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Perceptional Change of a New Product, DMB Phone

  • Kim, Ju-Young;Ko, Deok-Im
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.3
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    • pp.59-88
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    • 2008
  • Digital Convergence means integration between industry, technology, and contents, and in marketing, it usually comes with creation of new types of product and service under the base of digital technology as digitalization progress in electro-communication industries including telecommunication, home appliance, and computer industries. One can see digital convergence not only in instruments such as PC, AV appliances, cellular phone, but also in contents, network, service that are required in production, modification, distribution, re-production of information. Convergence in contents started around 1990. Convergence in network and service begins as broadcasting and telecommunication integrates and DMB(digital multimedia broadcasting), born in May, 2005 is the symbolic icon in this trend. There are some positive and negative expectations about DMB. The reason why two opposite expectations exist is that DMB does not come out from customer's need but from technology development. Therefore, customers might have hard time to interpret the real meaning of DMB. Time is quite critical to a high tech product, like DMB because another product with same function from different technology can replace the existing product within short period of time. If DMB does not positioning well to customer's mind quickly, another products like Wibro, IPTV, or HSPDA could replace it before it even spreads out. Therefore, positioning strategy is critical for success of DMB product. To make correct positioning strategy, one needs to understand how consumer interprets DMB and how consumer's interpretation can be changed via communication strategy. In this study, we try to investigate how consumer perceives a new product, like DMB and how AD strategy change consumer's perception. More specifically, the paper segment consumers into sub-groups based on their DMB perceptions and compare their characteristics in order to understand how they perceive DMB. And, expose them different printed ADs that have messages guiding consumer think DMB in specific ways, either cellular phone or personal TV. Research Question 1: Segment consumers according to perceptions about DMB and compare characteristics of segmentations. Research Question 2: Compare perceptions about DMB after AD that induces categorization of DMB in direction for each segment. If one understand and predict a direction in which consumer perceive a new product, firm can select target customers easily. We segment consumers according to their perception and analyze characteristics in order to find some variables that can influence perceptions, like prior experience, usage, or habit. And then, marketing people can use this variables to identify target customers and predict their perceptions. If one knows how customer's perception is changed via AD message, communication strategy could be constructed properly. Specially, information from segmented customers helps to develop efficient AD strategy for segment who has prior perception. Research framework consists of two measurements and one treatment, O1 X O2. First observation is for collecting information about consumer's perception and their characteristics. Based on first observation, the paper segment consumers into two groups, one group perceives DMB similar to Cellular phone and the other group perceives DMB similar to TV. And compare characteristics of two segments in order to find reason why they perceive DMB differently. Next, we expose two kinds of AD to subjects. One AD describes DMB as Cellular phone and the other Ad describes DMB as personal TV. When two ADs are exposed to subjects, consumers don't know their prior perception of DMB, in other words, which subject belongs 'similar-to-Cellular phone' segment or 'similar-to-TV' segment? However, we analyze the AD's effect differently for each segment. In research design, final observation is for investigating AD effect. Perception before AD is compared with perception after AD. Comparisons are made for each segment and for each AD. For the segment who perceives DMB similar to TV, AD that describes DMB as cellular phone could change the prior perception. And AD that describes DMB as personal TV, could enforce the prior perception. For data collection, subjects are selected from undergraduate students because they have basic knowledge about most digital equipments and have open attitude about a new product and media. Total number of subjects is 240. In order to measure perception about DMB, we use indirect measurement, comparison with other similar digital products. To select similar digital products, we pre-survey students and then finally select PDA, Car-TV, Cellular Phone, MP3 player, TV, and PSP. Quasi experiment is done at several classes under instructor's allowance. After brief introduction, prior knowledge, awareness, and usage about DMB as well as other digital instruments is asked and their similarities and perceived characteristics are measured. And then, two kinds of manipulated color-printed AD are distributed and similarities and perceived characteristics for DMB are re-measured. Finally purchase intension, AD attitude, manipulation check, and demographic variables are asked. Subjects are given small gift for participation. Stimuli are color-printed advertising. Their actual size is A4 and made after several pre-test from AD professionals and students. As results, consumers are segmented into two subgroups based on their perceptions of DMB. Similarity measure between DMB and cellular phone and similarity measure between DMB and TV are used to classify consumers. If subject whose first measure is less than the second measure, she is classified into segment A and segment A is characterized as they perceive DMB like TV. Otherwise, they are classified as segment B, who perceives DMB like cellular phone. Discriminant analysis on these groups with their characteristics of usage and attitude shows that Segment A knows much about DMB and uses a lot of digital instrument. Segment B, who thinks DMB as cellular phone doesn't know well about DMB and not familiar with other digital instruments. So, consumers with higher knowledge perceive DMB similar to TV because launching DMB advertising lead consumer think DMB as TV. Consumers with less interest on digital products don't know well about DMB AD and then think DMB as cellular phone. In order to investigate perceptions of DMB as well as other digital instruments, we apply Proxscal analysis, Multidimensional Scaling technique at SPSS statistical package. At first step, subjects are presented 21 pairs of 7 digital instruments and evaluate similarity judgments on 7 point scale. And for each segment, their similarity judgments are averaged and similarity matrix is made. Secondly, Proxscal analysis of segment A and B are done. At third stage, get similarity judgment between DMB and other digital instruments after AD exposure. Lastly, similarity judgments of group A-1, A-2, B-1, and B-2 are named as 'after DMB' and put them into matrix made at the first stage. Then apply Proxscal analysis on these matrixes and check the positional difference of DMB and after DMB. The results show that map of segment A, who perceives DMB similar as TV, shows that DMB position closer to TV than to Cellular phone as expected. Map of segment B, who perceive DMB similar as cellular phone shows that DMB position closer to Cellular phone than to TV as expected. Stress value and R-square is acceptable. And, change results after stimuli, manipulated Advertising show that AD makes DMB perception bent toward Cellular phone when Cellular phone-like AD is exposed, and that DMB positioning move towards Car-TV which is more personalized one when TV-like AD is exposed. It is true for both segment, A and B, consistently. Furthermore, the paper apply correspondence analysis to the same data and find almost the same results. The paper answers two main research questions. The first one is that perception about a new product is made mainly from prior experience. And the second one is that AD is effective in changing and enforcing perception. In addition to above, we extend perception change to purchase intention. Purchase intention is high when AD enforces original perception. AD that shows DMB like TV makes worst intention. This paper has limitations and issues to be pursed in near future. Methodologically, current methodology can't provide statistical test on the perceptual change, since classical MDS models, like Proxscal and correspondence analysis are not probability models. So, a new probability MDS model for testing hypothesis about configuration needs to be developed. Next, advertising message needs to be developed more rigorously from theoretical and managerial perspective. Also experimental procedure could be improved for more realistic data collection. For example, web-based experiment and real product stimuli and multimedia presentation could be employed. Or, one can display products together in simulated shop. In addition, demand and social desirability threats of internal validity could influence on the results. In order to handle the threats, results of the model-intended advertising and other "pseudo" advertising could be compared. Furthermore, one can try various level of innovativeness in order to check whether it make any different results (cf. Moon 2006). In addition, if one can create hypothetical product that is really innovative and new for research, it helps to make a vacant impression status and then to study how to form impression in more rigorous way.

