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Bending of Timoshenko beam with effect of crack gap based on equivalent spring model

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Applied Mathematics and Mechanics(English Edition) 2016年第4期37卷 513-528页

作者： xiao YANG jin HUANG Yu OUYANG Department of Civil Engineering Shanghai University

Considering the effect of crack gap, the bending deformation of the Timoshenko beam with switching cracks is studied. To represent a crack with gap as a nonlinear unidirectional rotational spring, the equivalent flexural rigidity of the cracked beam is derived with the generalized Dirac delta function. A closed-form general solution is obtained for bending of a Timoshenko beam with an arbitrary number of switching cracks. Three examples of bending of the Timoshenko beam are presented. The influence of the beam＇s slenderness ratio, the crack＇s depth, and the external load on the crack state and bending performances of the cracked beam is analyzed. It is revealed that a cusp exists on the deflection curve, and a jump on the rotation angle curve occurs at a crack location. The relation between the beam＇s deflection and load is bilinear, each part corresponding to an open or closed state of crack, respectively. When the crack is open, flexibility of the cracked beam decreases with the increase of the beam＇s slenderness ratio and the decrease of the crack depth. The results are useful in identifying non-destructive cracks on a beam.

关键词： Timoshenko beam switching crack crack gap generalized function parameter study

Novel combinatorial algorithm for the problems of fuzzy grey multi-attribute group decision making

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Journal of Systems Engineering and Electronics 2007年第4期18卷 774-780页

作者： Rao Congjun xiao Xinping Peng jin Coll. of Mathematics and Information Science Huanggang Normal Univ. Huanggang 438000 P. R. China School of Science Wuhan Univ. of Technology Wuhan 430063 P. R. China

To study the fuzzy and grey information in the problems of multi-attribute group decision making, the basic concepts of both fuzzy grey numbers and grey interval numbers are given firstly, then a new model of fuzzy grey multi-attribute group decision making based on the theories of fuzzy mathematics and grey system is presented. Furthermore, the grey interval relative degree and deviation degree is defined, and both the optimistic algorithm of the grey interval relational degree and the algorithm of deviation degree minimization for solving this new model are also given. Finally, a decision making example to demonstrate the feasibility and rationality of this new method is given, and the results by using these two algorithms are uniform.

关键词： multi-attribute group decision making fuzzy grey number grey interval relational degree deviation degree

Oncogenic osteomalacia caused by a phosphaturic mesenchymal tumor of the femur: A case report

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World Journal of Clinical Cases 2019年第15期7卷 2081-2086页

作者： Dong Tang xiao-Man Wang Yong-Sheng Zhang xiao-xiao mi Department of Medical Imaging(Radiology) The Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310015Zhejiang ProvinceChina Department of Ultrasound The Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310015Zhejiang ProvinceChina Department of Radiology Hangzhou Hospital of Traditional MedicineHangzhou 310015Zhejiang ProvinceChina Department of Radiology The Second Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310015Zhejiang ProvinceChina Institute of Translational Medicine The Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310015Zhejiang ProvinceChina

BACKGROUND Oncogenic osteomalacia caused by phosphaturic mesenchymal tumors is very difficult to *** report a case of tumor-induced osteomalacia caused by a phosphaturic mesenchymal tumor of the left femur in a middle-aged woman after medical imaging and *** SUMMARY A 57-year-old woman presented with progressive bone pain for five *** was diagnosed with hypophosphatemic osteomalacia,as her laboratory data showed low serum phosphorus and low serum *** knee joint radiography revealed an osteolytic lesion of the left femur.A computed tomography scan showed mixed density shadows in the left *** resonance imaging of the left femur showed the presence of an oval area with a hypointense signal in T1-weighted magnetic resonance imaging(MRI)and highlow mixed signal in T2-weighted *** samples revealed the presence of short spindle cells,vascularization,and characteristics of phosphaturic mesenchymal *** resection was performed,and the clinical presentations and laboratory abnormalities were *** Diagnosis of oncogenic osteomalacia is difficult due to the varieties and localization of source tumors and absence of pathognomonic biomedical *** case highlights the importance of a combination of medical imaging and biopsy in the diagnosis of oncogenic osteomalacia caused by a phosphaturic mesenchymal tumor.

