络生成的速度和成熟度有抑制作用。抗血管生成因子Angiostatin和Endostatin耦合作用时,在肿瘤血管生成的早期有明显的抑制效应;在肿瘤血管生成的中后期,它们可以降低肿瘤血管化程度。结论本文模型能够较好的模拟抗血管生成因子Angiostatin和Endostatin对内皮细胞迁移和增殖的抑制作用。 | 赵改平 高昊 吴洁 许世雄 Collins MW LONG Quan Carola Koenig Padhani AR | 2006 | 医用生物力学2006，21，4： | 10 |
| 10 | Output Characteristics of a Series Three-port Axial Piston Pump显示文摘Driving a hydraulic cylinder directly by a closed-loop hydraulic pump is currently a key research area in the field of electro-hydraulic control technology,and it is the most direct means to improve the energy efficiency of an electro-hydraulic control system.So far,this technology has been well applied to the pump-controlled symmetric hydraulic cylinder.However,for the differential cylinder that is widely used in hydraulic technology,satisfactory results have not yet been achieved,due to the asymmetric flow constraint.Therefore,based on the principle of the asymmetric valve controlled asymmetric cylinder in valve controlled cylinder technology,an innovative idea for an asymmetric pump controlled asymmetric cylinder is put forward to address this problem.The scheme proposes to transform the oil suction window of the existing axial piston pump into two series windows.When in use,one window is connected to the rod chamber of the hydraulic cylinder and the other is linked with a low-pressure oil tank.This allows the differential cylinders to be directly controlled by changing the displacement or rotation speed of the pumps.Compared with the loop principle of offsetting the area difference of the differential cylinder through hydraulic valve using existing technology,this method may simplify the circuits and increase the energy efficiency of the system.With the software SimulationX,a hydraulic pump simulation model is set up,which examines the movement characteristics of an individual piston and the compressibility of oil,as well as the flow distribution area as it changes with the rotation angle.The pump structure parameters,especially the size of the unloading groove of the valve plate,are determined through digital simulation.All of the components of the series arranged three distribution-window axial piston pump are designed,based on the simulation analysis of the flow pulse characteristics of the pump,and then the prototype pump is made.The basic characteristics,such as the pressure,flow and noise of the pumps under different rotation speeds,are measured on the test bench.The test results verify the correctness of the principle.The proposed research lays a theoretical foundation for the further development of a new pump-controlled cylinder system. | ZHANG Xiaogang QUAN Long YANG Yang WANG Chengbin YAO Liwei | 2012 | Chinese Journal of Mechanical Engineering2012，25，3： | 10 |
| 11 | Power Matching and Energy Efficiency Improvement of Hydraulic Excavator Driven with Speed and Displacement Variable Power Source显示文摘Mobile machinery energy efficiency and emission pollution are the national and worldwide issues. This paper contributes in solving these problems by applying a speed variable power source. Unfortunately, almost all of the speed variable systems have the dynamic response problem when the motor starts with full load or heavy load. To address this problem, a hydraulic accumulator is used to balance the load of the power source for assisting starting of the motor and a matching method combined with speed and displacement control of the pump is proposed to improve the energy efficiency and dynamic performance simultaneously under different working conditions. Also, the power source/valve combined control strategy of an independent metering system is designed to realize flow matching of the whole system. Firstly, a test system is established to study the dynamic performance and energy efficiency of the speed variable power source with an auxiliary accumulator. Working performance and energy consumption of the power source under different rotating speeds and different loads are studied. And then, the hydraulic excavator test rig with the proposed system is constructed. Furthermore, the working performance of the excavator with the speed-fixed and speed-variable strategy are studied comparatively. Results show that, compared with fixed-speed strategy, the electric power consumption during the idle period and partial load condition can be reduced about 2.05 kW and 1.37 kW. The energy efficiency of speed variable power source is about 40%-71%, which is higher than that of the fixed-speed power source by 3%–10%. | Lei Ge Long Quan Xiaogang Zhang Zhixin Dong Jing Yang | 2019 | Chinese Journal of Mechanical Engineering2019，32，6： | 10 |