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A Study of the Attitude of/and Problems Encountered by Senjor Home Economist Toward the Integration of Family Planning Education in the Korean Formal School System (가정학교육 영역에서의 인구교육문제에 관한 조사연구 -선임가정학자들을 대상으로-)

  • 김지화
    • Journal of the Korean Home Economics Association
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    • v.19 no.3
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    • pp.83-101
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    • 1981
  • Under the full consideration of the growing need and importance of population education in the field of home economics in Korea, the study was carried out to verify and assess the following facts on the current issues of population education of home economists who are presently engaging in teaching professions as the teachers of middle and high school and professors of college and universities by setting its primary objectives of the study as followings; 1) to assess the degree of general knowledge and attitudes of home economists toward population education in the field of home economics, 2) to verify the problems encountered in implementing population education by home economists in its field, 3) to find an existing status of previous trainings received and other activities of population education of home economists aimed at utilizing these findings as a part of reference materials when the population education is conducted in the field of home economics. In order to attain these objectives described above, the questionnaire was carefully designed to house a total of 40 questions with good combination of multiple-choice and the simple answer questions. The mail questionnaire survey was conducted by establishing teachers of home economics at middle/high schools and college/universities as Senior Home Economists(SHE) who are from public, private liberal arts and vocational schools. The rate of response observed during the survey was 45.6 percent and the findings of the survey research are as follows: 1) Examining the status of the respondents by residence and religion, it was found that 45 percent of middle & high school teachers ar.d 59. 1 percent of college professors are residing in Seoul city area and that the largest percent of them are christian in their religion. Analyzing respondents by their ages, 56 percent of middle/high school teachers are in their 30s, 45 percent of college professors are in their 40s, and 37 percent of college teachers are in their 30s. In addition, 13 percent of the total respondents are found to be unmarried. The study also revealed that 71 percent of the college professors finished Master Degree course and 82 percent of middle/high school teachers are graduated from college level lasting 4 years. Looking over the status cf major fields of respondents, 68.4 percent of middle/high school teachers are specialized in home economic education and the college professors, on the other hand, show relatively even prortion by specializing in the order of food & nutrition science, clothes & textile science and home managerial science. As far as the length of teaching experience is concerned, a relatively longer period of teaching experience is observed in the college professors in comparison with that of middle/high school teachers. In other words, 33.3 percent of middle/high school teachers are experienced in teaching from 6 to 10 years on average while 43.9 percent of college professors show more than 16 years of experience. 2) Examining the status of existing number of children cf the respondents, one boy and one daughter pattern is predominant, showing 28.5 percent in middle/high school teachers and 21.1 percent in college professors. As for the desired number of children of unmarried respondents, it is observed that 43.8 percent of middle/high school teachers desire to have one boy and one girl, and 31.3 percent of college professors want to have one child regardless of the sex. By assessing the degree of awareness of the population education through their students, it is observed that 53 percent of middle/high school teachers and 50 percent of college professors are aware of population education in some extent and that a majority of respondents took the positive attitudes toward an inclusion of family planning components into the formal school education. Another noteworthy to observe is that a total of 84.8 percent out of middle/high school teachers pointed that the population education currently conducted at schools as a part of home economics are less sufficient than it should be. 3) Analyzing the tendency as to whether the respondents were experienced in receiving population education during the time when they were students, 75 percent of college professors and 59 percent of middle/high school teachers responded negative answers in the survey. In the mean time, a total of 50 percent of the respondents replied that they began to acknowledge the importance of population education mainly through the participation of some sort of population-education orientend seminars, experienced by 40 percent of college professors and 80 percent of middle/high school teachers. 