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“二号自我”会使你获得最佳成就
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作者 凌苑 《青少年心理健康》 2003年第6期8-8,共1页
关键词 网球训练 “二号自我” 笛莫西·盖尔卫 《网球运动员的内心竞争》 分心法
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NUMERICAL SIMULATIONS OF EVOLUTIONS FROM WALL PULSE TO TURBULENT COHE RENT STRUCTURES
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作者 张立 唐登斌 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第1期17-22,共6页
The high order compact d if ference method is developed for solving the perturbation equations based on Navi er Stokes equations, and is used in studying complex evolution processes from w all negative pulse to the ... The high order compact d if ference method is developed for solving the perturbation equations based on Navi er Stokes equations, and is used in studying complex evolution processes from w all negative pulse to the turbulent coherent structure in the channel flow. Th is method contains three dimensional coupling difference scheme with high accur acy and high resolution, and the high order time splitting methods. Compared with the general spectral method, the method can be used to research turbule nt coherent structure under more general boundary conditions and in flow domains . In this paper, the generation and evolution of the turbulent coherent structur es ind uced by wall pulse in the channel flow are simulated, and the basic characterist ics and rules of the turbulent coherent structure are shown. Computational r esults indicate that a wall negative pulse is more convenient than the resonant three wave model. 展开更多
关键词 coherent structure TURBULENCE Navier Stokes equations three dimensional coupling difference sc heme high order time splitting method
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An Improved Genetic Algorithm for Allocation Optimization of Distribution Centers 被引量:7
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作者 钱晶 庞小红 吴智铭 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期73-76,共4页
This paper introduced an integrated allocation model for distribution centers (DCs). The facility cost, inventory cost, transportation cost and service quality were considered in the model. An improved genetic algorit... This paper introduced an integrated allocation model for distribution centers (DCs). The facility cost, inventory cost, transportation cost and service quality were considered in the model. An improved genetic algorithm (IGA) was proposed to solve the problem. The improvement of IGA is based on the idea of adjusting crossover probability and mutation probability. The IGA is supplied by heuristic rules too. The simulation results show that the IGA is better than the standard GA(SGA) in search efficiency and equality. 展开更多
关键词 distribution center allocation optimization improved genetic algorithm
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Prediction of central bursting defects in rod extrusion process with upper bound analysis method 被引量:2
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作者 Amir PARGHAZEH Heshmatollah HAGHIGHAT 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期2892-2899,共8页
The prediction of central bursting defects in the rod extrusion process through conical dies using the upper bound analysisis investigated. A kinematically admissible velocity field, including the radial and angular v... The prediction of central bursting defects in the rod extrusion process through conical dies using the upper bound analysisis investigated. A kinematically admissible velocity field, including the radial and angular velocity components, is proposed. A newcriterion is presented to predict the occurrence of the central bursting defects. Parameter bobt, which represents the risk probability ofcracking, is proposed. It is calculated using the shape of the boundary at the entrance by minimizing the total power dissipationduring the extrusion process. When bobt is equal to or greater than bcr, central bursting occurs. Furthermore, the quantitativerelationships between central bursting defects and process parameters (semi die angle, reduction in area and frictional factor) arestudied. The results show that the central bursting defects are affected primarily by the reduction in area and the friction factor. Thepresented criterion is verified by comparing with the FEM simulation data and the results of the published paper. 展开更多
关键词 central bursting defect upper bound analysis method rod extrusion process
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Cardiovascular co-morbidity in chronic kidney disease:Current knowledge and future research needs 被引量:9
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作者 Hudaifa Alani Asad Tamimi Nihad Tamimi 《World Journal of Nephrology》 2014年第4期156-168,共13页
