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Gestational diabetes mellitus:The optimal time of delivery
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作者 Xuan Li Teng-Teng Li +4 位作者 Rui-Xian Tian Jia-Jia Fei Xing-Xing Wang Hui-Hui Yu Zong-Zhi Yin 《World Journal of Diabetes》 SCIE 2023年第3期179-187,共9页
Gestational diabetes mellitus(GDM)is a common pregnancy complication strongly associated with poor maternal-fetal outcomes.Its incidence and prevalence have been increasing in recent years.Women with GDM typically giv... Gestational diabetes mellitus(GDM)is a common pregnancy complication strongly associated with poor maternal-fetal outcomes.Its incidence and prevalence have been increasing in recent years.Women with GDM typically give birth through either vaginal delivery or cesarean section,and the maternal-fetal outcomes are related to several factors such as cervical level,fetal lung maturity,the level of glycemic control still present,and the mode of treatment for the condition.We categorized women with GDM based on the latter two factors.GDM that is managed without medication when it is responsive to nutrition-and exercise-based therapy is considered diet-and exercise-controlled GDM,or class A1 GDM,and GDM managed with medication to achieve adequate glycemic control is considered class A2 GDM.The remaining cases in which neither medical nor nutritional treatment can control glucose levels or patients who do not control their blood sugar are categorized as class A3 GDM.We investigated the optimal time of delivery for women with GDM according to the classification of the condition.This review aimed to address the benefits and harms of giving birth at different weeks of gestation for women with different classes of GDM and attempted to provide an analytical framework and clearer advice on the optimal time for labor. 展开更多
关键词 DIABETES GLUCOSE PREGNANCY Delivery optimal time Maternal-fetal outcomes
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Optimal time point for the transplantation of neural stem cells induced to differentiate with retinoic acid
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作者 Shuxin Wang Dengji Pan Na Liu Yongming Liu Juan Chen Houjie Ni Zhouping Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第16期1243-1247,共5页
Previous studies have demonstrated that differentiated neural stem cells (NSCs) are more suitable for transplantation than non-differentiated NSCs. In this study, NSCs were expanded in vitro for two passages, induce... Previous studies have demonstrated that differentiated neural stem cells (NSCs) are more suitable for transplantation than non-differentiated NSCs. In this study, NSCs were expanded in vitro for two passages, induced with retinoic acid to differentiate, and harvested between 1 6 days later. They were subsequently cultured in artificial cerebrospinal fluid for an additional 3 days, dudng which their growth and morphology was monitored. NSCs induced for 4 days exhibited a peak rate of cells differentiating into neurons and robust growth. Our results indicate that the optimal time point for transplanting NSCs is following a 4-day period of induced differentiation. 展开更多
关键词 neural stem cells retinoic acid artificial cerebrospinal fluid induced differentiation cell transplantation optimal time point neural regeneration
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Optimal timing for plastic surgical procedures for common congenital anomalies:A review
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作者 Aakanksha Goel Arun Goel 《World Journal of Clinical Pediatrics》 2024年第2期38-61,共24页
Apart from listening to the cry of a healthy newborn,it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents.The global incidence of children... Apart from listening to the cry of a healthy newborn,it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents.The global incidence of children born with congenital anomalies has been reported to be 3%-6%with more than 90%of these occurring in low-and middle-income group countries.The exact percentages/total numbers of children requiring surgical treatment cannot be estimated for several reasons.These children are operated under several surgical disciplines,viz,paediatric-,plastic reconstructive,neuro-,cardiothoracic-,orthopaedic surgery etc.These conditions may be life-threatening,e.g.,trachea-oesophageal fistula,critical pulmonary stenosis,etc.and require immediate surgical intervention.Some,e.g.,hydrocephalus,may need intervention as soon as the patient is fit for surgery.Some,e.g.,patent ductus arteriosus need‘wait and watch’policy up to a certain age in the hope of spontaneous recovery.Another