4) What it calls attention in this study was to find that 96.5 percent of middle/high school teachers and 72 percent of college professors conduct population education to some extent during their lecture hours and that more than 80 percent of them are never experienced in teaching population and family planning contents in their regular classes. It is, on the other hand, found that no more than once was the response of those who believe themselves that they are experienced in teaching these relevant components to their students. Analyzing the contents of the subjects being taught in the class, a large percent of them are found to be consisted of population and family planning contents. According to this study, the current population education through the formal school is quite inactive. Analyzing the facts, 44.9 percent of the college professors responded that the population and family planning components are quite apart from their specialization which eventually generates lack of interest in the field. 5) It is also noticed through the study that the degree of frequency of commenting on population and family planning contents during the classes was depending significantly on their specializations which means that the degree of frequency varies from a major to another. Those who majored in home managerial science was the first one, as compared to others who majored in different specializations. Glancing over the status of correlations between ages of the respondents and numbers of seminar paticipation, it is quite clear that the aged group participated more than the younger group did, and that the most highest number of participations made by college professors were those who are in 50s. In addition, it is also found that those who are aged 20s and 60s of the respondents were the group who comments least on the contents of population and family planning at their classes. The suggestions and recommendation made through this survey research are as follows. 1) No one denies that the rapid increase of population, as compared to the limited size of land and resources, will certainly affect adversly to an enhancement of individual life quality which will, eventually, bring forth the poverty of the nation. This is the reasson why we are insisting that the world population be controlled up to an optimum level with a matter of global concerns. It is our understading that the primary aim for reducing number of population is believed to be attained only by conducting the systematic and comprehensive population education through the formal schools. Therefore, the role of home economists in the field of population/family planning education is considered very importment due to the fact that an ultimate goal of population education is placed in elevating the quality of family life by having optimum number of children through family planning program. 2) It is quite clear that home economists as teachers of formal school in all level are invited to pay their attention on redefining the ultimate goal of education and that of population education. We also understant that the primary objective of population education is to change the norm and value of the clients by replenishing the students with pertinent knowledge and attitudes on population and its related problems through a sort of education in order to attain the ultimate goal for enhancing the quality of life. There is no exception in the theory of home economics. An altimate goal of home economics is to elevate the general quality of life through an establishment of value existed in daily life. Considering the relations between population education and home economics, it is quite indespensable to bandle population components as an integral part in the field of home economics. We believe, therefore, that the senior home economists positive participation in the effort population control is more needed than it has been. 3) It is also strongly urged that population education should be a part of instructor training course for home economics. In other words, the teacher of home economics should be well aware of population and its problems by teaching interrelationship between population education and home economics, needs, contents and methods of population education during the instructor training courese for home economics. In addition, the senior home economists should be encouraged through positive participation on the short term training by types of domestic and international seminar, workshop, etc. 4) We certainly believe that the population education can not sustain itself without any backing-up of information and findings' of various and comprehensive researches of natural and social sciences. Accordingly, every senior home economist is invited to exert their maximum effort to conduct systematic study with an aim to utilize these findings and information at best in population education in the field of home economics. Therefore, we consider that the development of training material is imminent in order to provide effective and efficient population education through the for training of home economies. It should be noted that these training materials must be carefully designed, tailored and developed to meet the different classes of trainees under the considerations as to whether it is easily adaptable and infusable into the curricula of every field of home economics, and it is acceptable in the degree of difficulty and quality in its contents. 5) It is true that there are many domestic and international research rapers, reports and findings in the field of population education and family planning. However, there is a tendency that the most of research papers are heavily relying on the authors intension and preferences in its expression and publication. Under these circumstances, it is urged that the home economists should aware of the growing need of the technical training in order to keep these available information and research findings reprocessed and redesigned to insure the practical application into the population education in the field of home economics in Korea.

