A Discrete Artificial Bee Colony Algorithm for Minimizing the Total Flow Time in the Blocking Flow Shop Scheduling

A discrete artificial bee colony algorithm is proposed for solving the blocking flow shop scheduling problem with total flow time criterion. Firstly, the solution in the algorithm is represented as job permutation. Secondly, an initialization scheme based on a variant of the NEH (Nawaz-Enscore-Ham) heuristic and a local search is designed to construct the initial population with both quality and diversity. Thirdly, based on the idea of iterated greedy algorithm, some newly designed schemes for employed bee, onlooker bee and scout bee are presented. The performance of the proposed algorithm is tested on the well-known Taillard benchmark set, and the computational results demonstrate the effectiveness of the discrete artificial bee colony algorithm. In addition, the best known solutions of the benchmark set are provided for the blocking flow shop scheduling problem with total flow time criterion.

A TABU SEARCH APPROACH TOWARDS CONGESTION AND TOTAL FLOW MINIMIZATION IN OPTICAL NETWORKS

This paper considers rearrangeable multihop lightwave networks whereby each network node is equipped with a number p of transmitters and receivers, and a spectrum of wavelengths is accessible by, and shared among, all nodes by using the Wavelength Division Multiplexing (WDM). Depending on input traffic flow, nodal transmitters and receivers can be re-tuned to create virtual connectivity best suited with respect to a given optimization criterion. We present an efficient heuristic algorithm that combines two criteria for optimization: throughput maximization, as well as total flow minimization. Throughput maximization criterion is equivalent to congestion minimization, while minimizing total flow under the assumption of having links with equal lengths implies minimization of the average number of hops. Taking into account lengths of the links (i.e. link costs proportional with distances), the total flow minimization becomes equivalent to the total delay minimization. Tabu search is implemented as a two-phase strategy dealing with diversification as well as intensification of search. Computational experiments include consecutive runs with different sets of weights associated with the two criteria. Results for a benchmark set of problems are presented.

Influence of the total gas flow rate on high rate growth microcrystalline silicon films and solar cells

This paper reports that high-rate-deposition of microcrystalline silicon solar cells was performed by very-highfrequency plasma-enhanced chemical vapor deposition. These solar cells, whose intrinsic μc-Si：H layers were prepared by using a different total gas flow rate （Ftotal）, behave much differently in performance, although their intrinsic layers have similar crystalline volume fraction, opto-electronic properties and a deposition rate of - 1.0 nm/s. The influence of Ftotal on the micro-structural properties was analyzed by Raman and Fourier transformed infrared measurements. The results showed that the vertical uniformity and the compact degree of μc-Si：H thin films were improved with increasing Ftotal. The variation of the microstructure was regarded as the main reason for the difference of the J V parameters. Combined with optical emission spectroscopy, we found that the gas temperature plays an important role in determining the microstructure of thin films. With Ftotal of 300 sccm, a conversion efficiency of 8.11% has been obtained for the intrinsic layer deposited at 8.5 A/s （1 A=0.1 nm）.

Voluntary Thigh Muscle Strength with Resection Stump-Dependent Blood Flow and Vasodilation in an Amputated Lower Leg with Total Surface Bearing Prosthesis during Dynamic Knee Extensor: A Case Trial

Background: The magnitude of the hyperemic response due to repeated thigh stump exercise on incremental contraction intensity might be useful information in localized exercise tolerance for devising cardiovascular physical therapy for amputees. The effect of exercise on amputated leg blood flow (LBF) may potentially be altered due to voluntary muscle contractions after loss of the lower leg compared with the healthy leg. Case Presentation: A 57-year-old male patient with Burger disease attempted 3 min unilateral repeat/dynamic knee extensor exercise at a target muscle contraction frequency (1 s thigh muscle contraction and 1 s relaxation, 90 repetitions) with each leg <right transtibial amputated leg (AL) using a total surface-bearing prosthesis (TSB) and left non-AL> at six different contraction intensities (rubber resistance belt). Simultaneous measurement of blood velocity/flow (Doppler ultrasound) in the femoral artery, blood pressure, leg vascular conductance (LVC), and peak muscle strength (PMS) were performed during the 3 min exercise period. The maximum voluntary contraction by one-legged isometric knee muscle contraction was 14.7 kg in non-AL and 7.9 kg in the AL with prosthesis. The relative PMS was defined as “PMS/maximum voluntary contraction × 100 (%)”. Pre-exercise LBF was lower in the AL (200 ± 25 ml/min) than the non-AL (275 ± 74 ml/min). Both the non-AL and AL showed good positive linear relationships between absolute-/relative-PMS and LBF or LVC during 30 s at steady-state before the end of the exercise period. Furthermore, there was also similarity seen in the increase rate in LBF and/or LVC for the incremental relative PMS compared with the absolute PMS. Conclusion: In this case, the muscle strength depended on blood flow increase/vasodilation was seen in this “AL” using a TSB prosthesis for repeated dynamic knee extensor exercise. The present amputee’s limb muscle strengthening with the resection stump closely related to the degree of hyperemia in the amputated limb.

