• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.27-34
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• 2003

Present combustion engines have reached almost at the limit of development due to the fundamental structural problems. This study was carried out to propose a new concept internal combustion engine which has great potential advantages to the conventional engines. Proposed new concept engine is a kind of rotary engine. A rotor is rotating concentrically in a cylinder which is divided into two partitioning valves. and it makes four compartments in the cylinder. The volumes of each of four compartments are changing continuously with the rotor movement, and performs the functions of intake, compression. expansion and exhaust simultaneously. The results of this study can be summarized as follows. 1. Expected theoretical thermal efficiency is 44.9 percent at the condition of 1000rpm and compression ratio of 8.0. which is almost the same as that of the conventional engines. i.e., piston and Wankel rotary engine. 2. The new concept engine has 2. working strokes in every revolution. Therefore. the new concept engine can reduce the specific weight and volume than four-stroke piston engine. 3. The torque variation is very small. therefore minimal noise and vibration are expectable. 4. The new concept engine can reduce mechanical energy loss than piston engine because neither crank mechanism nor eccentrical motion exists.

• Journal of the Korean association of regional geographers
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• v.9 no.3
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• pp.248-261
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• 2003

Through a qualitative analysis of the Ikuno Korean Festival in Osaka, this article examines and critiques how identities are constructed, and how this process is shaped by the mediation of intra and inter-community concerns. Particular attention is paid to the potential of reorganized culture through a thinking of similarity rather than difference. The dynamic interrelations suggest that festival provides a particular and informal public sphere wherein certain social logics and identities are contested. These discursive arenas are therefore marked by certain exclusions and inclusions. This study shows the complex process of identification at the micro-level through which identification is constituted and continuously negotiated.

• Journal of the Korean Society of Safety
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• v.20 no.1 s.69
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• pp.107-112
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• 2005

The purpose of this study is to propose and introduce Accidents Prevention Remedies(APRs) and their priorities especially for Accident Causing factors(ACFs) drawn by surveying and analyzing how much foreign workers in Korea have been exposed to dangers at a construction site. At frist as a result of the analysis of the questionnaire which 59 foreign industrial trainees working at the construction sites in Seoul-Kyunggi area had responsed, 12 ACFs and 11 APRs were put out by using the SPSS programme. Then, through the Analytic Hierarchy Process(AHP) about the questionnaire from 96 safety and civil engineers who have experienced in managing foreign labor at the construction sites all over the country, the APRs given their priorities of relative importances are as follows; First, it is absolutely necessary that every working order to foreign workers should be made more definitely in accordance with a concrete process schedule. Second, the owners should increase investments in improving foreign workers' welfare in order to minimize their potential human error. Third, Korean language education programme for simple technical terms should be made and executed at least.

• Analytical Science and Technology
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• v.6 no.1
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• pp.83-92
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• 1993

The electrochemical behaviors of lanthanide ion(La and Nd) and lanthanide complexes with 2, 2, 6, 6-tetramethyl-3, 5-heptanedione(THD), sym-hydroxydibenzo-16-crown-5(HD16C5) and sym-dibenzo-16-crown-5-oxyacetic acid(D16C5A) ligands in acton solution have been investigated by the use of cyclic voltammetry and direct current polarography. The peak potential and peak current, their dependency on the concentration, temperature, the reversibility of the eleotrode reactions are described. The reduction of the lanthanide ions and complexes in 0.05 M TEAP proceeded one-electron step in first step and one two-electron step in second step. These reduction step was irreversible and the reduction current was diffusion controlled. Macrovcyclic crown ethers, sym-hydroxydibenzo-16-crown-5(HD16C5) and sym-dibenzo-16-crown-5-oxyacetic acid(D16C5A), were prepared from 1, 5-bis-(2-hydroxyphenoxy)-3-oxapentane with epichlorohydrin. The voltammetric behaviors of Ln(III)-HD16C5 and Ln-D16C5A complexes in aceton solution have been investigated by the voltammetric method. The composition and stability constants of lanthanide complexes were determined.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.11
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• pp.3775-3788
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• 2014

With the increasing number of the wireless and mobile networks, the way that people use the Internet has changed substantively. Wireless multimedia services, such as wireless video streaming, mobile video game, and mobile voice over IP, will become the main applications of the future wireless Internet. To accommodate the growing volume of wireless data traffic and multimedia services, cognitive radio (CR) and Information-Centric Network (ICN) have been proposed to maximize the utilization of wireless spectrum and improve the network performance. Although CR and ICN have high potential significance for the future wireless Internet, few studies have been conducted on collaborative operations of CR and ICN. Due to the lack of infrastructure support in multi-hop ad hoc CR networks, the problem is more challenging for video streaming services. In this paper, we propose a Cross-layer Video Streaming Mechanism (CLISM) for Cognitive Radio Ad Hoc Information Centric Networks (CRAH-ICNs). The CLISM included two distributed schemes which are designed for the forwarding nodes and receiving nodes in CRAH-ICNs. With the cross-layer approach, the CLISM is able to self-adapt the variation of the link conditions without the central network controller. Experimental results demonstrate that the proposed CLISM efficiently adjust video transmission policy under various network conditions.