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A study on the impacts of infection control education on dental hygienists' perceptions for hepatitis type B and their practices to prevent infection (감염관리교육이 서울지역 치과위생사의 B형 간염에 대한 인식 및 감염방지행위 실천에 미치는 영향에 관한 연구)

  • Kim, Bo-Young;Park, Ji-Man;Park, Eun-Jin
    • The Journal of Korean Academy of Prosthodontics
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    • v.52 no.4
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    • pp.287-297
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    • 2014
  • Purpose: The purpose of this study is to examine the impacts of infection control education on dental hygienists' perceptions for hepatitis B and their behaviors. Materials and methods: Study participants were chosen by random selection among dental hygienists working in Seoul, Korea. A total of 150 questionnaires were sent out for the survey from April 2013 to May 2013, of which 140-excluding incomplete responses-were used for the study. Chi-square tests and t-tests were used (SPSS 19.0), and post-hoc analysis was performed as well. The maximum significance level was 0.05. Results: Average 1.53 times infection control education was taken, but dental hygienists' perceptions for hepatitis B and their behaviors did not show statistical differences whether the education was done or not. Practices to prevent infection showed differences depending on categories, especially disinfection and sterilization were well performed by educated group. The most common reasons for not taking the education and noncompliance with infection prevention guidelines are lack of time and opportunity due to busy schedule. Conclusion: 1. The more highly educated, the greater number of patients per day, and the greater size of hospitals, the better infection control education was conducted. 2. Although hepatitis B is one of the most common chronic liver diseases in Korea, no significant correlation between perceptions of hepatitis B and infection control education was found. 3. Dental hygienists who received infection control education performed more efficient practices for protection against infections than those who did not.

Studies on the Correlation between Sodium Chloride Metabolism and Blood Pressure of Koreans (한국사람의 뇨중식염배설량과 혈압과의 상호관계에 관한 연구)

