摘要：Water-spraying is regarded as an effective method to reduce the weight loss of product during vacuum cooling *** study aimed to investigate the effect of vacuum cooling factors on the weight loss of postharvest broccoli,and attempted to optimize the treatment conditions by simulated annealing(SA)*** algorithm based on simulated annealing meta-heuristic technique was developed to identify the optimum condition for vacuum cooling treatment of *** demonstrated that the SA algorithm could adjust well with the simulation of the broccoli cooling *** best condition was at 200 Pa of pressure,274 g broccoli,6% of water volume and 40 min processing *** this condition,a product with only 0.35% of weight loss and 1.48℃ final temperature was *** developed method may help to effectively control the weight loss during vacuum cooling process and reducing the economic loss.

摘要：Virtual topology of WDM optical networks is often designed for some specific traffic matrix to get the best network performance. When traffic demand imposed on WDM optical networks changes, the network performance may degrade and even become unacceptable. So virtual topology need to be reconfigured. In previous works, virtual topology is reconfigured to achieve the best network performance, in which a large number of lightpaths need to be set up or torn down. In this paper, we try to get a tradeoff between the network performance and traffic disruption (or implementing cost). The problem of virtual topology reconfiguration for changing traffic patterns is formulated as an optimization problem and a mixed integer linear programming (MILP) algorithm is presented. Numerical results show that a large cost reduction of reconfiguration can be achieved at the expense of network performance.

摘要：An optimized design of laser range finding system using the self-mixing effect in a single-mode verticalcavity surface-emitting laser （VCSEL） is proposed. In order to improve the ranging accuracy and expand dynamic measurement range, we apply difference frequency analog phase-locked loop （PLL） instead of fast Fourier transform （FFT） to process signal, and choose the optimum triangular wave frequency .fm= 500 Hz and small modulation current △Ip p = 0.28 mA to modulate single-mode VCSEL. The experiment results show that, without controlling the laser＇s temperature, the ranging accuracy is better than 2 mm and the measurement dynamic range is as large as 50-500 mm when the sampling time is 0.1 s and the room temperature is 0--55℃.

摘要：Engineering designs for mountainous highways emphasize compliance checking to ensure safety. However, relying solely on compliance checking may lead designers to minimize costs at the expense of high risk indicators, since the overall risk level of the highway design is unknown to the designers. This paper describes a method for the simultaneous consideration of traffic safety risks and the associated cost burden related to the appropriate planning and design of a mountainous highway. The method can be carried out in four steps: First, the highway design is represented by a new parametric framework to extract the key design variables that affect not only the life-cycle cost but also the operational safety. Second, the relationship between the life-cycle cost and the operational safety risk factors is established in the cost-estimation functions. Third, a fault tree analysis (FTA) is introduced to identify the traffic risk factors from the design variables. The safety performance of the design solutions is also assessed by the generalized linear-regression model. Fourth, a theory of acceptable risk analysis is introduced to the traffic safety assessment, and a computing algorithm is proposed to solve for a cost-efficient optimal solution within the range of acceptable risk, in order to help decision-makers. This approach was applied and examined in the Sichuan–Tibet Highway engineering project, which is located in a complex area with a large elevation gradient and a wide range of mountains. The experimental results show that the proposed approach significantly improved both the safety and cost performance of the project in the study area.

摘要：As the demand for energy continues to increase, shale gas, as an unconventional source of methane （CH4）,shows great potential for commercialization. However, due to the ultra-low permeability of shale gas reser-voirs, special procedures such as horizontal drilling, hydraulic fracturing, periodic well shut-in, and carbondioxide （C02） injection may be required in order to boost gas production, maximize economic benefits, andensure safe and environmentally sound operation. Although intensive research is devoted to this emergingtechnology, many researchers have studied shale gas design and operational decisions only in isolation. Infact, these decisions are highly interactive and should be considered simultaneously. Therefore, the researchquestion addressed in this study includes interactions between design and operational decisions. In thispaper, we first establish a full-physics model for a shale gas reservoir. Next, we conduct a sensitivity analysisof important design and operational decisions such as well length, well arrangement, number of fractures,fracture distance, C02 injection rate, and shut-in scheduling in order to gain in-depth insights into the com-plex behavior of shale gas networks. The results suggest that the case with the highest shale gas productionmay not necessarily be the most profitable design; and that drilling, fracturing, and CO2 injection have greatimpacts on the economic viability of this technology. In particular, due to the high costs, enhanced gas re-covery （EGR） using CO2 does not appear to be commercially competitive, unless tax abatements or subsidiesare available for CO2 sequestration. It was also found that the interactions between design and operationaldecisions are significant and that these decisions should be optimized simultaneously.

