Hybrid evolutionary algorithm for no-wait flow shops to minimize makespan and total flowtime

The NP-hard no-wait flow shop scheduling problems with makespan and total flowtime minimization are considered. Objective increment properties of the problems are analyzed. A non-dominated classification method is introduced to class population individuals into Pareto fronts to improve searching efficiency. Besides investigating the crowding distance and the elitist solution strategy, two effective bi-criteria local search procedures based on objective increments are presented to improve searching effectiveness. Based on the properties and methods, a hybrid evolutionary algorithm is proposed for the considered problems and compared with the best existing algorithms. Experimental results show that the proposed algorithm is effective with high efficiency.

Objective increment based metaheuristic for total flowtime minimization in no-wait flowshops

To solve the NP-complete no-wait flowshop problems, objective increment properties are analyzed and proved for fundamental operations of heuristics. With these properties, whether a new generated schedule is better or worse than the original one is only evaluated by objective increments, instead of completely calculating objective values as the traditional algorithms do, so that the computational time can be considerably reduced. An objective increment-based hybrid genetic algorithm （IGA） is proposed by integrating the genetic algorithm （GA） with an improved various neighborhood search （VNS）as a local search. An initial solution generation heuristic（ISG） is constructed to generate one individual of the initial population. An expectation value-based selection mechanism and a crossover operator are introduced to the mating process. The IGA is compared with the traditional GA and two best-so-far algorithms for the considered problem on 110 benchmark instances. An experimental results show that the IGA outperforms the others in effectiveness although with a little more time consumption.

Tabu search for no-wait flowshop scheduling problem to minimize maximum lateness

In order to solve the no-wait flowshop scheduling problem to minimize the maximum lateness,three job-block-based neighborhoods are proposed,among which the block exchange neighborhood have a size of O（n4）while the block swap and the simplified block exchange neighborhoods have a size of O（n3）.With larger sizes than the existing neighborhoods,the proposed neighborhoods can enhance the solution quality of local search algorithms.Speedup properties for the neighborhoods are developed,which can evaluate a neighbor in constant time and explore the neighborhoods in time proportional to their proposed sizes. Unlike the dominance-rule-based speedup method,the proposed speedups are applicable to any machine number.Three neighborhoods and the union of block swap and the simplified block exchange neighborhoods are compared in the tabu search.Computational results on benchmark instances show that three tabu search algorithms with O（n3）neighborhoods outperform the existing algorithms and the tabu search algorithm with the union has the best performance among all the tested algorithms.

A low-power high-throughput link splitting router for NoCs

In this paper, we propose a technique for lowering the latency of the communication in a NoC （network on chip）. The technique, which can support two qualities of service （QoS）, i.e., the guaranteed throughput （GT） and best effort （BE）, is based on splitting a wider link into narrower links to increase throughput and decrease latency in the NoC. In addition, to ease the synchronization and reduce the crosstalk, we use the l-of-4 encoding for the smaller buses. The use of the encoding in the proposed NoC architecture considerably lowers the latency for both BE and GT packets. In addition, the bandwidth is increased while the power consumption of the links is reduced.

An efficient priority service model with two-level-polling scheme

This paper considers an efficient priority service model with two-level-polling scheme which the message packets conform to the discrete-time Geom/G/1 queue with multiple vacations and bulk arrival. By the embedded Markov chain theory and the probability generating function method, we set up the mathematics functions and give closed form expressions for obtaining the mean cyclic period （MCP）, the mean queue length （MQL） and the mean waiting time （MWT） characteristics, the analytical results are also verified through extensive computer simulations. The performance analysis reveals that this priority polling scheme can gives better efficiency as well as impartiality in terms of system characteristics, and it can be used for differentiating priority service to guarantee better QoS and system stability in design and improvement of MAC protocol.

Collaborative Problem in Multi-agent System

In the MAS, system goal task can be decomposed into many transactions, which will be achieved by special agents distributed in different physical space. Due to complex coupling relations among transactions, transactions may form Waiting-Circle resulting in deadlock. Concerning the problem, this paper proposes two theorems developed for Waiting-Circle detection in transaction set and ensures the implement of goal task decomposition result. Furthermore, Circle-First Search is put forward to search all of the Waiting-Circle, which prnvide the basic guideline for decomposing goal task again and eliminate Waiting-Circle.