Chronic kidney disease(CKD) is recognised as a health concern globally and leads to high rates of morbidity,mortality and healthcare expenditure.CKD is itself an independent risk factor for unfavorable health outcomes... Chronic kidney disease(CKD) is recognised as a health concern globally and leads to high rates of morbidity,mortality and healthcare expenditure.CKD is itself an independent risk factor for unfavorable health outcomes that include cardiovascular disease(CVD).Coronary artery disease is the primary type of CVD in CKD patients and a significant cause of death among renal transplant patients.Traditional and non-traditional risk factors for CVD exist in patients with CKD.Traditional factors include smoking,hypertension,dyslipidemia and diabetes which are highly prevalent in CKD patients.Non-traditional risk factors of CKD are mainly uraemiaspecific and increase in prevalence as kidney function declines.Some examples of uraemia-specific risk factors that have been well documented include low levels of haemoglobin,albuminuria,and abnormal bone and mineral metabolism.Therapeutic interventions targeted at more traditional risk factors which contribute to CVD,have not had the desired effect on lowering CVD events and mortality in those suffering with CKD.Future research is warranted to delineate clear evidence to the benefit of modifying non-traditional risk factors. 展开更多
关键词 Cardiovascular disease Chronic kidney disease Risk factors INFLAMMATION
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Power Spectral Analysis of Heart Rate Variability of Driver Fatigue 被引量:2
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作者 焦昆 李增勇 +1 位作者 陈铭 王成焘 《Journal of Donghua University(English Edition)》 EI CAS 2005年第1期11-15,共5页
This investigation was to evaluate the driving fatigue based on power spectral analysis of heart rate variability (HRV) under vertical vibration. Forty healthy male subjects (29.7±3.5 years) were randomly divided... This investigation was to evaluate the driving fatigue based on power spectral analysis of heart rate variability (HRV) under vertical vibration. Forty healthy male subjects (29.7±3.5 years) were randomly divided into two groups, Group A (28.8±4.3 years) and Group B (30.6±2.7 years). Group A (experiment group) was required to perform the simulated driving and Group B (control group) kept calm for 90 min. The frequency domain indices of HRV such as low frequency (0.04 0.15 Hz, LF), high frequency (0.150.4 Hz, HF), LF/HF together with the indices of hemodynamics such as blood pressure (BP) and heart rate (HR) of the subjects between both groups were calculated and analyzed after the simulated driving. There were significances of the former indices between both groups (P<0.05). All the data collected after experiment of Group A was observed the remarkable linear correlation (P<0.05) and parameters and errors of their linear regression equation were stated (α=0.05, P<0.001) in this paper, respectively. The present study investigated that sympathetic activity of the subjects enhanced after the simulated driving while parasympathetic activities decreased. The sympathovagal balance was also improved. As autonomic function indictors of HRV reflected fatigue level, quantitative evaluation of driving mental fatigue from physiological reaction could be possible. 展开更多
关键词 driving fatigue heart rate variability blood pressure heart rate VIBRATION correlation.
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Podocyturia: Potential applications and current limitations 被引量:2
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作者 Hernán Trimarchi 《World Journal of Nephrology》 2017年第5期221-228,共8页
Chronic kidney disease is a prevalent condition that affects millions of people worldwide and is a major risk factor of cardiovascular morbidity and mortality. The main diseases that lead to chronic kidney disease are... Chronic kidney disease is a prevalent condition that affects millions of people worldwide and is a major risk factor of cardiovascular morbidity and mortality. The main diseases that lead to chronic kidney disease are frequent entities as diabetes mellitus, hypertension and glomerulopathies. One of the clinical markers of kidney disease progression is proteinuria. Moreover, the histological hallmark of kidney disease is sclerosis, located both in the glomerular and in the interstitial compartments. Glomerulosclerosis underscores an irreversible lesion that is clinically accompanied by proteinuria. In this regard, proteinuria and glomerular sclerosis are linked by the cell that has been conserved phylogenetically not only to prevent the loss of proteins in the urine, but also to maintain the health of the glomerular fltration barrier: The podocyte. It can then be concluded that the link between proteinuria, kidney disease progression and chronic kidney disease is mainly related to the podocyte. What is this situation due to? The podocyte is unable to proliferate under normal conditions, and a complex molecular machinery exists to avoid its detachment and eventual loss. When the loss of podocytes in the urine, or podocyturia, is taking place and its glomerular absolute number decreased, glomerulosclerosis is the predominant histological feature in a kidney biopsy. Therefore, tissular podocyte shortage is the cause of proteinuria and chronic kidney disease. In this regard, podocyturia has been demonstrated to precede proteinuria, showing that the clinical mana-gement of proteinuria cannot be considered an early intervention. The identifcation of urinary podocytes could be an additional tool to be considered by nephrologists to assess the activity of glomerulopathies, for follow-up purposes and also to unravel the pathophysiology of podocyte detachment in order to tailor the therapy of glomerular diseases more appropriately. 展开更多
