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排序方式: 共有173条查询结果,搜索用时 31 毫秒
51.
提出一种基于逐行扫描算法改进的光纤束起点位置搜索方法。在图像采集阶段,由于手动放置CCD很难与光纤束出端完全平行,导致采集到的光纤束图像出现倾角,利用最小二乘法和双线性差值方法校正图像。在光纤束起点位置获取阶段,针对传统’Z’字型搜索算法存在的问题,采取每行只搜索横坐标小于一行像素数1/3的方法。实验结果表明该法避免了搜索错误,同时保证了搜索高效率。 相似文献
52.
Anne Lise Tang Gisela Wilcox Karen Z. Walker Nagandra P. Shah John F. Ashton Lily Stojanovska 《Journal of food science》2010,75(6):M373-M376
Abstract: The presence of phytate in calcium-fortified soymilk may interfere with mineral absorption. Certain lactic acid bacteria (LAB) produce the enzyme phytase that degrades phytates and therefore may potentially improve mineral bioavailability and absorption. This study investigates the phytase activity and phytate degradation potential of 7 strains of LAB including: Lactobacillus acidophilus ATCC4962, ATCC33200, ATCC4356, ATCC4161, L. casei ASCC290, L. plantarum ASCC276, and L. fermentum VRI-003. Activity of these bacteria was examined both in screening media and in calcium-fortified soymilk supplemented with potassium phytate. Most strains produced phytase under both conditions with L. acidophilus ATCC4161 showing the highest activity. Phytase activity in fortified soymilk fermented with L. acidophilus ATCC4962 and L. acidophilus ATCC4161 increased by 85% and 91%, respectively, between 12 h and 24 h of fermentation. All strains expressed peak phytase activity at approximately pH 5. However, no phytate degradation could be observed. 相似文献
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54.
Developing a well-designed market survey questionnaire will ensure that surveyors get the information they need about the target market. Traditional sampling survey via questionnaire, which rates item by linguistic variables, possesses the vague nature. It has difficulty in reflecting interviewee’s incomplete and uncertain thought. Therefore, if we can use fuzzy sense to express the degree of interviewee’s feelings based on his own concept, the sampling result will be closer to interviewee’s real thought. In this study, we propose the fuzzy sense on sampling survey to do aggregated assessment analysis. The proposed fuzzy assessment method on sampling survey analysis is easily to assess the sampling survey and evaluate the aggregative evaluation. 相似文献
55.
ContextLearning can be regarded as knowledge construction in which prior knowledge and experience serve as basis for the learners to expand their knowledge base. Such a process of knowledge construction has to take place continuously in order to enhance the learners’ competence in a competitive working environment. As the information consumers, the individual users demand personalised information provision which meets their own specific purposes, goals, and expectations.ObjectivesThe current methods in requirements engineering are capable of modelling the common user’s behaviour in the domain of knowledge construction. The users’ requirements can be represented as a case in the defined structure which can be reasoned to enable the requirements analysis. Such analysis needs to be enhanced so that personalised information provision can be tackled and modelled. However, there is a lack of suitable modelling methods to achieve this end. This paper presents a new ontological method for capturing individual user’s requirements and transforming the requirements onto personalised information provision specifications. Hence the right information can be provided to the right user for the right purpose.MethodAn experiment was conducted based on the qualitative method. A medium size of group of users participated to validate the method and its techniques, i.e. articulates, maps, configures, and learning content. The results were used as the feedback for the improvement.ResultThe research work has produced an ontology model with a set of techniques which support the functions for profiling user’s requirements, reasoning requirements patterns, generating workflow from norms, and formulating information provision specifications.ConclusionThe current requirements engineering approaches provide the methodical capability for developing solutions. Our research outcome, i.e. the ontology model with the techniques, can further enhance the RE approaches for modelling the individual user’s needs and discovering the user’s requirements. 相似文献
56.
Jordan lacks companies that provide local medical facilities with products that are of help in daily performed medical procedures. Because of this, the country imports most of these expensive products. Consequently, a local interest in producing such products has emerged and resulted in serious research efforts in this area. The main goal of this paper is to provide local (the north of Jordan) clinics with a computer-aided electrocardiogram (ECG) diagnostic tool in an attempt to reduce time and work demands for busy physicians especially in areas where only one general medicine doctor is employed and a bulk of cases are to be diagnosed. The tool was designed to help in detecting heart defects such as arrhythmias and heart blocks using ECG signal analysis depending on the time-domain representation, the frequency-domain spectrum, and the relationship between them. The application studied here represents a state of the art ECG diagnostic tool that was designed, implemented, and tested in Jordan to serve wide spectrum of population who are from poor families. The results of applying the tool on randomly selected representative sample showed about 99% matching with those results obtained at specialized medical facilities. Costs, ease of interface, and accuracy indicated the usefulness of the tool and its use as an assisting diagnostic tool. 相似文献
57.
Abstract. Information systems are organizations in which signs are created, processed and consumed. In order to fulfil the organizational goals and objectives, its members must understand their responsibilities and authorities, and must act co-operatively. The key to this organization and co-ordination lies in norms, which define responsibilities and authorities for each human agent, and establish regularities of behaviour. In the context of co-operative work, where 'intelligent' software agents are involved, to understand the norms of behaviour of various human agents becomes critical. Software agents can perform some tasks autonomously on the user's behalf. Such delegation involves a set of complicated philosophical and legal issues. After discussion on delineation of various boundaries of responsibility and authorities, this paper addresses norms and normative behaviour of human agents within an organization. It discusses the taxonomies of norms and a method of norm specification, with examples. Finally it presents an approach of norm-based agency for designing collaborative information systems and a case study of an insurance claim for illustration. 相似文献
58.
Although administrators of online communities (OCs) may focus on improving their OCs through upgrading technology and enhancing the usability of their OCs to attract additional users, the level of OC participation may be associated with social motives. The purpose of this study is to understand how social motivations (that is, network externalities and social norms) affect members committed to OCs. This study tests the hypotheses on data collected from 396 undergraduate students. Data analyses show that network externalities and social norms directly influence social interaction ties, which subsequently results in commitment toward a community. Social norms also directly influence relationship commitments to a community. The results provide insights into how social motivations lead to commitment to an OC, reminding OC administrators to encourage member commitment to the OC from the perspective of social motivations. 相似文献
59.
乙烯裂解原料的优化,已经成为石油化工行业中非常重要的一环。我国裂解制乙烯的原料,主要以石脑油为主。石脑油的二次加工油品拔头油以其优良的裂解特性,如芳烃含量较少、结焦少、三烯产量较高等优点,越来越引起众多乙烯制造者以及研究者的注意。本文研究拔头油的组成、性质和裂解特性时,发现拔头油的馏程窄,用恩氏蒸馏数据计算其他性质,但精度较低,于是提出计算拔头油性质的“替代算法”,并利用裂解模拟软件PYRO-SimP模拟和分析生产中拔头油在毫秒炉中的裂解过程,结果表明这种算法效果很好。 相似文献
60.
企业内部缺乏CIO人选或继任者,常常促使其求助于猎头公司;当企业希望CIO能够推动领导层、战略和文化的革新与变革时,通常倾向于从外面寻找候选人;传统的职位描述通常过于战术化、太强调任务,而对于人选的个性特征和职位预期绩效的描述并不多。以上是Gartner一项调查的关键结果。挑选诸如CIO这种新任高管是一个至关重要的决定,它将对企业的战略发展、运营和财务绩效产生重要影响。 相似文献