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11.
身份构建是石油学术语篇中体现作者在该领域贡献的重要方式。为了解英语学术语篇中作者身份的构建手段及其语用功能,收集了SPE(石油工程师协会)英语论文50篇,采用Wordsmith5.0进行检索,研究国外学者如何在石油学术语篇中建构其作者身份,并以“面子保全”理论分析其语用功能。结果表明,第一人称复数各种形式是最重要的建构手段,在不同语境中实现不同语用功能;第三人称抽象名词在建构中占据重要地位,实现了与人称代词不同的语用功能;介词短语也是建构手段之一,同样体现了作者的主体地位。  相似文献   
12.
《易传》除《杂卦》而外,均成书于孟子、荀子之后,司马迁之前,其成书的先后顺序应该是:《系辞》、《文言》、《彖传》、《象传》、《序卦》、《说卦》、《杂卦》。作者除《说卦》为汉初方士儒,《杂卦》为汉武帝以后的汉儒所作外,其他基本上是战国末至秦、汉初的子夏后学所作。《易传》的出现体现了百家争鸣以来,儒家"以神道设教"构建儒家化形上学的努力。  相似文献   
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以信息、语言、记忆工业和时间物体为代表的后现代技术,批判现代技术的机械化、商品化、功利化、权力化人类中心主义以及物化和异化带来的各类难以预测的事故和灾难。主张在非祛魅性、多元性、生态性和非决定论的后现代科学基础上,根除"技术官僚主义",推动后现代技术往更加人道、民主、自由、智慧和艺术的方向发展,将技术进一步人性化和真善美一体化,使其真正为新人民和全人类的文明服务。  相似文献   
15.
旅行承办人违约造成旅客非财产性损害(包括固有利益和非财产性的利益损害),旅客能否要求违约方承担以及承担什么样的赔偿责任是许多国家立法、判例和学说所不能回避的问题。从各旅行大国的学说、判例的比较分析中,结合我国现有法律规定和实践中的做法,为其赔偿制订正当性的理论和实证法上的说明,以期对我国旅游合同纠纷的解决有所裨益。  相似文献   
16.
Lack of data on daily inhalation rate and activity of children has been an issue in health risk assessment of air pollutants. This study aimed to obtain the daily inhalation rate and intensity and frequency of physical activity in relation to the environment in Japanese preschool children. Children aged four–six years (n= 138) in the suburbs of Tokyo participated in this study, which involved three days' continuous monitoring of physical activity using a tri‐axial accelerometer and parent's completion of a time/location diary during daily life. The estimated three‐day mean daily inhalation rate (body temperature, pressure, saturated with water vapor) was 9.9 ± 1.6 m3/day (0.52 ± 0.09 m3/kg/day). The current daily inhalation rate value of 0.580 m3/kg/day proposed for use in health risk assessment in Japan is confirmed to be valid to calculate central value of inhaled dose of air pollutants in five‐ to six‐year‐old children. However, the 95th percentile daily inhalation rate of 0.83 m3/kg/day based on measurement for five‐year‐old children is recommended to be used to provide an upper bound estimate of exposure that ensure the protection of all five‐ to six‐year‐old children from the health risk of air pollutants. Children spent the majority of their time in sedentary and light level of physical activity (LPA) when indoors, while 85% of their time when outdoors was spent in LPA and moderate‐to‐vigorous physical activity. The results suggest the need to consider variability of minute respiratory ventilation rate according to the environment for more refined short‐term health risk assessment.  相似文献   
17.
We consider the transport of containers through a fleet of ships. Each ship has a capacity constraint limiting the total number of containers it can carry and each ship visits a given set of ports following a predetermined route. Each container has a release date at its origination port, and a due date at its destination port. A container has a size 1 or size 2; size 1 represents a 1 TEU (20‐foot equivalent unit) and size 2 represents 2 TEUs. The delivery time of a container is defined as the time when the ship that carries the container arrives at its destination port. We consider the problem of minimizing the maximum tardiness over all containers. We consider three scenarios with regard to the routes of the ships, namely, the ships having (i) identical, (ii) nested, and (iii) arbitrary routes. For each scenario, we consider different settings for origination ports, release dates, sizes of containers, and number of ports; we determine the computational complexity of various cases. We also provide a simple heuristic for some cases, with its worst case analysis. Finally, we discuss the relationship of our problems with other scheduling problems that are known to be open.  相似文献   
18.
Firms in service and make‐to‐order manufacturing industries often quote lead times and prices to customers. We define uniform quotation mode (UQM) as the strategy where a firm offers a single lead time and price quotation, and differentiated quotation mode (DQM) is where a firm offers a menu of lead times and prices for customers to choose from. Both modes are followed in practice. Firms should determine which is more profitable. We classify customers into two groups: lead time sensitive (LS) and price sensitive (PS). LS customers value lead time reduction more than PS customers. We develop mathematical models of both quotation modes and analyze them to determine the most profitable mode under specified situations as well as the best lead time and price quotations within each mode. We find that DQM is dominated by UQM whenever PS customers have positive utilities from UQM or LS customers have positive utilities from DQM. Otherwise, which quotation mode is better depends on multiple factors, such as customer characteristics (including lead time reduction valuation and product valuation of a customer, and the proportion of LS customers) and production characteristics (including the desired service level and service or production cost).  相似文献   
19.
In this paper we present a mathematical program and heuristic algorithms to schedule coils for the production operations in a copper (or steel) coil manufacturing industry. The processing facility uses continuous operations for processing (e.g., galvanizing and annealing) while the handling unit is a discrete coil. The ends of coils are “stitched” or welded together to enable continuous processing, and the joint is later sheared off to obtain the processed coils. Processing constraints impose restrictions on the compatibility between a pair of coils that are overcome by introducing a dummy coil called stringer, which is very expensive to a mill. This paper deals with modeling the sequencing/scheduling problem of coils on parallel non-identical machines to minimize stringer utilization. Both computational and practical experiences show the efficiency and effectiveness of the solution approaches. Implementing these methods in an actual coil annealing facility resulted in 65% reduction in stringer utilization.  相似文献   
20.
一类新型批处理机调度问题的理论分析   总被引:1,自引:0,他引:1  
钢卷在冷轧生产中,为了改进其性能,需要在罩式炉进行退火,退火过程由加热、保温和降温三段组成,而这三段处理时间由于工艺上的要求不能归结为一个时间,这与传统批处理机调度有明显的差别.对新型批处理机的总加权完成时间最小化问题建立了非线性整数规划模型,开发了基于动态规划的启发式算法.通过理论分析,获得该算法的误差性能比为3.对于三段中的某一段板卷的处理时间相同的情况,证明了启发式算法的误差性能比是2,而且证明是紧界.对于三段中的某二段板卷的处理时间相同的情况,证明了启发式算法是最优算法.对启发式算法扩展到带有任意段的加工时间的一般情况进行了性能分析.  相似文献   
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