关键词： Oncogenic osteomalacia Phosphaturic mesenchymal tumor Hypophosphatemia Hypocalcemia Case report

MULTIPLICITY-PRESERVING TRIANGULAR SET DECOMPOSITION OF TWO POLYNOmiALS

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Journal of Systems Science & Complexity 2014年第6期27卷 1320-1344页

作者： CHENG jin-San GAO xiao-Shan Key Laboratory of Mathematics Mechanization Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of Sciences

In this paper, a multiplicity-preserving triangular set decomposition algorithm is proposed for a system of two polynomials, which involves only computing the primitive polynomial remainder sequence of two polynomials once and certain GCD computations. The algorithm decomposes the unmixed variety defined by two polynomials into square free and disjoint （for non-vertical components, see Definition 4） algebraic cycles represented by triangular sets which may have negative multiplicities. Thus, the authors can count the multiplicities of the non-vertical components. In the bivariate case, the amthors give a complete algorithm to decompose tile system into zeros represented by triangular sets with multiplicities. The authors also analyze the complexity of the algorithm in the bivariate ease. The authors implement the algorithm and show the effectiveness of the method with extensive experiments.

关键词： Algebraic cycle multiplicity-preserving primitive polynomial remainder sequence trian-gular set decomposition.

A Two-Stage Service Replica Strategy for Business Process Efficiency Optimization in Community Cloud

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Chinese Journal of Electronics 2017年第1期26卷 80-87页

作者： LUO Haoyu LIU jin LIU xiao State Key Laboratory of Software Engineering School of Computer Wuhan University School of Information Technology Deakin University

Business process that facilitates the organization cooperation and resource sharing plays an important role in Community cloud(Comc). The nature of applications and decentralized infrastructure in Comc make it a big challenge in ensuring the execution efficiency of business process, especially when the business requests are in high concurrency. We present a two-stage service replica strategy to improve the execution efficiency of business process by shortening the response time of request to single service and reducing interaction time among distributed services. We initially utilize the social network property of services to pre-allocate the replicas of key services. After that, queueing model is adopted to determine the required additional replicas according to the quantity and frequency of user requests, then schedule service replicas and requests dynamically. Experiments demonstrate the effectiveness of the proposed strategy.

关键词： Community cloud(Comc) Business process Execution efficiency Service replica Queueing theory

Violent Transient Sloshing-Wave Interaction with a Baffle in a Three-Dimensional Numerical Tank

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Journal of Ocean University of China 2017年第4期16卷 661-673页

作者： XUE mi-An ZHENG jinhai LIN Pengzhi xiao Zhong State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098P.R.China College of Harbour Coastal and Offshore Engineering Hohai UniversityNanjing 210098P.R.China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072P.R.China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065P.R.China

A finite difference model for solving Navier Stokes viscous liquid sloshing-wave interaction with baffles in a tank. equations with turbulence taken into accotmt is used to investigate The volume-of-fluid and virtual boundary force methods are employed to simulate free surface flow interaction with structures. A liquid sloshing experimental apparatus was established to evaluate the accuracy of the proposed model, as well as to study nonlinear sloshing in a prismatic tank with the baffles. Damping effects of sloshing in a rectangular tank with bottom-mounted vertical baffles and vertical baffles touching the free surface are studied numerically and experimentally. Good agreement is obtained between the present numerical results and experimental data. The numerical results match well with the current experimental data for strong nonlinear sloshing with large free surface slopes. The reduction in sloshing-wave elevation and impact pressure induced by the bottom-mounted vertical baffle and the vertical baffle touching the free surface is estimated by varying the external excitation frequency and the location and height of the vertical baffle under horizontal excitation.

