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The Research on Online Game Hedonic Experience - Focusing on Moderate Effect of Perceived Complexity - (온라인 게임에서의 쾌락적 경험에 관한 연구 - 지각된 복잡성의 조절효과를 중심으로 -)

  • Lee, Jong-Ho;Jung, Yun-Hee
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.2
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    • pp.147-187
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    • 2008
  • Online game researchers focus on the flow and factors influencing flow. Flow is conceptualized as an optimal experience state and useful explaining game experience in online. Many game studies focused on the customer loyalty and flow in playing online game, In showing specific game experience, however, it doesn't examine multidimensional experience process. Flow is not construct which show absorbing process, but construct which show absorbing result. Hence, Flow is not adequate to examine multidimensional experience of games. Online game is included in hedonic consumption. Hedonic consumption is a relatively new field of study in consumer research and it explores the consumption experience as a experiential view(Hirschman and Holbrook 1982). Hedonic consumption explores the consumption experience not as an information processing event but from a phenomenological of experiential view, which is a primarily subjective state. It includes various playful leisure activities, sensory pleasures, daydreams, esthetic enjoyment, and emotional responses. In online game experience, therefore, it is right to access through a experiential view of hedonic consumption. The objective of this paper was to make up for lacks in our understanding of online game experience by developing a framework for better insight into the hedonic experience of online game. We developed this framework by integrating and extending existing research in marketing, online game and hedonic responses. We then discussed several expectations for this framework. We concluded by discussing the results of this study, providing general recommendation and directions for future research. In hedonic response research, Lacher's research(1994)and Jongho lee and Yunhee Jung' research (2005;2006) has served as a fundamental starting point of our research. A common element in this extended research is the repeated identification of the four hedonic responses: sensory response, imaginal response, emotional response, analytic response. The validity of these four constructs finds in research of music(Lacher 1994) and movie(Jongho lee and Yunhee Jung' research 2005;2006). But, previous research on hedonic response didn't show that constructs of hedonic response have cause-effect relation. Also, although hedonic response enable to different by stimulus properties. effects of stimulus properties is not showed. To fill this gap, while largely based on Lacher(1994)' research and Jongho Lee and Yunhee Jung(2005, 2006)' research, we made several important adaptation with the primary goal of bringing the model into online game and compensating lacks of previous research. We maintained the same construct proposed by Lacher et al.(1994), with four constructs of hedonic response:sensory response, imaginal response, emotional response, analytical response. In this study, the sensory response is typified by some physical movement(Yingling 1962), the imaginal response is typified by images, memories, or situations that game evokes(Myers 1914), and the emotional response represents the feelings one experiences when playing game, such as pleasure, arousal, dominance, finally, the analytical response is that game player engaged in cognition seeking while playing game(Myers 1912). However, this paper has several important differences. We attempted to suggest multi-dimensional experience process in online game and cause-effect relation among hedonic responses. Also, We investigated moderate effects of perceived complexity. Previous studies about hedonic responses didn't show influences of stimulus properties. According to Berlyne's theory(1960, 1974) of aesthetic response, perceived complexity is a important construct because it effects pleasure. Pleasure in response to an object will increase with increased complexity, to an optimal level. After that, with increased complexity, pleasure begins with a linearly increasing line for complexity. Therefore, We expected this perceived complexity will influence hedonic response in game experience. We discussed the rationale for these suggested changes, the assumptions of the resulting framework, and developed some expectations based on its application in Online game context. In the first stage of methodology, questions were developed to measure the constructs. We constructed a survey measuring our theoretical constructs based on a combination of sources, including Yingling(1962), Hargreaves(1962), Lacher (1994), Jongho Lee and Yunhee Jung(2005, 2006), Mehrabian and Russell(1974), Pucely et al(1987). Based on comments received in the pretest, we made several revisions to arrive at our final survey. We investigated the proposed framework through a convenience sample, where participation in a self-report survey was solicited from various respondents having different knowledges. All respondents participated to different degrees, in these habitually practiced activities and received no compensation for their participation. Questionnaires were distributed to graduates and we used 381 completed questionnaires to analysis. The sample consisted of more men(n=225) than women(n=156). In measure, the study used multi-item scales based previous study. We analyze the data using structural equation modeling(LISREL-VIII; Joreskog and Sorbom 1993). First, we used the entire sample(n=381) to refine the measures and test their convergent and discriminant validity. The evidence from both the factor analysis and the analysis of reliability provides support that the scales exhibit internal consistency and construct validity. Second, we test the hypothesized structural model. And, we divided the sample into two different complexity group and analyze the hypothesized structural model of each group. The analysis suggest that hedonic response plays different roles from hypothesized in our study. The results indicate that hedonic response-sensory response, imaginal response, emotional response, analytical response- are related positively to respondents' level of game satisfaction. And game satisfaction is related to higher levels of game loyalty. Additionally, we found that perceived complexity is important to online game experience. Our results suggest that importance of each hedonic response different by perceived game complexity. Understanding the role of perceived complexity in hedonic response enables to have a better understanding of underlying mechanisms at game experience. If game has high complexity, analytical response become important response. So game producers or marketers have to consider more cognitive stimulus. Controversy, if game has low complexity, sensorial response respectively become important. Finally, we discussed several limitations of our study and suggested directions for future research. we concluded with a discussion of managerial implications. Our study provides managers with a basis for game strategies.