• Journal of the Korean Society of Food Culture
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• v.30 no.4
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• pp.413-421
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• 2015

A travel destination offers a form of novelty to the traveler since it can provide experiences that are not of the everyday variety. Therefore, a search for novelty is important as a motivation factor when planning leisure trips and vacation activities and to identify travel market segments. This study aimed to examine the differences in demographic characteristics, travel style, and preferred food-related activities in accordance with the level of tourists' novelty seeking. This study investigated potential tourists using a self-administered questionnaire survey, which resulted in 300 usable questionnaires. The respondents of this study were classified into two groups according to their level of novelty seeking: Active novelty-seeking group and Passive novelty-seeking group. These two groups were significantly different with respect to demographic characteristics, travel style, and preference of food-related-activity experience. The results show that the Active novelty-seeking group tended to have a higher proportion of females and specialized jobs, a higher level of monthly income and education, more frequent travel, and preference for food-related activity experience than other groups. The result of this study will be helpful for the tourist industry, which needs to develop culinary and food-related experience tour programs and travel market segments.

• Journal of Families and Better Life
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• v.21 no.3
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• pp.123-131
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• 2003

The potential of information and communication technologies has already had a profound impact on many ways of our living and society. To catch up with this trend, Korean government has demonstrated the vision for informatization called‘Cyber Korea 21'/'e-Korea’project and has fully supported the education for informatization which is one of the key factors to reduce the digital divide. But, In spite of developing a variety of training programs with different target groups and policy objectives, a digital divide remains in some cases even while Internet access and computer ownership are rising rapidly for almost all groups. For example, the noticeable divides still exists between men and women. To accelerate the process of women informatization, which we believe to be major contributors for the high quality of life for women, we need to promote full-time housewives to become aggressive information users and producers. Internet shopping, for example, might be a good starting point for motivating women to become active information users. In this paper, we present a model for explaining the factors affecting the degree of satisfaction of housewives from internet shopping. Based on data collected from a questionnaire survey from housewives in Seoul, we conclude that the perceived usefulness, ease of use and the playfulness significantly affect the level of satisfaction, but the playfulness does not directly affect the intention to revisit and purchase. In addition, we found out that the perceived usefulness is affected by efficiency, attitude and easy to access. We also provide other interesting statistical results and implications.

• Journal of the Korean Home Economics Association
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• v.45 no.2
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• pp.77-90
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• 2007

Using 2004 Household Income & Expenditure Survey, this study investigated difference in consumption pattern among the households with the different number of children, and estimated the monetary cost of rearing children. The findings were as following. First, the major consumption categories for raising children included the expenditures for education, food materials, utility, health, and communication. Second, the potential consumption needs for clothing & foot ware and culture & entertainment were not fully satisfied for the households with children compared to the households without children. Third, in the households with one child, the level of consumption was about two thirds of that in the households without children. It was slightly above half in the households with two children. Lower consumption level of the households with children was mainly due to the burden of the educational expenditure. Forth, the average monthly cost of raising children was estimated by 680 thousands Won for one child, and 104 thousand Won for two children. Lastly, the implications for the fertility policy and the methods for the estimation of the child cost were suggested based on the results.

• Journal of the Korean Institute of Educational Facilities
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• v.13 no.1
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• pp.5-16
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• 2006

The study is intended to analyze the tendency of the remodeling for the middle schools in Gyeonggi Province, with the potential challenges thereof, thereby determining the principle for the remodeling projects in the days to come. To that end, the analysis to identify the school facilities in a bid to accommodate the current curriculum was conducted, along with the case study on remodeling projects. The $7^{th}$ curriculum demands for a significant change in school facilities. The number of student in a class that has been on the decline, despite of steady increase in number of schools, and the population getting concentrated in Seoul and its suburbs have resulted in an increase in number of class. Consequently, more investment in the facility, rather than improving a substantial education environment, has been made. The study, thus, is aimed at identifying the facility of the middle school required by the $7^{th}$ curriculum, as well as implementing a fact-finding investigation into the remodeling works for middle schools in Gyeonggi Province so as to come up with the guideline for remodeling projects.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3385-3390
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• 2010

$Li^+$ ion complex of azacrown ether with restricted motion of freedom and pseudo-bilateral symmetry was studied by infrared spectroscopy, which has shown simplified and broadened vibrational features. The C=O and N-H stretching bands, in particular, shows anomalous broadening nearly ${\sim}50\;cm^{-1}$. The density functional calculation at the level of BP86/6-31+$G^{**}$ shows that $Li^+$ ion is trapped and rather free to move around inside the cavity, as much as about $0.70\;{\AA}$. Through the relocation of $Li^+$ ion inside the cavity, the conformational changes would occur rapidly in its symmetry $C_1\;{\rightleftarrows}\;C_2\;{\rightleftarrows}\;C_1$$. The potential barrier was obtained to be merely ~2.2 kJ/mol for $C_1\;{\rightarrow}\;C_2$. During this conformational alteration, the amide backbone twists concurrently its dihedral angle side to side about up to ${\pm}3$ degree. Selected vibrational modes were interpreted in terms of the force constant variations of local symmetry coordinates between conformations in the framework of $C_1\;{\rightleftarrows}\;C_2\;{\rightleftarrows}\;C_1$.