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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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Development of a Stock Trading System Using M & W Wave Patterns and Genetic Algorithms (M&W 파동 패턴과 유전자 알고리즘을 이용한 주식 매매 시스템 개발)

  • Yang, Hoonseok;Kim, Sunwoong;Choi, Heung Sik
    • Journal of Intelligence and Information Systems
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    • v.25 no.1
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    • pp.63-83
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    • 2019
  • Investors prefer to look for trading points based on the graph shown in the chart rather than complex analysis, such as corporate intrinsic value analysis and technical auxiliary index analysis. However, the pattern analysis technique is difficult and computerized less than the needs of users. In recent years, there have been many cases of studying stock price patterns using various machine learning techniques including neural networks in the field of artificial intelligence(AI). In particular, the development of IT technology has made it easier to analyze a huge number of chart data to find patterns that can predict stock prices. Although short-term forecasting power of prices has increased in terms of performance so far, long-term forecasting power is limited and is used in short-term trading rather than long-term investment. Other studies have focused on mechanically and accurately identifying patterns that were not recognized by past technology, but it can be vulnerable in practical areas because it is a separate matter whether the patterns found are suitable for trading. When they find a meaningful pattern, they find a point that matches the pattern. They then measure their performance after n days, assuming that they have bought at that point in time. Since this approach is to calculate virtual revenues, there can be many disparities with reality. The existing research method tries to find a pattern with stock price prediction power, but this study proposes to define the patterns first and to trade when the pattern with high success probability appears. The M & W wave pattern published by Merrill(1980) is simple because we can distinguish it by five turning points. Despite the report that some patterns have price predictability, there were no performance reports used in the actual market. The simplicity of a pattern consisting of five turning points has the advantage of reducing the cost of increasing pattern recognition accuracy. In this study, 16 patterns of up conversion and 16 patterns of down conversion are reclassified into ten groups so that they can be easily implemented by the system. Only one pattern with high success rate per group is selected for trading. Patterns that had a high probability of success in the past are likely to succeed in the future. So we trade when such a pattern occurs. It is a real situation because it is measured assuming that both the buy and sell have been executed. We tested three ways to calculate the turning point. The first method, the minimum change rate zig-zag method, removes price movements below a certain percentage and calculates the vertex. In the second method, high-low line zig-zag, the high price that meets the n-day high price line is calculated at the peak price, and the low price that meets the n-day low price line is calculated at the valley price. In the third method, the swing wave method, the high price in the center higher than n high prices on the left and right is calculated as the peak price. If the central low price is lower than the n low price on the left and right, it is calculated as valley price. The swing wave method was superior to the other methods in the test results. It is interpreted that the transaction after checking the completion of the pattern is more effective than the transaction in the unfinished state of the pattern. Genetic algorithms(GA) were the most suitable solution, although it was virtually impossible to find patterns with high success rates because the number of cases was too large in this simulation. We also performed the simulation using the Walk-forward Analysis(WFA) method, which tests the test section and the application section separately. So we were able to respond appropriately to market changes. In this study, we optimize the stock portfolio because there is a risk of over-optimized if we implement the variable optimality for each individual stock. Therefore, we selected the number of constituent stocks as 20 to increase the effect of diversified investment while avoiding optimization. We tested the KOSPI market by dividing it into six categories. In the results, the portfolio of small cap stock was the most successful and the high vol stock portfolio was the second best. This shows that patterns need to have some price volatility in order for patterns to be shaped, but volatility is not the best.

Development of a Device for Estimating the Optimal Artificial Insemination Time of Individually Stalled Sows Using Image Processing (영상처리기법을 이용한 스톨 사육 모돈의 인공수정적기 예측 장치 개발)