Adult-to-adult living donor liver transplantation for acute liver failure in China

AIM:To investigate the long-term outcome of recipients and donors of adult-to-adult living-donor liver transplantation(AALDLT) for acute liver failure(ALF).METHODS:Between January 2005 and March 2010,170 living donor liver transplantations were performed at West China Hospital of Sichuan University.All living liver donor was voluntary and provided informed consent.Twenty ALF patients underwent AALDLT for rapid deterioration of liver function.ALF was defined based on the criteria of the American Association for the Study of Liver Diseases,including evidence of coagulation abnormality [international normalized ratio(INR) ≥ 1.5] and degree of mental alteration without pre-ex-isting cirrhosis and with an illness of < 26 wk duration.We reviewed the clinical indications,operative procedure and prognosis of AALDTL performed on patients with ALF and corresponding living donors.The potential factors of recipient with ALF and corresponding donor outcome were respectively investigated using multivariate analysis.Survival rates after operation were analyzed using the Kaplan-Meier method.Receiver operator characteristic(ROC) curve analysis was undertaken to identify the threshold of potential risk factors.RESULTS:The causes of ALF were hepatitis B(n = 18),drug-induced(n = 1) and indeterminate(n = 1).The score of the model for end-stage liver disease was 37.1 ± 8.6,and the waiting duration of recipients was 5 ± 4 d.The graft types included right lobe(n = 17) and dual graft(n = 3).The mean graft weight was 623.3 ± 111.3 g,which corresponded to graft-torecipient weight ratio of 0.95% ± 0.14%.The segment Ⅴor Ⅷ hepatic vein was reconstructed in 11 right-lobe grafts.The 1-year and 3-year recipient's survival and graft survival rates were 65%(13 of 20).Postoperative results of total bilirubin,INR and creatinine showed obvious improvements in the survived patients.However,the creatinine level of the deaths was increased postoperatively and became more aggravated compared with the level of the survived recipients.Multivariate analysis showed that waiting duration was independently correlated with increased mortality(P = 0.014).Furthermore,ROC curve revealed the cut-off value of waiting time was 5 d(P = 0.011,area under the curve = 0.791) for determining the mortality.The short-term creatinine level with different recipient's waiting duration was described.The recipients with waiting duration ≥ 5 d showed the worse renal function and higher mortality than those with waiting duration < 5 d(66.7% vs 9.1%,P = 0.017).In addition,all donors had no residual morbidity.Furthermore,univariate analysis did not show that short assessment time induced the high morbidity(P = 0.573).CONCLUSION:Timely AALDLT for patients with ALF greatly improves the recipient survival.However,further systemic review is needed to investigate the optimal treatment strategy for ALF.

An Assessment of the Level of Knowledge of HIV-Infected Patients about Highly Active Antireteroviral Therapy and Waiting Times and Their Influence on Antiretroviral Therapy Adherence at a Primary Healthcare Centre of South Africa

Objectives： The study assessed if the level of knowledge of HIV-infected about HAART and waiting-times in the PHC （primary healthcare） clinic have an influence on antiretroviral adherence. Methods： A descriptive-cross-sectional study was conducted in South Africa. Data collected uses a standardized-questionnaire and face-to-face-exit interviews. Pill-count technique was performed and a value of≥ 95% acceptable. Data were analysed using SPSS. Univariate-factors associated with poor-adherence to knowledge about HAART and waiting times were assessed using ANOVA and p ≤ 0.05 considered statistically significant. Key findings： Of 86 enrolled, 63（73.3%） were females and 23（26.7%） males, with mean-age （± SD） of 35.6（±9.6） years and on HAART for 35.5（± 31.8） months ranging from 1-137. Of these, 27（31.40%） and 25（29.07%） were on WHO stages 2 and 3 respectively. Adherence-rates computed from 32 patients, 23（71.9%） revealed poor adherence-rates. The level of knowledge about HAART in terms of names of tablets, correct-dose, frequency, adverse-effects had no influence on ARV-adherence （p _〉 0.05）. Of 23 non-compliant, 10 （40%） gave the reason of drugs-unavailability, 7（30%） adverse-effects, 5（20%） drugs＇ complexity, and 1（10%） too busy to take them. Waiting areas associated with poor ARV-adherence were reception （p = 0.028）, doctors （p = 0.027）, while nurse＇s station （p = 0.29） and pharmacy （p = 0.43） revealed acceptable ARV-adherence.