关键词 PODOCYTE Podocyturia GLOMERULOPATHY Chronic kidney disease PROTEINURIA
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Baroreflex dysfunction in chronic kidney disease 被引量:2
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作者 Manpreet Kaur Dinu S Chandran +3 位作者 Ashok Kumar Jaryal Dipankar Bhowmik Sanjay Kumar Agarwal Kishore Kumar Deepak 《World Journal of Nephrology》 2016年第1期53-65,共13页
Chronic kidney disease (CKD) patients have high cardiovascular mortality and morbidity. The presence of traditional and CKD related risk factors results in exaggerated vascular calcification in these patients. Vascu... Chronic kidney disease (CKD) patients have high cardiovascular mortality and morbidity. The presence of traditional and CKD related risk factors results in exaggerated vascular calcification in these patients. Vascular calcification is associated with reduced large arterial compliance and thus impaired barorefex sensi-tivity (BRS) resulting in augmented blood pressure (BP) variability and hampered BP regulation. Barorefex plays a vital role in short term regulation of BP. This review discusses the normal barorefex physiology, methods to assess baroreflex function, its determinants along with the prognostic significance of assessing BRS in CKD patients, available literature on BRS in CKD patients and the probable patho-physiology of barorefex dysfunction in CKD. 展开更多
关键词 Large arterial compliance Chronic kidney disease Vascular calcification Baroreflex sensitivity Blood pressure variability
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Arterial stiffness, vascular calcification and bone metabolism in chronic kidney disease 被引量:1
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作者 János Nemcsik István Kiss András Tislér 《World Journal of Nephrology》 2012年第1期25-34,共10页
Patients with chronic kidney disease (CKD) have an extremely poor cardiovascular outcome. Arterial stiff-ness, a strong independent predictor of survival in CKD, is connected to arterial media calcification. A huge ... Patients with chronic kidney disease (CKD) have an extremely poor cardiovascular outcome. Arterial stiff-ness, a strong independent predictor of survival in CKD, is connected to arterial media calcification. A huge number of different factors contribute to the increased arterial calcification and stiffening in CKD, a process which is in parallel with impaired bone metabolism. This coincidence was demonstrated to be part of the direct inhibition of calcifcation in the vessels, which is a counterbalancing effect but also leads to low bone turnover. Due to the growing evidence, the defnition of “CKD mineral bone disorder” was created recently, un-derlining the strong connection of the two phenomena. In this review, we aim to demonstrate the mechanisms leading to increased arterial stiffness and the up-to date data of the bone-vascular axis in CKD. We over-view a list of the different factors, including inhibitors of bone metabolism like osteoprotegerin, fetuin-A, pyro-phosphates, matrix Gla protein, osteopontin, fbroblast growth factor 23 and bone morphogenic protein, which seem to play role in the progression of vascular calcif-cation and we evaluate their connection to impaired ar-terial stiffness in the mirror of recent scientifc results. 展开更多
关键词 Arterial stiffness Vascular calcification Bone metabolism Chronic kidney disease
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Arsenic exposure decreases rhythmic contractions of vascular tone through sodium transporters and K^+ channels
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作者 Javier Palacios Chukwuemeka R Nwokocha Fredi Cifuentes 《World Journal of Pharmacology》 2014年第2期18-23,共6页
Arsenic-contaminated drinking water is a public health problem in countries such as Taiwan, Bangladesh, United States, Mexico, Argentina, and Chile. The chronic ingestion of arsenic-contaminated drinking water increas... Arsenic-contaminated drinking water is a public health problem in countries such as Taiwan, Bangladesh, United States, Mexico, Argentina, and Chile. The chronic ingestion of arsenic-contaminated drinking water increases the risk for ischemic heart disease, cerebrovascular disease, and prevalence of hypertension. Although toxic arsenic effects are controversial, there is evidence that a high concentration of arsenic may induce hypertension through increase in vascular tone and resistance. Vascular tone is regulated by the rhythmic contractions of the blood vessels, generated by calcium oscillations in the cytosol of vascular smooth muscle cells. To regulate the cytosolic calcium oscillations, the membrane oscillator model involves the participation of Ca2+ channels, calcium-activated K+ channels, Na+/Ca2+exchange, plasma membrane Ca2+-ATPase, and the Na+/K+-ATPase. However, little is known about the role of K+ uptake by sodium transporters [Na+/K+-ATPase or Na+-K+-2Cl-(NKCC1)] on the rhythmic contractions.Vascular rhythmic contractions, or vasomotion are a local mechanism to regulate vascular resistance andblood flow. Since vascular rhythmic contractions of blood vessels are involved in modulating the vascular resistance, the blood flow, and the systemic pressure,we suggest a model explaining the participation of the sodium pump and NKCC1 co-transporter in low dose arsenic exposure effects on vasomotion and vascular dysfunction. 展开更多