  • Kim, D.J.;Yeon, S.C.;Chang, H.H.
    • Journal of Animal Science and Technology
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    • v.49 no.5
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    • pp.677-688
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    • 2007
  • 돼지를 포함한 대부분의 동물은 일정한 발정주기를 가지고 일정한 시기에 배란을 하는 자연배란동물이지만, 토끼, 고양이, 밍크 등의 암놈은 교미자극에 의해 배란이 일어나는 유기배란동물이다. 또한 1년에 한 번만 발정하는 단발정동물과 1년에 수차례 발정하는 다발정동물이 있다. 이 중에서 모돈은 1년에 수차례 발정하는 다발정 동물로서 발정기에 들면 비발정기와는 다른 행동을 나타낸다(Diehl 등, 2001). 양돈가의 수익을 최대화하기 위해서는 비생산일수를 최소로 줄여야 한다. 모돈의 비생산일수를 줄일 수 있는 한 가지 방법은 성공적으로 교배를 시키는 것이다. 이처럼 성공적으로 교배를 시키기 위해서는 수정적기를 정확히 예측해야 한다. 만약 수정적기를 정확히 판단하지 못하여 수태가 되지 않으면, 비생산일수가 늘어나 손실을 입게 된다. 따라서 수정적기를 정확히 판단하는 것은 모돈의 성공적인 인공수정에 있어서 중요한 요소이다. 수정적기는 배란이 일어나기 전 10시간에서 12시간 사이이며, 발정이 시작되는 시점을 기준으로 하였을 때 경산돈의 경우 26시간에서 34시간 사이이고 미경산돈의 경우는 18시간에서 26시간 사이이다(Evans 등, 2001). 현재 하루에 두 번 모돈의 발정을 확인하는 것이 일반화되어 있으며, 이 때 웅돈을 접촉시키거나 육안관찰을 통하여 발정 유무를 판단한다. 이러한 방법에는 숙련된 기술과 풍부한 경험이 요구될 뿐만 아니라 총 소요노동력의 30% 정도가 요구된다(Perez 등, 1986). 하루에 두 번밖에 발정을 감지하지 않기 때문에 발정이 언제 시작되었는지를 정확히 알 수 없으며, 또한 발정의 대부분이 새벽에 시작되므로 수정적기를 정확히 판단하기란 매우 어렵다. 만약 발정을 감지했더라도 적기에 인공수정을 하지 못한다면, 수태율이 낮아지므로 경제적 손실이 초래된다. 현재 이러한 문제점 때문에 2회에서 3회에 걸쳐 인공수정을 하고 있으나 이에 따른 소요비용과 소요노동력 등은 양돈가의 부담을 가중시키는 요인이 되고 있다. 돼지는 발정기가 되면 비발정기에 나타내지 않던 외음부의 냄새를 맡는 행동, 귀를 세우는 행동 및 승가허용 행동 등을 나타낸다(Diehl 등, 2001). 또한 돼지는 비발정기에 비하여 발정기에 더 많은 활동량을 나타낸다(Altman, 1941; Erez and Hartsock, 1990). Freson 등(1998)은 스톨에서 개별적으로 사육되고 있는 모돈의 활동량을 적외선센서를 이용하여 측정함으로써 발정을 86%까지 감지하였다고 보고하였다. 그러나 이 연구는 단지 모돈의 발정을 감지하였을 뿐 번식관리에 있어서 가장 중요한 수정적기의 판단 기준을 제시하지 못하였다. 따라서, 본 연구는 스톨에서 사육되는 모돈의 활동량을 측정함으로써 발정시작시각을 감지하고 이를 기준으로 인공수정적기를 예측할 수 있는 인공수정적기 예측 장치를 개발한 후 이의 성능을 농장실증실험을 통하여 시험하고자 수행되었다.

Home Economics Teachers' Perception of Cultural Diversity Education (문화다양성 교육에 대한 가정과교사의 인식)

  • Si, Se-In;Lee, Eun-Hee
    • Journal of Korean Home Economics Education Association
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    • v.26 no.4
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    • pp.115-128
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    • 2014
  • The purpose of this study was to investigate home economics teachers' perception of cultural diversity education, to provide an efficient educational material for the multicultural education in teacher education and teacher retraining. 160 Home economics teachers answered the survey questionnaires. To analyze the data, SPSS 19.0 for Windows was used to conduct frequency analysis, factorial analysis, credibility analysis, t-test, one-way ANOVA, and Duncan's multiple comparison. The results of this study were as follows. Four dimensions of cultural diversity education were derived by factor analysis: cultural equality, diversity implementation, diversity value, comfort with diversity. As for their awareness about cultural diversity education, it was in the order of cultural equality, followed by diversity implementation, diversity value, and comfort with diversity. The groups were significantly different according to demographic variables. As for the whole awareness about cultural diversity education and the diversity implementation, group of age 40 teachers recognized more highly than other groups. Furthermore, teachers outside Jeonbuk area recognized more highly the cultural equality, diversity implementation, diversity value than those in Jeonbuk, which is the 3rd high area in the nation of multicultural family proportion. As for cultural equality and diversity implementation, teachers over 15 years of experience, recognized more highly than other groups. Those with the teacher certification in the college of education, recognized more highly the cultural equality, diversity value, comfort with diversity than teachers from the other colleges. Teachers who need multicultural education, recognized more highly cultural equality, diversity implementation, awareness of diversity than those who don't. These results imply that in home economics education, there must be more systematic studies on school field education and related educational programs in order to revitalize multicultural education. And for teachers with highly recognizing cultural diversity to conduct a systematic multicultural education more efficiently, there should be both systematic pre-service education programs at college level and in-service education programs for the teachers in terms of cultural diversity education.