Continuous flow analysis of dissolved total phosphorus in seawater by UVK_(2)S_(2)O_(8) online digestion method

Several methods for analysis of dissolved total phosphorus in seawater were reviewed. Discussions were focused on UVirradiation and persulphate oxidation methods which are the most popular dissolved organic phosphorus determinationmethods presently. The compounds used for the phosphorus recovery test were categorized into three groups accordingto their chemical structure. It was found that low power UV irradiation can decompose POC or PC bonds efficientlybut may be inefficient for POP bonds. Heating-bath in acid condition is useful for decomposing POP bonds. Usingthe continuous flow analysis system (Auto-analyzer II), UV digestion and heating-bath, series experiments were carriedout based on the above analysis. Eleven model compounds were employed for the phosphorus recovery test and thefactors influencing the decomposition efficiency of dissolved compounds containing phosphorus were clarified. Finally,the optimal design for determination of dissolved total phosphorus in seawater based on the routine continuous flowanalysis system was presented. For the organic mono-phosphate, the recovery is more than 90% and a recovery of33%~51% was obtained for inorganic or organic polyphosphates. Up to now, this is the highest decompositionefficiency for dissolved phosphorus based on the continuous flow analysis system.

Improved Angina Symptoms Following Coronary Sinus Flow Reducer Implantation in a Patient with Refractory Angina and Chronic Total Occlusion: A Case Report

Background: Due to the aging population and increased survival of the patients with coronary artery disease, there is an increasing number of patients with debilitating angina refractory to optimal medical treatment who are not candidates for revascularization. In case of low ischemic load, the treatment of stable refractory angina is aimed at symptom reduction. There are several new treatment methods targeting myocardial ischemia available, including coronary sinus flow reducer (CFR) implantation. Case Report: We report a case of a patient suffering from CCS class IV angina despite optimal medical therapy, with further revascualrization options exhausted, who was successfully treated with coronary sinus flow reducer (CFR). Besides technical skill to reach ostium of coronary sinus, the most important technical tip is precise positioning of the CFR. The reduction of angina symptoms started after epithelisation of CFR frame, usually 6 - 7 weeks after implantation. At 6-month follow-up, the patient reported a marked reduction of angina symptoms, with CCS grade improving by three classes (from IV to I). At 10-month follow-up, the sustainment of CCS grade I angina symptoms was reported by the patient. Conclusions: We conclude that CFR can be safely and successfully implanted in patients suffering from refractory angina. Considerable improvements in CCS grade may be experienced in certain cases.

Relationship between the Interannual Variations of Total Ozone in the Northern Hemisphere and the QBO of Basic Flow in the Tropical Stratosphere

The harmonic analyses of monthly mean total ozone in the atmosphere over the Northern Hemisphere for 26 years (1960-1985) are made by using the Fourier expansion. The analysed results show that there is obviously a quasi-biennial oscillation (QBO) in the interannual variations of the amplitudes of total ozone. Generally, the amplitudes of wavenumber 1 and 2 during the westerly of the equatorial QBO are larger than those during the easterly. In the early winter, the amplitude of wavenumber 1 during the easterly phase is larger, and in the late winter, it is larger during the westerly phase. These are in good agreement with the observational distributions.

多阶段混合Flow Shop调度问题及其遗传求解算法

针对多阶段混合Ｆｌｏｗ Ｓｈｏｐ 调度问题的一般结构和不同的调度目标函数，提出混合整数规划模型，并基于问题的结构特点设计了遗传求解算法。计算实验结果表明。

Scheduling a three-machine no-wait flowshop with separated setup time

In many practical flowshop production environments, there is no intermediate storage space available to keep partially completed jobs between any two machines. The workflow has to be continuous, implying that the no-wait conditions must be abided, which is typical in steel and plastic production. We discuss the three-machine no-wait flowshop scheduling problem where the setup times are considered as separated from processing times and sequence independent. The scheduling goal is to minimize the total flowtime. An optimal property and two heuristic algorithms for this problem are proposed. Evaluated over a large number of problems, the proposed heuristics are found that they can yield good solutions effectively with low computational complexity, and have more obvious advantage for the large size problem compared with the existing one.

极小化加权完工时间和的Flowshop问题的算法(英文)

本文讨论了极小化加权完工时间和的Flowshop问题.我们给出了一个最坏情况误差界为m的启发式算法,对于m=2的情况,如果工件具有一致权因子,即pi<pj意味着wi≥wj,(i,j=1,2,…,n).最坏情况误差界为2β/α+β,其中α和β分别是全部工序加工时间的最小值和最大值.此外,分析了m=2的两种特殊情况,给出了多项式算法.