关键词 Arsenic VASOMOTION Na^+/K^+-ATPase Na^+-K^+-2Cl^- K^+ channels Nitric oxide PROSTAGLANDIN Vascular
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Evaluation of mixed-mode stress intensity factors by extended finite element method 被引量:3
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作者 茹忠亮 赵洪波 尹顺德 《Journal of Central South University》 SCIE EI CAS 2013年第5期1420-1425,共6页
Extended finite element method (XFEM) implementation of the interaction integral methodology for evaluating the stress intensity factors (SIF) of the mixed-mode crack problem is presented. A discontinuous function... Extended finite element method (XFEM) implementation of the interaction integral methodology for evaluating the stress intensity factors (SIF) of the mixed-mode crack problem is presented. A discontinuous function and the near-tip asymptotic function are added to the classic finite element approximation to model the crack behavior. Two-state integral by the superposition of actual and auxiliary fields is derived to calculate the SIFs. Applications of the proposed technique to the inclined centre crack plate with inclined angle from 0° to 90° and slant edge crack plate with slant angle 45°, 67.5° and 90° are presented, and comparisons are made with closed form solutions. The results show that the proposed method is convenient, accurate and computationallv efficient. 展开更多
关键词 stress intensity factor (SIF) interaction integral method extended finite element method (XFEM)
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Numerical and experimental analyses for bearing capacity of rigid strip footing subjected to eccentric load 被引量:1
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作者 卢谅 王宗建 K.ARAI 《Journal of Central South University》 SCIE EI CAS 2014年第10期3983-3992,共10页
A footing may get an eccentric load caused by earthquake or wind, thus the bearing capacity of footing subjected to eccentric load become a fundamental geotechnical problem. The conventional limit equilibrium method u... A footing may get an eccentric load caused by earthquake or wind, thus the bearing capacity of footing subjected to eccentric load become a fundamental geotechnical problem. The conventional limit equilibrium method used for this problem usually evaluates the material properties only by its final strength. But the classical finite element method(FEM) does not necessarily provide a clear collapse mechanism associated with the yield condition of elements. To overcome these defects, a numerical procedure is proposed to create an explicit collapse mode combining a modified smeared shear band approach with a modified initial stress method. To understand the practical performance of sand foundation and verify the performance of the proposed procedure applied to the practical problems, the computing results were compared with the laboratory model tests results and some conventional solutions. Furthermore, because the proposed numerical procedure employs a simple elasto-plastic model which requires a small number of soil parameters, it may be applied directly to practical design works. 展开更多
关键词 bearing capacity eccentric load slip surface shear band finite element method model test
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Impact of renal transplantation on cardiac morphological and functional characteristics in children and adults
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作者 Sahier Omar El-Khashab Eman El-Sayed Mohamed +2 位作者 Mahmoud A Soliman Hussein Heshmat Kassem Amin Roshdy Soliman 《World Journal of Nephrology》 2016年第6期517-523,共7页
AIM To compare the effects of renal transplantation on cardiac functions in children and adults.METHODS One hundred and ten patients attending the nephrology outpatient clinic were enrolled in this study and were divi... AIM To compare the effects of renal transplantation on cardiac functions in children and adults.METHODS One hundred and ten patients attending the nephrology outpatient clinic were enrolled in this study and were divided into six groups. The first two groups consisted each of 30 renal transplant patients who had a successful renal transplantation more than six months, but less than one year. Group Ⅰ were less than 18 years and group Ⅱ were more than 18 years. The third and fourth groups, each were 20 chronic renal failure patients on regular hemodialysis. Again, group Ⅲ were less than 18 years and group Ⅳ were more than 18 years. Group Ⅴ and Ⅵ(The control Groups) consisted each of 5 subjects below and above 18 years of age, respectively with normal kidney functions. All patients were subjected