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A Study and Survey on Clinical Nurses concerning the General Items, the Motives of Determining their Profession, the Attitudes toward their Profession and the Desire and Expectation to their Profession and Society (임상간호원에 대한 연구조사)

  • 이귀향;우옥자;서문자
    • Journal of Korean Academy of Nursing
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    • v.3 no.3
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    • pp.78-96
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    • 1973
  • This study of 855 clinical nurses was conducted using a questionnaire that include tour different scales; the motives of determining their profession, the attitudes toward their profession, the general items, and desire and expectation to their profession and society. The data were analyzed by Chi-Square Test and Percentage. The results of this study included Hypothesis are as follows; The respondents were 855 (78.6%) among 1088 clinical nurses who were employed by General of Educational hospitals through the city of Seoul, Pusan, Taegu, Daejun, Kwangju, and Wonju. 1) a. In the Age Distribution, the majority of respondents were under the age of 30yrs(88.2%) and the minority were above 31yrs(11.2%), and the preponderance of the majority to minority(9:1) was noted. In compared with area, a group above 31yrs old in Seoul (6.9%) was lower than other area (16.3%). b. The types of Educational background were 16.3% in Voc.Tr. School, 66.5% in Diploma and 17.1% in Degree.146 clinical nurses were from the Degree course, and 142 (97.3%) CN among those of them were occupied around Seoul and 4(2.7%) around other area. c. In the Marital Status,71,5% were the unmarried and 28.5% were the married. And compared with the area was 20.4% in Seoul and 41.4% in other area. d. Most common Length of Clinical Experience after graduation was under tile 2yrs (55.4%), 3yrs(14.2%, and 4yrs (6.2%). In compared with area, Seoul (15.3%) was lower than other area (38.1%) above 5yrs of clinical experience, and the preponderance of tile other area to Seoul as 2.5: I was noted. 2) a. Hypothesis 1 was significant relation between the types of Educational Background of the CN and their motives for selection of Nursing, P-value was below 0.01. b. There was a significance on hypothesis 2 (P<0.01): that was relation between their motives for selection of clinical nursing field after their graduation and the area which they were employed. c. Hypothesis 4 was accepted as significant relation between the level of satisfaction of their clinical experience after their graduation and the types of educational back ground, P-value was below 0.01. d. There was a significance on hypothesis 5(P<0.01) that was relation between the CN's response about the orientation program and the area which they were employed. e. Hypothesis 6 was retained as significant relation between the area and inservice educational programme of their employed hospital was practising or not. P-value was 0.01. f. Hypothesis 7 was retained as significant relation between the area and the CN's response about the inservice educational programme of their employed. P-value was below 0.01. g. There was a significance on hypothesis 8 (P<0.0l) that was relation between the CN's experience on attending the professional meeting and the area. h. Hypothesis 10 was accepted as significant relation between the response about the present licence system and their educational background. p-value was below 0.01. i. There was a significance on hypothesis 11 (P fO.01) that was relation between the carrying out the regular and delivery vacation and the area. J. Hypothesis 12 was accepted as significant relation between the CN's consideration of the lack of leisure and their marital status. p-value was below 0.01' k. There was a significance on hypothesis 13 (P <0.01) that was relation between the CN's response about their salary and their marital status. l. Hypothesis 14 was significant relation between the most difficulties of CN during their working and the hospital which they were employed. p-value was below 0.01.

