• Journal of the Korean Society for Railway
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• v.17 no.6
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• pp.433-442
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• 2014

This paper evaluates the performance of transit assignment algorithms for urban rail networks. The accuracy of the algorithms is essential not just for travel forecasting but also for the area of applications such as the assessment of road vulnerability and the fare adjustments between train operating companies. Nonetheless, the suitability and caveats for the series of computational steps have not yet been much discussed. This study thus considers the characteristics that are appropriate for investigating Seoul rail travelers using three representative transit assignment algorithms: the optimal strategy algorithm, route choice algorithms, and the Dial's algorithm. Both the theoretical foundation and the empirical performance are examined. The results demonstrate that the Dial's algorithm is superior in terms of the theoretical soundness and the computational efficiency.

• Journal of Navigation and Port Research
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• v.36 no.1
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• pp.69-74
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• 2012

Recent global supply chain, improving the efficiency of container shipping process is very important. In the overseas shipping of goods, the voyage of super containership is common to overcome amount of increasing cargo. Thus, container terminal managers make an experiment on the double cycle and dual cycle operation, which ship loading and unloading were carried out simultaneously, for maximizing the productivity of quay side. Yard Tractors(YTs) pooling methods also are introduced for increasing the efficiency of assignment of YTs. In this paper, we analyzed the efficiency of dual cycling through comparing existing pooling methods with the modified method for the dual cycling. We developed a simulation model using simulation analysis software, Arena. The result of experiment shown that the more dual cycling don't always increase the gross crane rate(GCR), which means productivity of quay cranes(QCs) per hour.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.4
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• pp.370-379
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• 2014

Recently, the interest in optical network with multifiber link is continuing to rise since the network traffic has been growing exponentially. However, growing traffic in network leads to increasing the energy consumption of the network equipment. In this paper, we propose a dynamic routing and wavelength assignment (RWA) algorithm based on V-like cost function and layered graph to improve energy efficiency in IP over WDM network with multifiber link. The V-like cost function is used to decide the fiber cost according to the number of used wavelengths. The layered graph with multifiber link is used to select the energy efficient route and wavelength. The proposed RWA algorithm is compared and analyzed with conventional algorithm in view of average power consumption and blocking probability through OPNET modeler.

• BMB Reports
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• v.28 no.5
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• pp.433-436
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• 1995

In order to assign NMR signals, conditions for the specific labeling of cytochrome $c_3$ of D. vulgaris Miyazaki F through the culture in a minimal medium were established. Phenylalanine residue was specifically deuterated at more than 85% efficiency. Cytochrome $c_3$ has two phenylalanine residues. The signals of one phenylalane were missing and this was tentatively assigned to Phe20.

• Journal of Korea Technology Innovation Society
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• v.3 no.3
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• pp.53-66
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• 2000

This study analyses the actual conditions and efficiency of supplier relations of If equipment industries of Korea. The fact-finding survey we conducted includes PCs, mobile phone handsets, and public switching equipments. The survey shows that there is room for improvement in the aspect of assignment of roles among suppliers in R&D activities.

• Journal of Korean Library and Information Science Society
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• v.30 no.3
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• pp.27-51
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• 1999

This paper deals with the methods as well as the problems associated with automatic extraction indexing and assignment indexing, expert systems for indexing, and major approaches currently used to index the Internet resources. It also briefly reviews basic methods for establishing hypertext/hypermedia links automatically. The methods used in much of text processing today are not particularly new. Most of the them were used, perhaps in a more rudimentary form, 30 or more years ago by Luhn and many other investigators. Better results can be achieved today because much greater bodies of electronic text are now avaliable and the power of present-day computers allows the processing of such text with reasonable efficiency.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.4
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• pp.1008-1018
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• 1996

For assigning channel in a cellular sireless network, we purpose satisfying constraints with a related probability between cells and channels on the channel interference matrix formed by m terminals and n channels. And we purpose to get efficient channel assigning to limited channels in a wireless cell using parallelism of neural networks. In this paper, we solve the problem according to the number of requeirements when channel change with 11-533 procession elements. We demonstrate efficiency of proposed algorithm through same simulations in a specific time period.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.802-807
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• 2005

For linear projects, it has long been known that resource utilization is important in improving work efficiency. However, most existing scheduling techniques cannot satisfy the need for solving such issues. This paper presents an optimization model for solving linear scheduling problems involving resource assignment tasks. The proposed model adopts constraint programming (CP) as the searching algorithm for model formulation, and the proposed model is designed to optimize project total cost. Additionally, the concept of outsourcing resources is introduced here to improve project performance.

• Journal of Families and Better Life
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• v.6 no.1
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• pp.189-203
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• 1988

The main objective of this dissertation is to find out the measurement methods of household work organization and manger style and the quantitative analysis methods of influential factors on household work organization and manager style. Subjects were homemakers living in metropolitan , medium and small cities. Questionnaires were sent to subjects and usable responses were 1139 out of 1239 received questionnaires. Data collected through both preliminary and main survey were analyzed by using frequencies, percentage, analysis of variance, chi-square test and pearson's correlation analysis. Results are as follows; 1) The degree of household work organization was distributed on upper middle level exceeding middle score. Among subsystems of household work such as task assignment , test regularization, task arrangement and task standardization. subjects show the highest positive attitude in task standardization. 2) The characteristics of management in household work have task centered orientation. By the prority of task centered orientation, the order was integrated style. dedicated style. It means that the most ideal style is an integrated style which accounts for one-third of the total homemakers. 3) Household organization's subsystems and household work manager style are related with socio-demographic variables. Integrated style is significantly related with homemaker's employment and having helpers for household work. homemakers who are employed and have helpers for household work exhibit high scores in task assignment and task arrangement. Dedicated style is significantly related with homemaker's age and the number of children. Homemakers who are older and have many children exhibit high scores in task assignment. Related style is significantly related with marriage duration, education level and income level. Homemakers who have a long marriage duration exhibit high scores in task assignment and who have high education and income level exhibit high scores in task regularization. Seperates style is significantly related with homemaker's age m marriage duration an family life cycle. homemakers who ar older, have a long marriage duration and are of late stage in family life cycle exhibit seperated style and high scores in organization. To summarize research findings, household work manger and household work organization are related with family life experiences, and task assignment is an influential variable on manager style. in conclusion, it is evident that household work organization emphasizes efficiency as cognitive component and such organization. Finally it is necessary to broaden this research considered social psychological variables. And also it needs to build household manger style models appropriate fro the characteristics of each style.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.6
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• pp.1463-1479
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• 2013

In this paper, we propose an unequal protection physical coding sub-layer (PCS) forward error correction (FEC) scheme for efficient and high-quality transmission of video data over optical access networks. Through identifying and resolving the unequal importance of different video frames and passing this importance information from MAC-layer to PCS, FEC scheme of PCS can be adaptive to application-layer data. Meanwhile, we jointly consider the different channel situations of optical network unit (ONU) and improve the efficiency of FEC redundancy by channel adaptation. We develop a theoretical algorithm and a hardware method to achieve efficient FEC assignment for the proposed unequal protection scheme. The theoretical FEC assignment algorithm is to obtain the optimal FEC redundancy allocation vector that results in the optimum performance index, namely frame error rate, based on the identified differential importance and channel situations. The hardware method aims at providing a realistic technical path with negligible hardware cost increment compared with the traditional FEC scheme. From the simulation results, the proposed Channel and Application-layer data Adaptation Unequal Protection (CAAUP) FEC scheme along with the FEC ratio assignment algorithm and the hardware method illustrates the ability of efficient and high-quality transmission of video data against the random errors in the channel of optical access networks.