to history and examination. The kidney functions and the hemoglobin were analyzed. Afterobtaining informed consent, echocardiography was done to all patients.RESULTS There was a statistically significant improvement(P < 0.0001) in all cardiac parameters. A regression in left ventricular end diastolic volume(LVED) both in children(4.7 ± 0.8 to 4.2 ± 0.5) and in adults(5.9 ± 0.7 to 4.9 ± 0.6) were found. There was a regression in left ventricular end systolic volume(LVES) both in children(3.1 ± 0.6 to 2.4 ± 0.4) and in adults(4.1 ± 0.9 to 3.1 ± 0.5). Fractional shortening improves both in children(32.6 ± 5.3 to 41.7 ± 7.6) and in adults(29.0 ± 6.6 to 36.5 ± 4.1). The improvement in ejection fraction(EF) was higher in children(59.7 ± 7.0 to 71.9 ± 6.1) than in adults(52.0 ± 12.5 to 64.8 ± 5.9). However, this degree of improvement(in children: 12.2 ± 5.1) did not show statistical difference(P-value 0.8), when compared to adults(12.7 ± 9.8). CONCLUSION After renal transplantation cardiac functions and morphology(EF/LVED/LVES) do improve markedly and rapidly in both children and adults. 展开更多
关键词 Echocardiography chronic renal disease Renal transplantation Cardiac problems
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Heuristic Virtual Machine Allocation for Multi-Tier Ambient Assisted Living Applications in a Cloud Data Center
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作者 Jing Bi Haitao Yuan +1 位作者 Ming Tie Xiao Song 《China Communications》 SCIE CSCD 2016年第5期56-65,共10页
Cloud computing provides the essential infrastructure for multi-tier Ambient Assisted Living(AAL) applications that facilitate people's lives. Resource provisioning is a critically important problem for AAL applic... Cloud computing provides the essential infrastructure for multi-tier Ambient Assisted Living(AAL) applications that facilitate people's lives. Resource provisioning is a critically important problem for AAL applications in cloud data centers(CDCs). This paper focuses on modeling and analysis of multi-tier AAL applications, and aims to optimize resource provisioning while meeting requests' response time constraint. This paper models a multi-tier AAL application as a hybrid multi-tier queueing model consisting of an M/M/c queueing model and multiple M/M/1 queueing models. Then, virtual machine(VM) allocation is formulated as a constrained optimization problem in a CDC, and is further solved with the proposed heuristic VM allocation algorithm(HVMA). The results demonstrate that the proposed model and algorithm can effectively achieve dynamic resource provisioning while meeting the performance constraint. 展开更多
关键词 ambient assisted living cloud computing resource provisioning virtual machine heuristic optimization
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Clinical observation of Huatan Huoxue Formula in treating coronary heart disease with hyperlipidemia
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作者 Dong Qiaozhi Lin Qian +3 位作者 Zhang Liyuan Wang Yu'nong Wang Yao Cai Lingling 《World Journal of Integrated Traditional and Western Medicine》 2016年第4期13-15,共3页
OBJECTIVE: To explore the effect of the Huatan Huoxue Formula combined with atorvastatin calcium in the treatment of coronary heart disease with hyperlipidemia. METHODS: 50 patients with coronary heart disease and hyp... OBJECTIVE: To explore the effect of the Huatan Huoxue Formula combined with atorvastatin calcium in the treatment of coronary heart disease with hyperlipidemia. METHODS: 50 patients with coronary heart disease and hyperlipidemia were randomly divided into the experimental group and the control group, with 25 cases in each group, who were treated in the East Hospital of Beijing University of Chinese Medicine. From March 2015 to April 2016. Patients in the experimental group were given the Huatan Huoxue Formula combined with atorvastatin with 8 weeks; while the control group was just treated with atorvastatin. Blood Lipid changes were compared between the two groups. RESULTS: Blood Lipid levels were significantly improved in the two groups after treatment. Compared with the control group, the levels of TG, TC and LDL-C in the experimental group were decreased, while the HDL-C was increased more significantly. The difference was statistically significant(P<0.05).CONCLUSIONS: The effect of the Huatan Huoxue Formula combined with atorvastatin on coronary heart disease and hyperlipidemia patients is more significant. 展开更多
关键词 Coronary heart disease HYPERLIPIDEMIA ATORVASTATIN Clinical effects
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Managing and Measuring Business Networks in Russia
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作者 Seppo E. Niittymaki Lauri J. Tenhunen 《Chinese Business Review》 2012年第5期483-490,共8页