  • Kim, Ku-Ja
    • The Korean Journal of Physiology
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    • v.8 no.2
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    • pp.19-31
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    • 1974
  • In oder to study the correlation between daily urinary output of sodium chloride and blood pressure, twenty four hour urine samples were collected from 224 cases (70 male and 154 female) of healthy Koreans whose age varied from 18 to 70 years old. The volume and concentration of sodium, chloride and potassium and total nitrogen were measured, along with the resting blood pressure. Results obtained are summarized as follows; 1. Daily urinary output was increased as a function of age. However, daily urinary output per unit sulface area was maintained at approximately 800 to 900 $ml/m^2$ in all age groups of male and it increased as a function of age in female groups. There was no significant difference between male and female. 2. The daily urinary sodium concentration was decreased gradually acceding to age in both sexes. Daily excretion of sodium was constant regardless of age in both sexes but especially high in 25-39 year female age group, which was slightly greater in males than in females. 3. The daily urinary chloride concentration was at approximately 250 meq/L in all age groups of male and which decreased as a function of age in females. 4. Hence the daily urinary output of sodium chloride was constant in all age groups of males which increased as a function of age in female groups. However, daily excretion of sodium chloride per unit sulface area was maintained at approximately 11 $gm/m^2$ in males and which increased as a function of age in females. 5. The daily urinary excretion of potassium was constant regardless of age in both sexes. 6. Urinary K/Na ratio was maintained at approximately 0.27 in males and 0.33 in females. 7. The daily urinary output of total nitrogen amount was approximately $8{\sim}10$ gm in males and $7{\sim}9$ gm in females. However, daily urinary output of nitrogen per unit sulface area was constant regardless of age in both sexes. 8. The systolic blood pressure was increased gradually according to the age in both sexes and was higher for males than females under 40 years of age. However, there was no significant difference between both sexes in ages over 40 years. 9. Quantitative comparisons indicated that daily urinary output and sodium chloride excretion are higher while daily potassium output, nitrogen excretion and urinary K/Na ratio are significantly lower among Koreans than a among Occidentals. These findings suggest that average Koreans live on low-protein and high-salt diet throughout their livers. Statistical result obtained may he summarized as follows; 10. The relation between blood pressure and sodium concentration of urine. The correlation between systolic blood pressure and sodium concentration was negatively associated for both sexes and the correlation coefficient was significant for females $({\gamma}_1=-.19<-{\gamma}_{152},\;_{0.05}=-0.159)$ and it was not significant for males $({\gamma}_1=-.19>-{\gamma}_{68},\;_{0.05}=-0.232)$ tut may be due to the sample size for males. The correlation between diastolic blood Pressure and sodium concentration was negatively associated for both sexes and the correlation coefficient was significant for males $({\gamma}_1=-.37<-{\gamma}_{68},\;0.05=-0.232)$ and the relation was not significant for females $({\gamma}_1=-.11>-{\gamma}_{152},\;_{0.05}=-0.159)$. 11. The relation between blood pressure and daily urinary sodium chloride excretion. The association between systolic blood pressure and sodium chloride excretion was positively correlated for both sexes and the relation was significant for females $({\gamma}_1=.20>{\gamma}_{152},\;_{0.05}= 0.159)$ and it was insignificant for males $({\gamma}_1=.09<{\gamma}_{68},\;_{0.05}=0.232)$, The relation between diastolic blood pressure and sodium chloride excretion was positively associated and insignificant for both sexes males $({\gamma}_1=.17<{\gamma}_{68},\;_{0.05}=0.232)$ and females $({\gamma}_1=.09<{\gamma}_{152},\;_{0.05}=0. 159)$. 12. The relation between daily urinary nitrogen excretion and sodium chloride excretion. The association between daily nitrogen excretion and sodium chloride excretion was positively significant for both sexes, males $({\gamma}_1=.31>{\gamma}\;_{68},\;_{0.05}=0.232)$ and females $({\gamma}_1=.36>{\gamma}_{-152},\;_{0.05}=0.159)$.

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Etiological Studies on the Acute Fatal Disease of Angora Rabbits : The So-Called Rabbit Viral Sudden Death (앙고라 토끼의 급성폐사성질병(急性斃死性疾病)의 병인학적(病因學的) 연구(硏究) : 소위(所謂) 토끼의 바이러스성(性) 급사병(急死病))

