• 대한지역사회영양학회지
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• 제7권1호
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• pp.58-66
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• 2002

The purpose of the study was to develop and evaluate the reliability of a semi-quantitative food frequency questionnaire (SFFQ) intended to measure mainly nutrient intake (energy, protein, fat, calcium and iron) related to growth in pre-schoolers in Korea. Based on foods with up to 90 cumulative percent contribution of the 5 nutrients, we developed a SFFQ for 86 foods. In order to evaluate the reliability of both nutrient and food intakes, caregivers of a sample of 101 children aged 4 to 6 years completed the SFFQ repeatedly at 3 month intervals. There were small differences in the nutrient intakes assessed by the SFFQ ranging from 0.55% to 9.91%. There were no significant differences in nutrient values calculated from the repeat questionnaires, except in the case of niacin and vitamin C. The Pearson correlation coefficients of most of the nutrients ranged form 0.54 to 0.75 (mean = 0.66). When energy intake was adjusted, there was approximately a 0.2 decrease in the correlation coefficient of most nutrients, due to the high correlation of energy intake with other nutrients (r=0.7-0.9). The amount of food intake differed by 0.1 to 66.4% (mean = 17.5%), depending on the food item. Out of 86 foods, 74 foods (86%) showed less than a 30% difference in intake and 30 foods (35%) showed less than a 10% difference. Only 6 (7%) out of the 86 foods presented statistically significant differences in intake. The Spearman correlation coefficients of most food intakes assessed repeatedly by the SFFQ ranged from 0.4 to 0.7. Reproducibility of the nutrient and food intakes found in this study was better or similar to those found in cases of Korean adults. Therefore, the SFFQ developed in the present study can be a useful tool to assess the dietary intake of pre-schoolers in Korea.

• 한국항공우주학회지
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• 제32권7호
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• pp.60-68
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• 2004

고속으로 비행하는 물체가 다른 물체와 충돌하는 경우에는 극히 짧은 시간에 커다란 변형이 일어나게 된다. 고변형률 변형 (high-strain-rate deformation) 에서는 소성변형이 일어나면서 상당한 열을 발생시키고 재료의 온도를 상승시킨다. 온도의 상승은 재료의 동적인 물성에 많은 영향을 미치게 되므로, 변형 시의 온도상승을 예측하는 것은 매우 중요하다. 변형시의 온도상승은 주로 전위(dislocation)의 움직임과 공공(vacancy)으로 인한 재료내의 저장에너지와 밀접한 관계를 갖게되므로, 저장 에너지의 양을 파악하는 것은 매우 중요하다. 고변형률 변형시 전위가 빠르게 움직이면서 평형상태에서의 경우보다 많은 파공공 (excess vacancies) 을 발생시키게 된다. 본 논문에서는 과공공을 포함하는 미시적 재료 모텔을 구성하고 분자동역학 (molecular dynamics, MD) 기법을 사용하여 면십입방격자 (fcc) 구조를 가지는 재료 (구리)에 대한 저장 에너지를 계산하였다.

• 한국정보컨버전스학회:학술대회논문집
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• 한국정보컨버전스학회 2008년도 International conference on information convergence
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• pp.47-52
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• 2008

