• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.335-345
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• 2015

This study assessed the changes in Korea's industrial structure to analyze the linkage between years 1995-2000 -2005-2009 Industry Input-Output Tables to access the constant changes in the structure of the inter-industry linkage analysis. First, the Korean economy during the period of analysis was based on solid growth from 1,190 trillion won in 1995 to 2,775 trillion won in 2009. Second, the structure of the industry association in the case of industries, services and electronic form was as follows: in 1995, Heavy-heavy-primary, public; in 2000, service-heavy-heavy, electronic-primary, public; in 2005 Services - Manufacturing - Consumer Goods - first, public, service; and 2009 e-manufacturing - Consumer Goods - primary, the public.

• Journal of Electrical Engineering and Technology
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• v.2 no.4
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• pp.468-477
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• 2007

The DTC of voltage source inverter-fed PMSMs is based on hysteresis controllers of torque and flux. It has several advantages, namely, elimination of the mandatory rotor position sensor, less computation time, and rapid torque response. In addition, the stator resistance is the only parameter, which should be known, and no reference frame transformation is required. The DTC theory has achieved great success in the control of induction motors. However, for the control of PMSM drives proposed a few years ago, there are many basic theoretical problems that must be clarified. This paper describes an investigation into the effect of the zero voltage space vectors in the DTC system and points out that if using it rationally, not only can the DTC of the PMSM drive be driven successfully, but torque and flux ripples are reduced and overall performance of the system is improved. The implementation of DTC in PMSM drives is described and the switching tables specific for an interior PMSM are derived. The conventional eight voltage-vector switching table, which is namely used in the DTC of induction motors does not seem to regulate the torque and stator flux in a PMSM well when the motor operates at low speed. Modelling and simulation studies have both revealed that a six voltage-vector switching table is more appropriate for PMSM drives at low speed. In addition, the sources of difficulties, namely, the error in the detection of the initial rotor position, the variation of stator resistance, and the offsets in measurements are analysed and discussed.

• Journal of Korean Society of Transportation
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• v.26 no.2
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• pp.109-119
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• 2008

The number of card users has grown steadily after the adaption of smart card. Considering the diverse information from smart card data, the increase of card usage rate leads to various useful implications meaning in travel pattern analysis and transportation policy. One of the most important implications is the possibility that the data enables us to generate transit O/D tables easily. In the case of generating transit O/D tables from smart card data, it is necessary to filter data error and/or data missing. Also, the correction of data missing is an important procedure. In this study, it is examined to compute the level of data error and data missing, and to correct data missing for transit O/D generation.

• Journal of Korean Society of Transportation
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• v.30 no.4
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• pp.33-42
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• 2012

Recent development and penetrating expansion in ICT(Information and Communication Technology) has brought considerable improvements in transportation services. However, there is a controversial debate whether transportation and communications behave as substitutes or as complements to one another. On this subject, recent studies considered those two industries as services, but transportation and communications are broadly put for intermediary goods into other industries. Hence, it is essential to examine this issue from understanding their relationships to each other with respect to manufacturing and services. In this study, input-output tables of benchmark years from 1980 to 2005 have been analysed to explore the relationships between transportation and communications using Spearman's correlation analysis. The results show that both industries had complementary roles over the period, but, to some extent, changed into substitution roles in some categories.

• Journal of the Korean Society of Food Culture
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• v.6 no.4
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• pp.403-411
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• 1991

A survey was made, from May to June 1991, to reveal the current situation of the meal management of the homemakers in Jeonbuk area. The results obtained from 464 homemakers were summerized as follows. The meal expenses were planned and managed mostly by the homemakers (93.3%). The 31.1% homemakers expended 200,000-300,000 Won a month for meals and the average expenditure was 294,106 Won. Among the homemakers who responded, the 34.0% managed their account books for meal expenses. With decreasing age(p<0.05), increasing education level (p<0.001), and increasing the income(p<0.01), the number of those who managed the account book tended to be higher. Usually they bought their foods at the market place (52.1%) and they did every other days(33.2%). The 46.9% planned what to buy and chose the best ones among the foods they planned to buy at the market. The percentage of those who prepared their menus planned in advance was only 5.5%. The most homemakers cooked for themselves (96.8%). On cooking and buying foods, the 48.2% considered their husbands first and the 64.4% regarded the tastes and needs of their families as the most important thing. The majority (66.2%) regarded the dinner as the most important among those three times of meals. The 39.6% prepared Kimchi twice a month. The foods they prepared for each meal were usually 4-5 kinds (43.2%). Mostly they prepared meals three times a day (49.1%). The average times spent in preparing and cleaning the tables for lunch and breakfast were 41.6, 96.2 minutes respectively. The homemakers who had jobs tended to spend less time in preparing and clearing the tables than those who had not (p<0.01, p<0.001). The 58.0% had complaints in that the food prices were too high and their moneys for meal preparation were insufficient and the 16.6% had difficulty in satisfying the tastes of their families.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.7
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• pp.2599-2613
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• 2015