The research topic of this article "Managing and measuring business networks in Russia" has been under consideration in three successive research projects oriented to Russian business to business (B2B) networks. T... The research topic of this article "Managing and measuring business networks in Russia" has been under consideration in three successive research projects oriented to Russian business to business (B2B) networks. The projects have been accomplished by HAMK, VTT Technical Research Centre of Finland, and Tampere University of Technology (TUT). Russian experts from The Higher School of Economics in Moscow and the Graduate School of Management in St. Petersburg were involved in these projects. We asked how managing and measuring B2B networks should be developed, when a company becomes established to Russian market. Both qualitative and quantitative analytical methods were used. Results concerning performance measurement presented in this article are based on data which was collected using survey and a questionnaire. Methodical triangulation was carried out as both research instruments produced 17 full answers for questions concerning performance measurement. Wider results are based on about 200 face-to-face interviews and answers for questionnaires. Results indicate that in Russia the management and leadership models as well as the company performance measurement should be adjusted to Russian traditions. Networked companies have difficulties in applying matrix type organizations in Russia, as management practices are based traditionally on authoritarian leadership. However, clear and specific targets should be set for projects and strategic business areas. Targets and bonuses should be agreed on with managers and staff throughout the company and the business network. Personal networks, within project stake- holders, have more emphasis in Russia than in Finland, because personal relations to authorities', and organizations are needed at every stage of the project. Therefore, managing SMEs working in B2B networks is challenging in Russia. In this article, a method for setting and implementing strategic targets for a business networked company is presented. Understanding networked performance measurement indicators will enable successful business for all networked partners in the long tenn. 展开更多
关键词 MANAGING measuring performance business networks RUSSIA
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Towards Efficient Security Policy Lookup on ManyCore Network Processing Platforms 被引量:1
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作者 WANG Xiang QI Yaxuan +2 位作者 WANG Kai XUE Yibo LI Jun 《China Communications》 SCIE CSCD 2015年第8期146-160,共15页
Modem network security devices employ packet classification and pattern matching algorithms to inspect packets. Due to the complexity and heterogeneity of different search data structures, it is difficult for existing... Modem network security devices employ packet classification and pattern matching algorithms to inspect packets. Due to the complexity and heterogeneity of different search data structures, it is difficult for existing algorithms to leverage modern hardware platforms to achieve high performance. This paper presents a Structural Compression (SC) method that optimizes the data structures of both algorithms. It reviews both algorithms under the model of search space decomposition, and homogenizes their search data structures. This approach not only guarantees deterministic lookup speed but also optimizes the data structure for efficient implementation oi1 many-core platforms. The performance evaluation reveals that the homogeneous data structure achieves 10Gbps line-rate 64byte packet classification throughput and multi-Gbps deep inspection speed. 展开更多
关键词 packet classification patternmatching ALGORITHMS data structures
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Tangential stress analysis of myocardial wall by finite element method
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作者 Guan Qiu Jiang Cao +2 位作者 Wang Xiaoyan Chen Shengyong Guan Fang 《Engineering Sciences》 EI 2011年第1期84-89,共6页
A novel method is presented to build the triangular surface model and calculate the tangential stress and strain of myocardial wall ,which can be further used to reflect the left ventricle twisting—a sensitive index ... A novel method is presented to build the triangular surface model and calculate the tangential stress and strain of myocardial wall ,which can be further used to reflect the left ventricle twisting—a sensitive index to assess the systolic and diastolic function of heart. Firstly, a point distribution model is used to obtain the feature points of the ventricular surface in medical images. Secondly, the surface model is constructed by triangular mesh, and then the subdivision strategy is introduced to refine the model. Thirdly, plane projection and finite element method(FEM) are applied to calculate the tangential stress and strain.Finally, the distribution of tangential modulus of elasticity is discussed. The stimulation results show that the proposed method can be used to compute the tangential stress and strain of myocardial wall effectively and the computing result is consistent with the results mentioned in the literatures. 展开更多
关键词 FEM stress and strain of myocardial wall tangential modulus of elasticity SUBDIVISION
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Bone Marrow Mononuclear Cell Extraction. Does the Operator Performance Affect Processing Efficacy?
