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孤立性肺结节:一过性动态增强灌注区域CT检测、一过性动态增强MR成像和FDGPET/CT的比较

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国际医学放射学杂志 2015年第2期 182-183页

作者： y.Ohno M.Nishio H.Koyama S.Seki M.Tsubakimoto y.fujisawa 赵芳 Advanced Biomedical Imaging Research Center Division of Functional and Diagnostic Imaging Research Department of Radiology Kobe University Graduate School of Medicine 7-5-2 Kusunokicho Chuo-ku Kobe Hyogo 650 -0017 Kobe Japan

摘要目的前瞻性地比较动态灌注区域CT检测、动态MR成像以及应用18F FDG的PET/CT在孤立性肺结节诊断中的能力。材料与方法机构审查委员会批准了这项研究,每

关键词：肺结节 PET 动态增强孤立性一过性 MR CT

Behavior of Vaneless Diffuser Stall in a Centrifugal Compressor

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Journal of Thermal Science 2022年第1期31卷 3-12页

作者： AGARI yuki yAMAO yoshifumi fujisawa Nobumichi OHTA yutaka Department of Applied Mechanics and Aerospace Engineering Waseda UniversityTokyo 169-8555Japan

The rotating stall in a centrifugal compressor with a vaneless diffuser was investigated both experimentally and numerically with focus on the effect of the internal flow field within the impeller on the diffuser *** numerical analysis,the boundary layer separation at the impeller outlet was found to play an important role in the expansion and rotation processes of the diffuser *** particular,the expanded boundary layer separation near the hub side at the outlet of the main blade(M.B.)suction surface passage was considered to be the main cause of the expansion and rotation processes.A longitudinal vortex existed at the throat of the ***,and the mass flow rate in the *** was significantly reduced by the blockage *** addition,the longitudinal vortex induced the rolling up flow near the hub side at the impeller ***,the boundary layer separation expanded.

关键词： centrifugal compressor vaneless diffuser pressure and velocity measurement CFD rotating stall

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十字路口上的日本动产担保法

苏州大学学报（法学版） 2024年第1期11卷 149-160页

作者： [日]藤泽治奈徐洁燕颖川(译) 立教大学法学部西南政法大学民商法学院

日本动产担保法的修改正面临着艰难的抉择。担保的法律形式的一元主义和多元主义的选择以及动产担保标的物范围的规定最为棘手。关于法律形式,无论是以美国为代表的一元主义,还是以法国为代表的多元主义实际都不是绝对的,日本担保法制... 详细信息

日本动产担保法的修改正面临着艰难的抉择。担保的法律形式的一元主义和多元主义的选择以及动产担保标的物范围的规定最为棘手。关于法律形式,无论是以美国为代表的一元主义,还是以法国为代表的多元主义实际都不是绝对的,日本担保法制部会的两种法案也不是对立的。所以,或许在法律形式上采用多元主义,而对任何形式的担保交易都采用同样的规则是实现实质性的一元主义的最好路径。关于担保标的物范围的扩张,其核心问题是,集合动产概念扩张的范围,如何处理因缓和集合动产的特定性要件而产生的一系列法律问题,以及企业营业资产成为担保客体的问题。同时,还要考虑一般实体法与破产法关于动产担保制度的协调。

关键词：动产担保法担保的法律形式担保标的物的范围

Geometric-phase-induced arbitrary polarization and orbital angular momentum generation in helically twisted birefringent photonic crystal fiber

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Photonics Research 2020年第8期8卷 1278-1288页

作者： TAKESHI fujisawa KUNIMASA SAITOH Graduate School of Information Science and Technology Hokkaido UniversityJapan

