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Zusammenfassung Paradoxurus hermaphroditus Männchen habenXY Geschlechtschromosomen, im Unterschied zu den ungewöhnlichenXO Männchen vonHerpestes auropunctatus. Beide Species gehören zu der Familie Viverridae der Ordnung Carnivora und demonstrieren die Robertsonsche Chromosomen-Evolution in Zahl und Struktur.  相似文献   
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In this article, we present a continuous review (s,S) inventory system with a service facility consisting of finite buffer (capacity N ) and a single server. The customers arrive according to a Poisson process. The individual customer's unit demand is satisfied after a random time of service, which is assumed to be exponential. When the inventory level drops to s'an order for Q(= S-s) items is placed. The lead time of reorder is assumed to be exponential distribution. An arriving customer, who finds the buffer is full, enters into the pool of infinite size or leaves the system according to a Bernolli trial. At the time of service completion, if the buffer size drops to a preassigned level L (1 〈 L 〈 N) or below and the inventory level is above s, we select the customers from the pool according to two different policy : in first policy, with probability p (0 〈 p 〈 1) we select the customer from the head of the pool and we place the customer at the end of the buffer; in the second policy, with p (0 〈 p 〈 1) the customer from the pool is transferred to the buffer for immediate service and after completion of his service we provide service to the customer who is in the buffer with probability one. If at a service completion epoch the buffer turns out to be empty, there is at least one customer in the pool and the inventory level is positive, then the one ahead of all waiting in the pool gets transferred to the buffer, and his service starts immediately. The joint probability distribution of the number of customers in the pool, number of customers in the buffer and the inventory level is obtained in the steady-state case. Various stationary system performance measures are computed and total expected cost rate is calculated. A comparative result of two models is illustrate numerically.  相似文献   
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The performance of industrial waste incineration bottom ash in controlled low-strength material (CLSM) was investigated in this paper, as the quarry dust was added. CLSM mixtures were made from the industrial waste incineration bottom ash, quarry dust, and cement. Tests for fresh density, bleeding, compressive strength, shear strength, hydraulic conductivity, and excavatability were carried out. The compressive strength ranges from 60 kPa to 6790 kPa, the friction angle varies from 5° to 19°, and the cohesion is from 4 to 604 kPa. Most of the mixtures are found to be non-excavatable. It is indicated that the quarry dust addition increases the compressive strength and shear parameters, decreases bleeding, and increases the removability modulus.  相似文献   
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基于MATLAB上肢康复机械臂鲁棒控制研究   总被引:1,自引:0,他引:1  
以穿戴上肢康复机械臂(RuPERT)的人体手臂为研究对象,对被控对象建立数学模型,推导鲁棒控制器,基于simMechanics建立仿真模型,实现上肢康复机械臂鲁棒控制系统.考虑到上肢康复机械臂是辅助上肢偏瘫患者进行康复训练并最大限度地诱发患肢的主动作用,控制器中加入上肢偏瘫患者的主动作用,在MATLAB/Simulink的环境下运行.仿真结果表明,控制器能适应各种损伤程度的患者,在存在信号传输时延时,仍能保持响应速度和精度,具有很强的鲁棒}生和自适应性.  相似文献   
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We consider a continuous review perishable (s,S) inventory system with a service facility consisting of a waiting hall of finite capacity and a single server. We assume two types of customers, ordinary and negative, arrive according to a Markovian Arrival Process (MAP). An ordinary customer joins the queue and a negative customer instead of joining the queue removes one ordinary customer from the queue. The removal rule adopted in this paper is RCE (removal of a customer from the end). The individual customer's unit demand is satisfied after a random time of service which is assumed to have a phase-type distribution. The life time of each item and the lead time of the reorders have been assumed to be independent exponential distributions. The joint probability distribution of the number of customers in the system and the inventory level is obtained for the steady state case. Various stationary system performance measures are computed and the total expected cost rate is calculated. The results are illustrated numerically.  相似文献   
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This paper presents gamma stochastic volatility models and investigates its distributional and time series properties. The parameter estimators obtained by the method of moments are shown analytically to be consistent and asymptotically normal. The simulation results indicate that the estimators behave well. The in‐sample analysis shows that return models with gamma autoregressive stochastic volatility processes capture the leptokurtic nature of return distributions and the slowly decaying autocorrelation functions of squared stock index returns for the USA and UK. In comparison with GARCH and EGARCH models, the gamma autoregressive model picks up the persistence in volatility for the US and UK index returns but not the volatility persistence for the Canadian and Japanese index returns. The out‐of‐sample analysis indicates that the gamma autoregressive model has a superior volatility forecasting performance compared to GARCH and EGARCH models. Copyright © 2006 John Wiley _ Sons, Ltd.  相似文献   
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Chronic kidney disease (CKD) represents a major health burden. Its central feature of renal fibrosis is not well understood. By exome sequencing, we identified mutations in FAN1 as a cause of karyomegalic interstitial nephritis (KIN), a disorder that serves as a model for renal fibrosis. Renal histology in KIN is indistinguishable from that of nephronophthisis, except for the presence of karyomegaly. The FAN1 protein has nuclease activity and acts in DNA interstrand cross-link (ICL) repair within the Fanconi anemia DNA damage response (DDR) pathway. We show that cells from individuals with FAN1 mutations have sensitivity to the ICL-inducing agent mitomycin C but do not exhibit chromosome breakage or cell cycle arrest after diepoxybutane treatment, unlike cells from individuals with Fanconi anemia. We complemented ICL sensitivity with wild-type FAN1 but not with cDNA having mutations found in individuals with KIN. Depletion of fan1 in zebrafish caused increased DDR, apoptosis and kidney cysts. Our findings implicate susceptibility to environmental genotoxins and inadequate DNA repair as novel mechanisms contributing to renal fibrosis and CKD.  相似文献   
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