• Title/Summary/Keyword: Long Term Effects

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The Effects of The Distinction in Family Business on CEO Succession Types: A Behavioral Agency Theory Perspective (행동대리인 이론관점에서 가족기업 특성이 승계에 미치는 영향)

  • Kim, Ki-Hyung;Moon, Chul-Woo;Kim, Sang-kyun;Lee, Byung-Hee
    • Korean small business review
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    • v.39 no.1
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    • pp.1-39
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    • 2017
  • The first generation of the business that had been founded in 1960~1970s faces the situation to consider the succession of the family business developed by devotion of their whole lives in the critical timing to the next generation. In the process of selecting the party of family business succession, it is required to consider a variety of succession types including smooth transfer to the other family member or the employee of the company, selling the company, or hiring external specialist. Foreign countries acknowledge the importance of the succession in the family owned company to perform multiple studies on the influential factors to the succession, distinction, and types of family business succession; and they utilize the results for the related policy development and the support of family owned business succession. However, few studies have been conducted on the succession of the domestic family owned business and majority of them are related to the types of succession. Considering its share and influential power in the domestic economy, it is necessary to develop the guideline and the policies to solve many issues on the succession of the family owned business by systemic studies. Hence, the impact of the main characteristics in the family owned business on the types of its succession was analyzed in this study focusing on five domains of Socioemtional Wealth (SEW) in view of Behavioral Agency Theory by Gomez-Mejia et al. (2007) using the data from 540 family owned small-to-medium sized businesses so as to analyze the issues on their business succession. Upon the empirical analysis results, it was confirmed that they were influenced to the selection of succession type by family succession > internal employee succession > external succession, for the variables of social contribution which were non-financial characteristics, internal employee succession > family succession > external succession for the intellectual properties, and family succession > external succession for the management participation of the family. The distinction of social contribution were influenced the most to the selection of the succession types. Financial factors, business performance, and R&D investment variables were not significantly influenced to their selection of the succession types. In case of simultaneous management, the family succession rate was high and it showed the control effect to strengthen selecting family owned business with R&D investment, social contribution, and company history variables. The behavioral agency theory used in this study was confirmed with high explanation power on the family owned business succession. The family owned business showed the tendency to maintain SEW, and non-financial factors such as accumulated know-how and social contribution based on the long term history were significantly affected to the succession in the small-to-medium sized family owned businesses, unlike general large sized listed companies. The results of this study are expected to be helpful practically for the succession of the family owned business and to suggest the guideline for the development of governmental policy.

Ammonia Decomposition over Ni Catalysts Supported on Zeolites for Clean Hydrogen Production (청정수소 생산을 위한 암모니아 분해 반응에서 Ni/Zeolite 촉매의 반응활성에 관한 연구)

  • Jiyu Kim;Kyoung Deok Kim;Unho Jung;Yongha Park;Ki Bong Lee;Kee Young Koo
    • Journal of the Korean Institute of Gas
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    • v.27 no.3
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    • pp.19-26
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    • 2023
  • Hydrogen, a clean energy source free of COx emissions, is poised to replace fossil fuels, with its usage on the rise. Despite its high energy content per unit mass, hydrogen faces limitations in storage and transportation due to its low storage density and challenges in long-term storage. In contrast, ammonia offers a high storage capacity per unit volume and is relatively easy to liquefy, making it an attractive option for storing and transporting large volumes of hydrogen. While NH3 decomposition is an endothermic reaction, achieving excellent low-temperature catalytic activity is essential for process efficiency and cost-effectiveness. The study examined the effects of different zeolite types (5A, NaY, ZSM5) on NH3 decomposition activity, considering differences in pore structure, cations, and Si/Al-ratio. Notably, the 5A zeolite facilitated the high dispersion of Ni across the surface, inside pores, and within the structure. Its low Si/Al ratio contributed to abundant acidity, enhancing ammonia adsorption. Additionally, the presence of Na and Ca cations in the support created medium basic sites that improved N2 desorption rates. As a result, among the prepared catalysts, the 15 wt%Ni/5A catalyst exhibited the highest NH3 conversion and a high H2 formation rate of 23.5 mmol/gcat·min (30,000 mL/gcat·h, 600 ℃). This performance was attributed to the strong metal-support interaction and the enhancement of N2 desorption rates through the presence of medium basic sites.

Effect of Organizational Support Perception on Intrinsic Job Motivation : Verification of the Causal Effects of Work-Family Conflict and Work-Family Balance (조직지원인식이 내재적 직무동기에 미치는 영향 : 일-가정 갈등 및 일-가정 균형의 인과관계 효과 검증)

