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Effects of Personal Characteristics, Business Capabilities and Start-up Motivation on Start-up Satisfaction: Focusing on the Moderating Effect of Venture Startups and General Startups (개인특성, 사업역량 및 창업동기가 창업만족도에 미치는 영향 : 벤처창업기업과 일반창업기업의 차이를 중심으로)

  • Kim, Hyong-sok;Chung, Byoung-gyu
    • Journal of Venture Innovation
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    • v.6 no.1
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    • pp.35-57
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    • 2023
  • The purpose of this study was to analyze the moderating effect of venture start-up and general start-up based on what kinds of entrepreneurs' personal characteristics, business capabilities, and start-up motivation factors affecting start-up satisfaction. This study conducted an online survey of companies who received credit guarantee for start-ups from KCGF(Korea Credit Guarantee Fund), and finally collected 320 survey data. And it conducted statistical analyses such as frequency analysis, factor analysis, reliability analysis, correlation analysis, regression analysis, etc. using SPSS 24.0 statistics program. The results of the study were as follows. First, it is tested that creativity, one of entrepreneurs' characteristics, had a positive effect(+) on start-up satisfaction. Second, it is found that the failure burden, one of entrepreneurs' characteristics, had a negative effect(-) on start-up satisfaction. Third, experiences, one of entrepreneurs' characteristics, had not a significant effect on start-up satisfaction. Fourth, it was analyzed that business capabilities such as technology research and development, marketing, networking, and financing had a positive effect(+) on start-up satisfaction. Fifth, it is tested that the economic and self-realization motivation had a positive effect(+) on start-up satisfaction. Sixth, start-up satisfaction had a positive effect(+) on business performances. Last, it was analyzed that venture start-ups had a more positive effect than general start-up in the creativity, technology research and development, and the self-realization of start-up motivation affecting start-up satisfaction. And, it was found that venture start-ups have a less negative effect than general start-up in the failure burden affecting start-up satisfaction.

A Study on the Impact of SNS Usage Characteristics, Characteristics of Loan Products, and Personal Characteristics on Credit Loan Repayment (SNS 사용특성, 대출특성, 개인특성이 신용대출 상환에 미치는 영향에 관한 연구)

  • Jeong, Wonhoon;Lee, Jaesoon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.5
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    • pp.77-90
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    • 2023
  • This study aims to investigate the potential of alternative credit assessment through Social Networking Sites (SNS) as a complementary tool to conventional loan review processes. It seeks to discern the impact of SNS usage characteristics and loan product attributes on credit loan repayment. To achieve this objective, we conducted a binomial logistic regression analysis examining the influence of SNS usage patterns, loan characteristics, and personal attributes on credit loan conditions, utilizing data from Company A's credit loan program, which integrates SNS data into its actual loan review processes. Our findings reveal several noteworthy insights. Firstly, with respect to profile photos that reflect users' personalities and individual characteristics, individuals who choose to upload photos directly connected to their personal lives, such as images of themselves, their private circles (e.g., family and friends), and photos depicting social activities like hobbies, which tend to be favored by individuals with extroverted tendencies, as well as character and humor-themed photos, which are typically favored by individuals with conscientious traits, demonstrate a higher propensity for diligently repaying credit loans. Conversely, the utilization of photos like landscapes or images concealing one's identity did not exhibit a statistically significant causal relationship with loan repayment. Furthermore, a positive correlation was observed between the extent of SNS usage and the likelihood of loan repayment. However, the level of SNS interaction did not exert a significant effect on the probability of loan repayment. This observation may be attributed to the passive nature of the interaction variable, which primarily involves expressing sympathy for other users' comments rather than generating original content. The study also unveiled the statistical significance of loan duration and the number of loans, representing key characteristics of loan portfolios, in influencing credit loan repayment. This underscores the importance of considering loan duration and the quantity of loans as crucial determinants in the design of microcredit products. Among the personal characteristic variables examined, only gender emerged as a significant factor. This implies that the loan program scrutinized in this analysis does not exhibit substantial discrimination based on age and credit scores, as its customer base predominantly consists of individuals in their twenties and thirties with low credit scores, who encounter challenges in securing loans from traditional financial institutions. This research stands out from prior studies by empirically exploring the relationship between SNS usage and credit loan repayment while incorporating variables not typically addressed in existing credit rating research, such as profile pictures. It underscores the significance of harnessing subjective, unstructured information from SNS for loan screening, offering the potential to mitigate the financial disadvantages faced by borrowers with low credit scores or those ensnared in short-term liquidity constraints due to limited credit history a group often referred to as "thin filers." By utilizing such information, these individuals can potentially reduce their credit costs, whereas they are supposed to accrue a more substantial financial history through credit transactions under conventional credit assessment system.