The evolutions of polarization and orbital angular momentum(OAM)states of light in helically twisted birefringent photonic crystal fibers(TB-PCFs)are *** is shown that a circular polarization(CP)component(S3 of a Stokes parameter)is periodically excited when usual linearly polarized(LP)modes of PCF are *** excitation originates from a geometric phase in *** S3 excitation is larger for larger linear birefringence for a fixed twisting *** the linear birefringence is large enough,a CP filtering behavior can be seen in addition to the S3 *** the analytical consideration of the sign of the geometric phase,the TB-PCF with periodical inversion of twisting is proposed to generate arbitrary polarization state on the Poincaré***,an OAM state generation in multimode TB-PCFs is shown for higher-order LP mode *** observing a far-field interference pattern from TB-PCF mixed with LP01 mode,a vortex associated with the OAM state can be *** to the single-mode case,by using periodical twisting inversion,efficient OAM generation is *** results indicate that by simply launching fiber’s LP mode into TB-PCF,arbitrary polarization and OAM states can be generated,leading to a novel mechanism for the manipulation of the spatial state of light.

关键词： polarization fiber momentum

Unsteady Behavior and Control of Vortices in Centrifugal Compressor

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Journal of Thermal Science 2014年第5期23卷 401-411页

作者： yutaka Ohta Nobumichi fujisawa Department of Applied Mechanics and Aerospace Engineering Waseda University3-4-1OkuboShinjukuTokyo169-8555Japan Graduate School of Fundamental Science and Engineering Waseda University3-4-1OkuboShinjukuTokyo169-8555Japan

Two examples of the use of vortex control to reduce noise and enhance the stable operating range of a centrifugal compressor are presented in this *** the case of high-flow operation of a centrifugal compressor with a vaned diffuser,a discrete frequency noise induced by interaction between the impeller-discharge flow and the diffuser vane,which appears most notably in the power spectra of the radiated noise,can be reduced using a tapered diffuser vane(TDV) without affecting the performance of the *** longitudinal vortices produced by leakage flow passing through the tapered portion of the diffuser vane induce secondary flow in the direction of the blade surface and prevent flow separation from the leading edge of the *** use of a TDV can effectively reduce both the discrete frequency noise generated by the interaction between the impeller-discharge flow and the diffuser surface and the broadband turbulent noise *** the case of low-flow operation,a leading-edge vortex(LEV) that forms on the shroud side of the suction surface near the leading edge of the diffuser increases significantly in size and blocks flow in the diffuser *** formation of an LEV may adversely affect the performance of the compressor and may cause the diffuser to *** a one-side tapered diffuser vane to suppress the evolution of an LEV,the stable operating range of the compressor can be increased by more than 12 percent,and the pressure-rise characteristics of the compressor can be *** results of a supplementary examination of the structure and unsteady behavior of LEVs,conducted by means of detailed numerical simulations,are also presented.

关键词：压缩机控制不稳定离心式行为涡流叶片表面扩散器离散频率

Unsteady Behavior of Leading-edge Vortex and Diffuser Stall in a Centrifugal Compressor with Vaned Diffuser

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Journal of Thermal Science 2016年第1期25卷 13-21页

作者： Nobumichi fujisawa Shotaro HARA yutaka OHTA Graduate Student Graduate School of Fundamental Science and EngineeringWaseda University 3-4-10kuboShinjukuTokyo 169-8555Japan Department of Applied Mechanics and Aerospace Engineering Waseda University 3-4-1 OkuboShinjukuTokyo 169-8555Japan

The characteristics of a rotating stall of an impeller and diffuser and the evolution of a vortex generated at the diffuser leading-edge(i.e., the leading-edge vortex(LEV)) in a centrifugal compressor were investigated by experiments and numerical analysis. The results of the experiments revealed that both the impeller and diffuser rotating stalls occurred at 55 and 25 Hz during off-design flow operation. For both, stall cells existed only on the shroud side of the flow passages, which is very close to the source location of the LEV. According to the CFD results, the LEV is made up of multiple vortices. The LEV is a combination of a separated vortex near the leading-edge and a longitudinal vortex generated by the extended tip-leakage flow from the impeller. Therefore, the LEV is generated by the accumulation of vorticity caused by the velocity gradient of the impeller discharge flow. In partial-flow operation, the spanwise extent and the position of the LEV origin are temporarily transmuted. The LEV develops with a drop in the velocity in the diffuser passage and forms a significant blockage within the diffuser passage. Therefore, the LEV may be regarded as being one of the causes of a diffuser stall in a centrifugal compressor.