  • Lee, Cha-soo;Park, Cheong-kyu
    • Korean Journal of Veterinary Research
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    • v.27 no.2
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    • pp.277-290
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    • 1987
  • This paper dealt with etiological studies on the acute fatal disease of Angora rabbits occurring as a group in Korea. The disease was confirmed as an acute infectious disease caused by virus. The results obtained were summarized as follows: The disease produced a high morbidity in the rearing Angora rabbits and a high mortality in the infected rabbits, and was acute. The infected rabbits died soon without premonitory signs after inappetence. The body temperature of the affected rabbits rose to $40^{\circ}C$ and nearly all deaths occurred within 48 hours after inoculation. In many cases a bloody foam was visible from the nostrils after death. According to the progress of the disease the nervous signs, such as ataxia, paralysis of the legs, and torticollis could be recognized in the some cases. Rabbits that had recovered from the disease were severe emaciation, and bristly and sparse hairs. In macroscopical findings, there were hemorrhage and edema of the lung, hemorrhage or hyperemia of the tracheal and broncheal mucosae, appearance of blood-tinged effusion in the respiratory tract. The principal lesions were found in the liver. Usually the lobular necrosis of the liver cells was progressed, and focal necrosis and hemorrhagic spots of various sizes were often observed in the liver. Liver was as a whole pale. In chronic cases, however, there was a slight liver cirrhosis with the atrophy of the parenchymal cells. The other lesions encountered grossly consisted of swelling and petechiae of the kidney, hyperemia and hemorrhage of the spleen, catarrh of the small intestine, and hyperemia of the brain. The urinary bladder contained a lot of turbid urine or bloody urine and urinary cast, and was distended with the urine. In microscopical findings, the most striking lesions occurred in the liver and may be classified as viral hepatitis. The hepatic lesions were initially characterized by progression from periportal to peripheral necrosis of the lobules with the infiltration of mononuclear cells. Focal necrosis of various sizes, hemorrhage and hyperemia were often observed in the hepatic lobules. In chronic cases, there were intensive infiltration of lymphocytes, proliferation of fibroblasts, appearance of plasmal cells, and atrophy of parenchymal cells in the hepatic tissue. Perivascular lymphocytic infiltration and meningitis were seen in the brain and spinal cord. In the kidney, there were acute glomerulonephritis, hemorrhage, necrosis of the uriniferous tubules, and retention of eosinophilic substance within the renal tubules. Proliferation of fibroblasts and infiltration of mono-nuclear cells were found in the interstitial stroma of the kidney in chronic case. There were also hemorrhage and edema in the lung, hyperemia and hemorrhage in the trachea and bronchus, perivascular lymphocytic infiltration and focal myocardial necrosis in the heart, hyperemia and hemorrhage in the spleen, vacuolization and desquamation of mucous epithelia in the urinary bladder, catarrhal inflammation of the small intestine, hemorrhage in the adrenal cortex and hyperemia in the other organs. In the electron microscopical findings of the hepatic tissue, crystals of viral particles appeared in the cytoplasm of the hepatocytes and the sinusoidal endothelial cells, and the viral particles, were small in size and polygonal. The authors suppose the virus may belong to picornaviridae family of RNA viruses. Also immature virus-like particles, dilated rough endoplasmic reticulum and destruction of nuclear membrane were seen in the hepatocytes. From these results, it is concluded that the sudden death is an acute viral disease characterized by hepatitis and the affected rabbits may be died of viremia.

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An evaluation of the adequacy of pont's index (Pont 지수의 임상적 적합성에 대한 평가)

  • Kim, Seong-Hun;Lee, Ki-Soo
    • The korean journal of orthodontics
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    • v.30 no.1 s.78
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    • pp.115-126
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    • 2000
  • Dental arch expansion is one of the method used to solve the dental crowding problem by non-extraction. Many formulae using tooth size have been suggested to predict ideal inter-premolar and inter-molar width. The purpose of this study was to evaluate the adequacy of some upper dental arch width prediction methods, namely Pont's method, Schmuth's method and Cha's method. The sample consisted of the casts of 119 Korean young adults who had no muscular abnormality, no skeletal discrepancy, and Angle's Class I molar relationships. Measurements were obtained directly from plaster casts; they Included mesiodistal crown diameters of the four maxillary incisors, as well as maxillary inter-first-premolar and inter-first-molar arch widths as specified by Pont. The correlation coefficients between the sum of incisors(SI) and upper dental arch width were calculated. The differences between predicted width and actual width were classified as overestimated, properestimated, and underestimated. The data obtained from each group were analyzed for statistical differences. The results were as follows : 1. Upper dental arch width indices were calculated from SI in normal occlusion (81.96 : premolar index, 62.55 : molar index). 2. Low correlations between SI and arch width were noted in normal occlusion (0.50 in the inter-premolar width, 0.39 in the inter-molar width). 3. Pont's formula and Schmuth's formula tended to overestimate the inter-premolar width. A more even distribution of estimates was noted in Cha's fomula. 4. Cases within $\pm$1 mm range of observed inter-premolar width were $45\%$ in the Cha's formula, $40\%$ in the Pont's formula, and $39\%$ in the Schmuth's formula. 5. All formulae had a tendency to underestimate the inter-molar width, but Cha's formula had better predictability than others. 6. Cases within $\pm$1 mm range of observed inter-molar width were $40\%$ in the Cha's formula, $29\%$ in the Pont's formula, and $13\%$ of Schmuth's formula. The data presented in this study does not support the clinical usefulness of ideal arch width prediction methods using the mesiodistal width of maxillary incisors.