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The Influence of Self-Leadership of Research and Development Practitioners on Innovative Behavior via Job Satisfaction : A Comparison between Manufacturing and ICT Industries (국내 기업 연구개발 종사자의 셀프리더십이 직무만족을 매개로 혁신행동에 미치는 영향 : 제조업과 정보통신업 비교)

  • Choi, Min-seog;Hwang, Chan-gyu
    • Journal of Venture Innovation
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    • v.7 no.1
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    • pp.91-110
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    • 2024
  • In this study, we compared and analyzed the influence of self-leadership on innovative behavior and the mediating effect of job satisfaction among R&D practitioners in manufacturing and information communication technology (ICT) industries. To accomplish this, we conducted an online survey using random sampling methods and collected data from 209 respondents. We employed exploratory factor analysis, reliability analysis, correlation analysis, multiple regression analysis, and mediation analysis using SPSS 20.0 software to analyze the data and to compare differences between the manufacturing and ICT sectors. The research findings are as follows: Firstly, both in manufacturing and ICT sectors, self-leadership showed significant positive correlations with job satisfaction and innovative behavior. Secondly, in the analysis of the impact of self-leadership on innovative behavior, in the manufacturing sector, only natural reward strategy and constructive thought strategy showed significant positive effects, while in the ICT sector, behavioral-oriented strategy, natural reward strategy, and constructive thought strategy all showed significant positive effects. Thirdly, in the analysis of the impact of self-leadership on job satisfaction, in the manufacturing sector, only natural reward strategy and constructive thought strategy showed significant positive effects, while in the ICT sector, behavioral-oriented strategy and natural reward strategy showed significant positive effects. Fourthly, in the analysis of the impact of job satisfaction on innovative behavior, significant positive effects were observed in both manufacturing and ICT sectors, with manufacturing sector having relatively greater impact than ICT sector. Lastly, the results of the analysis on the mediating effect of job satisfaction indicate that in the manufacturing sector, only a constructive thinking strategy significantly influences, showing partial mediating effects. However, in the ICT sector, no mediating effects of job satisfaction were observed for any sub-factors of self-leadership. These research findings highlight differences in the mechanisms of action of self-leadership on innovative behavior and its mediating effects between the manufacturing and ICT sectors. Furthermore, the results suggest the importance of improving organizational strategies and culture towards promoting leadership, job design, and job satisfaction, considering the characteristics of each industry and research and development organization.

Modeling of Estimating Soil Moisture, Evapotranspiration and Yield of Chinese Cabbages from Meteorological Data at Different Growth Stages (기상자료(氣象資料)에 의(依)한 배추 생육시기별(生育時期別) 토양수분(土壤水分), 증발산량(蒸發散量) 및 수량(收量)의 추정모형(推定模型))