OPTIMAL FLOW CONTROL PROBLEM IN AIR TRAFFIC CONTROL:PARTⅠ

The fundamental case is considered in which flights from many destinations must be scheduled for arrival at a single congested airport having limited capacities.An air traffic control(ATC)model is developed in this case.A new and efficient algorithm for the optimal solution of ground holding strategy problem(GHSP)is put forward and verified by a numerical example.

Bitmap lattice index in road networks

A novel technique called the bitmap lattice index(BLI) is proposed, which combines the advantages of a wireless broadcasting environment with a road network. Existing road networks are based on the on-demand method: a server's workload increases as the query request increases when a server sends a client information. To solve this problem, we propose the BLI. The BLI denotes an object and a node as 0 and 1 in the Hilbert curve(HC) map. The BLI can identify the position of a node and an object through bit information; it can also reduce the broadcasting frequency of a server by reducing the size of the index, thereby decreasing the access latency and query processing times. Moreover, the BLI is highly effective for data filtering, as it can identify the positions of both an object and a node. In a road network, if filtering is done via the Euclidean distance, it may result in an error. To prevent this, we add another validation procedure. The experiment is conducted by applying the BLI to kNN query, and the technique is assessed by a performance evaluation experiment.

Measurement of Emissions from Passenger-Picking-up Vehicles at Airport Terminals

Rather than parking at nearby hourly parking lots, many passenger-picking-up vehicles prefer to idle at terminals and/or drive cycling around terminal facilities. As a result, extra vehicle emissions may be produced in an airport area. Even though there are limited studies on such emissions at airports, these estimations were normally based on the date emission models, which might cause bias in emission estimations. This paper proposes an approach to employ the floating car method and Global Positioning System （GPS） to record speeds and acceleration rates of idling and cycling vehicles at airport terminals. The tests were conducted under different time periods and traffic demands with different waiting time. The speeds and acceleration rates are synthesized to yield Vehicle Specific Power＇s （VSP） and Operational Mode （OM） distributions. Utilizing the Environmental Protection Agency （EPA） emission estimation model Motor Vehicle Emission Simulator （MOVES）, pollutants and green house gas emission indexes （e.g. NOx, CO, CO2 and HC） and fuel consumptions can be easily estimated. As an illustration of the proposed approach, the research team collected GPS data at a terminal in Houston William Hobby Airport （HOU）, and calculated the VSP distributions and OM distributions. Emissions of passenger-picking-up vehicles around these congested airport terminals.

Using Pipeline Instructions by Parallel Simulation of Mathematical Models

Simulation is an important and useful technique helping users understand and model real life systems. Once built, the models can run proving realistic results. This supports making decisions on a more logical and scientific basis. The paper introduces method of simulation, and describes various types of its application. The authors used the method of analysis of the creation and implementation of the programme code. The authors compared parallel instruction of computing defined to pipelined instructions. The power of simulation is that a common model can be used to design a large variety of systems. An important aspect of the simulation method is that a simulation model is designed to be repeated in actual computer systems, especially in multicore processors. For this reason, it is important to minimize average waiting time for fetch and decode stage instructions. The objective of the research is to prove that the parallel operation of programme code is faster than sequential operation code on the multi processor architecture. The system modeling uses methods and simulation on the parallel computer systems is very precise. The time benefit gained in simulation of mathematical model on the pipeline processor is higher than the one in simulation of mathematical model on the multi processors computer system.