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Distribution and Population Dynamics of Korean Endangered Species; Hipparchia autonoe (Lepidoptera: Nymphalidae) on Mt. Hallasan, Jeju Island, Korea (한국산 멸종위기종 산굴뚝나비(나비목, 네발나비과)의 분포와 개체군 동태)

  • Kim, Do-Sung;Cho, Young-Bok;Kim, Dong-Soon;Lee, Yeong-Don;Park, Seong-Joon;Ahn, Nung-Ho
    • Korean Journal of Environment and Ecology
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    • v.28 no.5
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    • pp.550-558
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    • 2014
  • This study was conducted to investigate the distribution and the population dynamics of Hipparchia autonoe by using a line transect and Mark-Release-Recapture (MRR) at the Mt. Halla in Jeju Island. The results showed that H. autonoe was found from 1,500 m above the sea level. Total 1,493 H. autonoe with 978 males and 515 females were captured and released in the MRR study site. Among them, 518 individuals including 284 males and 234 females were recaptured. The average survival time was 2.31 days with 2.14 days for males and 3.47 days for females, indicating longer survival time in case of females than males. The daily population size of males estimated in the MRR study site was maintained about 1,000 individuals in July and gradually decreased less than 200 in August. The number of females showed peak at 335 individuals on July 24, and gradually decreased less than 120 in August. Thus, female population was 1/3 of males. The average travel distance of male and female H. autonoe were $116.8{\pm}191.9m$ and $118.4{\pm}161.5m$, respectively, indicating almost same between sexes. H. autonoe in the Mt. Halla formed single population group in the wide meadow around the Baekrokdam Lake. The highest population density of H. autonoe was occurred in the restored area from damages, where host plants such as the sheep's fescue or the food plant are abundant by artificial restoration efforts.

The Influence of the Dissolved Oxygen of Bottom Water on the Temporal Variation of the Benthic Polychaetous Community Structure in Dangdong Bay (저층수 용존산소가 당동만 저서다모류군집 구조의 시간적 변동에 미친 영향)

  • Yang, Jin Kyeong;Shin, Hyun Chool
    • Ocean and Polar Research
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    • v.42 no.3
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    • pp.233-247
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    • 2020
  • This study was carried out at 5 sites 11 times over two years to identify the variation of benthic environments and benthic polychaetous community and analyze the benthic healthiness in Dangdong Bay, a small semi-enclosed inner bay of Jinhae Bay. The temperature of bottom water showed the typical temporal fluctuation of a temperate zone and was in the range of 5.94 ~ 23.94℃. The salinity did not change significantly during the study period and was in the range of 32.93 ~ 35.72 psu. The concentration of dissolved oxygen of bottom water fluctuated a great deal and was in the range of 0.31 ~ 10.20 mg/L. The lowest DO value was recorded in July 2015, as 0.31±0.04 mg/L corresponding to the hypoxic water mass. The hypoxic water mass was formed continuously at some sites also in July and August 2016. The mean grain size was in the range of 7.57 ~ 9.81Ø and the average was 8.89±0.20Ø. The surface sediments were mainly composed of fine sediment (mud) above 85%. The mean of TOC was 3.09±0.22% and LOI was 13.30±0.47%, showing very high levels in Korean coastal waters. The concentration of AVS was in the range of 0.33 ~ 1.28 mgS/g-dry. The high values of organic contents and AVS indicated that there had been the serious organic enrichment in Dangdong Bay. The number of species and the density of the benthic polychaetous community in Dangdong Bay were in the range of 2 ~ 38 species and 2 ~ 2,185 ind./㎡ during the study period. The number of species and density were highly sustained in winter and spring, and then decreased gradually with the formation of a hypoxic water mass in summer, and the lowest number of species and density were recorded in autumn. In September and November 2015, the dead zone expanded to almost the whole study area. Dominant polychaetous species were Capitella capitata, Lumbrineris longifolia, Paraprionospio patiens and Sigambra tentaculata, each known as opportunistic species and potential organic pollutant indicator species. In particular, Paraprionospio patiens showed a very high population density of 2,019 ind./㎡ in December 2016. Polychaetous communities at each sampling time were classified into 4 temporal groups according to dominant species in each period by cluster analysis and nMDS. 'Period Group AI' was formed in winter and spring of 2015, dominated by Capitella capitata, 'Period AII' in summer dominated by Lumbrineris longifolia, 'Period B' in autumn with no fauna in the dead zone, and particularly 'Period C' in winter of 2016 dominated by Paraprionospio patiens. As a result of analysis of benthic healthiness, the study area was estimated to be in a Fair~Very Poor condition by AMBI and in a Poor~Very Poor condition by BPI during the study period. Both AMBI and BPI showed that the study area was in a Very Poor condition in September and November 2015, and when the dead zone occurred. In Dongdong Bay, the fact that the formation of a hypoxic water mass occurred in summer and a dead zone in autumn were confirmed. In addition, the dominance of opportunistic and organic pollutant indicator species was also observed clearly. The benthic healthiness indexes such as AMBI and BPI showed that organic enrichment was serious in Dangdong Bay.