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Purchasing Status and Supplier Performance Evaluation of School Foodservice in Chanwon, Korea (창원시 학교급식 식재료 구매 실태 및 공급업체 수행도 평가)

  • Jung, Hoi-Jung;Kim, Hyun-Ah
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.6
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    • pp.861-869
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    • 2012
  • This study was conducted to investigate the purchasing status and to compare supplier performance evaluations between competitive bidding and negotiated contracts in school foodservice in Changwon, Korea. A total of 190 questionnaires were distributed and 167 (return rate 87.9%) were collected from June 29 to September 28, 2010, and then a total of 151 (analysis rate 79.5%) were used for the final analysis. First, 91.4% of food product purchases for school meals were contracted through competitive bidding, especially limited competitive bidding. It mainly consisted of agricultural products, processed food, and eco-friendly agricultural products (fruit). Second, 78.8% of schools purchased food products by negotiated contracts, while single negotiation accounted for 59.7%. Food products by negotiated contract consisted of meat, kimchi, and fish. Third, the purchase status of competitive bidding and negotiated contracts showed a significant difference in agricultural products (p<0.001), fish (p<0.001), meats (p<0.001), poultry (p<0.001), antibiotic-free poultry (p<0.001), eco-friendly grain (p<0.001), eco-friendly agricultural products (fruit) (p<0.001), eco-friendly processed food (p<0.001), processed products (p<0.001), milk (p<0.001) and general grain (p<0.001) except for kimchi. Fourth, comparative analysis of supplier performance evaluation (on a 5-point Likert scale) of school foodservice showed that price of product of competitive bidding (3.73) was significantly higher than that of negotiated contract (2.95) (p<0.001), and the overall performance level of the negotiated contract (3.85) was significantly higher than that of competitive bidding (3.61) (p<0.01). The supplier performance evaluation levels of product packaging (p<0.01), product quality at the time of delivery (p<0.001), hygiene of products (p<0.001), consistency to specification (p<0.001), swiftness of return and exchange (p<0.001), emergency delivery (p<0.001), service of delivery staff (p<0.05), and handling of complaints (p<0.001) of negotiated contracts were significantly higher than those of competitive bidding of school foodservice. In conclusion, school foodservice selected food suppliers both by adopting competitive bidding and negotiated contracts. And there was a significant difference of school foodservice supplier performance between competitive bidding and negotiated contracts in Changwon, Korea.

