检索结果-南通市图书馆

Functionally graded Al_2O_3-ZrO_2 composite prepared by centrifugal slip casting and its mechanical properties

在线全文

学校读者我要写书评

暂无评论

材料与冶金学报 2006年第4期5卷 296-299页

作者： hayakawa motozo HARA Yasuyuki LI Xiao-dong ONDA Tetsuhiko Department of Mechanical Engineering Tottofi University Koyama Tottofi 680 - 8552 Japan Graduate student Tottofi University Koyama Tottofi 680 -8552 Japan The Key Laboratory for Anisotropy and Texture of Materials （Ministry of Education） Northeastern University Shenyang 110004 China

Compositionally graded composite of alumina-20%zirconia (volume fraction) was fabricated by using centrifugal casting incorporated with relatively thin slip. An EPMA analysis exhibited a nearly linear variation of the alumina/zirconia ratio along the centrifugal direction; zirconia tended to accumulate in the bottom section, while alumina in the top section. Such a graded structure exhibited a considerably higher flexural strength when the alumina rich surface was subjected to a tensile stress than compositionally uniform composite of the same average composition. Fracture toughness measurement across the specimen thickness by indentation method revealed that the crack lengths along the vertical and horizontal directions were different. The anisotropy of the fracture toughness was accounted for by the variation of the residual stress across the specimen thickness.

关键词： Al2O3-ZrO2 复合材料离心滑动铸件弯曲强度

A new electric field mill array with each of the mill’s rotor controlled precisely by a GPS module:Equipment and initial results

在线全文

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2024年第2期8卷 423-435页

作者： Kozo Yamashita Hironobu Fujisaka DaoHong Wang Hiroyuki Iwasaki Kazuo Yamamoto Koichiro Michimoto Masashi hayakawa Department of Production Systems Engineering and Sciences Komatsu UniversityNu 1-3 Shicho-machiKomatsuIshikawa 923-8511Japan Fujisaka Technology Office 1058-5 Yoshizawa-choOhta-shiGunma 373-0019Japan Department of Electrical Electronic and Computer EngineeringGifu University1-1 YanagidoGifu CityGifu 501-1193Japan Cooperative Faculty of Education Gunma University4-2-Aramaki-machiMaebashiGunma 371-8510Japan Department of Electrical and Electronic Engineering Chubu University1200 Matsumoto-choKasugaiAichi 487-8501Japan Independent Researcher Kosenba Town 2-44-11-406Kawagoe CitySaitama350-0036Japan Advanced Wireless&Communications Research Center The University of Electro-Communications1-5-1 ChofugaokaChofuTokyo 182-8585Japan

We have newly designed an electrostatic sensor,called an electric field mill(EFM),to simplify the estimation of the charge position and charge amount transferred by lightning *** is necessary for this remote estimation of the transferred charge to measure electric field changes caused by charge loss at the time of a lightning strike at multiple *** multiple-station measurement of electric field changes,not only speed but also phase for exposure and shielding of the sensing plates inside each EFM of the array should be synchronized to maintain the sensitivities of the deployed ***,there is no such EFM with specified speed and phase control performance of the rotary ***,we developed a new EFM in which the rotary mechanism was controlled consistently to within 3%error by a GPS *** EFMs had been distributed in the Hokuriku area of Japan during the winter season of 2022-2023 for a test *** we describe the design and a simple calibration method for our new EFM *** analysis method based on the assumption of a simple monopole charge structure is also *** validation,locations of assumed point charges were compared with three-dimensional lightning mapping data estimated by radio observations in the MF-HF *** results indicated the validity to estimate transferred charge amounts and positions of winter cloud-to-ground lightning discharges with our new EFM array.