  • Im, Jeong-Nam;Yoo, Soon-Ho
    • Korean Journal of Soil Science and Fertilizer
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    • v.21 no.4
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    • pp.386-408
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    • 1988
  • A study was conducted to develop a model for estimating evapotranspiration and yield of Chinese cabbages from meteorological factors from 1981 to 1986 in Suweon, Korea. Lysimeters with water table maintained at 50cm depth were used to measure the potential evapotranspiration and the maximum evapotranspiration in situ. The actual evapotranspiration and the yield were measured in the field plots irrigated with different soil moisture regimes of -0.2, -0.5, and -1.0 bars, respectively. The soil water content throughout the profile was monitored by a neutron moisture depth gauge and the soil water potentials were measured using gypsum block and tensiometer. The fresh weight of Chinese cabbages at harvest was measured as yield. The data collected in situ were analyzed to obtain parameters related to modeling. The results were summarized as followings: 1. The 5-year mean of potential evapotranspiration (PET) gradually increased from 2.38 mm/day in early April to 3.98 mm/day in mid-June, and thereafter, decreased to 1.06 mm/day in mid-November. The estimated PET by Penman, Radiation or Blanney-Criddle methods were overestimated in comparison with the measured PET, while those by Pan-evaporation method were underestimated. The correlation between the estimated and the measured PET, however, showed high significance except for July and August by Blanney-Criddle method, which implied that the coefficients should be adjusted to the Korean conditions. 2. The meteorological factors which showed hgih correlation with the measured PET were temperature, vapour pressure deficit, sunshine hours, solar radiation and pan-evaporation. Several multiple regression equations using meteorological factors were formulated to estimate PET. The equation with pan-evaporation (Eo) was the simplest but highly accurate. PET = 0.712 + 0.705Eo 3. The crop coefficient of Chinese cabbages (Kc), the ratio of the maximum evapotranspiration (ETm) to PET, ranged from 0.5 to 0.7 at early growth stage and from 0.9 to 1.2 at mid and late growth stages. The regression equation with respect to the growth progress degree (G), ranging from 0.0 at transplanting day to 1.0 at the harvesting day, were: $$Kc=0.598+0.959G-0.501G^2$$ for spring cabbages $$Kc=0.402+1.887G-1.432G^2$$ for autumn cabbages 4. The soil factor (Kf), the ratio of the actual evapotranspiration to the maximum evapotranspiration, showed 1.0 when the available soil water fraction (f) was higher than a threshold value (fp) and decreased linearly with decreasing f below fp. The relationships were: Kf=1.0 for $$f{\geq}fp$$ Kf=a+bf for f$$I{\leq}Esm$$ Es = Esm for I > Esm 6. The model for estimating actual evapotranspiration (ETa) was based on the water balance neglecting capillary rise as: ETa=PET. Kc. Kf+Es 7. The model for estimating relative yield (Y/Ym) was selected among the regression equations with the measured ETa as: Y/Ym=a+bln(ETa) The coefficients and b were 0.07 and 0.73 for spring Chinese cabbages and 0.37 and 0.66 for autumn Chinese cabbages, respectively. 8. The estimated ETa and Y/Ym were compared with the measured values to verify the model established above. The estimated ETa showed disparities within 0.29mm/day for spring Chinese cabbages and 0.19mm/day for autumn Chinese cabbages. The average deviation of the estimated relative yield were 0.14 and 0.09, respectively. 9. The deviations between the estimated values by the model and the actual values obtained from three cropping field experiments after the completion of the model calibration were within reasonable confidence range. Therefore, this model was validated to be used in practical purpose.

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The Patterns of Change in Arterial Oxygen Saturation and Heart Rate and Their Related Factors during Voluntary Breath holding and Rebreathing (자발적 호흡정지 및 재개시 동맥혈 산소포화도와 심박수의 변동양상과 이에 영향을 미치는 인자)

