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Hepatitis B Virus Infection Rate of Medical School Students in Taegu (대구시내(大邱市內) 의과대학생(醫科大學生)들의 B형(型)바이러스성(性) 간염감염율(肝炎感染率))

  • Park, Jung-Han;Youn, Tae-Hyun;Chun, Byung-Yeol;Song, Jung-Hup
    • Journal of Preventive Medicine and Public Health
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    • v.20 no.1 s.21
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    • pp.129-136
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    • 1987
  • To determine the hepatitis 8 virus infection rate of the medical school students and appropriate time for immunization with hepatitis B vaccine,355 students in the 1st, 2nd and 3rd grades of Medical School of Kyungpook National University who had not been vaccinated and volunteered to participate in this study were tested for HBsAg, anti-HBs and anti-HBc with radioimmunoassay method (Abbott Lab. kit). A questionnaire was administered to ask the history of transfusion, acupuncture and surgery. HBsAg positive students were retested 16 months after the initial test. Overall HBsAg positive rate was 6.8% and the age adjusted rate for male (7.2%) was higher than that for female (4.9%). Anti-HBs positive rate was 35.3% (36.1% for male, 37.9% for female) and anti-HBc positive rate was 45.5% (46.5% for male,44.7% for female). Overall hepatitis B virus (HBV) infection rate was 49.1% and the infection rate for male (50.3%) was slightly higher than that for female (46.5%). HBsAg positive rate and infection rate were increased as the grade increased but it was attributed to the age distribution of the students. HBaAg positive rate for 20 years old students was 1.7%; 21 years, 6.6%; 22 years, 6.1%; 23 years, 12.2%; and 24 years and older, 6.4%. HBV infection rate showed an increasing trend as age increased; 45.8% for 20 years,41.5% for 21 years, 49.5% for 22 years, 55.5% for 23 years and 59.6% for 24 years and older. The age differences in HBsAg positive rates and HBV infection rates did not reach the statistical significance level of 0.05. However, these findings and similar age differences in HBsAg positive rates and HBV infection rates observed in other study suggest that there is a significant age differences. Study of the same age group in other schools and different social classes is warranted to confirm the age difference. Clarification of the reason for such differences would provide a clue to identify the major route of HBV transmission in this age group. Among 26 HBsAg positive students in the initial test, only one student was active hepatitis patient. Out of 24 students who had follow-up test after 16 months 22 students were positive for HBaAg and two students became HBsAg negative and anti-HBs positive. It is obvious that nearly one-half of the medical school students were infected with HBV before 20 years of age and the HBV infection occurs in medical school. Thus, it is recommended to test all the students for HBV infection soon after the admission to the medical school and immunize all the susceptible students with hepatitis B vaccine and give booster as they start to practice at a hospital.

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Preliminary Results of 3-Dimensional Conformal Radiotherapy for Primary Unresectable Hepatocellular Carcinoma (절제 불가능한 원발성 간암의 입체조형 방사선치료의 초기 임상 결과)

  • Keum Ki Chang;Park Hee Chul;Seong Jinsil;Chang Sei Kyoung;Han Kwang Hyub;Chon Chae Yoon;Moon Young Myoung;Kim Gwi Eon;Suh Chang Ok
    • Radiation Oncology Journal
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    • v.20 no.2
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    • pp.123-129
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    • 2002
  • Purpose : The purpose of this study 띤as to determine the potential role of three-dimensional conformal radiotherapy (3D-CRT) in the treatment of primary unresectable hepatocellular carcinoma. The preliminary results on the efficacy and the toxicity of 3D-CRT are reported. Materials and Methods : Seventeen patients were enrolled in this study, which was conducted prospectively from January 1995 to June 1997. The exclusion criteria included the presence of extrahepatic metastasis, liver cirrhosis of Child-Pugh classification C, tumors occupying more than two thirds of the entire liver, and a performance status of more than 3 on the ECOG scale. Two patients were treated with radiotherapy only while the remaining 15 were treated with combined transcatheter arterial chemoembolization. Radiotherapy was given to the field including the tumor plus a 1.5 cm margin using a 3D-CRT technique. The radiation dose ranged from $36\~60\;Gy$ (median; 59.4 Gy). Tumor response was based on a radiological examination such as the CT scan, MR imaging, and hepatic artery angiography at $4\~8$ weeks following the completion of treatment. The acute and subacute toxicities were monitored. Results : An objective response was observed in 11 out of 17 patients, giving a response rate of $64.7\%$. The actuarial survival rate at 2 years was $21.2\%$ from the start of radiotherapy (median survival; 19 months). Six patients developed a distant metastasis consisting of a lung metastasis in 5 patients and bone metastasis in one. The complications related to 30-CRT were gastro-duodenitis $(\geq\;grade\;2)$ in 2 patients. There were no treatment related deaths and radiation induced hepatitis. Conclusion : The preliminary results show that 3D-CRT is a reliable and effective treatment modality for primary unresectable hepatocellular carcinoma compared to other conventional modalities. Further studies to evaluate the definitive role of the 3D-CRT technique in the treatment of primary unresectable hepatocellular carcinoma are needed.