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作者 Jakobsons Eriks Cakstina Inese +9 位作者 Erglis Kristaps Erglis Martins Pirtniece Liene Elina Krumina NarbuteInga Briede Ieva Jegere Sanda Smolova Rita Muiznieks Indrikis Erglis Andrejs 《Journal of Pharmacy and Pharmacology》 2016年第5期192-198,共7页
Different cell populations from bone marrow are used in various clinical trials for cardiac diseases during last decade. Four clinical studies are on going in our institution and enrol patients with cardiac diseases, ... Different cell populations from bone marrow are used in various clinical trials for cardiac diseases during last decade. Four clinical studies are on going in our institution and enrol patients with cardiac diseases, coronary disease and type 2 diabetes, patients with osteoarthritis. Density gradient is used to separate bone marrow mononuclear cells. Cell processing looses are significant. To find out critical control points we analysed processing process and differences in cell yields between operators performing cell extraction. Bone marrow mononuclear cells were isolated using Ficoll density gradient centrifugation. Cells were counted using flow cytometry for mononuclear cell total counts, CD34+ population count and viability analysis. The patients who underwent bone marrow aspiration followed by cell isolation received cell suspension for transplantation. Two cells processing for separate patients were performed at once. Same standard operation procedures were applied. Processing looses between operators performing cell extraction were analysed. Bone marrow samples from eight patients were processed. Mononuclear cells were extracted. Operator performances were compared. Operator A average bone marrow mononuclear cell yield in starting material was 9,97 ± 9,98 %, CD34+ population yield 75,46±79,67%. Operator B average bone marrow mononuclear cell yield in starting material was 24,68 ± 14,8 %, CD34+ population yield 70,42 ±44.84%. Operator A average cell viability in starting material was 45,24 ± 9,55%, after cell processing 42,96 ± 23,66 %. Operator B average cell viability in starting material was 49,85 ± 5,48%, after cell processing 69,52 ± 6,65 %. 展开更多
关键词 Bone marrow mononuclear cells cell yield cell extraction cell count
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The Research of Fractal Characteristics of the Electrocardiogram in a Real Time Mode
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作者 Valery Antonov Anatoly Kovalenko +1 位作者 Artem Zagaynov Vu Van Quang 《Journal of Mathematics and System Science》 2012年第3期191-195,共5页
The article presents the results of recent investigations into Holter monitoring of ECG, using non-linear analysis methods. This paper discusses one of the modern methods of time series analysis--a method of determini... The article presents the results of recent investigations into Holter monitoring of ECG, using non-linear analysis methods. This paper discusses one of the modern methods of time series analysis--a method of deterministic chaos theory. It involves the transition from study of the characteristics of the signal to the investigation of metric (and probabilistic) properties of the reconstructed attractor of the signal. It is shown that one of the most precise characteristics of the functional state of biological systems is the dynamical trend of correlation dimension and entropy of the reconstructed attractor. On the basis of this it is suggested that a complex programming apparatus be created for calculating these characteristics on line. A similar programming product is being created now with the support of RFBR. The first results of the working program, its adjustment, and further development, are also considered in the article. 展开更多
关键词 Holter monitoring ECG correlation dimension fractal analysis of time series non-linear dynamics of heart rate
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