Satisfaction and Preference of School Milk Program of Elementary School in Ulsan (울산시 초등학교 우유급식 만족도 및 기호도 분석)

  • Kim, Kyung-A;Kim, Hyun-Ah
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.3
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    • pp.408-417
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    • 2012
  • This study examined the satisfaction of a school milk program as well as the preference of school milk and flavored milk. The subjects of this study were $4^{th}$ , $5^{th}$ and $6^{th}$ grade students in 4 different elementary schools, who were attending the school milk program in Ulsan. The survey was conducted from April 10, 2009 to April 30, 2009. Of the 403 questionnaires distributed, 347 responded and analyzed (usage rate: 86%). The results were as follows. Of the 347 respondents, 53.9% were boys and 46.1% were girls. 34%, 31.1% and 34.9% of the students were $4^{th}$, $5^{th}$ and $6^{th}$ graders, respectively. Second, 80.1% of the students reported 'have milk everyday', and 89.9% of the students reported 'have milk as it is'. Third, the overall satisfaction with the school milk program was 3.32 based on a 5-point likert scale, the 'guidance of nutrition teachers and class teacher' was 3.21 and 'taste of school milk' was 3.37. There were significant positive correlations between the school milk satisfaction variables and overall satisfaction (p<0.01). Fourth, the preference for school milk was 3.33. The preference for flavored-milk were 3.63 (coffee milk), 4.44 (chocolate milk), 4.16 (strawberry milk), 4.26 (banana milk) and 3.53 (black bean milk). Fifth, to improve the school milk program, 85.9% of students wanted a provision for flavored milk. In conclusion, schools need to find a way to increase the satisfaction of the school milk program and the preference of school milk to increase the milk intake of students. Nutrition education for students and parents should be conducted systematically and choices for various kinds of milk and milk products should be given to the students.

Studies on the Physiological Chemistry of Seed Development in Ginseng Seed (인삼식물의 종자발육 과정에 있어서의 생리화학적 연구)

  • Hee-Chun Yang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.17
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    • pp.115-133
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    • 1974
  • This study was done on the metabolism of chemical components during the seed development of ginseng. The changes of the chemical components were inspected in the following periods: from the early stage of flower organ formation to flowering time, from the early stage of fruiting to maturity, during the moisture stratification before sowing. From flower bud forming stage to meiosis stage, the changes in the fresh weight, dry weight, contents of carbohydrates, and contents of nitrogen compounds were slight while the content of TCA soluble phosphorus and especially the content of organic phosphorus increased markedly. From meiosis stage to microspore stage the fresh and dry weights increase greatly. Also, the total nitrogen content increases in this period. Insolub]e nitrogen was 62-70% of the total nitrogen content; the increase of insoluble nitrogen seems to have resulted form the synthesis of protein. The content of soluble sugar (reducing and non-reducing sugar) increases greatly but there was no observable increase in starch content. In this same period, TCA soluble phosphorus reached the maximum level of 85.4% of the total phosphorus. TCA insoluble phosphorus remained at the minimum content level of 14.6%. After the pollen maturation stage and during the flowering period the dry weight increased markedly and insolub]e nitrogen also increased to the level of 67% of the total nitrogen content. Also in this stage, the organic phosphorus content decreased and was found in lesser amounts than inorganic phosphorus. A rapid increase in the starch content was also observed at this stage. In the first three weeks after fruiting the ginseng fruit grows rapidly. Ninety percent of the fresh weight of ripened ginseng seed is obtained in this period. Also, total nitrogen content increased by seven times. As the fruits ripened, insoluble nitrogen increased from 65% of the total nitrogen to 80% while soluble nitrogen decreased from 35% to 20%. By the beginning of the red-ripening period, the total phosphoric acid content increased by eight times and was at its peak. In this same period, TCA soluble phosphorus was 90% of total phosphorus content and organic phosphorus had increased by 29 times. Lipid-phosphorus, nucleic acid-phosphorus and protein-phosphorus also increased during this stage. The rate of increase in carbohydrates was similar to the rate of increase in fresh weight and it was observed at its highest point three weeks after fruiting. Soluble sugar content was also highest at this time; it begins to decrease after the first three weeks. At the red-ripening stage, soluble sugar content increased again slightly, but never reached its previous level. The level of crude starch increased gradually reaching its height, 2.36% of total dry weight, a week before red-ripening, but compared with the content level of other soluble sugars crude starch content was always low. When the seeds ripened completely, more than 80% of the soluble sugar was non-reducing sugar, indicating that sucrose is the main reserve material of carbohydrates in ginseng seeds. Since endosperm of the ripened ginseng seeds contain more than 60% lipids, lipids can be said to be the most abundant reserve material in ginseng seeds; they are more abundant than carbohydrates, protein, or any other component. During the moisture stratification, ginseng seeds absorb quantities of water. Lipids, protein and starch stored in the seeds become soluble by hydrolysis and the contents of sugar, inorganic phosphorus, phospho-lipid, nucleic acid-phosphorus, protein phosphorus, and soluble nitrogen increase. By sowing time, the middle of November, embryo of the seeds grows to 4.2-4.7mm and the water content of the seeds amounts to 50-60% of the total seed weight. Also, by this time, much budding material has been accumulated. On the other hand, dry stored ginseng seeds undergo some changes. The water content of the seeds decreases to 5% and there is an observable change in the carbohydraes but the content of lipid and nitrogen compounds did not change as much as carbohydrates.