extremely important category is that of patients where the operative intervention is done based on their age.Almost all the congenital anomalies coming under care of a plastic surgeon are operated as elective surgery(many as multiple stages of correction)at appropriate ages.There are advantages and disadvantages of intervention at different ages.In this article,we present a review of optimal timings,along with reasoning,for surgery of many of the common congenital anomalies which are treated by plastic surgeons.Obstetricians,paediatricians and general practitioners/family physicians,who most often are the first ones to come across such children,must know to guide the parents appropriately and convincingly impress upon the them as to why their child should not be operated immediately and also the consequences of too soon or too late. 展开更多
关键词 Plastic surgery Congenital anomalies Pediatric plastic surgery Facial cleft MICROTIA Vascular anomalies SYNDACTYLY HYPOSPADIAS optimal timing Pediatric surgery
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Harmonic balance-based approach for optimal time delay to control unstable periodic orbits of chaotic systems 被引量:3
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作者 Y.M.Chen Q.X.Liu J.K.Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2020年第4期918-925,共8页
As a classical technique for chaos suppression,the time-delayed feedback controlling strategy has been widely developed by stabilizing unstable periodic orbits(UPOs)embedded in chaotic systems.A critical issue for ach... As a classical technique for chaos suppression,the time-delayed feedback controlling strategy has been widely developed by stabilizing unstable periodic orbits(UPOs)embedded in chaotic systems.A critical issue for achieving high controlling precision is to search for an appropriate time delay.This paper proposes a simple yet effective approach,based on incremental harmonic balance method,to determine the optimal time delay in the delayed feedback controller.The time delay is adjusted within the iterative scheme provided by the proposed method,and finally converges to the period of the target UPO.As long as the optimal time delay is fixed,moreover,the attained solution makes it quite convenient to analyze its stability according to the Floquet theory,which further provides the effective interval of the feedback gain. 展开更多
关键词 Chaos control Unstable periodic orbit Delayed feedback optimal time delay Incremental harmonic balance method
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Optimal Time Decay of Navier–Stokes Equations with Low Regularity Initial Data
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作者 Jun Xiong JIA 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2018年第5期855-872,共18页
In this paper, we study the optimal time decay rate of isentropic Navier-Stokes equations under the low regularity assumptions about initial data. In the previous works about optimal time decay rate, the initial data ... In this paper, we study the optimal time decay rate of isentropic Navier-Stokes equations under the low regularity assumptions about initial data. In the previous works about optimal time decay rate, the initial data need to be small in H^[N/2]+2(R^N). Our work combined negative Besov space estimates and the conventional energy estimates in Besov space framework which is developed by Danchim Through our methods, we can get optimal time decay rate with initial data just small in B^N/2-1,N/2+1∩^N/2-1,N/2 and belong to some negative Besov space (need not to be small). Finally, combining the recent results in [25] with our methods, we only need the initial data to be small in homogeneous Besov space B^N/2-2,N/2 ∩B^N/2-1 to get the optimal time decay rate in space L2. 展开更多
关键词 Compressible fluids besov space framework optimal time decay negative Besov space
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Optimal time-decay rates of the Boltzmann equation
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作者 ZHONG MingYing 《Science China Mathematics》 SCIE 2014年第4期807-822,共16页
We consider the optimal time-convergence rates of the global solution to the Cauchy problem for the Boltzmann equation in R3.We show that the global solution tends to the global Maxwellian at the optimal time-decay ra... We consider the optimal time-convergence rates of the global solution to the Cauchy problem for the Boltzmann equation in R3.We show that the global solution tends to the global Maxwellian at the optimal time-decay rate(1+t)-3/4,where the macroscopic density,momentum and energy decay at the optimal rate(1+t)-3/4 and the microscopic part decays at the optimal rate(1+t)-5/4.We also show that the solution tends to the Maxwellian at the optimal time-decay rate(1+t).5/4 in the case of the macroscopic part of the initial data is zero,where the macroscopic density,momentum and energy decay at the optimal rate(1+t)-5/4 and the microscopic part decays at the optimal rate(1+t)-7/4.These convergence rates are shown to be optimal for the Boltzmann equation. 展开更多
