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Effects of Diffuser Vane Geometry on Interaction Noise Generated from a Centrifugal Compressor

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Journal of Thermal science 2005年第4期14卷 321-328页

作者： Yutaka OHTA Naho TAKEHARA Yasuhiko OKUTSU Eisuke OUTA Department of Mechanical Engineering Waseda University 3-4-1 Okubo ShinjukuTokyo 169-8555Japan

The characteristics of interaction tone noise radiated from a centrifugal compressor with a vaned diffuser are discussed by experiments, including visualization techniques using the oil-film method. Research attention is paid to the leading edge geometries of the diffuser vanes that are deeply related to the generation mechanism of the interaction tone noise. The compressor-radiated noise can be reduced by several decibels by setting some clearances in both the hub and shroud surfaces of the diffuser wall along with some decline in the pressure-rise coefficient. Since the decline turned out to be caused by the flow impingement and also by the secondary flow within the diffuser passages, several new types of diffuser vane geometries which do not detract from both the performance and noise level are developed and utilized for the experiments. The presented diffuser vane geometries will offer a few basic guidelines for the diffuser vane design.

关键词： centrifugal compressor vaned diffuser interaction noise noise reduction.

Pressure Measurement on Casing Wall and Blade Rows Interaction of Contra-Rotating Axial Flow Pump

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Journal of Thermal science 2005年第2期14卷 142-149页

作者： Toru SHIGEMITSU Tomoya TAKANO Akinori FURUKAWA Kusuo OKUMA Satoshi WATANABE Division of Mechanical Engineering science Kyushu University 6-10-1HakozakiHigashi-kuFukuoka 812-8581JapanDivision of Mechanical Engineering Science Kyushu University6-10-1HakozakiHigashi-kuFukuoka 812-8581JapanDivision of Mechanical Engineering Science Kyushu University6-10-1HakozakiHigashi-kuFukuoka 812-8581JapanDivision of Mechanical Engineering Science Kyushu University6-10-1HakozakiHigashi-kuFukuoka 812-8581JapanDivision of Mechanical Engineering Science Kyushu University6-10-1HakozakiHigashi-kuFukuoka 812-8581Japan

An application of contra-rotating rotors has been proposed against a demand for developing higher specific speed axial flow pump. The blade rows interaction between front and rear rotors should be clarified for its stable operation and reduction of unsteady losses. In this paper, the static pressure distributions on casing wall are provided by measuring with the phase locked sampling method. The measurements are carried out for two types of the rear rotors with different blade number and chord length, and it is found that, for both types of rotors, the unsteady pressure fluctuations are more remarkable in the front rotor than in the rear rotor and they are caused by the rear rotor pressure field. The effects of pressure fluctuations will be discussed in more details toward understanding the blade rows interaction in the contra-rotating axial flow pump.

关键词：涡轮机逆旋转转子压力场叶栅交感测量方法

A measure for spatial heterogeneity of vegetation in the Center of Inner Mongolia

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Progress in Natural science:Materials International 2008年第3期18卷 289-295页

作者： Baimin Songa,b, Daming Huangc,d, Renqing Wanga, Shiyomi Masae d, Fei Xua, Wei Wanga, Gaosheng Zhanga, Xianqiang Zhanga, Jian Qiaoe a College of Life science, Shandong University, Jinan 250100, China b Department of Environmental science and Engineering, Tsinghua University, Beijing 100084, China c Institute of Ecology, Department of Biological sciences and Biotechnology, Tsinghua University, Beijing 100084, China d Faculty of science, Ibaraki University, Bunkyo 2-1-1, Mito 310-8512, japan e Department of Chemical Engineering, Tsinghua University, Beijing 100084, China College of Life science Shandong University Jinan 250100 China Department of Environmental science and Engineering Tsinghua University Beijing 100084 China Institute of Ecology Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China Faculty of science Ibaraki University Bunkyo 2-1-1 Mito 310-8512 Japan Department of Chemical Engineering Tsinghua University Beijing 100084 China

This study surveyed and analyzed the vegetation heterogeneity in the Center of Inner Mongolia (CIM) by a new method based on the beta-binomial distribution for each kind of vegetation. As many as 190 large quadrats of 5 mm 5 mm (representing an area of 50 km 50 km) (referred to as L-quadrats hereafter) were extracted from about an area of 475,000 km2. Each L-quadrat was divided into four small quadrats (S-quadrat) of 2.5 mm 2.5 mm (equivalent to 25 km 25 km) and the frequency of occurrence of each type of vegetation was recorded in each small quadrate. The weighted average heterogeneity from all of the vegetations composing a land- scape provides a measure at landscape level to determine the spatial intricateness of landscape composition. Our results indicated that each vegetation has its own distribution pattern and the degree of heterogeneity is different from one kind of vegetation to the other. The results proved that the beta-binomial distribution can be very useful for analyzing vegetation landscapes.