Stochastic Air Traffic Flow Management for Demand and Capacity Balancing Under Capacity Uncertainty

This paper introduces an innovative approach to the synchronized demand-capacity balance with special focus on sector capacity uncertainty within a centrally controlled collaborative air traffic flow management(ATFM)framework.Further with previous study,the uncertainty in capacity is considered as a non-negligible issue regarding multiple reasons,like the impact of weather,the strike of air traffic controllers(ATCOs),the military use of airspace and the spatiotemporal distribution of nonscheduled flights,etc.These recessive factors affect the outcome of traffic flow optimization.In this research,the focus is placed on the impact of sector capacity uncertainty on demand and capacity balancing(DCB)optimization and ATFM,and multiple options,such as delay assignment and rerouting,are intended for regulating the traffic flow.A scenario optimization method for sector capacity in the presence of uncertainties is used to find the approximately optimal solution.The results show that the proposed approach can achieve better demand and capacity balancing and determine perfect integer solutions to ATFM problems,solving large-scale instances(24 h on seven capacity scenarios,with 6255 flights and 8949 trajectories)in 5-15 min.To the best of our knowledge,our experiment is the first to tackle large-scale instances of stochastic ATFM problems within the collaborative ATFM framework.

献给新世纪的彝歌(组诗)

柏叶是从彝山走出的青年诗人。读柏叶的诗,让我们感受到一个彝族青年诗人对祖国、对故乡以及对自己民族的赤子情怀。传统、现代、未来都在他诗的意象中闪现。他诗中的现代感,是基于优秀彝歌传统上的时代表现;他诗中的传统韵味,又是在对未来进行诗的思考中跳出的火花。读这一组彝歌,我们可以感受到这一切。

SERIES QUEUING NETWORK SCHEDULING APPROACH TO CO-SCHEDULING MODEL OF THREE GORGES-GEZHOU DAM

This paper provides a mathematical model for Three Gorges-Gezhou dam co-scheduling problem, based on full analysis of Three Corges-Gezhou dam＇s actual needs, to maximize the total throughput of Three Gorges-Cezhou dam and the utilization ratio of shiplock area and minimize the total navigation shiplock waiting time under multiple constraints. This paper proposes a series queuing network （SQN） scheduling algorithm to divide the total ships that intend to pass through the shiplocks into four queues and calculate dynamically the weight of priority for each ship. The SQN scheduling algorithm schedules ships according to their priority weights which is determined by the characteristics of each ship, such as length, width, affiliation, waiting time, and so on. In the process, the operation conditions of Gezhou dam related to the navigable shiplocks and the task balancing among different shiplocks also should be considered. The SQN algorithm schedules ships circularly and optimizes the results step by step. Real operation data from our project shows that our SQN scheduling algorithm outperforms the traditional manual scheduling in which the less computational time is taken, the area utilization ratio of the five shiplocks is increased, the waiting time of high-prioritized ships is shorten, and a better balanced and alternating run-mode is provided for the three shiplocks in the Gezhou dam.

The waiting spectra of the sets described by the quantitative waiting time indicators

The waiting spectra of the sets consisting of pairs of sequences with prescribed quantitative waiting time indicators are determined. More precisely,let R(x,y) and R(x,y) be the lower and upper quantitative waiting time indicators of y by x respectively in the symbolic space Σm(integer m 2) and define the level sets Sα,β={(x,y)∈Σ2m:R(x,y)=α,R(x,y)=β},where 0αβ∞,it is shown that the sets Sα,βare all of Hausdorff dimension 2.Besides,some further extensions of this result are also made.

乙型肝炎病毒母婴传播及其阻断研究的现状与存在问题

HBV可经血液、母婴、性接触等多种途径传播,其中母婴传播是我国HBV传播的主要途径之一.乙型肝炎母婴阻断是指通过产前、产时,产后采取一系列措施对新生儿进行保护以减少感染HBV机会的方法.近年来,HBV的母婴阻断取得了较好效果,总体阻断成功率约在90%以上,但仍有一定的失败率,在相关机制、方案优化等方面仍面临一些亟待解决的问题.