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Biomass and distribution of Antarctic Krill, Euphausia superba, in the Northern part of the South Shetland Islands, Antarctic Ocean (남극 남쉐틀란드 군도 북부 해역의 크릴 분포 및 자원량)

  • KANG Donhyug;HWANG Doojin;KIM Suam
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.6
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    • pp.737-747
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    • 1999
  • To estimate biomass and distribution of the Antarctic krill (Euphausia superba), hydroacoustic survey was conducted on board of R/V Yuzhmorgeologiya, which was chartered by Korea Antarctic Research Program (KARP) group from 18 to 21 December 1998, in the northern part of the South Shetland Islands, Antarctic Ocean, The scientific echo sounder (towing body type) used was EK- 500 (SIMRAD, Norway) with echo integrator (BI-500) at 38 kHz frequency and recorded mean backscattering cross-section coefficient (SA) per 1 $mile^2$ of sea surface. Also, Bongo net sampling was carried out to determine the size of krill and CTD (Conductivity, Temperature and Depth) casting to understand physical structure. Water column was divided into 5 layers (22$\~$65 m, 65$\~$115 m, l15$\~$65 m, 165$\~$215 m and 215$\~$315 m) to know vertical distribution of krill biomass. The standard length of krill collected was between 30 mm and 51 mm, and adult krill had single mode (41 mm). Maximum horizontal length of krill patch was about 35 nautical mile and vertical thickness was about 275 m. High density of krill was appeared in frontal area between Circumpolar Deep Water (>$1^{\circ}C$) and very low temperature water mass (< $-0.5^{\circ}C$) that originate from Weddell Sea. According to the results calculated using target strength equation, krill density was totally higher in continental slope and open water areas than in coastal area. In the study area, krill seems to distribute in depth; density was low at first layer ($\={\rho}=17.0\;g/m^2$) and higher at fourth layer ($\={\rho}=40.19\;g/m^2$). The estimated krill biomass at total survey area and water column was about 2.77 million metric ion ($\={\rho}=151.0\;g/m^2$) and coefficient of valiance ( CV, $\%$) was 19.92. The proportions and biomass of krill biomass at each layer were as follows; layer 1 ($11.3\%$, 0.31 million metric ton, CV=16.24), layer 2 ($13.3\%$, 0.37 million metric ton, CV=34.91), layer 3 ($23.7\%$, 0.66 million metric ton, CV=41.5), layer 4 ($26.6\%$, 0.74 million metric ton, CV=27.84) and layer 5 ($25\%$, 0.69 million metric ton, CV= 26.83).

