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11.
This paper deals with serial-batching scheduling problems with the effects of deterioration and learning, where time-dependent setup time is also considered. In the proposed scheduling models, all jobs are first partitioned into serial batches, and then all batches are processed on a single serial-batching machine. The actual job processing time is a function of its starting time and position. In addition, a setup time is required when a new batch is processed, and the setup time of the batches is time-dependent, i.e., it is a linear function of its starting time. Structural properties are derived for the problems of minimizing the makespan, the number of tardy jobs, and the maximum earliness. Then, three optimization algorithms are developed to solve them, respectively.  相似文献   
12.
我国地域辽阔,各地光气候有很大区别,为了扩大和提高太阳能与天然光的利用范围及利用效率,采用一种便携式的光谱扫描仪,对我国不同光气候分区的7个代表性城市(昆明、西宁、北京、深圳、南京、南昌和重庆)一天中不同太阳高度角对应时刻的地面直射日光光谱在380~780 nm可见光谱段进行了跟踪观测,分析了不同光气候分区城市一天中不同太阳高度角对应时刻的日光光谱变化规律,比较了不同光气候分区城市的日光光谱曲线,总结了日光光谱辐射强度的影响因素。分析表明:不同光气候分区城市一天中不同太阳高度角对应时刻的日光光谱辐射强度不同,但日光光谱功率的分布和走向基本一致,总体呈先上升后下降的趋势,最大峰值出现在475 nm附近,380~475 nm之间光谱功率分布曲线出现陡升,475~700 nm之间曲线有下降趋势但基本平稳,>700 nm曲线出现了反复的较大起伏;不同光气候分区城市的日光光谱功率分布曲线的分布和走向也基本一致,没有明显的与不同光气候分区直接相关的日光光谱功率分布差异性规律;日光光谱辐射强度与太阳高度角和日面状况密切相关。  相似文献   
13.
鉴于奉化江大桥复杂的空间结构形式,应用通用有限元程序Marc和杆系单元建立有限元模型,分析其在各种荷载条件下的强度、刚度和稳定性,确定各结构单元的材料性质、截面几何性质、边界条件等因素,然后计算其在各荷载工况下的位移和失稳形态.结果表明:该桥的刚度和稳定性满足安全要求  相似文献   
14.
《Physics letters. A》1997,235(4):335-340
A new Lax operator is proposed from the viewpoint of constructing the integrable hierarchies related with the N = 2 super Wn algebra. It is shown that the Poisson algebra associated to the second Hamiltonian structure for the resulting hierarchy contains the N = 2 super Virasoro algebra as a proper subalgebra. The simplest cases are discussed in detail. In particular, it is proved that the supersymmetric two-boson hierarchy is one of the N = 2 supersymmetric KdV hierarchies. Also, a Lax operator is supplied for one of the N = 2 supersymmetric Boussinesq hierarchies.  相似文献   
15.
The fluorescence quenching of 2-naphthyl-substituted 1,3-diketoboronates (2-NDKB) by naphthalene in heptane is accompanied by exciplex emission. The exciplex formation occurs irreversibly because of the high electron affinity of 2-NDKB. In one case the exciplex fluorescence decay reveals the existence of ground state rotamers.  相似文献   
16.
该研究应用红外热像法测量绿化屋顶的表面温度,进而分析屋顶绿化对热环境的影响。通过采集斜坡屋顶绿化、轻型屋顶绿化和蓄水覆土屋顶绿化在阴天、雨后一天、晴天三种天气条件下的红外热像图,分析对比三种绿化屋顶在同一天内及三种不同天气条件下的温度变化。结果表明绿化屋顶表面温度的变化主要受太阳辐射和气温的影响,而蓄水覆土绿化屋顶的表面温度还受到其含水量的影响;屋顶绿化在夏季天气条件下可有效降低屋顶的表面温度、减小温度波动幅度,有利于改善城市热环境。  相似文献   
17.