A radio-frequency identification(RFID) tag is a small, inexpensive microchip that emits an identifier in response to a query from a nearby reader. The price of these tags promises to drop to the range of $0.05 per unit in the next several years, offering a viable and powerful replacement for barcodes. The challenge in providing security for low-cost RFID tags is that they are computationally weak devices, unable to perform even basic symmetric-key cryptographic operations. Security researchers often therefore assume that good privacy protection in RFID tags is unattainable. In this paper, we explore a notion of minimalist cryptography suitable for RFID tags. We consider the type of security obtainable in RFID devices with a small amount of rewritable memory, but very limited computing capability. Our aim is to show that standard cryptography is not necessary as a starting point for improving security of very weak RFID devices. Our contribution is threefold: 1. We propose a new formal security model for authentication and privacy in RFID tags. This model takes into account the natural computational limitations and the likely attack scenarios for RFID tags in real-world settings. It represents a useful divergence from standard cryptographic security modeling, and thus a new view of practical formalization of minimal security requirements for low-cost RFID-tag security. 2. We describe protocol that provably achieves the properties of authentication and privacy in RFID tags in our proposed model, and in a good practical sense. Our proposed protocol involves no computationally intensive cryptographic operations, and relatively little storage. 3. Of particular practical interest, we describe some reduced-functionality variants of our protocol. We show, for instance, how static pseudonyms may considerably enhance security against eavesdropping in low-cost RFID tags. Our most basic static-pseudonym proposals require virtually no increase in existing RFID tag resources.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권3호
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• pp.186-192
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• 2004

Purpose: Human tooth proteins are highly heterogeneous, comprising diverse proteins derived from a number of genes. The attempts to identify protein for activity of tooth matrix proteins have been defied by several factors. First, the amount of proteins within teeth is very small relative to many extracellular matrix proteins of other tissues. Second, the bioassay system is tedious and needed for long time. Therefore we tried to find easy techniques, which increase the product rate, and an assay of small proteins, with which amino acid sequence is possible without additional procedures. Materials and Methods: Total protein were extracted from 300 g enamel removed teeth and 600 g teeth with 4 mol/L guanidine HCl and purified by gel chromatography. Aliquot of proteins was implanted into muscle pouches in Sprague-Dawley rats for bioassay. By SDS-PAGE and membrane blotting, molecular weight of each protein was estimated and a partial amino acid sequence was obtained. Each fraction blotted on the membrane was cut out and inserted in rat ectopic model. Results: In dissociative method, total tooth proteins were obtained 1mg/ml from enamel removed teeth and 3.5 mg/ml from teeth. In SDS-PAGE, four clear bands at the sites corresponding to 66, 40, 20 and 18 kD. Especially The 66 kD band was clearly exhibited. Amino acid sequencing from tooth could be possible using PVDF membrane blotting technique. In amino acid sequencing, 66 kD protein was identified as albumin. Conclusion: Compared with conventional method for extraction of teeth protein and bioassay of proteins, the methods in this study were easy, time-saving and more productive technique. The matured tooth proteins omitting additional procedure of mechanical removal of enamel were simply analyzed using blotted PVDF membrane. This method seems to make a contribution as a technique for bioassay and amino acid sequencing of protein.

• 한국물환경학회지
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• 제30권4호
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• pp.441-451
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• 2014

Streamflow is typically divided into two components that are direct runoff and baseflow, it is required to analyze and estimate behaviors of those two flow components to understand watershed characteristics so that watershed management plan can be effective in pollutant reductions. Since pollutant load behaviors in a stream or river are variable by flow component behaviors, best management practices need to be applied in a watershed based on the pollutant load behaviors varying with flow components. Thus, baseflow behaviors were analyzed separating baseflow from streamflow data collected from fifteen streamflow gaging stations in the 4 major river watersheds which are the Han river, Nakdong river, Guem river, and Yeongsan Somjin river watersheds. Moreover, precipitation trends throughout the 4 River Systems were investigated, thus daily precipitation data were collected from sixty-five locations. The Hank river watershed displayed the largest precipitation (925.2 mm) in summer but the lowest precipitation (71.8 mm) in winter, indicating the watershed has the most fluctuating precipitation characteristic. While the precipitation trends in the Four River Systems varied, a distinct feature in baseflow trends was not found, moreover baseflow percentages to streamflow were typically greater than 50% in the Four River Systems. As shown in this study, it would be expected significant amount of pollutants could be contributed to the stream in the form of baseflow at the watershed.