Examination of the Current Situations of Security Dogs and it's Development Plans (경호탐지견의 운용실태 및 발전방안)

  • Park, Hyung-Kyu;Kim, Doo-Hyun
    • Korean Security Journal
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    • no.14
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    • pp.215-234
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    • 2007
  • Our country security industry 1960's service expense of the beginning U.S. army unit it accomplishes the growth which is quick with start, currently about 2,500 triumph the security enterprises which it goes over are being active. But the majority in these enterprise about lower cotton can a forever characteristic with pressure and the manpower civil official ability insufficient back of faithlessness management and capital power. To sleep with afterwords it presents the security dogs deployment plan for an efficient security together from the research which it sees hereupon and it does. First, it cultivates the domestic mountain progress dog which is a breed which is suitable with the security dogs and the shovel flesh dog back with the security dogs. Specially the Jindo of the breed which is excellent training which is suitable in task of the security dogs it leads and if it uses appropriately, it industrializes our specific the Jindo and protection there is a possibility of getting the effect which falls to also the gist which it rears rightly. It cultivate the second, security dogs and it magnifies training. The security dogs consequently is it will be able to accomplish the task above 2 branches to training method. Namely, after finishing obedience training, it is to be in security activity it will execute guard or detection back special training which is suitable in task and it will be able to commit. Third, it uses the security dogs which is trained rightly in task. The security dogs the adult escorts, facility expense, the explosive and narcotic drug detection, it will be able to use with the other blind man guidance dogs back. The narcotic drug detection dogs which currently is used specially technique intelligence anger, when considering the tendency of the narcotic drug smuggling offense field which becomes diversification that the role very it is important is a possibility of saying at day. It cultivate a fourth, escort relation specialty manpower and it improves the breed of the security dogs. The hazard which cultivate the security dogs use necessary personnel the breed of security dogs, the security dogs training center it opens the security crane relation subject of the college which stands and (university) it improves it establishes and training which is suitable in task it is to do to execute letting in the training map company. Specially, the hazard which improves the breed of security dogs in the progress mind quality which stands against the portion where the breed improvement is demanded as the portion where the internal organs research and investment are necessary sees. The security dogs compares in labor cost and the expense holds few, if it uses the our specific domestic dogs it will be able to use efficiently in the task which is various it solves the multi branch plans for wisly with the security dogs industrial development security of course contemporary history sliced raw fish sees demands compared to being immediacy and the life which is happy business the place where it does it sees it will be able to contribute a lot as.

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The Effect of Low-Intensity Pulsed Ultrasound on Fracture Healing in the Rabbit Model (토끼모델에서 저강도 맥동초음파가 골절치유에 미치는 영향)