Airport noise insulation programmes (NIPs) implement active measures for reducing the amount of noise to which people are exposed without impacting the operating capacity of an airport. This is the reason why they are one of the most extended actions adopted internationally by airport authorities to fight noise in airport surroundings.Beyond the assumption that a correct implementation of the NIP will significantly reduce sound exposure, this research aims to determine the efficacy of the NIP as a result of the beneficiaries’ subjective perception in terms of satisfaction, and the reduction of the reported annoyance.A telephone survey was carried out in more than 650 dwellings in the surroundings of several Spanish Airports (Alicante, Bilbao, Grand Canary, Malaga, Palma de Mallorca). The results have shown that: (a) the beneficiaries have a generally positive perception regarding the actions implemented, (b) they are quite satisfied regarding the insulation of the façades after NIP implementation, (c) they report a reduction of the annoyance, but (d) they still perceive aircraft noise as a source of disturbance.The statistical analysis of the results has also shown that there are some non-acoustic factors influencing citizens’ perception of NIPs. Factors such as the aesthetic of windows, or the reliability and professionalism of the workers and technicians involved in the NIP, have been shown to modify people’s reaction. But, the dissatisfaction with legal aspects of Spanish regulations concerning a lower protection of some practical spaces (like, bathrooms and kitchens that have been left out in many cases) has been found to be the factor most affecting people’s response.  相似文献   
18.
19.
The basic concepts of the parking reservation system and parking revenue management system are discussed in this paper. The proposed “intelligent” parking space inventory control system that is based on a combination of fuzzy logic and integer programming techniques makes “on line” decisions whether to accept or reject a new driver’s request for parking. In the first step of the proposed model, the best parking strategies are developed for many different patterns of vehicle arrivals. These parking strategies are developed using integer programming approach. In the second step, learning from the best strategies, specific rules are defined. The uniqueness of the proposed approach is that the rules are derived from the set of chosen examples assuming that the future traffic arrival patterns are known. The results were found to be close to the best solution assuming that the future arrival pattern is known.  相似文献   
20.
为改进湿法消解有机质含量偏高土壤样品的方法,通过电感耦合等离子体质谱(ICP-MS)对比了双氧水-氢氟酸-硝酸(H2O2-HF-HNO3)、盐酸-硝酸-氢氟酸(HCl-HNO3-HF)、王水-逆王水-硝酸-氢氟酸(NO2Cl-H2[(N3O8)Cl]-HNO3-HF)、双氧水-盐酸-硝酸-氢氟酸(H2O2-HCl-HNO3-HF)以及烧失量法-硝酸-氢氟酸(LOI-HNO3-HF)5种不同消解体系对国家土壤成分分析标准物质GSS-1a-GSS-8a样品中铜(Cu)、铬(Cr)、铅(Pb)、镉(Cd)、镍(Ni)、锌(Zn)等重金属元素的萃取效率。以103Rh作为ICP-MS测定时的内标元素,不同测定元素选择合适的监测模式,结果表明,设定3 ℃·min-1升温速率,选择550 ℃,煅烧恒温时长3 h,冷却后再用硝酸和氢氟酸进行消解时,Cu,Cr,Pb,Cd,Ni和Zn消解效果最好,加标回收率实验结果表明,标准物质测定值与标准值之间无显著差异,加标回收率为91%~105%,表明该方法的准确度和精密度均符合要求,双氧水-氢氟酸-硝酸(H2O2-HF-HNO3)体系和双氧水-盐酸-硝酸-氢氟酸(H2O2-HCl-HNO3-HF)体系中由于双氧水受热分解剧烈,消解液易溅出到电热板上导致测试结果偏低;盐酸-硝酸-氢氟酸(HCl-HNO3-HF)体系和王水-逆王水(硝酸-氢氟酸(NO2Cl-H2[(N3O8)Cl]-HNO3-HF)消解体系的测试结果稳定性较差,可能是Cl-对仪器的测试产生了质谱干扰,且在敞开体系中,Cl-易与Cr6+形成CrO2Cl2挥发至空气中,致使Cr元素测试结果偏低,因此在消解土壤样品时最好避免大量Cl-的引入。同时将以上方法也应用到采自于大九湖泥炭地高有机质的土壤样品的对比分析,结果均表明烧失量法-硝酸-氢氟酸消解体系消解的更为彻底,且加酸量少、干扰小,测试结果稳定,因此该方法适宜于对大批量有机物含量偏高的样品进行消解。  相似文献   
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