关键词 Boltzmann equation optimal time decay rate
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Nitrogen and phosphorus changes and optimal drainage time of flooded paddy field based on environmental factors 被引量:4
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作者 Meng-hua XIAO Shuang-en YU +1 位作者 Yan-yan WANG Rong HUANG 《Water Science and Engineering》 EI CAS CSCD 2013年第2期164-177,共14页
While many controlled irrigation and drainage techniques have been adopted in China, the environmental effects of these techniques require further investigation. This study was conducted to examine the changes of nitr... While many controlled irrigation and drainage techniques have been adopted in China, the environmental effects of these techniques require further investigation. This study was conducted to examine the changes of nitrogen and phosphorus of a flooded paddy water system after fertilizer application and at each growth stage so as to obtain the optimal drainage time at each growth stage. Four treatments with different water level management methods at each growth stage were conducted under the condition of ten-day continuous flooding. Results show that the ammonia nitrogen ( NH4-N ) concentration reached the peak value once the fertilizer was applied, and then decreased to a relatively low level seven to ten days later, and that the nitrate nitrogen (NO^-N) concentration gradually rose to its peak value, which appeared later in subsurface water than in surface water. Continuous flooding could effectively reduce the concentrations of NH^-N , NO3-N, and total phosphorus (TP) in surface water. However, the paddy water disturbance, in the process of soil surface adsorption and nitrification, caused NH]-N to be released and increased the concentrations of NH4-N and NO^-N in surface water. A multi-objective controlled drainage model based on environmental factors was established in order to obtain the optimal drainage time at each growth stage and better guide the drainage practices of farmers. The optimal times for surface drainage are the fourth, sixth, fifth, and sixth days after flooding at the tillering, jointing-booting, heading-flowering, and milking stages, respectively. 展开更多
关键词 ammonia nitrogen nitrate nitrogen PHOSPHORUS optimal drainage time flooded paddy field
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Effects of Seed Maturity of Turf-Type Tall Fescue on the Seed Vigor and the Optimal Harvesting Time 被引量:3
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作者 XU Rong and HAN Jian-guoInstitute of Grassland Science, China Agricultural University, Beijing 100094 , P.R.China 《Agricultural Sciences in China》 CAS CSCD 2003年第4期454-462,共9页
By assay of accelerated aging germination, germination index, vigor index, seedling length, seedling weight, electric conductivity, dehydrogenase activity, ATP content and acid phosphoesterase activity during seed dev... By assay of accelerated aging germination, germination index, vigor index, seedling length, seedling weight, electric conductivity, dehydrogenase activity, ATP content and acid phosphoesterase activity during seed development of turf-type tall fescue, the seed vigor of tall fescue were studied. Combining with seed moisture content and yield, the optimal harvesting time of tall fescue was determined. The results indicated that the seed vigor increased continuously along with seed maturity, and the higher seed vigor was achieved at 19th day after perk anthesis and maintained continuously until 31st day after peak anthesis. At 25th day after peak anthesis, the highest yield of 3 533 kg ha-1 and the good quality of seeds of tall fescue were harvested with 32.19% moisture content. From 22nd to 31st day after peak anthesis, the seed yield of 3 300 kg ha-1 and the good quality seeds of tall fescue were harvested with 40 - 12. 43% moisture content, and the span was the optimal harvesting time. 展开更多
关键词 Turf-type tall fescue Seed vigor optimal harvesting time
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Diurnal Variation of Soil CO2 Efflux and Its Optimal Measuring Time-window of Temperate Meadow Steppes in Western Songnen Plain, China 被引量:2
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作者 YU Xiuli LI Xiujun +4 位作者 XU Linshu WANG Ming ZHANG Jitao JIANG Ming WANG Guodong 《Chinese Geographical Science》 SCIE CSCD 2016年第4期518-526,共9页