• 한국축산식품학회지
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• 제33권4호
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• pp.508-514
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• 2013

Taste-active compounds (e.g., amino acids and nucleotides) play an important role in contribution to the gustatoty sensation of food. The current study aimed to examine the differences in taste-active compounds between different beef muscles, breeds and aging periods. We have chosen the longissimus dorsi and semitendinosus muscles of Hanwoo breed and longissimus dorsi muscle of Angus breed for the investigation of the aforementioned compounds. Hanwoo muscles were aged for 7 or 28 d, and Angus samples were aged for 28 d at $4^{\circ}C$. Results revealed that 8 out of the 18 detected free amino acids (FAA) showed significant (p<0.05) differences between the two Hanwoo muscles. Twelve FAAs showed aging effect (p<0.05) in which the amounts of 8 FAAs significantly increased as aging time increased. Inosine 5-monophosphate (IMP), hypoxanthine (Hx) and inosine showed significant (p<0.05) differences between the Hanwoo muscles, aging resulted in an increase in amounts of these nucleotides. Hanwoo beef had significantly (p<0.05) higher total amount of sweet amino acids than the Angus ones in that 15 amino acids showed differences (p<0.05) between the two breeds. Amounts of guanosine 5-monophosphate (GMP) and Hx were significantly higher (p<0.05) for Angus beef. Current study indicated that muscle type, breed and aging period had large variations in free amino acid and nucleotide contents, which may subsequently affect the taste attributes of cooked beef.

• 산경연구논집
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• 제10권7호
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• pp.49-58
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• 2019

Purpose - Previous studies on the influence of appeal types of advertising messages on pro-social behavior have shown inconsistent results. The purpose of this study is to examine whether the appeal type of advertising affects consumer's prosocial behavior. In particular, the authors investigated whether the social exclusion moderates the relationship between the appeal type of advertising and prosocial behavior. Research design, data and Methodology - To verify the hypothesis, two experimental study were conducted. The experimental study was 2(appeal type : self-benefit vs. other-benefit) by 2(social exclusion : being ignored vs. being rejected) between-subject design. Participants were randomly assigned to one of four conditions. The experiment was conducted using a computer. First, the participants was exposed to the advertising image used in the social campaign, and then responded to questions about social behavior. The participants completed the experiment after further responding to the item for manipulation check and demographic measure. The experiment took about 10 minutes in total. Results - In Study 1, a global warming campaign with participation intention variable, other-benefit ads rather than self-benefit ads drive consumers who feel socially rejected to be more willing and likely to participate, but consumers who feel socially ignored are more likely to participate the campaign in self-benefit ad than other-benefit ad. Study 2 replicates the findings, a child poverty relief campaign with an amount-to-donate variable: consumers who feel explicitly rejected allocate more dollars to the charity in response to other-benefit rather than self-benefit ads, but consumers who being ignored are willing to donate more money. Conclusion - This study has theoretical contribution in that it expands existing theories by explaining the existing inconsistent results of the message appeal influence on pro-social behavior through new control variables. In addition, the results have important managerial implications, suggesting marketers should tailor their marketing message to match the consumer situation.

• 수산해양교육연구
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• 제19권2호
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• pp.180-196
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• 2007