  • Kim, Jong-Man;Yi, Chung-Hwi;Cho, Sang-Hyun;Park, Jung-Mi;Kwon, Hyuk-Cheol;Hwang, Tae-Sun
    • Physical Therapy Korea
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    • v.9 no.1
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    • pp.81-96
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    • 2002
  • The purpose of this research was to determine the effects on the healing of fibular fractures in rabbits of low-intensity pulsed ultrasound (50 $mW/cm^2$ and 500 $mW/cm^2$) applied for periods of 4, 14 and 24 days following fibular osteotomy. Thirty-six male Japanese white rabbits were randomly divided into three groups of twelve for three treatment protocols: (1) ultrasound treatment at intensities of 50 $mW/cm^2$ and 500 $mW/cm^2$ until the 4th day following fibular osteotomy, (2) ultrasound treatment at intensities of 50 $mW/cm^2$ and 500 $mW/cm^2$ until the 14th day following fibular osteotomy, and (3) ultrasound treatment at intensities of 50 $mW/cm^2$ and 500 $mW/cm^2$ until the 24th day following fibular osteotomy. The low-intensity pulsed ultrasound was applied to only one fibula of each rabbit (these served as the experimental group). The other fibula of each rabbit served as the control group. The selection of which fibula was to be treated was made randomly. The animals were sacrificed on the 4th, 14th and 24th day after the start of ultrasound treatments. Percent of trabecular bone area and fibular radiography were carried out to compare the degree of fibular bone healing. A microscope was also used to determine any histologic changes. For statistical differences in radiological changes due to length of treatment period (4, 14 and 24 days respectively), the Wilcoxon signed-ranks test was used to compare the experimental and control groups. For statistical differences in fracture healing due to differences in ultrasound intensity, radiological studies were compared using the Mann-Whitney Test. And, to compute percentage differences in areas of trabecular bone, Two-way analysis of variance (ultrasound intensity x each group) was used. Experiment results were as follows: 1. In animals sacrificed on the 4th day, no difference was found in the radiological studies of the fibulae in the experimental and control groups (p>.05). However, experimental groups showed more rapid bone repair than control group. 2. Both radiographic and percent of trabecular bone area studies showed significant differences in rabbits sacrificed after 14 days. Fracture healing was significantly increased in the experimental group (p<.05) 3. In the animals sacrificed on the 24th day, histologic study showed rapid bone repair but fibular radiologic studies did not show statistical differences between the two groups (p>.05). 4. On the 14th day, bone union on radiograph was significantly more rapid in the treatment group with pulsed ultrasound of 50 $mW/cm^2$ than the group with 500 $mW/cm^2$ (p<.05). Histologic studies showed that both the 14 and 24 days groups had more rapid bone repair in animals treated with 50 $mW/cm^2$ ultrasound intensity than those treated with 500 $mW/cm^2$ intensity. In conclusion, it has been shown that the low-intensity pulsed ultrasound has a positive effect on bone fracture healing in the early stage and the range of pulse ultrasound from 50 $mW/cm^2$ to 500 $mW/cm^2$ is effective for fracture healing. Further study is needed to investigate the influence of pulsed ultrasound on delayed union and non-union in bone fractures and also for the clinical use of low-intensity pulsed ultrasound for bone healing in humans.

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The Effect of Rapidly Rotating Shift work on the Fatigue Level, Urinary 17-KS, $Na^+$ and $Cl^-$ Excretion (빠른 교대근무가 피로도, 요중 17-KS, $Na^+,\;Cl^-$ 배설에 미치는 영향)

  • Jung, Young-Ju
    • Journal of Korean Biological Nursing Science
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    • v.1 no.1
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    • pp.100-114
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    • 1999
  • This study was done to investigate the effects of rapidly-rotating shift work of two-day interval on fatigue level and the concentration of urinary 17-KS, $Na^+,\;Cl^-$. The subjects were 20 nursing college students(control group) and 15 nurses in a university hospital and the study was done from Apr. 21 to May 4th, 1999. In the test group, each 5 nurses were allocated to day shift(8 AM-4 PM), evening shift(4 PM-12 MN) and night shift(12 MN-8 AM) respectively. The fatigue level were measured 30 minutes after work start on the 2nd day of work shift. Urine specimens were collected at 8 AM, 4 PM and 12 MN on the 2nd day of work shift in the control group and 30 minutes before and after work on the 2nd day of work shift in the test group. The data were analyzed with SPSS(for Window, ver 7.5). Statistical analysis was performed by using t-test, paired t-test and ANOVA. The results were as follows. 1. The perceived fatigue level in shift work 1) The physical and mental fatigue level were significantly higher in night shift than that in day or evening shift(p<0.05). In the neuro-sensory fatigue level, night shift showed higher tendency than that in day or evening shift, but there were no significant differences between each shifts. 2) Comparison between the control group and the test group: Physical fatigue level was significantly higher in night shift than that in day or evening shift of the control group(P<.001). Mental fatigue level was significantly higher in day or night shift than that in evening shift of the control group(P<.05). In the neuro-sensory fatigue level, test group showed higher tendency than that in the control group, but there were no significant differences between two groups. 3) The total fatigue level was higher in night shift than that in day shift or evening shift(P<.05). In comparing with the control group, night shift and day shift showed higher total fatigue level than that in the control group(p<0.05). 2. The concentration of urinary 17-KS, $Na^+$ and $Cl^-$ In the control group, urinary 17-KS, $Na^+$ and $Cl^-$ showed higher level in afternoon that in morning and night. In the test group, cr in day and evening shift and $Na^+$ in evening shift showed higher level at the end of work. The 17-KS concentration at the begining and the end of work in three shift groups were lower than those in control group(p<0.05), however, $Cl^-$ concentration at the begining of work in day shift, and the end of work in day and evening shift were higher than those in control group(p<0.05). $Cl^-$ concentration at the begining and end of work in night shift were considerably higher than those in control group repectively(p<0.1, p<001). $Na^+$ concentration showed a higher tendency in three shift groups except at the begining of work in night shift, but there were no statistical difference. In comparing concentration of the 17-KS, $Na^+$ and $Cl^-$ among the shift groups, 17-KS concentration showed a lower tendency and $Na^+,\;Cl^-$ showed a higher tendency in night shift: The result of this study showes that biorhythm of shift work nurse was irregular. Fatigue level as the subjective index for evaluating the health problem concerning shift work was higher in night shift and proved to be in accordance with the concentration of urinary 17-KS, $Na^+$ and $Cl^-$ used as objective indices. Disturbation of biorhythm and work stress due to night shift seems to cause the health problem of nurses and decrease of work efficiency. It is considered that work regualtion is necessary for the rational management of the nursing administration.