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The Satisfaction of Inpatient Families and Bereaved Families in the Hospice Service (호스피스 병동에 입원한 환자 가족과 사별 가족의 만족도)

  • Park, Theresia;Ra, Jeong-Ran;Seo, In-Ok;Cho, Young-Yee;Choi, Suk-Kyung;Park, Myung-Hee;Heo, Jeong-Hee;Kim, Eun-Kyung
    • Journal of Hospice and Palliative Care
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    • v.2 no.2
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    • pp.91-100
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    • 1999
  • Purpose : This study was performed to investigate the satisfaction in the hospice services provided for inpatient families and bereaved families whose members had been admitted to the hospice unit at Kangnam St. Mary's Hospital to improve the quality of care for the terminally ill patients and their families. Methods : This sample consisted of 33 families of hospice patients during the period of April to lune, 1998 and 30 bereaved families whose patients had died from March, 1993 to March, 1998. The data were collected through a self-report questionnaire and analyzed using t-test and ANOVA. Results : 1) The satisfaction level of inpatient families and bereaved families showed the mean value of 3.5 where the highest value is 5.0. 2) According to age, the level of satisfaction of inpatient families had significant differences in the fields of hospice philosophy, support for the family, medical management and nursing management(P=0.0001). The level of satisfaction of bereaved families showed significant differences in the field of support for the family, medical management, nursing management, and facilities of the hospice unit(P=0.0001). 3) By family relationship, the level of satisfaction of inpatient families had significant differences in the fields of hospice philosophy, support for the family, medical management and nursing management (P=0.0001). 4) According to religion, the level of satisfaction of inpatient families had significant differences in the fields of hospice philosophy, support for the family and nursing management (P=0.0001), but there was no significant difference for the bereaved families. Conclusions : The findings of this study showed that hospice services had positive influence on families with terminal disease such as cancer. To improve the level of satisfaction in the hospice services for families with hospice patients, we need to provide care by an interdisciplinary hospice team approach, and to assess needs of the families according to their socio-psychological characteristics. Further studies need to be conducted with large samples.

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Factors Affecting Participation Intention of the 4th Industrial Technology Education: Applying MGB Model (4차 산업혁명 기술교육의 참여의도에 영향을 미치는 요인 연구: 목표지향행동모델(MGB)을 중심으로)

  • Lee, Jihyun;Dong, Haklim
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.4
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    • pp.231-244
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    • 2020
  • With the rapid progress of the 4th industrial revolution, technical human capitals are considered to be the core competing factors of the enterprise. Technical manpower training of the 4th industrial revolution through technical education has become an essential task of venture start-ups. The opening of technical training courses and the education support system of companies are increasing, but the shortage of technical manpower is getting worse. This study was conducted to analyze the factors affecting participation intention of the 4th industrial revolution technology education. The research model was established based on the model of goal-directed behavior. For the analysis, 250 valid questionnaire data were used to test with a structural equation model. The results of the study are as follows. First, attitude had a positive effect on the intention to participate in education. Second, subjective norms had a positive effect on the intention to participate in education. Third, the perceived behavioral control has not been tested for a significant influence on educational participation intention. Fourth, positive and negative anticipated emotions had a significant effect on educational intention. The impact of significant variables were found in the order of positive anticipated emotions, attitudes, negative anticipated emotions, subjective norms. On the other hand, as a result of testing the mediating effect of desires, it was found that desires plays a mediating role between attitude, subjective norm, perceived behavioral control, positive anticipated emotions, negative anticipated emotions, and participation intention. In particular, the causal relationship between perceived behavioral control and intention to participate in education was not significant, but perceived behavioral control had a significant effect(full mediation) on participation intention through desires. Based on the results of this study, the following implication were suggested. First, the model of goal-directed behavior(MGB) was applied to the technical education field. Second, the direct relationship between antecedent variables and behavioral intentions was simultaneously tested. Third, unlike the existing education-related research, the factors affecting participation in education were analyzed. Fourth, the importance of desires for education were suggested.