In order to study the diurnal variation of soil CO2 effiux from temperate meadow steppes in Northeast China, and determine the best time for observation, a field experiment was conducted with a LI-6400 soil CO2 flux s... In order to study the diurnal variation of soil CO2 effiux from temperate meadow steppes in Northeast China, and determine the best time for observation, a field experiment was conducted with a LI-6400 soil CO2 flux system under five typical plant communi- ties (Suaeda glauca (Sg), Chloris virgata (Cv), Puecinellia distans (Pd), Leymus chinensis (Lc) and Phragmites australis (Pa)) and an alkali-spot land (As) at the meadow steppe of western Songnen Plain. The results showed that the diurnal variation of soil CO2 effiux exhibited a single peak curve in the growing season. Diurnal maximum soil respiration (Rs) often appeared between 1 1:00 and 13:00, while the minimum occurred at 21:00-23:00 or before dawn. Air temperature near the soil surface (Ta) and soil temperature at 10 cm depth (Tlo) exerted dominant control on the diurnal variations of soil respiration. The time-windows 7:00-9:00 could be used as the optimal measuring time to represent the daily mean soil CO2 effiux at the Cv, Pd, Lc and Pa sites. The daily mean soil CO2 effiux was close to the soil COz effiux from 15:00 to 17:00 and the mean of 2 individual soil CO2 effiux from 15:00 to 19:00 at the As and Sg sites, respectively. During nocturnal hours, negative soil CO2 fluxes (CO2 downwards into the soil) were frequently observed at the As and Sg sites, the magnitude of the negative CO2 fluxes were 0.10-1.55 gmol/(m2.s) and 0.10-0.69 gmol/(m2.s)at the two sites. The results im- plied that alkaline soils could absorb CO2 under natural condition, which might have significant implications to the global carbon budget accounting. 展开更多
关键词 soil respiration CQ effiux meadow steppe optimal measurement time negative C02 effiux
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Convergence and Superconvergence of Fully Discrete Finite Element for Time Fractional Optimal Control Problems 被引量:1
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作者 Yuelong Tang 《American Journal of Computational Mathematics》 2021年第1期53-63,共11页
In this paper, we consider a fully discrete finite element approximation for time fractional optimal control problems. The state and adjoint state are approximated by triangular linear fi nite elements in space and &l... In this paper, we consider a fully discrete finite element approximation for time fractional optimal control problems. The state and adjoint state are approximated by triangular linear fi nite elements in space and <em>L</em>1 scheme in time. The control is obtained by the variational discretization technique. The main purpose of this work is to derive the convergence and superconvergence. A numerical example is presented to validate our theoretical results. 展开更多
关键词 time Fractional optimal Control Problems Finite Element Convergence and Superconvergence
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Comparison of time optimal control for two level quantum systems
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作者 Shuang Cong Jie Wen Xubo Zou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第1期95-103,共9页
The time optimal problem for a two level quantum sys-tem is studied. We compare two different control strategies of bang-bang control and the geometric control, respectively, es-pecial y in the case of minimizing the ... The time optimal problem for a two level quantum sys-tem is studied. We compare two different control strategies of bang-bang control and the geometric control, respectively, es-pecial y in the case of minimizing the time of steering the state from North Pole to South Pole on the Bloch sphere with bounded control. The time performances are compared for different param-eters by the individual numerical simulation experiments, and the experimental results are analyzed. The results show that the ge-ometric control spends less time than the bang-bang control does. 展开更多
关键词 geometric control bang-bang control time optimal comparison
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A Fast Approach for Time Optimal and Smooth Trajectory Planning of Robot Manipulators
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作者 Gang Liu Chao Yun 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第5期23-31,共9页