This study aims at analyzing the potential of leports-fishing for improving fishing household income. Leports-fishing is a composite concept which is combined with those of leisure, sports and fishing. Korean on-shore resources have also a composite characteristic. The properties of the east, west and south coastal waters are quite different in geography, biology and ecology. There is a array of leports-fishing development potentials of utilizing their characteristics. At present, angling forms a main activity of leports-fishing, but coastal seas would be an emerging space for the public. In order for them to be a ground of fun, enjoyment and festivals, it would be necessary to supply a wide range of activities and facilities including angling, scuba diving, fish barbecue, ecological experience, fishing experience, cruise, and so forth. As seen in the survey results, the participants have strong desire for fun and enjoyment through leports-fishing activities. The proportion of people participating in one or two times a year amounts to 40 percent. Most coastal places visited are close to medium/large cities and two-days leports-fishing/tourism accounts for some 77 percent. However, it turned out that conflicts between leports-fishing participants and fishermen are not serious. The results of expenditure function estimation appear that the elasticity of per capita income is very high with 1.2660 and that there are negative relationships between leports-fishing expenditure and transportation/food/lodging costs. Assuming the annual national economic growth rate of 4 percent, it is anticipated that Korean leports-fishing population will increase to 3.18 million in 2010 and 4.07 million in 2015. Korean leports-fishing market potential in 2015, which is calculated based on per capita expenditure on leports-fishing, appears to amount to 1,400 billion won~1,600 billion won. The contribution of such market potential to the fishing households is expected to be 62.3~74.2 percent(934.5 billion won~111.3 billion won).

• 한국시뮬레이션학회논문지
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• 제16권3호
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• pp.75-87
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• 2007

VoIP 서비스 품질이 개선되고 많은 문제점들이 극복되면서 이에 대한 사용자들의 관심이 높아지고 있다. VoIP는 인스턴트 메시징 서비스 등 사용자들의 편익을 위한 서비스를 제공하고 있지만 비용 및 보안 문제는 사용자들의 이러한 서비스 사용을 주저하게 만들고 있다. 본 논문은 이와 같은 문제 중 하나인 VoIP 스팸 문제를 다루고자 한다. 스팸 콜에서의 음성 메시지 신호 패턴을 고려하여 정상 콜과 Noise가 포함된 정상 콜, 스팸 콜 이 세 가지 음성 모델을 설계하고, 논문에서 제시하는 음성 신호 정보량 기반의 스팸 탐지 알고리즘에 적용해 보았다. 각 모델의 모델링 및 시뮬레이션은 DEVS-$Java^{TM}$를 이용하였다. 본 연구는 스팸 콜 음성 신호를 탐지하기 위한 방법을 제시하고 이를 모델링 및 시뮬레이션 방법론을 통해 검증하는 것에 기여점을 둘 수 있다.

• 대한가정학회지
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• 제30권1호
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• pp.283-309
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• 1992

This study examines work and family life of married women employed in a manufacturing industry. Data were gathered from the use of fact-to-face interview method from a sample of 230 married working women. The major findings of this study can be summarized as follows : (1) With high rates of change of job, most of the respondents remain unstable in their working situation. It was shown that the important factors influencing job satisfaction of married women are women's life cycle, degree of contribution of wife's income toward total family income, and husband's attitude toward wife's empolyment. The degree of job satisfaction is also strongly influenced by labor structural factors such as pay, work environment and fringe benefits. (2) The amount of household labor time was limited by job-related factors rather than by family-related factors, because among these working women employment itself is necessarily for their subsistance. (3) It was shown that wives participated more actively in their marital communications than their husbands. Most of the respondents showed the syncratic type of the decision making patterns, but this results does not necessarily mean wives exercised an equal power with their husbands. The economic factors and the emotional instability of the husband are the ones mostly influencing marital conflicts of the employed women. It was found that the respondents easily revealed marital conflicts related to personal problems of their husbands(such as extramarital affairs, gambling and alchoholism). However, they tried to overcome the structural conflicts related to authoritarian attitudes of their husbands or economic problems without any complaints. (4) Mothers have difficulty in controlling their adolescent children, due to the weakening of parental authority. Although most of the respondents perceived their employment as having negative impacts on their children, they still have high expectations toward their children. Inspite of low degree of father role expectations and facther role performance of their husbands, most of the respondents anticipated expressive roles as well as traditionally instrumental role from their husbands. Finally, these findings would help us determine family welfare policies in Korea. Improvements in paid and household labor structure of married women should be accomplished at the national level. Also, the acting programs for parent education, marital councelling services, and law enforcement for equal employment between men and women should be provided in our society.