| 12 | New Method to Improve Dynamic Stiffness of Electro-hydraulic Servo Systems显示文摘Most current researches working on improving stiffness focus on the application of control theories.But controller in closed-loop hydraulic control system takes effect only after the controlled position is deviated,so the control action is lagged.Thus dynamic performance against force disturbance and dynamic load stiffness can't be improved evidently by advanced control algorithms.In this paper,the elementary principle of maintaining piston position unchanged under sudden external force load change by charging additional oil is analyzed.On this basis,the conception of raising dynamic stiffness of electro hydraulic position servo system by flow feedforward compensation is put forward.And a scheme using double servo valves to realize flow feedforward compensation is presented,in which another fast response servo valve is added to the regular electro hydraulic servo system and specially utilized to compensate the compressed oil volume caused by load impact in time.The two valves are arranged in parallel to control the cylinder jointly.Furthermore,the model of flow compensation is derived,by which the product of the amplitude and width of the valve's pulse command signal can be calculated.And determination rules of the amplitude and width of pulse signal are concluded by analysis and simulations.Using the proposed scheme,simulations and experiments at different positions with different force changes are conducted.The simulation and experimental results show that the system dynamic performance against load force impact is largely improved with decreased maximal dynamic position deviation and shortened settling time.That is,system dynamic load stiffness is evidently raised.This paper proposes a new method which can effectively improve the dynamic stiffness of electro-hydraulic servo systems. | BAI Yanhong QUAN Long | 2013 | Chinese Journal of Mechanical Engineering2013，26，5： | 9 |
| 13 | Mathematical Model of Hydrodynamic Torque Converter and Analytic Description of Streamline显示文摘The mathematical model of a 3-element centripetal-turbine hydrodynamic torque converter and analytic description of fluid flow inside the hydrodynamic torque converter are investigated.A new torus coordinate system is proposed so as to quantitatively describe fluid movement inside the hydrodynamic torque converter.The particle movement inside the hydrodynamic torque converter is decomposed into meridional component movement and torus component movement, and a universal meridional streamline equation is derived.According to the relationship between the converter wheel velocity polygon and its blade angle, a torus streamline differential equation is established.The universal meridional streamline equation is approximated with square polynomials.The approximation error curve is given and the percentage error is not greater than 0.86%.Considered as a function of polar angle, the blade angle cotangent of each converter wheel varies linearly with polar angle.By using integral calculus, torus streamline equations are obtained.As a result, the problem of difficult flow description of the hydrodynamic torque converter is solved and a new analytic research system is established. | LIU Shiping QUAN Long | 2009 | Chinese Journal of Mechanical Engineering2009，22，1： | 7 |
| 14 | Synthesis and application of a hydrophobic hypercrosslinked polymeric resin for removing VOCs from humid gas stream显示文摘恐水病的亢奋的 crosslinked 聚合树脂 LC-1 被准备并且描绘。LC-1 树脂的性质与商业亢奋的 crosslinked 聚合物 NDA-201 树脂的那些相比。另外, trichloroethylene (TCE ) 的动态吸附被调查到在在 303 K 的干燥、潮湿的条件下面的 LC-1 上, LC-1 拥有的结果表演高恐水病的性质和罐头把 TCE 从气体移开没有高湿度的效果,高效地流。 | Peng Liu Chao Long Hong Ming Qian Ying Li Ai Min Li Quan Xing Zhang | 2009 | Chinese Chemical Letters2009，20，4： | 7 |
| 15 | Flow Control for a Two-Stage Proportional Valve with Hydraulic Position Feedback显示文摘The current research mainly focuses on the flow control for the two-stage proportional valve with hydraulic position feedback which is named as Valvistor valve.Essentially,the Valvistor valve is a proportional throttle valve and the flow fluctuates with the change of load pressure.The flow fluctuation severely restricts the application of the Valvistor valve.In this paper,a novel flow control method the Valvistor valve is provided to suppress the flow fluctuation and develop a high performance proportional flow valve.The mathematical model of this valve is established and linearized.Fuzzy proportional-integral-derivative(PID)controller is adopted in the closed-loop flow control system.The feedback is obtained by the flow inference with back-propagation neural network(BPNN)based on the spool displacement in the pilot stage and the pressure differential across the main orifice.The results show that inference with BPNN can obtain the flow data fast and accurately.With the flow control method,the flow can keep at the set point when the pressure differential across the main orifice changes.The flow control method is effective and the Valvistor valve changes from proportional throttle valve to proportional flow valve.For the developed proportional flow valve,the settling time of the flow is very short when the load pressure changes abruptly.The performances of hysteresis,linearity and bandwidth are in a high range.The linear mathematical model can be verified and the assumptions in the system modeling is reasonable. | He Wang Xiaohu Wang Jiahai Huang Long Quan | 2020 | Chinese Journal of Mechanical Engineering2020，33，6： | 6 |