In this paper, a fast approach to generate time optimal and smooth trajectory has been developed and tested. Minimum time is critical for the productivity in industrial applications. Meanwhile, smooth trajectories bas... In this paper, a fast approach to generate time optimal and smooth trajectory has been developed and tested. Minimum time is critical for the productivity in industrial applications. Meanwhile, smooth trajectories based on cubic splines are desirable for their ability to limit vibrations and ensure the continuity of position, velocity and acceleration during the robot movement. The main feature of the approach is a satisfactory solution that can be obtained by a local modification process among each intermal between two consecutive via-points. An analytical formulation simplifies the approach to smooth trajectory and few,iterations are enough to determine the correct values. The approach can be applied in many robot manipulators which require high performance on time and smooth. The simulation and application of the approach on a palletizer robot are performed, and the experimental results provide evidence that the approach can realize the robot manipulators more efficiency and high smooth performance. 展开更多
关键词 trajectory planning cubic spline kinematic constraints interval anatysis time optimal smoothtechnique
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DETERMINATION METHOD OF OPTIMAL SUPPORTING TIME IN HEADING FACE
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作者 杜长龙 曹红波 +1 位作者 王燕宁 张艳 《Journal of Coal Science & Engineering(China)》 1997年第2期41-44,共4页
This paper has put forward a concept of optimal supporting time through analysing the influence of the supporting time in the heading face on the supporting result of surrounding rock.The method Of the optimal Support... This paper has put forward a concept of optimal supporting time through analysing the influence of the supporting time in the heading face on the supporting result of surrounding rock.The method Of the optimal Supporting time determined by graphical method is discussed, and the calculating formula for determining the optimal supporting time through the analysis method is derived. 展开更多
关键词 heading face roadway support optimal supporting time
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TIME AND NORM OPTIMAL CONTROLS:A SURVEY OF RECENT RESULTS AND OPEN PROBLEMS
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作者 H. O. Fattorini 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2203-2218,共16页
We present in this paper a survey of recent results on the relation between time and norm optimality for linear systems and the infinite dimensional version of Pontryagin's maximum principle. In particular, we discus... We present in this paper a survey of recent results on the relation between time and norm optimality for linear systems and the infinite dimensional version of Pontryagin's maximum principle. In particular, we discuss optimality (or nonoptimality) of singular controls satisfying the maximum principle and smoothness of the costate in function of smoothness of the target. 展开更多
关键词 linear control systems in Banach spaces time optimal problem norm optimal problem
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Study on Optimal Fermentation and Storage Time of Soybean Food (Thua-Nao)in Thailand
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作者 Laongdown Sangla Tawadchai Suppadit +1 位作者 Sutad Pintasen Aorawan Wungdeethrum 《Journal of Life Sciences》 2010年第6期46-49,共4页
The soybean cultivar Tadang Muangpai was used to improve the productive quality of Thua-Nao and reduce the concentration of aflatoxin to less than 20 ppb. It was conducted at CMFCRC, Chiangmai, Thailand between Dec. 2... The soybean cultivar Tadang Muangpai was used to improve the productive quality of Thua-Nao and reduce the concentration of aflatoxin to less than 20 ppb. It was conducted at CMFCRC, Chiangmai, Thailand between Dec. 2006 and Mar. 2007. Soybean was boiled for 5 hours and then fermented at different time to create natural bacterial species, mainly Bacillus spp. Thua-Nao could be stored up to 90 days after in storage. Nutritional value, food value, and microorganisms content were investigated during fermentation and storage. Also, aflatoxin content of Thua-Nao was recorded during storage. The results showed that 3 days of soybean fermentation gave the best performance of Thua-Nao in term of nutritional value (protein = 47.12%), food value, and content of Bacillus spp. (2.78 × 10^9 CFU/g). Without being harmed from aflatoxin, Thua-Nao could be stored not more than 23 days in normal room (Tmax. = 33.9 ℃, Tmin. = 15.8 ℃) and not more than 36 days in climate-controlled room (Tmax. = 20 ℃, Tmin. = 15 ℃). 展开更多
关键词 Soybean food Thua-Nao optimal fermentation and storage time nutritional value.