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Late Rectal Complication in Patients treated with High Dose Rate Brachytherapy for Stage IIB Carcinoma of the Cervix (FIGO병기 IIB 자궁경부암에서 고선량 강내 방사선치료후의 후기 직장 합병증)

  • Chung, Eun-Ji;Kim, Gwi-Eon;Suh, Chang-Ok;Keum, Ki-Chang;Kim, Woo-Cheol
    • Radiation Oncology Journal
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    • v.14 no.1
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    • pp.41-52
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    • 1996
  • Purpose : This paper reports a dosimetric study of 88 patients treated with a combination of external radiotherapy and high dose rate ICR for FIGO stage IIB carcinoma of the cervix. The purpose is to investigate the correlation between the radiation doses to the rectum, external radiation dose to the whole pelvis, ICR reference volume, TDF BED and the incidence of late rectal complications, retrospectively. Materials and Methods : From November 1989 through December 1992, 88 patients with stage IIB cervical carcinoma received radical radiotherapy at Department of Radiation Oncology in Yonsei University Hospital. Radiotherapy consisted of 44-54 Gy(median 49 Gy) external beam irradiation plus high dose rate intracavitary brachytherapy with 5 Gy per fraction twice a week to a total dose of 30 Gy on point A. The maximum dose to the rectum by contrast(r, R) and reference rectal dose by ICRU 38(dr, DR) were calculated. The ICR reference volume was calculated by Gamma Dot 3.11 HDR planning system, retrospectively The time-dose factor(TDF) and the biologically effective dose (BED) were calculated. Results : Twenty seven($30.7\%$) of the 88 patients developed late rectal complications:12 patients($13.6\%$) for grade 1, 12 patients($13.6\%$) for grade 2 and 3 patients($3.4\%$) for grade 3. We found a significant correlation between the external whole pelvis irradiation dose and grade 2, 3 rectal complication. The mean dose to the whole pelvis for the group of patients with grade 2, 3 complication was Higher, $4093.3\pm453.1$ cGy, than that for the patients without complication, $3873.8\pm415.6$ (0.05$7163.0\pm838.5$ cGy, than that for the Patients without rectal complication, $0772.7\pm884.0$ (p<0.05). There was no correlation of the rate of grade 2, 3 rectal complication with the iCR rectal doses(r, dr), ICR reference volume, TDF and BED. Conclusion : This investigation has revealed a significant correlation between the dose calculated at the rectal dose by ICRU 38(DR) or the most anterior rectal dose by contrast(R) dose to the whole pelvis and the incidence of grade 2, 3 late rectal complications in patients with stage IIB cervical cancer undergoing external beam radiotherapy and HOR ICR. Thus these rectal reference points doses and whole pelvis dose appear to be useful Prognostic indicators of late rectal complication in high dose rate ICR treatment in cervical carcinoma.

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Biodistribution of 3-[$^{131}I$]iodo-O-methyl-L-${\alpha}$-methyltyrosine in Tumor Bearing Rats: A Comparison Study with L-3-[$^{131}I$]iodo-${\alpha}$-methyltyrosine (종양 이식 백서에서 3-[$^{131}I$iodo-O-methyl-L-${\alpha}$-methyltyrosine의 체내 동태 연구: L-3-[$^{131}I$iodo-${\alpha}$-methyltyrosine와 비교)