关键词：叶片扩压器离心压缩机失速特性前缘涡扩散器稳态行为数值分析方法离心式压缩机

Gene expression during genital morphogenesis in the ground beetle Carabus maiyasanus

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Insect Science 2020年第5期27卷 975-986页

作者： Shota Nomura Tomochika fujisawa Teiji Sota Department of Zoology Graduate School of ScienceKyoto UniversitySakyoKyotoJapan

To investigate the developmental genetics of genital formation in the carabid beetle Carabus maiyasanus,we compared gene expression patterns among five stages using transcriptomic RNA sequencing data from abdominal segments and genitalia in the third(last)larval instar(including prepupa)and pupal *** identified 18839 genes,of which 10796 were differentially expressed among stages or between *** were relatively few differentially expressed genes(DEGs)between the sexes(3%).The DEGs were clustered into six groups,mainly according to stage-specific expression *** in clusters 1-3 showed high expression levels before pupation and low expression levels during the pupal period,whereas genes in clusters 46 showed high expression levels from the prepupal to the pupal *** related to the initial pupation process and differentiation of genital discs in Drosophila were involved in clusters 4 and 6 and showed low expression levels at early third instar and elevated expression levels from the early prepupal stage,suggesting that the pupation process and genital differentiation started in the prepupal *** 4 and 5 included developmental genes related to organ size control,which may be important in the formation of internal genital structures during the pupal stage.

关键词： Carabus genitalia Ohomopterus pupation RNA-seq transcriptome

Three-Dimensional Visualization of Shock Cell Structure and Screech Tone Emission in Underexpanded Circular Jet

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Journal of Flow Control, Measurement & Visualization 2022年第1期10卷 1-11页

作者： Keita Ozawa Takayuki yamagata Nobuyuki fujisawa Graduate School of Science and Technology Niigata University Niigata Japan Department of Mechanical Engineering Niigata University Niigata Japan Department of Mechanical Engineering Shinshu University Nagano Japan

The three-dimensional visualization of flow and screech-tone emission from an underexpanded circular jet is first investigated experimentally using high-speed cross-schlieren imaging and microphone measurements in the cross-sectional planes along the jet axis. This experimental technique allows the visualization of the shock-cell structure, directivity of sound intensity, and frequency spectrum in the cross-sectional planes of the screeching jet. The high-speed cross-schlieren observation of the screeching jet shows the occurrence of an asymmetrical shock-cell structure that is generated by the flapping mode in the screeching jet. This contributes to the generation of a screech tone propagating upstream along the jet axis and non-uniform sound intensities around the jet in circumferential direction. These observations by high-speed cross-yle="white-space:normal;font-size:10pt;font-family:"">schlieren imaging were validated by the microphone measurements.

关键词： Screech Tone Aeroacoustics Directivity Frequency Spectrum Underexpanded Circular Jet Schlieren Imaging

Development and Applications of Ruggedized VIS/NIR Spectrometer System for Oilfield Wellbores

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Photonic Sensors 2013年第4期3卷 289-294页

作者： Go fujisawa Tsutomu yAMATE Schlumberger GouM Research Cambridge UK Schlumberger K.K. Sagamihara Japan

The development and applications of a ruggedized visible to near-infrared (VIS/NIR) spectrometer system capable of measuring fluid spectra in oilfield wellbores are presented. Real-time assessment of formation fluid properties penetrated by an oilfield wellbore is critically important for oilfield operating companies to make informed decisions to optimize the development plan of the well and hydrocarbon reservoir. A ruggedized VIS/NIR spectrometer was designed and built to measure and analyze hydrocarbon spectra reliably under the harsh conditions of the oilfield wellbore environment, including temperature up to 175 °C, pressure up to 170 MPa, and severe mechanical shocks and vibrations. The accuracy of hydrocarbon group composition analysis was compared well with gas chromatography results in the laboratory.

关键词：近红外光谱仪油田应用系统加固井眼井筒流体光谱测量