  • Lim, Chae-Man;Kim, Woo-Sung;Choi, Kang-Hyun;Koh, Youn-Suck;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.4
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    • pp.379-388
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    • 1994
  • Background : In sleep apnea syndrome, arterial oxygen saturation($SaO_2$) decreases at a variable rate and to a variable degree for a given apneic period from patient to patient, and various kinds of cardiac arrythmia are known to occur. Factors supposed to affect arterial oxygen desaturation during apnea are duration of apnea, lung voulume at which apnea occurs, and oxygen consumption rate of the subject. The lung serves as preferential oxygen source during apnea, and there have been many reports related with the influence of lung volume on $SaO_2$ during apnea, but there are few, if any, studies about the influence of oxygen consumption rate of an individual on $SaO_2$ during breath holding or about the profile of arterial oxygen resaturation after breathing resumed. Methods : To investigate the changes of $SaO_2$ and heart rate(HR) during breath holding(BH) and rebreathing(RB) and to evaluate the physiologic factors responsible for the changes, lung volume measurements, and arterial blood gas analyses were performed in 17 healthy subjects. Nasal airflow by thermistor, $SaO_2$ by pulse oxymeter and ECG tracing were recorded on Polygraph(TA 4000, Gould, U.S.A.) during voluntary BH & RB at total lung capacity(TLC), at functional residual capacity(FRC) and at residual volume(RV), respectively, for the study subjects. Each subject's basal metabolic rate(BMR) was assumed on Harris-Benedict equation. Results: The time needed for $SaO_2$ to drop 2% from the basal level during breath holding(T2%) were $70.1{\pm}14.2$ sec(mean${\pm}$standard deviation) at TLC, $44.0{\pm}11.6$ sec at FRC, and $33.2{\pm}11.1$ sec at RV(TLC vs. FRC, p<0.05; FRC vs. RV, p<0.05). On rebreathing after $SaO_2$ decreased 2%, further decrement in $SaO_2$ was observed and it was significantly greater at RV($4.3{\pm}2.1%$) than at TLC($1.4{\pm}1.0%$)(p<0.05) or at FRC($1.9{\pm}1.4%$)(p<0.05). The time required for $SaO_2$ to return to the basal level after RB(Tr) at TLC was not significantly different from those at FRC or at RV. T2% had no significant correlation either with lung volumes or with BMR respectively. On the other hand, T2% had significant correlation with TLC/BMR(r=0.693, p<0.01) and FRC/BMR (r=0.615, p<0.025) but not with RV/BMR(r=0.227, p>0.05). The differences between maximal and minimal HR(${\Delta}HR$) during the BH-RB manuever were $27.5{\pm}9.2/min$ at TLC, $26.4{\pm}14.0/min$ at RV, and $19.1{\pm}6.0/min$ at FRC which was significantly smaller than those at TLC(p<0.05) or at RV(p<0.05). The mean difference of 5 p-p intervals before and after RB were $0.8{\pm}0.10$ sec and $0.72{\pm}0.09$ sec at TLC(p<0.001), $0.82{\pm}0.11$ sec and $0.73{\pm}0.09$ sec at FRC(p<0.025), and $0.77{\pm}0.09$ sec and $0.72{\pm}0.09$ sec at RV(p<0.05). Conclusion Healthy subjects showed arterial desaturation of various rates and extent during breath holding at different lung volumes. When breath held at lung volume greater than FRC, the rate of arterial desaturation significantly correlated with lung volume/basal metabolic rate, but when breath held at RV, the rate of arterial desaturation did not correlate linearly with RV/BMR. Sinus arrythmias occurred during breath holding and rebreathing manuever irrespective of the size of the lung volume at which breath holding started, and the amount of change was smallest when breath held at FRC and the change in vagal tone induced by alteration in respiratory movement might be the major responsible factor for the sinus arrythmia.

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Clinical Analysis According to $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ Expression in Gastric Cancer (위암에서의 $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ 단백 발현)

  • Kim, Sin-Sun;Park, Yong-Geun;Jun, Kyong-Hwa;Jung, Hun;Song, Gyo-Young;Kim, Jin-Joo;Chin, Hyung-Min;Kim, Wook;Park, Cho-Hyun;Park, Seung-Man;Lim, Keun-Woo;Kim, Seung-Nam;Jeon, Hae-Myung
    • Journal of Gastric Cancer
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    • v.6 no.1
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    • pp.36-42
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    • 2006
  • Purpose: The $p21^{Waf1/Cip1}$ protein Inhibits the cell cycle by Inhibiting the phosphorylation at the $G1{\rightarrow}S$ check point, and the $p27^{kip1}$ protein similarly performs the suppressor function by controlling the p27-mediated G1 arrest. In this study, we analysed the clinical status and survival rates in correlations with p21 and p27 expression patterns in gastric cancer. Materials and Methods: Between 1993 and 1997, 192 patients who underwent surgeries in Catholic Medical Center were analysed retrospectively in this study. Immunohistochemical staining was performed and if the nuclei of the tumor cells were stained, we assumed those as positive results. Statistical analysis was based on clinicopathological findings and differences in survival rates. Results: The expression rate of p27 was 28.1% and 15.6% in p21 each. The ratio of T1-2(80.0%) was significantly high in p21 (+), but the ratio of T3-4 (50.6%) was slightly high in p21 (-). There was no statistical significance regarding other factors. The results in p27 was not much different from expression rate of p21 in T-stage. In addition, p27 expression in diffuse type (91.3%) was higher than in intestinal type (62.7%) by Lauren's classification (P<0.05). Also, there was no statistical significance in other factors. In the correlation of p21 and p27, p27 was positive when p21 was positive (53.5%). Conversely, p27 was negative when p21 was negative (76.5%, p<0.05). In the p21 and p27 combination test, there was higher rate of T1-2 (87.5%) in p21 (+)/p27 (+), and higher rate of T3-4 (58.1%) in p21 (-)/p27 (-) (P<0.05). Results showed higher rate of intestinal type (100%) in p21 (+)/p27 (+), and diffuse type (87.0%) was dominant in p21 (-)/p27 (-) (P<0.05) by Lauren's classification. Moreover, there was no statistical significance in the 5-year survival rate in the expression of p21 and p27, and the 5-year survival rate was highest in the case of p21 (+)/p27 (+) without statistical significance. Conclusion: In our study, $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ expressed similar patterns. The expression of $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ affected the degree of invasiveness of the tumor, and. Combined examination result revealed the correlation of $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ with Lauren's classification and depth of invasion of the tumor. However, we assumed that little difference between the survival rates depending on expression of $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ has limited their value as predictable prognostic indicators.