关键词： lightning electrostatic field electric field mill electric field change

Variations of Atmospheric ELF/VLF Radio Noise Due to Seismogenic Modifications in Tropospheric Conductivity

在线全文

学校读者我要写书评

暂无评论

Open Journal of Earthquake Research 2024年第2期13卷 113-132页

作者： Masashi hayakawa Alexander P. Nickolaenko hayakawa Institute of Seismo Electromagnetics Co. Ltd. (Hi-SEM) UEC Alliance Center #521 Tokyo Japan The University of Electro-Communications (UEC) Advanced Wireless & Communications Research Center (AWCC) Chofu-shi Tokyo O.Ya. Usikov Institute for Radiophysics and Electronics National Academy of Sciences of the Ukraine Kharkov Ukraine

We suggest a possible explanation of the influence of pre-seismic activity on the registration rate of natural ELF(extremely low frequency)/VLF(very low frequency) pulses and the changes of their characteristics. The main idea is as follows. The distribution of the electric field around a thundercloud depends on the conductivity profile of the atmosphere. Quasi-static electric fields of a thundercloud decrease in those tropospheric regions where an increase of air conductivity is generated by pre-seismic activities due to emanation of radioactive gas and water into the lower atmosphere. The electric field becomes reduced in the lower troposphere, and the probability decreases of the cloud-to-ground (CG) strokes in such “contaminated” areas. Simultaneously, the electric field grows inside and above the thunderclouds, and hence, we anticipate a growth in the number of horizontal and tilted inter-cloud (or intra-cloud) (both termed as IC discharges) strokes. Spatial orientation of lightning strokes reduces vertical projection of their individual amplitudes, while the rate (median number strokes per a unit time) of discharges grows. We demonstrate that channel tilt of strokes modifies the spectral content of ELF/VLF radio noise and changes the rate of detected pulses during the earthquake preparation phase.

关键词： ELF/VLF Radio Noise Earthquake Precursor Pre-Seismic Modification Conductivity Anomaly in the Lower Atmosphere Radioactive Radon Gases CG Lightning Discharges IC Discharges Cloud-to-Ionosphere Discharge

Isothermal and athermal martensitic transformations of ceria cerla doped zilrconian

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

材料与冶金学报 2010年第3期9卷 211-216页

作者：音田哲彦原纯平陈中春早川元造日本鸟取大学 Graduate Student of Mechanical and Aerospace Engineering Tottori University Sumitomo Electric Sintered Alloy Ltd.

Martensitic transformation behavior was studied for zirconia containing 4%～10% CeO2 (in mole fraction) by using a dilatometric method. The Ms (Martensite start temperature) decreased near linearly with increasing CeO2. Different transformation modes were observed depending on the composition and cooling rate. ZrO2 containing 6% CeO2 showed isothermal transformation behavior, whereas ZrO2 containing 9% and 10% CeO2 showed athermal transformation behavior. However, ZrO2 containing 8% CeO2 showed either isothermal or athermal transformations behavior depending on the cooling rate. A TTT (Time-Temperature-Transformation) diagram was proposed for ZrO2 containing 8% CeO2.

关键词： martensitic transformation ceria doped zirconia isothermal transformation athermal transformation thermally activated process burst type transformation

Malnutrition and Its Association with the Mortality of Patients with Femoral Intertrochanteric Fractures: A Retrospective Analysis of Japanese Patients

在线全文

学校读者我要写书评

暂无评论

Open Journal of Orthopedics 2024年第1期14卷 22-31页

作者： Taizo Kaneko Kyoko Matsudaira Kentaro hayakawa Fumiaki Tokimura Tsuyoshi Miyazaki Department of Orthopaedic Surgery Tokyo Metropolitan Institute for Geriatrics and Gerontology Tokyo Japan

Background: The incidence of femoral intertrochanteric fractures in older adults is higher than that of femoral neck fractures;however, both conditions are often analyzed together as proximal femoral fractures. Considering the difference in treatment, postoperative complication, and mortality risk, these two fractures should be analyzed separately. This study aimed to analyze 1-year mortality and its risk factors in patients with surgically treated femoral intertrochanteric fractures. Methods: Consecutive patients with intertrochanteric fractures who underwent surgical interventions at our institution between January 2017 and December 2021 were retrospectively reviewed. A total of 238 patients were eligible for inclusion in this study. Patients’ demographic and clinical information were retrospectively collected. Patients were divided into the 1-year mortality (n = 16) and survival (n = 222) groups. The incidence of 1-year mortality and its independent risk factors were investigated using univariate and multivariate logistic regression analyses. Results: The mean age of patients was 85.6 ± 8.5 years. The 1-year mortality rate was 6.7% (16/238). Preoperative albumin level, the Geriatric Nutritional Risk Index (GNRI), and malnutrition status (GNRI p = 0.02, p = 0.02, and p = 0.0011, respectively). Multivariate analysis showed that malnutrition status (GNRI p = 0.035) was an independent risk factor for 1-year mortality. Conclusion: Malnutrition status assessed using GNRI (GNRI < 92) was an independent risk factor for 1-year mortality. Our findings suggest that GNRI may be an effective screening tool for predicting postoperative 1-year mortality of patients with surgically treated femoral intertrochanteric fractures.