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The Problem of Space Debris and the Environmental Protection in Outer Space Law (우주폐기물과 지구 및 우주환경의 보호)

  • Lee, Young Jin
    • The Korean Journal of Air & Space Law and Policy
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    • v.29 no.2
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    • pp.205-237
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    • 2014
  • Last 50 years there were a lot of space subjects launched by space activities of many states and these activities also had created tremendous, significant space debris contaminating the environment of outer space. The large number of space debris which are surrounding the earth have the serious possibilities of destroying a satellite or causing huge threat to the space vehicles. For example, Chinese anti-satellite missile test was conducted by China on January 11, 2007. As a consequence a Chinese weather satellite was destroyed by a kinetic kill vehicle traveling with a speed of 8 km/s in the opposite direction. Anti-satellite missile tests like this,contribute to the formation of enormous orbital space debris which can remain in orbit for many years and could interfere with future space activity (Kessler Syndrome). The test is the largest recorded creation of space debris in history with at least 2,317 pieces of trackable size (golf ball size and larger) and an estimated 150,000 debris particles and more. Several nations responded negatively to the test and highlighted the serious consequences of engaging in the militarization of space. The timing and occasion aroused the suspicion of its demonstration of anti-satellite (ASAT) capabilities following the Chinese test of an ASAT system in 2007 destroying a satellite but creating significant space debris. Therefore this breakup seemed to serve as a momentum of the UN Space Debris Mitigation Guidelines and the background of the EU initiatives for the International Code of Conduct for Outer Space Activities. The UN Space Debris Mitigation Guidelines thus adopted contain many technical elements that all the States involved in the outer space activities are expected to observe to produce least space debris from the moment of design of their launchers and satellites until the end of satellite life. Although the norms are on the voluntary basis which is normal in the current international space law environment where any attempt to formulate binding international rules has to face opposition and sometimes unnecessary screening from many corners of numerous countries. Nevertheless, because of common concerns of space-faring countries, the Guidelines could be adopted smoothly and are believed faithfully followed by most countries. It is a rare success story of international cooperation in the area of outer space. The EU has proposed an International Code of Conduct for Outer Space Activities as a transparency and confidence-building measure. It is designed to enhance the safety, security and sustainability of activities in outer space. The purpose of the Code to reduce the space debris, to allow exchange of the information on the space activities, and to protect the space objects through safety and security. Of the space issues, the space debris reduction and the space traffic management require some urgent attention. But the current legal instruments of the outer space do not have any binding rules to be applied thereto despite the incresing activities on the outer space. We need to start somewhere sometime soon before it's too late with the chaotic situation. In this article, with a view point of this problem, focused on the the Chinese test of an ASAT system in 2007 destroying a satellite but creating significant space debris and tried to analyse the issues of space debris reduction.