| 16 | Sequential analysis of dimethyl sulfur compounds in seawater显示文摘为暗淡乙醇硫的化合物,包括的 dimethylsulfide (数据管理系统) , dimethylsulfoniopropionate (DMSP ) 和 dimethylsulfoxide (DMSO ) 的决心的一个顺序的方法,在海水,样品被开发了。在 25 mL 样品的数据管理系统的 2.5 pmol 的检测极限,相应于 0.10 nmol/L,被完成。为暗淡乙醇硫的化合物的恢复在范围 68.6 78.3% 。为数据管理系统, DMSP 和 DMSO 决心的相对标准偏差(R.S.D.s ) 分别地是 3.0, 5.4 和 7.4% 。 | Meng Li Dong Xing Yuan Quan Long Li Xiao Ying Jin | 2007 | Chinese Chemical Letters2007，18，1： | 6 |
| 17 | Numerical simulation of tumor-induced angiogenesis influenced by the extra-cellular matrix mechanical environment显示文摘To investigate tumor-induced angiogenesis underthe influence of the mechanical environments inside and outsidethe tumor, mathematical model of tumor angiogenesiswas developed. In the model, extra-cellular matrix (ECM)was treated as a thin plane. The displacement of ECM isobtained from the force balance equation consisted of theECs traction, the ECM visco-elastic forces and the externalforces. Simulation results show that a layered capillarynetwork is obtained with a well vascularized region at theperiphery of the tumor. The present model can be used asa valid theoretical method in the basic researches in tumor-inducedangiogenesis. | Yan Cai Kalkabay Gulnar Hongyi Zhang Jinfeng Cao Shixiong Xu Quan Long | 2009 | Acta Mechanica Sinica2009，25，6： | 5 |
| 18 | Segmentation of Tumor Ultrasound Image via Region-Based Ncut Method显示文摘To segment the tumor region precisely is a prerequisite for ultrasound navigation and treatment. In this paper, a normalized cut method to segment tumor ultrasound image is proposed by means of simple linear iterative clustering for presegmentation procedure. The first step, we use simple linear iterative clustering algorithm to divide the image into a number of homogeneous over-segmented regions. Then, these regions are regarded as nodes, and a similarity matrix is constructed by comparing the histograms of each two regions. Finally, we apply the Ncut method to merging the over-segmented regions, then the image segmentation process is completed. The results show that the proposed segmentation scheme handles the strong speckle noise, low contrast, and weak edges well in ultrasound image. Our method has high segmentation precision and computation efficiency than the pixel-based Ncut method. | QUAN Long ZHANG Dong YANG Yan LIU Yu QIN Qianqing | 2013 | Wuhan University Journal of Natural Sciences2013，18，4： | 5 |
| 19 | 先导数字调速阀特性分析(英文)显示文摘Flow control valve generally consists of constant pressure difference reducing valve and throttle valve.When it works under the condition of high differential pressure and flow, the pressure loss of reducing valve in-stalled in main loop will get increased and the hydraulic oil temperature will be increased as well. A digital pilotflow control valve is studied in this paper. The main stage is a cartridge valve based on the flow amplifying princi-ple. The pilot stage is digital flow control valve which consists of digital valve and constant pressure difference re-ducing valve. The digital valve controlled by PWM signal has some characteristics such as less throttling loss andgood repeatability. The high pressure loss and hydraulic oil temperature will be effectively reduced by using con-stant pressure difference reducing valve in the small flow pilot circuit. Through theoretical derivation and simula-tion research, the feasibility of this valve is verified, and some conclusions are drawn for the relationships betweenthe performance and structure parameters, which provides theoretical basis for their design. | Xiao-xia GUO Tao- tao LI Jia-hai HUANG Long QUAN Sheng-guo WANG | 2016 | 机床与液压2016，44，6： | 4 |
| 20 | First Oligocene mummified plant Lagerst?tte at the low latitudes of East Asia显示文摘Mummified fossils are extraordinarily important for understanding both biotic evolution and ecology in the geological time,by uniquely providing a far more detailed source of information in comparison to impression materials.However,mummified fossils are extremely rare because of the inevitable requirement of unusual preservation conditions during fossilization,including the lithological features and deposition rate of surrounding rocks,and moisture and temperature conditions(Taylor et al.,2009).To date,only a few Cenozoic sites have been reported to yield mummified plant fossils around the world,such as the middle | QUAN Cheng FU Qiong Yao SHI Gong Le LIU Yu Sheng LI Long LIU Xiao Yan JIN Jian Hua | 2016 | Science China Earth Sciences2016，59，3： | 4 |
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