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한국 청소년의 약물남용과 비행행위

  • 김성이
    • Korea journal of population studies
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    • v.11 no.2
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    • pp.54-66
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    • 1988
  • I. Introduction Since the 1970's drug abuse among young people has increasingly become a social problem in Korea. In the 1980's, drug abuse, especially glue sniffing, has become the cause of many unfortunated incidents resulting in harm to others as well as the abusers themselves. Taking into consideration of the seriousness of this problem, the Republic of Korea National Red Cross initiated a nation-wide research programme, to understand the present situation and to raise the level of public awareness. The goal of this research was to begin a nation - wide campaign against drug abuse. The research team was composed of the Advisary Committee members and the staff of the Youth Department of the Republic of Korea National Red Cross. The data were collected in February 1988 with the collaboration of the staff and volunteers in the local Chapters. The respondents were allocated nation-wide by the quota sampling method. The questionnaires were distributed to the respondents in three groups :2, 700 to junior and senior high school students, 605 to working youths, and 916 to delinquent youths. A total of 4, 221 questionnaires were collected. II. Characteristics of the Respondents The respondents in each group were selected evenly from rural and urban areas. The general characteristics of the respondents can be described as follow: in case of students, the proportions between male and female respondents, and between senior high school and junior high school students were almost evenly distributed. In case of working youths, the proportion of females (80.5%) was higher than those of the students and the delinquents groups. Delinquent youths were defined as those currently being under custody of the centers for juvenile delinquents. Of this number, 38.8% and 68.2% were junior and senior high school drop-outs respectively. The majority of them (92.6%) were male. As for the family background of the respondents, the proportion of those residing in poverty - stricken areas, and the proportion of those from broken families were higher in case of working youths and delinquent youths than those in case of students. III. Present Patterns of Drug Abuse The following summarizes the presents of drug abuse, as tabulated from the results of the survey. 1. Smoking The percentage of youths who smoke was 36% in the student group, 32% m the working youths group, and 94.4% in the delinquent youths group. 2. Alcohol 50.3% of students, 71.6% of working youths, and 93.3% of delinquent youths has experienced drinking alcohol beverages. 3. Tonic: non - alcoholic, caffeinated beverages popular in Korea and Japan The percentage of those who have used tonic at least once was over 90% in all of the three groups. 4. Sedative About 70% of each group has used sedative with the proportion of working youths use higher than those in other groups. 5. Stimulants Those who have used stimulants comprised around 15% in each group. 6. Tranquilizers Somewhat less than 5% of students and working youths, and 28% of delinquent youths, have used tranquilizers. 7. Hypnotics The users of hypnotics amounted to 0.4% of students, 2.6% of working youths and 7.1% of delinquent youths. 8. Marihuana Those who have used marihuana indicated 0.7% of students, 0.8% of working youths, and 13% of delinquent youths. 9. Glue-sniffing The percentage of glue-sniffing was 3.7%, 5% in the students group and in the youths group respectively, but the proportion was unusually high, at 40.7% in the delinquent youths group. From the results of the survey the present situation of drug abuse in Korea can be summarized as follows: 1. A high percentage of Korean youths have experienced smoking cigarettes and drinking alcoholic beverages. 