The Design of Mobile Medical Image Communication System based on CDMA 1X-EVDO for Emergency Care (CDMA2000 1X-EVDO망을 이용한 이동형 응급 의료영상 전송시스템의 설계)

  • Kang, Won-Suk;Yong, Kun-Ho;Jang, Bong-Mun;Namkoong, Wook;Jung, Hai-Jo;Yoo, Sun-Kook;Kim, Hee-Joung
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2004.11a
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    • pp.53-55
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    • 2004
  • In emergency cases, such as the severe trauma involving the fracture of skull, spine, or cervical bone, from auto accident or a fall, and/or pneumothorax which can not be diagnosed exactly by the eye examination, it is necessary the radiological examination during transferring to the hospital for emergency care. The aim of this study was to design and evaluate the prototype of mobile medical image communication system based on CDMA 1X EVDO. The system consists of a laptop computer used as a transmit DICOM client, linked with cellular phone which support to the CDMA 1X EVDO communication service, and a receiving DICOM server installed in the hospital. The DR images were stored with DICOM format in the storage of transmit client. Those images were compressed into JPEG2000 format and transmitted from transmit client to the receiving server. All of those images were progressively transmitted to the receiving server and displayed on the server monitor. To evaluate the image quality, PSNR of compressed image was measured. Also, several field tests had been performed using commercial CDMA2000 1X-EVDO reverse link with the TCP/IP data segments. The test had been taken under several velocity of vehicle in seoul areas.

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Soil Testing for Potassium in Upland Soils -Review on the Methodologies- (밭토양(土壤)에 대(對)한 가리(加里) 검정(檢定))

  • Hong, Chong Woon
    • Korean Journal of Soil Science and Fertilizer
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    • v.10 no.3
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    • pp.153-170
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    • 1977
  • Considering the ways for the possible improvement of soil test for upland crops, various methods for the evaluation of K supplying power and testing of available soil K were reviewed in terms of theoretical principles and practical usefulness of the each method. The review was also made on the characteristics of upland crops in K requirement and on the chemical properties of major korean upland and lowland rice soils in terms of K availability. Following is the few remarks drawn from the review. 1. Quite large number of methods have been known for the evaluation of K supplying power and testing for available soil K. In nature, they can be divided into two categories; capacity-based methods and intensity-based methcds. The capacity-based methods usually measure the exchangeable and some portion of nonexchangeable K, while the intensity-based methods suggest to consider the ractivity ratios of major cations in soil solution and the energy requirement for the replacement of exchangeable soil K into soil solution. 2. As methodology for extraction of interested part of soil K, chemical extraction, electrodialysis and ion exchange methods have been known. Among these, chemical extract ion is favorable because of its simplicity. However, recently suggested Electro-Ultra-Filtration method seems to merit further study for wider use for not only K but also other nutrient availability of soils. 3. The intensity-based methods, although they are more theoretical, because of their complexity, in methods may not be adapted for practical soil tests. 4. The exchangeable K which is rather simple to measure and which well reflects the status of K reserve as nonexchangeable and is immediate pool of water soluble K may be good, if not best, criterion of soil K availability to plant in common soil testing. 5. Because there are evidences that the abundance of available K alone may not be good inclication for availability of K to plant, it is recommendable to interprete the exchangeable K data as percent saturation of exchangeable K to total C. E. C. of soil for the recommend ation of K fertilizer based on soil tests. 6. Some pot and field trial results showed the trends that percent potassium saturation to total C. E. C. better serve as the parameter for K fertilizer recommendation.

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Acute toxicity of some pesticides on five Korean native Cladocerans (한국산 물벼룩에 대한 수종 농약의 급성독성)

  • Kim, Byung-Seok;Park, Yoen-Ki;Park, Kyung-Hun;Jeong, Mi-Hye;You, Are-Sun;Yang, Yu-Jung;Shin, Jin-Sup;Kim, Jin-Hwa;Yoon, Seong-Myeong;Ahn, Young-Joon
    • The Korean Journal of Pesticide Science
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    • v.11 no.4
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    • pp.261-267
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    • 2007
  • The acute toxicity of several pesticides on 4 Korean water flea was investigated to develop a new standard species used for ecological risk assessment of pesticide. Four Korean freshwater cladocerans, Daphnia obtusa, Daphnia sp., Moina macrocopa and Simocepholus vetulus were exposed to five different pesticides during 48 hours to compare their sensitivity with a standard test species, Daphnia magna, endorsed formally by the major international organizations. The synthetic pyrethroid, fenpropathrin was the most toxic pesticide to cladocerans. Diazinon, carbofuran, iprodione and myclobutanil were in the order of their toxicity to cladocerans tested. There was no consistent difference in sensitivity to five pesticides for four Korean cladocerans tested. In conclusion, the ecological risk assessment using single species toxicity referred to base set data should not be enough to protect to every species in the field environment.