한국농촌의 식품금기에 관한 연구

  • 모수미
    • Journal of the Korean Home Economics Association
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    • v.5 no.1
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    • pp.733-739
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    • 1966
  • A 371 agricultural households from 26 different communities in South Korea was subjected on a study of food taboos in January of 1966. To the pregnant women, those to whom a high protein diet is particurally important, as many as 14 different kinds of foods, mostly portein rich foods, were avoided to eat. It is believed that if duck is eaten while pregnant her baby may walk like a duck in later life. Some mother have a strong aversion to the rabbit meat that her unborn baby must be a harelip. It is feared to eat chicken, shark or carp by the pregnant mother for her baby may get a gooseflesh appearance, or fish scale-like skin in later life. It is thought that if mother eats soup made of meat borns, especially chicken bones, a disfigured baby may be born. Some area informed that if mother eats crab meat her future baby will always bubble. To the child-bearing mothers 13 different kinds of foods were avoided to eat. Some believe that if raddish kimchi, soybean curd, squash are eaten while dilivery that mother may get dental decay or to lose all her teeth. Other think that highly spiced raddish kimchi cause delivery difficult. To the lactating mothers 7 different items of foods were not recommended to eat. It is a common belief that eating green vegetables, especially fresh lettuce, are restricted that her baby may stool greenish. It is said that eating ginsen-chicken soup, or ginsen tea during lactating reduces breast milk secretion. To the weaning babies 7 different kinds of foods were prohibited to fee. Eggs are not eaten because mothers think her babies will start to talk very late. Eight different items of foods in cases of gastro-intestinal diseases, 5 items for liver disease, 7 items for high blood pressure as well as for paralysis were respectively restricted. It is said that meats including pork, beef, and chicken are neither desirable for the patients of high blood pressure nor those of paralysis. To the measles children 10 varieties of foods were restricted. Especially soybean products and meats were not encouraged to use for avoiding asecond attack of measles. For the common cold 8 different kinds of foods were aversed and men think that eating of soup of undria delays a recovery. For the tuberculosis 4 kinds of foods were prohibited to eat. It is said that wine, red pepper and ginsen will stimulate lung bleeding. Many mothers had a strong aversion to fermented shrimp and fish in case of style. and 5 different items of foods were restricted. In case of menstration not so many foods were restricted as other cases, but meat soup is not eaten in this condition in some areas. Majority of food taboos in Korean villages are neither based on tribal nor religious factors. But no one knows how, since what ages, from where, these food taboos have been transmitted and spread over the country. This survey found a great variety of food taboos, aversions, traditional beliefs and prohibitions latent unknown reseasons, or non-scientific conceptions, or completely different ideas from the modern medical aspect, or somewhat fallacious and superstitious beliefs. For the vascular disease contrasting approach were found between modern the oritical therapy and popular remedy among the rural populations who largely depend on the eastern medication. Further scientific study on either side should be done to lead the patient proper way. Many restricted foods such as rabbit, duck, chicken and fish are best resources of protein rich foods which are available in the village. Emphasis should be laid upon breaking down fallacious and supersititious food taboos through the extended nutrition education activities in order to improve food habit and good eating pattern for healthier and stronger generations of Korea.

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The Case Study of the Entrepreneurship Intensive Programs and the Successful Diffusing Strategies of the Entrepreneurship Education. (벤처창업전문과정(EIP) 사업추진 성공사례와 확산전략)

  • Ha, Kyu-Soo;Rhee, Taik-Ho;Lee, Seung-Weon;Kim, Ki-Hak
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.1 no.1
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    • pp.127-156
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    • 2006
  • This paper introduced successful case studies of the EIP (Entrepreneurship Intensive Programs) programs that are planed by 5MBA (Small and Medium Business Administration) and executed by Hoseo University and Jinju National University in 2004. Therefore, the illustrations and examples used in this paper are based on the EIP programs of those schools. Currently there are five graduate schools for Entrepreneurship educations that are originated from the EIP program models and those graduateschools are actively and successfully working. The purpose of this paper is to find out the diffusing strategies of the Entrepreneurship spirits and Entrepreneurship Education programs after careful analysis and review of the EIP programs. The main factors of the Success of the EIP are as follows. First, there were excellent modules of the education process. Second, there were firm and clear goals of the education. Three, there were differentiated contents of the entrepreneurship education programs. Four. each and every education performance was monitored. Five, during the programs, real start-up cases were actually handled and students had many opportunities to present their cases. However, there were some shortcomings to improve and change of the entrepreneurship education. First of all, it was very difficult to make proper education formation that is fit in the purpose of the program. Second, motivating students to find out their own business opportunities so as to turn them into real business was not satisfactory or easy. Third, there were some limitations in distributing and executing the EIP budgets. Therefore, to improve the efficiency of the Entrepreneurship education, following expanding strategies should be complemented. First, continuous redesigning of the entrepreneurship education programs is very important. Second, the specialization of the contents of the entrepreneurship education programs is essential. Third, there should be some discretionary room for the management of the entrepreneurship programs. Fourth, it is also important activating the entrepreneurship networks among schools of the entrepreneurship education. Finally, it is necessary to give some incentives and motivations based on the proper performance evaluation system.