  • Choi, Chang-Woon;Yang, Seung-Dae;Woo, Kwang-Sun;Chung, Wee-Sup;Lim, Soo-Jung;Suh, Yong-Sup;Chun, Kwon-Soo;Ahn, Soon-Hyuk;Lee, Jong-Doo;Hong, Sung-Woon;Lim, Sang-Moo
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.3
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    • pp.290-297
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    • 1998
  • Purpose : The aim of this study was to evaluate the feasibility of 3-[$^{131}I$]iodo-O-methyl-L-${\alpha}$-methyltyrosine ([$^{131}I$]OMIMT) as an agent for tumor image. Materials and Methods : After synthesis of 4-O-methyl-L-${\alpha}$-methyltyrosine (OMAMT), OMAMT was labeled with [$^{131}I$] using Iodogen method. In vitro cellular uptake study was performed using 9 L gliosarcoma cells at various time points upto 4 hr. The biodistribution (five rats implanted with the 9 L gliosar-coma cells per group) was evaluated at 30 min, 2 hr, 24 hr after iv injection of 3.7 MBq [$^{131}I$]OMIMT or L-3-[$^{131}I$]iodo-${\alpha}$-methyltyrosine [$^{131}I$]IMT). Gamma camera images were obtained at 30 min, 2 hr and 24 hr. Results: [$^{131}I$]OMIMT uptake was 3.3 times and 2.5 times higher than [$^{131}I$]IMT uptake at 30 min and 60 min, respectively and same after 2 hr in in vitro study using 9L gliosarcoma cells. Maximum accumulation in tumor occurred at 30 min for both [$^{131}I$]OMIMT and [$^{131}I$]IMT in tumor bearing rats. The tumor uptake of [$^{131}I$]OMIMT was significantly higher than that of [$^{131}I$]IMT at early time point studied ($3.74{\pm}0.48$ vs $0.38{\pm}0.17%$ ID/g at 30 min and $2.40{\pm}0.17$ vs $0.24{\pm}0.03%$ ID/g at 2 hr, respectively, p<0.01). However, the tumor uptake of both radiolabels were not significantly different at 24 hr ($0.04{\pm}0.01$ vs $0.05{\pm}0.01%$ ID/g). Tumor was visualized as early as at 30 min in gamma camera images. Conclusion: These data suggested that [$^{131}I$]OMIMT might be a useful tumor imaging agent and has more advantage for the tumor imaging compared to [$^{131}I$]IMT

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A Comparison of Body Image and Dietary Behavior in Middle and High School girls in Gyeongbuk Area (경북 일부지역 여자 중·고등학생의 체형인식도 및 식생활 행동 비교)

  • Kim, Hye-Jin;Lee, Kyung-A
    • Korean journal of food and cookery science
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    • v.31 no.4
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    • pp.497-504
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    • 2015
  • The purpose of this study was to compare body image and dietary behavior in middle and high school girls in the Gyeongbuk area in September, 2014. Data were collected from a total of 194 middle school and 170 high school girls through a self-reported questionnaire. A total of 364 completed questionnaires were collected and used for the final analysis. The mean body mass index (BMI) of respondents was normal at 21.29. Generally, high school girls had greater height, weight and BMI than middle school girls. Height (p<0.001) and weight (p<0.001) were significantly different, while BMI was not. The ratio of students who perceived their body size as 'Fat' was significantly (p<0.05) higher in high school (43.9%) than in middle school (31.6%). The ratio of dissatisfaction with their current body image was significantly (p<0.001) higher in high school girls (64.1%) than in middle school girls (44.0%). Among respondents who perceived their body size as 'Fat', many high school girls actually (53.3%) had normal or low body weight and this was significantly (p<0.001) higher than in middle school girls (39.3%). Experience with weight control was higher in high school girls (67.3%) than in middle school girls (60.6%), but there was no significant difference. Regarding the weight control methods, respondents selected 'combination diet and exercise' (22.2%), 'diet control' (20.9%), 'exercise' (18.7%), and 'reduce snacks and midnight snack' (17.4%). 15 items under obesity-related dietary behavior were measured with 5-point scales and lower scores indicated obesity diet behavior. The mean score for all respondents was 3.19/5.00, and high school girls (3.06) scored significantly (p<0.001) higher than middle school girls (3.33). Our study suggests that the development of effective nutrition and health education for diet control is crucial for adolescent girls. This study will enable educators to plan more effective strategies to improve the dietary knowledge of adolescent girls.

