A multi-objective programming model for scheduling emergency medicine residents

Scheduling emergency medicine residents (EMRs) is a complex task, which considers a large number of rules (often conflicting) related to various aspects such as limits on the number of consecutive work hours, number of day and night shifts that should be worked by each resident, resident staffing requirements according to seniority levels for the day and night shifts, restrictions on the number of consecutive day and night shifts assigned, vacation periods, weekend off requests, and fair distribution of responsibilities among the residents. Emergency rooms (ERs) are stressful workplaces, and in addition shift work is well-known to be more demanding than regular daytime work. For this reason, preparing schedules that suit the working rules for EMRs is especially important for reducing the negative impact on shift workers physiologically, psychologically, and socially. In this paper, we present a goal programming (GP) model that accommodates both hard and soft constraints for a monthly planning horizon. The hard constraints should be adhered to strictly, whereas the soft constraints can be violated when necessary. The relative importance values of the soft constraints have been computed by the analytical hierarchy process (AHP), which are used as coefficients of the deviations from the soft constraints in the objective function. The model has been tested in the ER of a major local university hospital. The main conclusions of the study are that problems of realistic size can be solved quickly and the generated schedules have very high qualities compared to the manually prepared schedules, which require a lot of effort and time from the chief resident who is responsible for this duty.     

我国企业开展流程再造应从工作研究开始

由于管理基础工作薄弱，我国很多企业流程再造的努力未获成功。基于企业流程再造与工作研究之间的对比分析，文章提出了运用工作研究领域内的有关理论、经验、方法和工具来帮助我国企业开展流程再造。     

差热法测定钢样表面氧与体内氧的方法研究

本文利用美国LECO公司生产的TC-436氧氮仪,研究了光谱纯Fe2O3,Al2O3和在大量脱氧铁存在下Al2O3的氧释放曲线,得到了它们的分解功率、分解电流和分解计算温度.成功地分离了钢样的表面氧和体内氧,并对钢样不同表面氧的组成做了初步研究.     

Casein Hydrolysate Fractions Act as Emulsifiers in Process Cheese

ABSTRACT: Degrees of hydrolysis and emulsifying activity of casein hydrolysates were the highest at 4 h hydrolysis. The oil-off values of the mixture of hydrolysate (H) or supernatant (S) and traditional emulsifier (T) were not significantly different from the control made with traditional emulsifier, except for S + T = 3:1. Two other samples made with hydrolysate or supernatant only (H or S) showed higher oil-off value than the others (p < 0.05). In flavor property, no difference was found between samples made with traditional emulsifier and those made with the mixture of hydrolysate or supernatant at the ratio of 3 to 1. Therefore, these results indicated that a mixture of the hydrolysate or supernatant and traditional emulsifier might replace a traditional emulsifier in process cheese manufacturing.     

Al-Cu-Fe系初生准晶相凝固过程的电子显微分析

采用包括金相（OM），粉末X射线衍射（XRD），扫描电子显微镜（SEM）观察和透射电子显微（TEM）分析等方法，研究了铸态Al592.Cu36.8Fe3.0Si1.0合金（700℃保温2．5h后水淬）的显微组织及相组成。发现铸锭中存在4种相：准晶I相，τ3相（或φ相），θ－Al2Cu相和η－AlCu相，凝固过程可描述为：初生晶是准晶Ⅰ相；在保温过程中发生包晶或共晶反应（L＋i→τ3(或φ）或L→τ3（或φ）＋i)形成的τ3相（或φ相），呈微畴结构；而剩余液体水淬形成θ－Al2Cu相和η－AlCu 相。     

钢管减阻型内涂层生产工艺及设备

介绍了钢管减阻型内涂层技术的生产工艺和主要设备，给出了内涂层生产线典型的工艺布置，并对主要设备的组成及工作原理进行了介绍。     

铝合金高速船船体建造工艺

简述了ＬＦ１５和ＬＦ１６两种新型船用耐蚀可焊铝合金及其配套焊接材料在实船建造中的应用情况。阐述了铝合金全焊结构船体建造的关键技术及我国铝船体建造的３种方法     

异丁烷与丁烯烷基化反应工艺

讨论了异丁烷与丁烯烷基化反应工艺在清洁燃料生产过程中的地位、作用和发展趋势;简介了目前石油炼制工业中使用的液体酸烷基化工艺;详细介绍了正在研究开发的固体酸烷基化技术;对在烷基化反应中应用的新型固体酸催化材料和新催化反应工艺的探索和进展进行了综述。     

HYSIM软件模拟天然气加工工艺流程的研究(Ⅰ)——系统中无循环物流

本文结合大庆油田天然气矿场加工实际生产装置,讨论了应用HYSIM烃类工艺模拟软件对含有不确定组分的体系进行流程模拟计算的特点、塔设备严格模拟计算过程中输入规定的选择、以及多股流换热器和吸附脱水工艺的模拟计算方法。     

Planning the GMAW process by constraint propagation

Although the gas metal arc welding (GMAW) process is widely used for joining metals, its planning is still a cumbersome task. The planning procedure involves many complex interrelationships among the process variables and depends heavily on empirical knowledge. Therefore, a solution method that allows a convenient way to represent the domain knowledge and evaluate the process variable relationships is needed. Further, the lack of a strong domain theory to quantify these interrelationships is a deficiency in the planning of the GMAW process. This paper presents a solution method that overcomes this deficiency and introduces a convenient knowledge representation scheme. The solution method considers the planning procedure to be a constraint satisfaction problem (CSP). The AC-4 algorithm is used to obtain arc consistency among nodes in the constraint network and the PC-4 algorithm is applied to obtain path consistency in the network. A modified version of the AC-4 algorithm is developed to reduce the search space and correspondingly reduce the computation time. An example is presented to demonstrate the capability of the method and its potential to reduce lead time.