关键词： Heterogeneity Beta-binomial distribution Frequency Occurrence Inner Mongolia

Exact Controllability and Asymptotic Analysis for Shallow Shells

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Chinese Annals of Mathematics,Series B 2007年第1期28卷 93-122页

作者： S.KAIZU N.SABU Department of Mathematics Faculty of Education Ibaraki University 2-1-1BunkyoMitoJapanDepartment of Mathematics Faculty of EducationIbaraki University2-1-1BunkyoMitoJapan

The authors consider the exact controllability of the vibrations of a thin shallow shell, of thickness 2ε with controls imposed on the lateral surface and at the top and bottom of the shell. Apart from proving the existence of exact controls, it is shown that the solutions of the three dimensional exact controllability problems converge, as the thickhess of the shell goes to zero, to the solution of an exact controllability problem in two dimensions.

关键词： Exact controllability Asymptotic analysis Shallow shells

Microstructure effect on nanohardness distribution for medium-carbon martensitic steel

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science China(Technological sciences) 2006年第1期49卷 10-19页

作者： OHMURA Takahito TSUZAKI Kaneaki Steel Research Center National Institute for Materials Science Tsukuba 305-0047 Japan

Nanoindentation measurement was performed to evaluate the local hardness distribution for quenched and tempered martensitic steel with ferrite-cementite constituent. The ratio of standard deviation to the average nanohardness was 15.4% when nanoin-dentation tests were carried out at the peak load of 1000 μN, while that of the Vickers hardness was only 1.5% at 9.8 N. Electron backscatter diffraction analysis and SEM ob-servation all showed that the large scattering of nanohardness did not depend on the crystallographic orientation of each grain but from the inhomogeneous microstructure in the sub-micron scale such as cementite distribution. Compared with the results on tung-sten single crystals with different surface orientations as well as another martensite proc-essed by modified-ausforming with the same chemical composition but more homogene-ous cementite distribution, the nanohardness showed smaller scattering, supporting the conclusion.

关键词： martensitic steel, cementite, hardness distribution, nanoindentation.

Gallbladder cancer harboring ERBB2 mutation on the primary and metastatic site: A case report

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World Journal of Gastrointestinal Oncology 2019年第9期11卷 761-767页

作者： Chiaki Inagaki Daichi Maeda Akie Kimura Toru Otsuru Yoshifumi Iwagami Naohiro Nishida Daisuke Sakai Ryo Shitotsuki Shinichi Yachida Yuichiro Doki Taroh Satoh Department of Frontier science for Cancer and Chemotherapy Osaka University Graduate School of MedicineSuita 5650871OsakaJapan Department of Clinical Genomics Osaka University Graduate School of MedicineSuita 5650871OsakaJapan Gastroenterological Surgery Osaka University Graduate School of MedicineSuita 5650871OsakaJapan Center for Cancer Genomics and Personalized Medicine Osaka University Graduate School of MedicineSuita 5650871OsakaJapan Department of Cancer Genome Informatics Osaka University Graduate School of MedicineSuita 5650871OsakaJapan

BACKGROUND Bile duct cancer constitutes gallbladder cancer(GBC),intrahepatic cholangiocarcinoma(ICA),and extrahepatic cholangiocarcinoma(ECA).These three entities show morphological and immunohistochemical resemblance so that it is difficult to differentiate between primary ICA and liver metastasis of GBC,which sometimes becomes a point of discussion in clinical *** these cancers demonstrate significant differences in their mutational landscape,several reports demonstrated shared genomic alteration in paired primary and metastatic site aids in distinguishing metastatic recurrence from second primary *** SUMMARY We present a 73-year-old female patient who underwent curative resection for GBC harboring epidermal growth factor receptor 2(ERBB2)activating mutation on next-generation sequencing(NGS)-based genomic *** year later,a hepatic lesion was observed on follow-up imaging and she underwent surgical resection for a pathological *** histological findings of the hepatic lesion were similar to those of the primary ***,using NGS panel testing,the hepatic lesion was found to have ERBB2 activating mutation,which is the identical mutation detected in the sequencing result of the primary ***2 activating mutation occurs more frequently in GBC than ICA and ***,in the present case,we think this molecular finding potentiated the diagnosis of the liver mass toward a metastatic ***,this patient underwent HER2-targeted treatment with lapatinib in combination with capecitabin and obtained clinical *** This case illustrated NGS panel usefulness in distinguishing GBC recurrence from second primary cancer and HER2-targeted agent efficacy on ERBB2 mutated GBC.