摘要：Networks-on-chip （NoC） is a promising communication architecture for next generation SoC. The size of buffer used in on-chip routers impacts the silicon area and power consumption of NoC dominantly. It is important to plan the total buffer-size and each router buffer-allocation carefully for an efficient NoC design. In this paper, we propose two buffer planning algorithms for application-specific NoC design. More precisely, given the traffic parameters and performance constraints of target application, the proposed algorithms automatically determine minimal buffer budget and assign the buffer depth for each input channel in different routers. The experimental results show that the proposed algorithms can significantly reduce total buffer usage and guarantee the performance requirements.

摘要：This article, in order to improve the deformation homogeneity in aerospace forgings, proposes an approach that combines the fnite element method （FEM） and the response surface method （RSM） to optimize the preform shapes. New expressions that take into account the influences of equivalent effective strain distribution are developed to evaluate the homogeneity of deformation distribution in aerospace forgings. In order to reduce the number of design variables, the domain-division method is put forward to determine the optimal design variables. On the basis of FEM results, the RSM is used to establish an approximate model to depict the relationship between the responses （deformation homogeneity and die underfilling） and the design variables repre- sented by geometric parameters of the preform shape. With a typical aeroengine disk as an example, the proposed method is verified by achieving an optimal combination of design variables. By comparing the preform shape obtained with the proposed method to that with the existing one, it is evidenced that the former could achieve more homogeneous deformation in forging.

摘要：针对2维电子光学多参量优化问题,采用微动粒子群优化算法,在给出目标电子轨迹和优化范围的前提下,可以得到趋近于该电子轨迹的真空边界和聚束磁结构。该算法分为前后两阶段:第一阶段采用前后试探法(微动),同时参照最优粒子的信息;第二阶段采用标准粒子群优化算法。针对涉及多个相关参量的电子光学设计问题,标准粒子群优化算法仅能保证以较高概率收敛到局部最佳解,而微动粒子群优化算法能以较高概率收敛到全局最佳解,并且展现了多核计算机在电子光学设计上的潜力。初步的软件试验显示:消耗人类工程师几周时间的电子光学设计问题,用微动粒子群算法在普通个人计算机上几十小时就能完成。

摘要：The influence on the stiffness modulus of composites exerted by the volume fraction of reinforcers, aspect ratio, the modulus ratio of the whisker to the matrix, the effect of reinforcers orientation and heat treatment state is discussed, the quantificational relations between microstructure parameters of the short-fiber/whisker reinforced metal matrix composite and its macro mechanical properties are built, and an optimal design method of micro-structure parameters about original isotropy and singularity tropism distribution of the whisker reinforced metal matrix composite is developed. Typical optimal design examples concerning the micro-structure parameter of this kind of material are presented.

摘要：在设计优化中,确定性优化由于没有考虑输入量的不确定性,其优化结果可能不可靠(不安全),因此基于可靠性的设计优化(reliability-based design optimization,RBDO)得到关注。然而可靠性设计优化计算量大,尤其对于高维问题。基于此,提出一种新方法——改进拉丁超立方体取样(Latin hypercube sampling,LHS)方法,该方法可利用先前迭代步骤已用的取样点,从而降低计算量。其中可靠性指数通过基于漫射近似(diffuse approximation,DA)的一阶可靠性方法(first-order reliability method,FORM)计算得到。最后用两个数学实例验证该方法可以极大地降低RBDO问题的计算量。