2. Tonics (non - alcoholic, caffeinated beverages), antipyretic analgesics and stimulants quite regularly used. 3. Tranquilizers, hypnotics, marihuana and glue-sniffing are more widely used among delinquent youths than the other youths. From this fact, there exists a correlation between drug abuse and juvenile delinquency. IV. Time-series Analysis of the First Experience of Drug Abuse and Deviant Behaviour The respoundents were asked when they were first exposed to drugs and when they committed deviant acts. By calculating the average age of each experience, the following pattern was found (See Figure 1). Youths are first exposed to drugs by abuse of tonic(non - alcoholic, caffeinated beverages). At the age of 13, they amoke cigarettes, the use of antipyretic analgesics begins at 14 year old, while at the age of 15, they use tranquilizers, and at 16 hynotics. The period of drug abuse which starts from drinking caffeinated beverages and smoking cigarettes and ends in the use of hypnotics takes about three years. During this period, other delinquent behaviours begin to surface, that is, at the age of 13 when smoking cigarettes begins, the delinquent behaviour pattern starts with truancy. Next, they start taking money from others by using physical force. Prior to the age of 15, they are suspended from school, become hostile to adults, begin running away from home, and start using stimulants and alcohol. Soon they become involved even in glue-sniffing and in the use of marihuana. At the age of 15, they begin to see adult videos and carry weapons. Sexual promiscuity and usage of tranquilizers follows the viewing of adult videos. Consequently, by the time they reach the age of 16, they visit drinking establishments, and are picked up by police for committing delinquent acts. And finally, they come to use hypnotic - type drugs. From the above descriptions, drug abuse can be assumed to have a close correlation with delinquent behaviour. V. Social Factors Related to Drug Abuse As for the Korean youths, glue-sniffing is found to he related to aggressive delinquency, in such cases as run - aways, being picked up by the police, and taking money by force. Smoking cigarettes and drinking alcohol is found to be related to seeing adult videos and visiting drinking establishments. Hypnotics and marihuana were found to be representive of drugs which are related to degenerational delinquency, irrespective of social delinquency. The social factors connected with these drug abuse are as follows: 1. Individual factors Male students were more heavily involved in the usage of drug than females. Youths who do not attend church were more likely to be involved in drugs than those who attend. 2. Family factors The youths who were displeased with their mothers smoking and those who thought their parents did not love each other, or those whose parents had used drugs without prescription, were more likely to he drug users. 3. School factors Those youths who found school life boring, were unsuccessful in their studies, spend most of their time with friends, feel their teachers smoke too much, those who had a positive perception of their teachers smoking were likely to he drug users. To sum up, drug abusers depend on the influence of their parents, teachers and peers. IV. Reasons for Drug Abuse Korean students have mainly used drugs to release stress (42.8%), to stay awake (19.7%), and because of the easy accessibility of drugs( 16.6%). Other reasons are due to their ignorance of the side effects of the drugs (3.6%), natural curiosity (4.2%), and to increase strength(3.O%). From the above facts, the major reasons for drug abuse among Korean youths are to release stress and to stay awake in order to prepare exams. Furthermore, since drugs are readily available, we can conclude that drug abuse is caused by the school system(such as entrance exams) in Korea. VII. Conclusion Drug usage among Korean youths are relatively less common than those of western youths. In some cases, such as, glue-sniffing and use of stimulants, the pattern of drug abuse is found. Moreover, early drug abuse is evident, and it has a close connection with deviant behaviour, resulting in juvenile delinquency. Drug abuse cannot be attributed to any one social factor. Specifically, drug abuse depends on parents, peers, teachers and other members of the community, and also is influenced by social institutions such as the entrance exam system. Every person and organization concerned with youth must participate collectively in restraining drug abuse. Finally, it is suggested that social agencial working for youth welfare should make every effort to tackle this serious problem confronted by the Korean youths today.