各机器具有相同加工时间的Flow Shop成组排序问题

本文讨论了m台机器的FolwShop成组排序问题,工件在不同机器上的加工时间相同,目标函数为极小化完工时间和。给出了一个多项式时间可解的最优算法。

Hybrid Discrete Harmony Search Algorithm for Flow Shop Scheduling with Limited Buffers

The flow shop scheduling problem with limited buffers( LBFSP) widely exists in manufacturing systems. A hybrid discrete harmony search algorithm is proposed for the problem to minimize total flow time. The algorithm presents a novel discrete improvisation and a differential evolution scheme with the jobpermutation-based representation. Moreover,the discrete harmony search is hybridized with the problem-dependent local search based on insert neighborhood to balance the global exploration and local exploitation. In addition, an orthogonal experiment design is employed to provide a receipt for turning the adjustable parameters of the algorithm. Comparisons based on the Taillard benchmarks indicate the superiority of the proposed algorithm in terms of effectiveness and efficiency.

Tip Clearance Flows in Turbine Cascades

This article describes the effects of some factors on the tip clearance flow in axial linear turbine cascades. The measurements of the total pressure loss coefficient are made at the cascade outlets by using a five-hole probe at exit Mach numbers of 0.10, 0.14 and 0.19. At each exit Mach number, experiments are performed at the tip clearance heights of 1.0%, 1.5%, 2.0%, 2.5% and 3.0% of the blade height. The effects of the non-uniform tip clearance height of each blade in the pitchwise direction are also studied. The results show that at a given tip clearance height, generally, total pressure loss rises with exit Mach numbers proportionally. At a fixed exit Mach number, the total pressure loss augments nearly proportionally as the tip clearance height increases. The increased tip clearance heights in the tip regions of two adjacent blades are to be blame for the larger clearance loss of the center blade. Compared to the effects of the tip clearance height, the effects of the exit Mach number and the pitchwise variation of the tip clearance height on the cascade total pressure loss are so less significant to be omitted.

折扣加权总完工时间的调整时间可分离无等待Flow Shop排序问题

研究 3台机器调整时间可分离的无等待 Flow Shop排序问题 ,目标函数为极小化折扣加权总完工时间。对某些特殊情况 ,给出问题存在多项式最优算法的充分条件。在此条件下得到求解调整时间可分离的无等待 Flow Shop排序问题的分派规则。

求解中间存储有限Flow Shop调度问题的离散群搜索优化算法

针对中间存储有限的Flow Shop调度问题,提出了一种离散群搜索优化算法来最小化工件加工的总流水时间。该算法首先采用基于工件排列的离散编码方式,使得能够直接求解离散的调度问题;其次提出了新的初始化方法,确保了初始种群既具有一定的多样性,又有较好的性能;还引入了离散差分进化的思想,增强了算法的运算效率与搜索能力。最后使用正交设计的方法设置算法参数,通过对Taillard算例的仿真计算,验证了本文算法的优越性。

用AGLA算法求解一类以TFT为目标的模糊Flow Shop调度问题

针对一类加工时间不确定的以总流经时间(TFT)为目标的置换Flow Shop调度问题,应用模糊数学的方法表示加工时间的不确定性,提出了一种改进的智能算法——异步遗传局部搜索算法(AGLA)。该算法初始种群的一个解由构造型启发式算法产生,其他解随机产生;通过引入一个加强的变邻域搜索机制和一个简单的交叉算子,对种群执行异步进化操作(AE);算法最后加入重启机制防止陷入局部极小。仿真实验结果验证了AGLA解决模糊Flow Shop问题的有效性。

求解Flow Shop调度问题的混合禁忌搜索算法

针对目标为总完工时间的FlowShop调度问题,提出了一个启发式算法与禁忌搜索算法相结合的混合禁忌搜索算法HTA(Hybrid Tabu Algorithm):将RZ算法的结果作为初始解,然后采用禁忌搜索算法对其进行改进.实验结果表明:在最好调度的获取能力、所得调度的平均质量及算法的稳定性方面,HTA算法均是最优的.

Numerical Investigation of Electrohydrodynamic (EHD) Flow Control in an S-Shaped Duct

An electrohydrodynamic （EHD） method, which is based on glow discharge plasma, is presented for flow control in an S-shaped duct. The research subject is an expanding channel with a constant width and a rectangular cross section. An equivalent divergence angle and basic function are introduced to build the three-dimensional model. Subsequently, the plasma physical models are simplified as the effects of electrical body force and work （done by the force） on the fluid near the wall. With the aid of FLUENT software, the source terms of momentum and energy are added to the Navier-Stokes equation. Finally, the original performance of three models （A, B and C） is studied, in which model A demonstrates better performance. Then EHD control based on model A is discussed. The results show that the EHD method is an effective way of reducing flow loss and improving uniformity at the duct exit. The innovation in this study is the assessment of the EHD control effect on the flow in an S-shaped duct. Both the parametric modeling of the S-shaped duct and the simplified models of plasma provide valuable information for future research on aircraft inlet ducts.

Flow shop排序问题F2|prmu|∑ω_jC_j的一个启发式算法

给出Ｆｌｏｗ ｓｈｏｐ排序问题Ｆ２｜ｐｒｍｕ｜∑ωｊＣｊ的一个启发式算法，其最坏情况的界为２，且是 紧界．此外。

Flow shop排序问题Fm|prmu|∑W_jC_j的一个启发式算式

本文给出了 Flow shop排序问题 F m| p rmu| ∑ Wj Cj 的一个启发式算式 ,其最坏情况的界为 m,且是紧界。