关键词： Intertrochanteric Fracture Mortality Geriatric Nutritional Risk Index Malnutrition Risk Factor

Isothermal and athermal type martensitic transformations in yttria doped zirconia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

材料与冶金学报 2005年第2期4卷 126-126页

作者：早川元造 PEE Jae-hwan 日本鸟取大学工学部 Graduate student

The phase transformation from the high temperature tetragonal phase to the low temperature monoclinic phase of zirconia had been long considered to be a typical athermal martensitic transformation until it was recently identified to be a fast isothermal transformation. The isothermal nature becomes more apparent when a stabilizing oxide, such as yttria, is doped, by which the transformation temperature is reduced and accordingly the transformation rate becomes low. Thus it becomes easy to experimentally establish a C-curve nature in a TTT （Time-Temperature-Transformation） diagram. The C-curve approaches that of well known isothermal transformation of Y-TZP （Yttria Doped Tetragonal Zirconia Polycrystals）, which typically contains 3mol% of *** principle, an isothermal transformation can be suppressed by a rapid cooling so that the cooling curve avoids intersecting the C-curve in TTT diagram. Y-TZP is the case, where the stability of the metastable tetragonal phase is relatively high and thus the tetragonal phase persists even at the liquid nitrogen temperature. On the other hand, the high temperature tetragonal phase of pure zirconia can never be quenched-in at room temperature by a rapid cooling; instead it always turns into monoclinic phase at room temperature. This suggests the occurrence of an athermal transformation after escaping the isothermal transformation, provided the cooling rate was fast enough to suppress the isothermal transformation. Thus, with an intermediate yttria composition, it would be possible to obtain the tetragonal phase which is not only metastable at room temperature but athermally transforms into the monoclinic phase by subzero cooling. The objective of the present work is to show that, with a certain range of yttria content, the tetragonal phase can be quenched in at room temperature and undergoes isothermal transformation and athermal transformation depending on being heated at a moderate temperature or under-cooled below room temper

关键词： Y2O3 ZrO2 等温马氏体相变变温马氏体相变

Rotation of Biological Cells:Fundamentals and Applications

在线全文

学校读者我要写书评

暂无评论

Engineering 2022年第3期8卷 110-126页

作者： Tao Tang Yoichiroh Hosokawa Takeshi hayakawa Yo Tanaka Weihua Li Ming Li Yaxiaer Yalikun Division of Materials Science Nara Institute of Science and TechnologyNara 630-0192Japan Institute of Innovation for Future Society Nagoya UniversityAichi 464-8603Japan Department of Precision Mechanics Faculty of Science and EngineeringChuo UniversityTokyo 112-8551Japan Graduate School of Frontier Biosciences Osaka UniversityOsaka 565-0871Japan RIKEN Center for Biosystems Dynamics Research Osaka 565-0871Japan School of Mechanical MaterialsMechatronicand Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia School of Engineering Macquarie UniversitySydneyNSW 2109Australia

Cell rotation is one of the most important techniques for cell manipulation in modern bioscience,as it not only permits cell observation from any arbitrary angle,but also simplifies the procedures for analyzing the mechanical properties of cells,characterizing cell physiology,and performing *** approaches have been reported for rotating cells in a wide range of academic and industrial *** them,the most popular are micro-robot-based direct contact manipulation and field-based non-contact methods(e.g.,optical,magnetic,electric,acoustic,and hydrodynamic methods).This review first summarizes the fundamental mechanisms,merits,and demerits of these six main groups of approaches,and then discusses their differences and limitations in *** aim to bridge the gap between each method and illustrate the development progress,current advances,and prospects in the field of cell rotation.