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Correlation of p53 Protein Overexpression, Gene Mutation with Prognosis in Resected Non-Small Cell Lung Cancer(NSCLC) Patients (비소세포폐암에서 p53유전자의 구조적 이상 및 단백질 발현이 예후에 미치는 영향)

  • Lee, Y.H.;Shin, D.H.;Kim, J.H.;Lim, H.Y.;Chung, K.Y.;Yang, W.I.;Kim, S.K.;Chang, J.;Roh, J.K.;Kim, S.K.;Lee, W.Y.;Kim, B.S.;Kim, B.S.
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.4
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    • pp.339-353
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    • 1994
  • Background : The p53 gene codes for a DNA-binding nuclear phosphoprotein that appears to inhibit the progression of cells from the G1 to the S phase of the cell cycle. Mutations of the p53 gene are common in a wide variety of human cancers, including lung cancer. In lung cancers, point mutations of the p53 gene have been found in all histological types including approximately 45% of resected NSCLC and even more frequently in SCLC specimens. Mutant forms of the p53 protein have transforming activity and interfere with the cell-cycle regulatory function of the wild-type protein. The majority of p53 gene mutations produce proteins with altered conformation and prolonged half life; these mutant proteins accumulate in the cell nucleus and can be detected by immunohistochemical staining. But protein overexpression has been reported in the absence of mutation. p53 protein overexpression or gene mutation is reported poor prognostic factor in breast cancer, but in lung cancer, its prognostic significance is controversial. Method : We investigated the p53 abnormalities by nucleotide sequencing, polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP), and immunohistochemical staining. We correlated these results with each other and survival in 75 patients with NSCLC resected with curative intent. Overexpression of the p53 protein was studied immunohistochemically in archival paraffin- embedded tumor samples using the D07(Novocastra, U.K.) antibody. Overexpression of p53 protein was defined by the nuclear staining of greater than 25% immunopositive cells in tumors. Detection of p53 gene mutation was done by PCR-SSCP and nucleotide sequencing from the exon 5-9 of p53 gene. Result: 1) Of the 75 patients, 36%(27/75) showed p53 overexpression by immunohistochemical stain. There was no survival difference between positive and negative p53 immunostaining(overall median survival of 26 months, disease free median survival of 13 months in both groups). 2) By PCR-SSCP, 27.6%(16/58) of the patients showed mobility shift. There was no significant difference in survival according to mobility shift(overall median survival of 27 in patients without mobility shift vs 20 months in patients with mobility shift, disease free median survival of 8 months vs 10 months respectively). 3) Nucleotide sequence was analysed from 29 patients, and 34.5%(10/29) had mutant p53 sequence. Patients with the presence of gene mutations showed tendency to shortened survival compared with the patients with no mutation(overall median survival of 22 vs 27 months, disease free median survival of 10 vs 20 months), but there was no statistical significance. 4) The sensitivity and specificity of immunostain based on PCR-SSCP was 67.0%, 74.0%, and that of the PCR-SSCP based on the nucleotide sequencing was 91.8%, 96.2% respectively. The concordance rate between the immunostain and PCR-SSCP was 62.5%, and the rate between the PCR-SSCP and nucleotide sequencing was 95.3%. Conclusion : In terms of detection of p53 gene mutation, PCR-SSCP was superior to immunostaining. p53 gene abnormalities either overexpression or mutation were not a significant prognostic factor in NSCLC patients resected with curative intent. However, patients with the mutated p53 gene showed the trends of early relapse.

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The Influence of Ventilation and Shade on the Mean Radiant Temperature of Summer Outdoor (통풍과 차양이 하절기 옥외공간의 평균복사온도에 미치는 영향)

  • Lee, Chun-Seok;Ryu, Nam-Hyung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.5
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    • pp.100-108
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    • 2012
  • The purpose of the study was to evaluate the influence of shading and ventilation on Mean Radiant Temperature(MRT) of the outdoor space at a summer outdoor. The Wind Speed(WS), Air Temperature(AT) and Globe Temperature(GT) were recorded every minute from $1^{st}$ of May to the $30^{th}$ of September 2011 at a height of 1.2m above in four experimental plots with different shading and ventilating conditions, with a measuring system consisting of a vane type anemometer(Barini Design's BDTH), Resistance Temperature Detector(RTD, Pt-100), standard black globe(${\O}$ 150mm) and data acquisition systems(National Instrument's Labview and Compfile Techs' Moacon). To implement four different ventilating and shading conditions, three hexahedral steel frames, and one natural plot were established in the open grass field. Two of the steel frames had a dimension of $3m(W){\times}3m(L){\times}1.5m(H)$ and every vertical side covered with transparent polyethylene film to prevent lateral ventilation(Ventilation Blocking Plot: VP), and an additional shading curtain was applied on the top side of a frame(Shading and Ventilation Blocking Plot: SVP). The third was $1.5m(W){\times}1.5m(L){\times}1.5m(H)$, only the top side of which was covered by the shading curtain without the lateral film(Shading Plot: SP). The last plot was natural condition without any kind of shading and wind blocking material(Natural Open Plot: NP). Based on the 13,262 records of 44 sunny days, the time serial difference of AT and GT for 24 hour were analyzed and compared, and statistical analysis was done based on the 7,172 records of daytime period from 7 A.M. to 8 P.M., while the relation between the MRT and solar radiation and wind speed was analyzed based on the records of the hottest period from 11 A.M. to 4 P.M.. The major findings were as follows: 1. The peak AT was $40.8^{\circ}C$ at VP and $35.6^{\circ}C$ at SP showing the difference about $5^{\circ}C$, but the difference of average AT was very small within${\pm}1^{\circ}C$. 2. The difference of the peak GT was $12^{\circ}C$ showing $52.5^{\circ}C$ at VP and $40.6^{\circ}C$ at SP, while the gap of average GT between the two plots was $6^{\circ}C$. Comparing all four plots including NP and SVP, it can be said that the shading decrease $6^{\circ}C$ GT while the wind blocking increase $3^{\circ}C$ GT. 3. According to the calculated MRT, the shading has a cooling effect in reducing a maximum of $13^{\circ}C$ and average $9^{\circ}C$ MRT, while the wind blocking has heating effect of increasing average $3^{\circ}C$ MRT. In other words, the MRT of the shaded area with natural ventilation could be cooler than the wind blocking the sunny site to about $16^{\circ}C$ MRT maximum. 4. The regression and correlation tests showed that the shading is more important than the ventilation in reducing the MRT, while both of them do an important role in improving the outdoor thermal comfort. In summary, the results of this study showed that the shade is the first and the ventilation is the second important factor in terms of improving outdoor thermal comfort in summer daylight hours. Therefore, it can be apparently said that the more shade by the forest, shading trees etc., the more effective in conditioning the microclimate of an outdoor space reducing the useless or even harmful heat energy for human activities. Furthermore, the delicately designed wind corridor or outdoor ventilation system can improve even the thermal environment of urban area.