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An Empirical Study on Influence of Venture Preparation on Business Performance of Initial Venture Foundation: Focused on The Effect of Controlling The Period of Venture Preparation (창업준비성이 창업초기기업 경영성과에 미치는 영향에 관한 실증연구: 창업준비기간의 조절효과 중심)

  • Oh, jaiwoo;Lee, Donghyung;Kang, Jinkyu
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.10 no.4
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    • pp.67-80
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    • 2015
  • Although recent policies and regulations in Korea strongly advocate and encourage cultivation of venture foundations, studies on venture foundation and success are very limited and often primarily focus on entrepreneurship or individual quality as a venture founder in addition to such studies' validity in question. Therefore, this study primarily focuses on venture preparation process which is subject to venture founder's effort to verify the policy effectiveness in the relationship between venture preparation and business performance. Major goal of this study is to reduce social cost of venture failure by suggesting systematic policy support for venture foundations and analyzing the relationship between following variables: first, venture preparation and financial performance, second, venture preparation and non-financial performance, and third, venture preparation and business performance. 400 initial venture foundations less than 5 years are selected from KISED(Korea Institute Startup & Entrepreneurship Development) trend analysis to carry out statistical analysis using SPSS 18.0. To organize the data features, frequency analysis as well as descriptive statistics are performed to verify the hypothesis. As a result, sub-factors in measurement of venture preparation which are venture education period, venture benefit, and experience of incubating organization are selected as independent variables. Likewise, sub-factors in measurement of business performance which are financial performance and non-financial performance are used as dependent variables. To validate interactive effect, venture preparation period is selected as control variable to perform hierarchical regression analysis. The analysis result verifies that venture benefit has positive influence on financial and non-financial performance while venture education period has positive influence on non-financial influence and experience of incubating organization has negative influence on non-financial performance without influence on financial performance. In addition, interaction of venture preparation period has positive influence solely between venture benefit and non-financial performance. Through this study, appropriate supporting plans depending on the level of venture preparation can be derived to improve business performance of initial venture foundations for policy designer of venture support, and quality rather than quality improvement of venture businesses is possible through investigation of structural issues of individual venture businesses. Ultimately, this study suggests venture founders to determine whether to focus on venture preparation process or to start a venture business.

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Conversion of an Anaerobic Digester to Thermophilic Range (혐기성소화조(嫌氣性消和槽)의 고온(高溫)에로의 전환(轉換))

  • Chang, Duk;Chung, Tai Hak
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.6 no.4
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    • pp.21-28
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    • 1986
  • Conversion of anaerobic mesophilic digestion to thermophilic range has been investigated using a synthetic sludge. When temperature was raised at a rate of 2, 1, and $0.5^{\circ}C$ per day with continuous feeding, a lower reaction rate was observed with a high rate of temperature change. Although methane fermentation ceased completely for an digesters at thermophilic temperature, acid fermentation continued. Methane fermentation was never achieved even with neutralization during 6 months of resting. The methane formers were completely inactivated by the temperature shock and accumulation of volatile acids due to continuous feeding, while the acid formers lost biological activity quickly, but gradually acclimated to a high temperature. When temperature was raised without feeding, successful thermophilic digestion was achieved with 1 day of resting at thermophilic temperature at a rate of $1^{\circ}C$ per day, and also achieved with 20 days of resting at a direct increase. Conversion to a thermophilic range is easily achieved with resting. A short period of resting is required at a low rate of temperature increase, while a long period of resting enough to balance methane formers with acid fermers makes a conversion possile when temperature is raised at a high rate. Soured thermophilic digesters were recovered after seeding of mesophilic sludges, and sludge seeding could be a good method of start-up, conversion, or recovery of a thermophilic digester. Significant amount of thermophiles seemed to be present in the mesophilic digesters.

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