Derivation of the Synthetic Unit Hydrograph Based on the Watershed Characteristics (유역특성에 의한 합성단위도의 유도에 관한 연구)

  • 서승덕
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.17 no.1
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    • pp.3642-3654
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    • 1975
  • The purpose of this thesis is to derive a unit hydrograph which may be applied to the ungaged watershed area from the relations between directly measurable unitgraph properties such as peak discharge(qp), time to peak discharge (Tp), and lag time (Lg) and watershed characteristics such as river length(L) from the given station to the upstream limits of the watershed area in km, river length from station to centroid of gravity of the watershed area in km (Lca), and main stream slope in meter per km (S). Other procedure based on routing a time-area diagram through catchment storage named Instantaneous Unit Hydrograph(IUH). Dimensionless unitgraph also analysed in brief. The basic data (1969 to 1973) used in these studies are 9 recording level gages and rating curves, 41 rain gages and pluviographs, and 40 observed unitgraphs through the 9 sub watersheds in Nak Oong River basin. The results summarized in these studies are as follows; 1. Time in hour from start of rise to peak rate (Tp) generally occured at the position of 0.3Tb (time base of hydrograph) with some indication of higher values for larger watershed. The base flow is comparelatively higher than the other small watershed area. 2. Te losses from rainfall were divided into initial loss and continuing loss. Initial loss may be defined as that portion of storm rainfall which is intercepted by vegetation, held in deppression storage or infiltrated at a high rate early in the storm and continuing loss is defined as the loss which continues at a constant rate throughout the duration of the storm after the initial loss has been satisfied. Tis continuing loss approximates the nearly constant rate of infiltration (${\Phi}$-index method). The loss rate from this analysis was estimated 50 Per cent to the rainfall excess approximately during the surface runoff occured. 3. Stream slope seems approximate, as is usual, to consider the mainstreamonly, not giving any specific consideration to tributary. It is desirable to develop a single measure of slope that is representative of the who1e stream. The mean slope of channel increment in 1 meter per 200 meters and 1 meter per 1400 meters were defined at Gazang and Jindong respectively. It is considered that the slopes are low slightly in the light of other river studies. Flood concentration rate might slightly be low in the Nak Dong river basin. 4. It found that the watershed lag (Lg, hrs) could be expressed by Lg=0.253 (L.Lca)0.4171 The product L.Lca is a measure of the size and shape of the watershed. For the logarithms, the correlation coefficient for Lg was 0.97 which defined that Lg is closely related with the watershed characteristics, L and Lca. 5. Expression for basin might be expected to take form containing theslope as {{{{ { L}_{g }=0.545 {( { L. { L}_{ca } } over { SQRT {s} } ) }^{0.346 } }}}} For the logarithms, the correlation coefficient for Lg was 0.97 which defined that Lg is closely related with the basin characteristics too. It should be needed to take care of analysis which relating to the mean slopes 6. Peak discharge per unit area of unitgraph for standard duration tr, ㎥/sec/$\textrm{km}^2$, was given by qp=10-0.52-0.0184Lg with a indication of lower values for watershed contrary to the higher lag time. For the logarithms, the correlation coefficient qp was 0.998 which defined high sign ificance. The peak discharge of the unitgraph for an area could therefore be expected to take the from Qp=qp. A(㎥/sec). 7. Using the unitgraph parameter Lg, the base length of the unitgraph, in days, was adopted as {{{{ {T}_{b } =0.73+2.073( { { L}_{g } } over {24 } )}}}} with high significant correlation coefficient, 0.92. The constant of the above equation are fixed by the procedure used to separate base flow from direct runoff. 8. The width W75 of the unitgraph at discharge equal to 75 per cent of the peak discharge, in hours and the width W50 at discharge equal to 50 Per cent of the peak discharge in hours, can be estimated from {{{{ { W}_{75 }= { 1.61} over { { q}_{b } ^{1.05 } } }}}} and {{{{ { W}_{50 }= { 2.5} over { { q}_{b } ^{1.05 } } }}}} respectively. This provides supplementary guide for sketching the unitgraph. 9. Above equations define the three factors necessary to construct the unitgraph for duration tr. For the duration tR, the lag is LgR=Lg+0.2(tR-tr) and this modified lag, LgRis used in qp and Tb It the tr happens to be equal to or close to tR, further assume qpR=qp. 10. Triangular hydrograph is a dimensionless unitgraph prepared from the 40 unitgraphs. The equation is shown as {{{{ { q}_{p } = { K.A.Q} over { { T}_{p } } }}}} or {{{{ { q}_{p } = { 0.21A.Q} over { { T}_{p } } }}}} The constant 0.21 is defined to Nak Dong River basin. 11. The base length of the time-area diagram for the IUH routing is {{{{C=0.9 {( { L. { L}_{ca } } over { SQRT { s} } ) }^{1/3 } }}}}. Correlation coefficient for C was 0.983 which defined a high significance. The base length of the T-AD was set to equal the time from the midpoint of rain fall excess to the point of contraflexure. The constant K, derived in this studies is K=8.32+0.0213 {{{{ { L} over { SQRT { s} } }}}} with correlation coefficient, 0.964. 12. In the light of the results analysed in these studies, average errors in the peak discharge of the Synthetic unitgraph, Triangular unitgraph, and IUH were estimated as 2.2, 7.7 and 6.4 per cent respectively to the peak of observed average unitgraph. Each ordinate of the Synthetic unitgraph was approached closely to the observed one.