Effects of Evaporative Water-loss from Cultural Pots on Growth of Pot-grown Ornamental Plants (화분(花盆)의 수분증발(水分蒸發)이 분식화훼류(盆植花卉類)의 생육(生育)에 미치는 영향(影響))

  • Suh, Youn-gkyo
    • Korean Journal of Agricultural Science
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    • v.4 no.2
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    • pp.317-343
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    • 1977
  • This study was carried out to obtain the informations about evaporation from pot, soil temperature and soil atmosphere composition in pot, and the effect on the growth of nine ornamental species using seven different containers. The investigated containers were clay pot(CP), clay pot painted in green(CP-P), varnished clay pot(CP-V), polyethylene film inserting in clay pot(CP-PI), clay pot mulched with black polyethylene film(CP-PM), porcelain pot(POP), and plastic pot(PLP). Nine ornamental species were balsam(Impatiens balsamina), chrysanthemum(Chrysanthemum morifolium), cosmos(Cosmos bipinatus), English ivy(Hedera helix), geranium(Pelargonium zonale), kochia(Kochia scoparia var. trichophila), marigold(Tagetes patula), ornamental kale(Brassica oleraceae var. acephala), and salvia (Salvia splendens). The results obtained are summarized as follows: 1. Dry weight of all tested species grown in PLP, POP, CP-P, CP-V and CP-PI was heavier than that of CP. 2. Plant height in nine tested species grown in PLP, POP, CP-P, CP-V, and CP-PI was taller than that of CP. 3. Geranium grown in PLP, POP, CP-P, and CP-V gave more number of leaf than that of CP. 4. The number of flower in balsam grown in PLP, POP, CP-P, CP-V and CP-PI was more than that of CP. The result from marigold was very similar to this tendency. Spike length and floret number in salvia gave the same tendency, but its spike number was not different among containers used. 5. The average diurnal evaporation from PLP and POP was about 43% of that of CP. About two third of total evaporation from CP was through pot wall. 6. The evaporation rate from the slowest to the highest was PLP, POP, CP-P, CP-V, CP-PI, CP-PM and CP. Containers inhibiting evaporation through pot wall hold more soil moisture than CP from one day after water supply. 7. The more evaporative water-loss from containers gave the lower soil temperature. The variation of soil temperature among containers was higher during the day than the night. 8. The $O_2$ concentration of soil atmosphere in CP was higher than that of nonporous containers, and the difference between them was 0.40-1.12%. The range of the $O_2$ concentration 17.95~19.62%. The $CO_2$ concentration of soil atmosphere in CP was lower than that of nonporous containers, and its range was 0.59-1.76%. This deviation in soil atmosphere composition did not influenced on the growth of plants. 9. There was a possitive correlation between the amount of soil water and the plant growth. 10. Plant grown on CP gave more total nitrogen content in top growth than that on PLP. C/N ratio was somewhat low in plant on CP. From the above results, $O_2$ and $CO_2$ concentration in soil atmosphere did not gave enough deviation to the extent which affect the plant growth. The effect of soil moisture on the plant growth using different containers was the far-most significant factor from this investigation. Therefore, it was obious that the utilization of the nonporous container might save the cost for water supply and reduce the production cost of the pot-grown ornamental plant in Korea eventually.

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