关键词： transient sloshing wave vertical baffle excitation frequency experimental and numerical study

先天性心脏病儿童156例营养不良发生现状及影响因素分析

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安徽医药 2025年第1期29卷 83-86页

作者：肖瑾朱琳陈思陕西省森林工业职工医院儿童保健科陕西西安710300

目的探讨先天性心脏病儿童营养不良发生现状及影响因素。方法选取陕西省森林工业职工医院2019年6月至2022年7月收治的156例先天性心脏病病人,采用Z评分法评估病人的营养状况。根据病人营养状况将其分为营养不良组和正常组,比较两组病人... 详细信息

目的探讨先天性心脏病儿童营养不良发生现状及影响因素。方法选取陕西省森林工业职工医院2019年6月至2022年7月收治的156例先天性心脏病病人,采用Z评分法评估病人的营养状况。根据病人营养状况将其分为营养不良组和正常组,比较两组病人一般资料,采用多因素回归分析先天性心脏病病人营养不良的影响因素。结果156例先天性心脏病病人中营养不良发生率为58.97%,其中急性营养不良发生率为26.92%,慢性营养不良发生率为32.05%;营养不良组病情复杂占比(57.61%比34.37%)、家庭经济收入低占比(45.65%比21.88%)、母亲对疾病感知度不准确占比(57.61%比35.94%)、低出生体质量儿占比(38.04%比23.44%)、心脏增大占比(21.74%比9.37%)、治疗前有症状占比(73.91%比34.38%)、确诊时间≥1年占比(68.48%比29.69%)、住院次数>4次占比(33.70%比12.50%)、感染占比(70.65%比29.69%)及来自农村占比(63.04%比40.62%)均高于营养正常组(均P<0.05);logistic回归分析发现,病情复杂程度、家庭经济收入、出生体质量、确诊时间、住院次数及感染均是先天性心脏病病人发生营养不良的独立危险因素(P<0.05)。结论病情复杂程度、出生体质量、住院次数以及家庭来源均是先天性心脏病病人营养不良的独立危险因素。

关键词：先天性心脏病儿童营养不良营养状况影响因素

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Fabrication of low-resistance LaNi_xO_(3+δ) thin films for ferroelectric device electrodes

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Journal of Rare Earths 2018年第8期36卷 838-843页

作者： mi xiao Zebin Zhang Weikang Zhang Ping Zhang Kuibo Lan School of Electrical and Information Engineering & Key Laboratory of Advanced Ceramics and Machining Technology of ministry of Education Tianjin University

LaNiO3 thin films with different La/Ni ratios were deposited on Si substrates by sol-gel process. The electrical resistivities of LaNixO3＋δfilms with different La/Ni ratios were measured by four-probe ***（0.95）O3＋δthin film has the lowest resistivity. First-principle calculations show that LaNi（0.95）O3＋δhas the largest Ni-O-Ni bond angle and the shortest Ni-O bond length, which means LaNi（0.95）O3＋δhas the strongest metallic property, hence, the electrical resistivity is the lowest. Au/PZT（PbZr（0.52）Ti（0.48）O3）/LaNixO3＋δand Au/PZT/Pt ferroelectric capacitors were fabricated to evaluate LaNixO3＋δas a bottom electrode. It is shown that fatigue properties of PZT films can be significantly improved by using LaNixO3＋δinstead of Pt as the bottom electrode. The Ⅰ-Ⅴ test results of PZT films show that LaNi（0.95）O3＋δas bottom electrode can reduce the threshold voltages of PZT films, suggesting that La/Ni ratio in LaNixO3＋δas a large influence on the film properties.

关键词： LaNiO3 Thin film Sol-gel Electrical property First-principle calculation Rare earths

Construction of Protograph LDPC Codes Based on the Convolution Neural Network

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China Communications 2023年第5期20卷 84-92页

作者： Zhiyuan xiao Liguang Li jin Xu jin Sha School of Electronic Science and Engineering Nanjing UniversityNanjing 210023China Institute of Wireless Research ZTE CorporationShenzhen 518055China

This paper presents an intelligent protograph construction *** LDPC codes have shown excellent error correction performance and play an important role in wireless *** search or manual construction are often used to obtain a good protograph,but the efficiency is not high enough and many experience and skills are *** this paper,a fast searching algorithm is proposed using the convolution neural network to predict the iterative decoding thresholds of protograph LDPC codes effectively.A special input data transformation rule is applied to provide stronger generalization *** proposed algorithm converges faster than other *** iterative decoding threshold of the constructed protograph surpasses greedy algorithm and random search by about 0.53 dB and 0.93 dB respectively under 100 times of density *** results show that quasi-cyclic LDPC(QC-LDPC)codes constructed from the proposed algorithm have competitive performance compared to other papers.

关键词： LDPC codes protograph codes iterative decoding threshold neural network