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Analysis and Improvement Strategies for Korea's Cyber Security Systems Regulations and Policies

  • Park, Dong-Kyun;Cho, Sung-Je;Soung, Jea-Hyen
    • Korean Security Journal
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    • no.18
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    • pp.169-190
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    • 2009
  • Today, the rapid advance of scientific technologies has brought about fundamental changes to the types and levels of terrorism while the war against the world more than one thousand small and big terrorists and crime organizations has already begun. A method highly likely to be employed by terrorist groups that are using 21st Century state of the art technology is cyber terrorism. In many instances, things that you could only imagine in reality could be made possible in the cyber space. An easy example would be to randomly alter a letter in the blood type of a terrorism subject in the health care data system, which could inflict harm to subjects and impact the overturning of the opponent's system or regime. The CIH Virus Crisis which occurred on April 26, 1999 had significant implications in various aspects. A virus program made of just a few lines by Taiwanese college students without any specific objective ended up spreading widely throughout the Internet, causing damage to 30,000 PCs in Korea and over 2 billion won in monetary damages in repairs and data recovery. Despite of such risks of cyber terrorism, a great number of Korean sites are employing loose security measures. In fact, there are many cases where a company with millions of subscribers has very slackened security systems. A nationwide preparation for cyber terrorism is called for. In this context, this research will analyze the current status of Korea's cyber security systems and its laws from a policy perspective, and move on to propose improvement strategies. This research suggests the following solutions. First, the National Cyber Security Management Act should be passed to have its effectiveness as the national cyber security management regulation. With the Act's establishment, a more efficient and proactive response to cyber security management will be made possible within a nationwide cyber security framework, and define its relationship with other related laws. The newly passed National Cyber Security Management Act will eliminate inefficiencies that are caused by functional redundancies dispersed across individual sectors in current legislation. Second, to ensure efficient nationwide cyber security management, national cyber security standards and models should be proposed; while at the same time a national cyber security management organizational structure should be established to implement national cyber security policies at each government-agencies and social-components. The National Cyber Security Center must serve as the comprehensive collection, analysis and processing point for national cyber crisis related information, oversee each government agency, and build collaborative relations with the private sector. Also, national and comprehensive response system in which both the private and public sectors participate should be set up, for advance detection and prevention of cyber crisis risks and for a consolidated and timely response using national resources in times of crisis.

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