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Urgent one-stage endoscopic treatment for choledocholithiasis related moderate to severe acute cholangitis: A propensity scorematched analysis
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作者 Yang Zhou Yin-Qiu Zhang +4 位作者 Shuai-Jing Huang Yan Liang Xiao Liang Masoom Wali Ya-Dong Feng 《World Journal of Gastroenterology》 SCIE CAS 2024年第15期2118-2127,共10页
BACKGROUND During emergency endoscopic retrograde cholangiopancreatography(ERCP),the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis(AC)due to choledocholithiasi... BACKGROUND During emergency endoscopic retrograde cholangiopancreatography(ERCP),the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis(AC)due to choledocholithiasis are unclear.AIM To investigate the safety and feasibility of one-stage endoscopic treatment for moderate to severe AC.METHODS We enrolled all patients diagnosed with moderate to severe cholangitis due to common bile duct stones from January 2019 to July 2023.The outcomes were compared in this study between patients who underwent ERCP within 24 h and those who underwent ERCP 24 h later,employing a propensity score(PS)frame-work.Our primary outcomes were intensive care unit(ICU)admission rates,ICU length of stay,and duration of antibiotic use.RESULTS In total,we included 254 patients and categorized them into two groups based on the time elapsed between admission and intervention:The urgent group(≤24 h,n=102)and the elective group(>24 h,n=152).Ninety-three pairs of patients with similar characteristics were selected by PS matching.The urgent ERCP group had more ICU admissions(34.4%vs 21.5%,P=0.05),shorter ICU stays(3 d vs 9 d,P<0.001),fewer antibiotic use(6 d vs 9 d,P<0.001),and shorter hospital stays(9 d vs 18.5 d,P<0.001).There were no significant differences observed in adverse events,in-hospital mortality,recurrent cholangitis occurrence,30-d readmission rate or 30-d mortality.CONCLUSION Urgent one-stage ERCP provides the advantages of a shorter ICU stay,a shorter duration of antibiotic use,and a shorter hospital stay. 展开更多
关键词 Acute cholangitis Endoscopic retrograde cholangiopancreatography One-stage treatment optimal time
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Optimal Maintenance Policy for a Storage System with Finite Number of Inspections
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作者 潘郁 伊藤弘道 +1 位作者 中川覃夫 达庆利 《Journal of Southeast University(English Edition)》 EI CAS 2001年第1期22-25,共4页
The expected cost per unit of time for a sequential inspection policy is derived. It still has some difficulties to compute an optimal sequential policy numerically, which minimizes the expected cost of a system with ... The expected cost per unit of time for a sequential inspection policy is derived. It still has some difficulties to compute an optimal sequential policy numerically, which minimizes the expected cost of a system with finite number of inspections. This paper gives the algorithm for an optimal inspection schedule and specifies the computing procedure for a Weibull distribution. Using this algorithm, optimal inspection times are computed as a numerical result. Compared with the periodic point inspection, the policies in this paper reduce the cost successfully. 展开更多
关键词 storage system sequential inspection optimal time sequence
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TIME ASYMPTOTIC BEHAVIOR OF THE BIPOLAR NAVIER-STOKES-POISSON SYSTEM 被引量:15
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作者 Hai-Liang Li Tong Yang Chen Zou 《Acta Mathematica Scientia》 SCIE CSCD 2009年第6期1721-1736,共16页
The bipolar Navier-Stokes-Poisson system (BNSP) has been used to simulate the transport of charged particles (ions and electrons for instance) under the influence of electrostatic force governed by the self-consis... The bipolar Navier-Stokes-Poisson system (BNSP) has been used to simulate the transport of charged particles (ions and electrons for instance) under the influence of electrostatic force governed by the self-consistent Poisson equation. The optimal L^2 time convergence rate for the global classical solution is obtained for a small initial perturbation of the constant equilibrium state. It is shown that due to the electric field, the difference of the charge densities tend to the equilibrium states at the optimal rate (1 + t)^-3/4 in L^2-norm, while the individual momentum of the charged particles converges at the optimal rate (1 + t)^-1/4 which is slower than the rate (1 + t)^-3/4 for the compressible Navier-Stokes equations (NS). In addition, a new phenomenon on the charge transport is observed regarding the interplay between the two carriers that almost counteracts the influence of the electric field so that the total density and momentum of the two carriers converges at a faster rate (1 + t)^-3/4+ε for any small constant ε 〉 0. The above estimates reveal the essential difference between the unipolar and the bipolar Navier-Stokes-Poisson systems. 展开更多