关键词： Cell rotation Cell reorientation Micromanipulation Microfluidics

Ensemble learning framework for landslide susceptibility mapping:Different basic classifier and ensemble strategy

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2023年第6期14卷 170-190页

作者： Taorui Zeng Liyang Wu Dario Peduto Thomas Glade Yuichi S.hayakawa Kunlong Yin Institute of Geological Survey China University of GeosciencesWuhan 430074China ENGAGE—Geomorphic Systems and Risk Research Department of Geography and Regional ResearchUniversity of Vienna1010 ViennaAustria Faculty of Engineering China University of GeosciencesWuhanChina Department of Civil Engineering University of Salerno84084 SalernoFiscianoItaly Faculty of Environmental Earth Science Hokkaido UniversityHokkaido 060-0810Japan

The application of ensemble learning models has been continuously improved in recent landslide susceptibility research,but most studies have no unified ensemble ***,few papers have discussed the applicability of the ensemble learning model in landslide susceptibility mapping at the township *** study aims at defining a robust ensemble framework that can become the benchmark method for future research dealing with the comparison of different ensemble *** this purpose,the present work focuses on three different basic classifiers:decision tree(DT),support vector machine(SVM),and multi-layer perceptron neural network model(MLPNN)and two homogeneous ensemble models such as random forest(RF)and extreme gradient boosting(XGBoost).The hierarchical construction of deep ensemble relied on two leading ensemble technologies(i.e.,homogeneous/heterogeneous model ensemble and bagging,boosting,stacking ensemble strategy)to provide a more accurate and effective spatial probability of landslide *** selected study area is Dazhou town,located in the Jurassic red-strata area in the Three Gorges Reservoir Area of China,which is a strategic economic area currently characterized by widespread landslide *** on a long-term field investigation,the inventory counting thirty-three slow-moving landslide polygons was *** results show that the ensemble models do not necessarily perform better;for instance,the Bagging based DT-SVM-MLPNNXGBoost model performed worse than the single XGBoost *** the eleven tested models,the Stacking based RF-XGBoost model,which is a homogeneous model based on bagging,boosting,and stacking ensemble,showed the highest capability of predicting the landslide-affected ***,the factor behaviors of DT,SVM,MLPNN,RF and XGBoost models reflected the characteristics of slow-moving landslides in the Three Gorges reservoir area,wherein unfavorable lithological conditions and intense human engineering activitie

关键词： Three Gorges Reservoir Area Landslide susceptibility mapping Ensemble learning framework Uncertainty research

Sunitinib-induced hyperammonemic encephalopathy in metastatic gastrointestinal stromal tumors:A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2023年第31期11卷 7629-7634页

作者： Takaoki hayakawa Shinsuke Funakoshi Yasuo Hamamoto Kenro Hirata Takanori Kanai Department of Internal Medicine Division of Gastroenterology and HepatologyKeio University School of MedicineShinjuku-ku 160-8582TokyoJapan Division of Medical Oncology Department of Internal MedicineTokyo Saiseikai Central HospitalMinato-ku 108-0073TokyoJapan Keio Cancer Center Keio University School of MedicineShinjuku-ku 160-8582TokyoJapan Department of Internal Medicine Keio University School of MedicineShinjuku-ku 160-8582TokyoJapan

BACKGROUND Sunitinib,a multi-targeted tyrosine kinase inhibitor(TKI),has been approved for the salvage treatment of gastrointestinal stromal tumors(GIST).Hyperammonemic encephalopathy is a rare but severe complication of sunitinib ***,we present the case of a 66-year-old male with metastatic GIST without underlying liver cirrhosis who developed sunitinib-induced hyperammonemic *** SUMMARY A 66-year-old male with metastatic GIST was admitted because of reduced *** was administered as the first-line systemic *** experienced repeated episodes of peritonitis due to tumor perforation,and surgery was *** disease was confirmed based on increased liver metastasis,and sunitinib was initiated as a salvage ***,23 d after the third course of sunitinib,he presented to the emergency room with an episode of altered consciousness and behavioral *** on the patient clinical history and examination findings,sunitinib-induced encephalopathy was *** was discontinued,and the patient was treated for *** patient had a normal level of consciousness four days later,and the serum ammonia level gradually *** further neurological symptoms were reported in subsequent *** TKI-induced hyperammonemic encephalopathy is potentially *** receiving TKIs experiencing adverse reactions should undergo systemic evaluation and prompt treatment.

关键词： Tyrosine protein kinase inhibitors Sunitinib malate Hyperammonemic encephalopathy Gastrointestinal stromal tumors Case report