The Status of Endangered Plants Distributed in the Middle Eastern Area of Korea and Evaluation of the Risk Factors (우리나라 중동부지역에 분포하는 멸종위기야생식물 현황과 위험요인 평가)

  • Kim, Young-Chul;Chae, Hyun-Hee;Hong, Bo-Ram;Oh, Hyun-Kyung;Lee, Kyeong-Hwa;Lee, Kyu-Song
    • Korean Journal of Environment and Ecology
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    • v.30 no.3
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    • pp.291-307
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    • 2016
  • Evaluation of the extinction risk of endangered plants at international, national as well as at regional levels is essential to the implementation of plans for direct conservation activities. Reports indicate that 34 endangered plants are distributed in the middle eastern area of Korea. For each endangered plant, we investigated the sites, area of extents, population size, and factors that affect population extinction. We assessed risk factors based on 10 evaluation criteria including the results from the investigation and the life traits each endangered plant has. As a result of evaluating the risk factors, these 34 endangered plants are classified into 3 groups: the first category comprises 12 endangered plants that require active and urgent conservation of habitats due to multiple risk factors; the second group has 16 endangered plants that should be able to persist with the removal of a few direct risk factors; the third category has 6 endangered plants that can persist with minimal management due to comparatively large distributed area and numerous individuals. It was found that most major risk factors in the population of endangered plants are caused by disruption of habitats and population extinction due to the increase of human habitation in the concerned areas, development and illegal harvesting. Futhermore, ecological collapse from decreasing habitats and malfunctioning mechanism of extinction and regeneration due to the changes of vegetational environment can be the other causes. From the area of the present investigations, we selected 5 regions according to the number of species and the frequency of appearance and importance of conservation measures. Also, we suggested a conservation strategy according to the regional characteristics. We suggest that the method for evaluating extinction risk of endangered plants includes distributional data and life traits of species. In addition, we underscore the necessity for understanding population dynamics and ecological niche of the each target species.

The Study on the Priority of First Person Shooter game Elements using Delphi Methodology (FPS게임 구성요소의 중요도 분석방법에 관한 연구 1 -델파이기법을 이용한 독립요소의 계층설계와 검증을 중심으로-)

  • Bae, Hye-Jin;Kim, Suk-Tae
    • Archives of design research
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    • v.20 no.3 s.71
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    • pp.61-72
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    • 2007
  • Having started with "Space War", the first game produced by MIT in the 1960's, the gaming industry expanded rapidly and grew to a large size over a short period of time: the brand new games being launched on the market are found to contain many different elements making up a single content in that it is often called the 'the most comprehensive ultimate fruits' of the design technologies. This also translates into a large increase in the number of things which need to be considered in developing games, complicating the plans on the financial budget, the work force, and the time to be committed. Therefore, an approach for analyzing the elements which make up a game, computing the importance of each of them, and assessing those games to be developed in the future, is the key to a successful development of games. Many decision-making activities are often required under such a planning process. The decision-making task involves many difficulties which are outlined as follows: the multi-factor problem; the uncertainty problem impeding the elements from being "quantified" the complex multi-purpose problem for which the outcome aims confusion among decision-makers and the problem with determining the priority order of multi-stages leading to the decision-making process. In this study we plan to suggest AHP (Analytic Hierarchy Process) so that these problems can be worked out comprehensively, and logical and rational alternative plan can be proposed through the quantification of the "uncertain" data. The analysis was conducted by taking FPS (First Person Shooting) which is currently dominating the gaming industry, as subjects for this study. The most important consideration in conducting AHP analysis is to accurately group the elements of the subjects to be analyzed objectively, and arrange them hierarchically, and to analyze the importance through pair-wise comparison between the elements. The study is composed of 2 parts of analyzing these elements and computing the importance between them, and choosing an alternative plan. Among these this paper is particularly focused on the Delphi technique-based objective element analyzing and hierarchy of the FPS games.

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