关键词 bipolar Navier-Stokes-Poisson system optimal time convergence rate spectrum analysis total momentum
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LARGE TIME BEHAVIORS OF THE ISENTROPIC BIPOLAR COMPRESSIBLE NAVIER-STOKES-POISSON SYSTEM 被引量:6
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作者 邹晨 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期1725-1740,共16页
The isentropic bipolar compressible Navier-Stokes-Poisson (BNSP) system is investigated in R3 in the present paper. The optimal time decay rate of global strong solution is established. When the regular initial data... The isentropic bipolar compressible Navier-Stokes-Poisson (BNSP) system is investigated in R3 in the present paper. The optimal time decay rate of global strong solution is established. When the regular initial data belong to the Sobolev space H l(R3) ∩ B˙ s 1,1 (R3) with l ≥ 4 and s ∈ (0, 1], it is shown that the momenta of the charged particles decay at the optimal rate (1+t) 1 4 s 2 in L2 -norm, which is slower than the rate (1+t) 3 4 s 2 for the compressible Navier-Stokes (NS) equations [14]. In particular, a new phenomenon on the charge transport is observed. The time decay rate of total density and momentum was both (1 + t) 3 4 due to the cancellation effect from the interplay interaction of the charged particles. 展开更多
关键词 bipolar Navier-Stokes-Poisson system optimal time convergence rate total momentum
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An Experimental Study on the Optimal Timing for the Repair of Incomplete Facial Paralysis by Hypoglossal-facial‘Side'-to-side Neurorrhaphy in Rats 被引量:2
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作者 WANG Bin Bin ZHANG Shao Dong +4 位作者 FENG Jie LI Jun Hua LIU Song LI De Zhi WAN Hong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第6期413-424,共12页
Objective To investigate the optimal timing for the repair of persistent incomplete facial paralysis by hypoglossal-facial ‘side'-to-side neurorrhaphy in rats. Methods A total of 30 adult rats with crushed and bulld... Objective To investigate the optimal timing for the repair of persistent incomplete facial paralysis by hypoglossal-facial ‘side'-to-side neurorrhaphy in rats. Methods A total of 30 adult rats with crushed and bulldog-clamped facial nerve injury were randomly divided into 5 groups(n = 6 each) that were subjected to injury without nerve repair or with immediate repair, 2-week-delayed repair, 4-week-delayed repair, or 8-week-delayed repair. Three months later, the effects of repair in each rat were evaluated by facial symmetry assessment, electrophysiological examination, retrograde labeling, and axon regeneration measurement. Results At 3 months after injury, the alpha angle significantly increased in the group of rats with 4-week-delayed repair compared with the other four groups. Upon stimulation of the facial nerve or Pre degenerated nerve, the muscle action potentials MAPs were recorded in the whisker pad muscle, and the MAP amplitude and area under the curve in the 4-week-delayed repair group were significantly augmented at 3 months post-injury. Similarly, the number of retrograde-labeled motor neurons in the facial and hypoglossal nuclei was quantified to be significantly greater in the 4-week-delayed repair group than in the other groups, and a large number of regenerated axons was also observed. Conclusion The results of this study demonstrated that hemi HN-FN neurorrhaphy performed 4 weeks after facial nerve injury was most effective in terms of the functional recovery of axonal regeneration and activation of facial muscles. 展开更多
关键词 Facial paralysis Hypoglossal-facial nerve anastomosis Nerve autograft optimal time
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