Multi-index hashing (MIH) is the state-of-the-art method for indexing binary codes, as it di-vides long codes into substrings and builds multiple hash tables. However, MIH is based on the dataset codes uniform distribution assumption, and will lose efficiency in dealing with non-uniformly distributed codes. Besides, there are lots of results sharing the same Hamming distance to a query, which makes the distance measure ambiguous. In this paper, we propose a data-oriented multi-index hashing method (DOMIH). We first compute the covariance ma-trix of bits and learn adaptive projection vector for each binary substring. Instead of using substrings as direct indices into hash tables, we project them with corresponding projection vectors to generate new indices. With adaptive projection, the indices in each hash table are near uniformly distributed. Then with covariance matrix, we propose a ranking method for the binary codes. By assigning different bit-level weights to different bits, the returned bina-ry codes are ranked at a finer-grained binary code level. Experiments conducted on reference large scale datasets show that compared to MIH the time performance of DOMIH can be improved by 36.9%-87.4%, and the search accuracy can be improved by 22.2%. To pinpoint the potential of DOMIH, we further use near-duplicate image retrieval as examples to show the applications and the good performance of our method.

• Journal of Korean Library and Information Science Society
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• v.36 no.1
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• pp.353-370
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• 2005

The purpose of this study aims to provide possible suggestions for the improvement of the korean Decimal Classification System in 21th century through the analysis of history field as the subject of study. As a result of this study, some problems(for example, irrational classification number system, very simplicity of $\lceil$Table of Geographic Areas. Historical Periods. Persons$\rfloor$. improper development of class 900, necessity of some internal tables and $\lceil$Table of Racial, Ethnic, National Groups$\rfloor$, insufficiency of note etc.) were found out. This study can be useful for the future revision of KDC4 because a revolutionary improvement were provided.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.9
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• pp.1335-1344
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• 2015

A set of prediction equations to estimate the nitrogen-corrected apparent metabolizable energy (AMEn) of individual ingredients and diets used in the poultry feed industry was evaluated. The AMEn values of three energy ingredients (maize, sorghum and defatted maize germ meal), four protein ingredients (soybean meal, maize gluten meal 60% crude protein, integral micronized soy and roasted whole soybean) and four diets (three containing four feedstuffs, complex diets, and one containing only corn-soybean meal, basal diet) were determined using a metabolism assay with male broilers from 1 to 7, 8 to 21, 22 to 35, and 36 to 42 days old. These values were compared to the AMEn values presented in the tables of energy composition or estimated by equation predictions based on chemical composition data of feedstuffs. In general, the equation predictions more precisely estimated the AMEn of feedstuffs when compared to the tables of energy composition. The equation AMEn (dry matter [DM] basis) = 4,164.187+51.006 ether extract (% in DM basis)-197.663 ash-35.689 crude fiber (% in DM basis)-20.593 neutral detergent fiber (% in DM basis) ($R^2=0.75$) was the most applicable for the prediction of the energy values of feedstuffs and diets used in the poultry feed industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.1
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• pp.25-31
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• 2009

The anti-vibration tables that use air suspensions as dampers have been widely used due to their high anti-vibration performance in wide frequency band. However, they face a problem of easily accelerating the vibration when triggered by external force because their air suspensions have low rigidity and dampness. In response, there has been a study on active/semi-active dampers that use only the passive components like air suspensions to complement the passive-control format. Thus, we have dynamically analyzed the active/semi-active control of such passive anti-vibration tables. To demonstrate the anti-vibration table's control system, we have also constructed a kinetic model based on the physical characteristics of an anti-vibration table with 6 degrees of freedom and verified its applicability through analysis and experiments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12B
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• pp.1037-1043
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• 2006

There has been proposed an algorithm to reduce data burst processing delay in group scheduling in core nodes of optical burst switching networks. Since, in this algorithm, look-up tables containing all the void time information in scheduling windows are generated as soon as the primary group scheduling session terminates, it becomes faster to reassign dropped data bursts to proper voids in different data channels by referring to the tables. The group scheduling with this algorithm showed almost the same channel utilization as the one without using the algorithm but performed a little better in both burst loss probability and wavelength conversion rate. On the other hand, per-burst processing time has been reduced dramatically in the load region of higher than 0.8, showing a factor of 2.1 reduction at 0.9.