关键词： Gall bladder cancer Bile duct cancer ERBB2 mutation Precision medicine Mutation-driven targeted treatment Case report

Dynamical model of HEV with two planetary gear units and its application to optimization of energy consumption

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science China(Information sciences) 2019年第12期62卷 194-206页

作者： Jiangyan ZHANG Shota INUZUKA Takafumi KOJIMA Tielong SHEN Junichi KAKO College of Mechanical and Electronic Engineering Dalian Minzu University Department of Engineering and Applied sciences Sophia University Higashi-Fuji Research Center Toyota Motor Corporation

A hybrid electric vehicle(HEV) that uses multiple planetary gear units with clutches as transmission system is advanced for the powertrain performance, because the operation of the clutches can lead to distinct operating modes, and the induced possible operating modes provide additional freedom to deal with the energy optimal control problem. Under each operating mode, the powertrain mechanical system has specific dynamical behavior. In order to develop model-based optimization schemes that can tackle the transient operations of the vehicle, exact dynamical modeling is investigated focusing on a hybrid powertrain system that uses a two-planetary-gear transmission box with two clutches. It shows that according to the states of the two clutches, the powertrain system has the power-split mode, parallel mode and the electric vehicle(EV) mode. Finally, an analysis for the calculation of the desired driving torque and its application to the dynamic programming(DP)-based energy management indicate the significance of the developed exact dynamical models.

关键词： hybrid electric vehicle two-planetary-gear modeling energy management dynamic programming

Rough set-based rule generation and Apriori-based rule generation from table data sets: a survey and a combination

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CAAI Transactions on Intelligence Technology 2019年第4期4卷 203-213页

作者： Hiroshi Sakai Michinori Nakata Graduate School of Engineering Kyushu Institute of TechnologySensui 1-1TobataKitakyushu 804-8550Japan Faculty of Management and Information science Josai International UniversityGumyoToganeChiba 283-0002Japan

The authors have been coping with new computational methodologies such as rough sets,information incompleteness,data mining,granular computing,etc.,and developed some software tools on association rules as well as new mathematical *** simply term this research Rough sets Non-deterministic Information Analysis(RNIA).They followed several novel types of research,especially Pawlak’s rough sets,Lipski’s incomplete information databases,Or?owska’s non-deterministic information systems,Agrawal’s Apriori *** are outstanding researches related to information incompleteness,data mining,and rule *** have been trying to combine such novel researches,and they have been trying to realise more intelligent rule generator handling data sets with information *** study surveys the authors’research highlights on rule generators,and considers a combination of them.

关键词： Apriori rule incomplete

Improving symbolic data visualization for pattern recognition and knowledge discovery

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Visual Informatics 2020年第1期4卷 23-31页

作者： Kadri Umbleja Manabu Ichino Hiroyuki Yaguchi School of science and Engineering Tokyo Denki UniversityHatoyamaSaitama 350-0394Japan

This paper examines the visualization of symbolic data and considers the challenges rising from its complex *** data is usually aggregated from large data sets and used to hide entry specific details and to transform huge amounts of data(like big data)into analyzable *** is also used to offer an overview in places where general trends are more important than individual *** data comes in many forms like intervals,histograms,categories and modal multi-valued *** data can also be considered as a ***,the de facto visualization approach for symbolic data is zoomstars which has many *** biggest limitation is that the default distributions(histograms)are not supported in 2D as additional dimension is *** paper proposes several new improvements for zoomstars which would enable it to visualize histograms in 2D by using a quantile or an equivalent interval *** addition,several improvements for categorical and modal variables are proposed for a clearer indication of presented *** for different approaches to zoomstars are offered depending on the data type and the desired ***,an alternative approach that allows visualizing the whole data set in comprehensive table-like graph,called shape encoding,is *** visualizations and their usefulness are verified with three symbolic data sets in exploratory data mining phase to identify trends,similar objects and important features,detecting outliers and discrepancies in the data.

关键词： Data visualization Symbolic data Zoomstar Shape encoding Exploratory data analysis