  • Yoo, Joon-soo;Kang, Chang-wan
    • Journal of Venture Innovation
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    • v.6 no.1
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    • pp.181-198
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    • 2023
  • This study aims to analyze the influence of organizational support perception of workers in medical institutions on intrinsic job motivation, and to check whether there is significance in the mediating effect of work-family conflict and work-family balance factors in this process. The results of empirical analysis through the questionnaire are as follows. First, it was confirmed that organizational support recognition had a significant positive effect on work-family balance as well as intrinsic job motivation, and work-family balance had a significant positive effect on intrinsic job motivation. Second, it was confirmed that organizational support recognition had a significant negative effect on work-family conflict, but work-family conflict had no significant influence on intrinsic job motivation. Third, in order to reduce job stress for medical institution workers, it is necessary to reduce job intensity, assign appropriate workload for ability. And in order to improve manpower operation and job efficiency, Job training and staffing in the right place are needed. Fourth, in order to improve positive organizational support perception and intrinsic job motivation, It is necessary to induce long-term service by providing support and institutional devices to increase attachment to the current job and recognize organizational problems as their own problems with various incentive systems. The limitations of this study and future research directions are as follows. First, it is believed that an expanded analysis of medical institution workers nationwide by region, gender, medical institution, academic, and income will not only provide more valuable results, but also evaluate the quality of medical services. Second, it is necessary to reflect the impact of the work-life balance support system on each employee depending on the environmental uncertainty or degree of competition in the hospital to which medical institution workers belong. Third, organizational support perception will be recognized differently depending on organizational culture and organizational type, and organizational size and work characteristics, working years, and work types, so it is necessary to reflect this. Fourth, it is necessary to analyze various new personnel management techniques such as hospital's organizational structure, job design, organizational support method, motivational approach, and personnel evaluation method in line with the recent change in the government's medical institution policy and the global business environment. It is also considered important to analyze by reflecting recent and near future medical trends.

A Study on the Relationships Among Learning Orientation, Innovativeness and Organizational Commitment of Entrepreneurs: Focusing on the Mediating Effect of Innovativeness and the Moderating Effect of Career Relevance (학습지향성 및 혁신성과 조직몰입 간의 관계에 관한 연구: 혁신성의 매개효과와 경력연관성의 조절효과를 중심으로)

  • Joo-Heon, Lee
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.17 no.6
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    • pp.159-174
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    • 2022
  • Entrepreneurs should continuously invest resource and capital for a long time to get tangible business results. In order to be successful, despite difficulties, it is essential for entrepreneurs to continue entrepreneurial businesses without giving up too early. Thus, it can be said that organizational commitment of entrepreneurs is essential for success. According to previous studies, the organizational commitment of entrepreneurs has a significant effect on organizing, establishments of new firms and new product developments. The purpose of this article is to examine the relationships among learning orientation, innovativeness and organizational commitment of entrepreneurs. Especially, we focus on the mediating effect of innovativeness in the relationship between learning orientation and organizational commitment and the moderating effect of career relevance among the relationships. Based on empirical analysis, we reported the following results. First, learning orientation, innovativeness and career relevance of entrepreneurs had significant positive effects on organizational commitment. Second, it was found that innovativeness of entrepreneurs has a partial mediating effect on the relationship between learning orientation and organizational commitment. Third, using Baron & Kenny's hierarchical multiple regression analysis, we examined the moderating effect of career relevance among the relationships of learning orientation, innovativeness and organizational commitment. Third, because the interaction term was found to be positively significant, it was concluded there is a moderating effect of career relevance between learning orientation and innovativeness. This means, when career relevance was higher than average, the influence of learning orientation on innovation increases even more. Fourth, it was also found there is a moderating effect of career relevance between learning orientation and organizational commitment. However, the results of the mediated moderating effect analysis showed the moderating effect of career relevance between learning orientation and organization commitment is an indirect effect of moderating effect of career relevance between learning orientation and innovativeness mediated by innovativeness.

The Comparison of Efficacy and Safety between Radiofrequency Ablation Alone and Ethanol Ablation Followed by Radiofrequency Ablation in the Treatment of Mixed Cystic and Solid Thyroid Nodule (낭성 및 고형성 혼합 갑상선 결절 치료에서 고주파 절제술 단독요법과 에탄올 절제 후 고주파 절제술 요법의 유효성 및 안전성 비교)

  • Min Gang Jo;Min Kyoung Lee;Jae Ho Shin;Min Guk Seo;So Lyung Jung
    • Journal of the Korean Society of Radiology
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    • v.85 no.3
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    • pp.618-630
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    • 2024
  • Purpose To compare the efficacy and safety of radiofrequency ablation (RFA) and ethanol ablation (EA) followed by RFA in treating mixed cystic and solid thyroid nodules. Materials and Methods We included 243 nodules from 243 patients who underwent RFA for mixed cystic and solid benign nodules. The nodules were divided into two groups (RFA alone and EA + RFA). We evaluated volume reduction rate (VRR), therapeutic success rate, improvement in symptomatic and cosmetic issues, complications, and adverse effects. Results The RFA group included 204 patients, and the EA + RFA group included 39 patients. The long-term success rates in the RFA only and EA + RFA groups were 90.2% and 97.4%, respectively. The mean VRR at the last follow-up in the RFA and EA + RFA groups were 81.6% and 87.2%, respectively. Therapeutic results were similar in both groups at the last followup. Cosmetic and symptomatic problems markedly improved in both groups. No major complications were observed. Conclusion Both RFA alone and EA + RA are safe and effective methods for treating mixed cystic and solid thyroid nodules, although EA + RFA is slightly more effective.

Analysis of Physical Characteristics of Adolescent Weightlifters (중·고교 엘리트 역도선수들의 성장기 기초 및 전문체력 특성 변화)

  • Dong-Joo Hwang;Hyung-Jun Kim;In-A Park;Seung-Hyeon Lee;Joon-Yong Cho;Joo-Ha Jung
    • Journal of the Korean Applied Science and Technology
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    • v.41 no.3
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    • pp.813-824
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    • 2024
  • This study was conducted to evaluate the long-term effects of training on the physical development and exercise performance of adolescent weightlifters, aiming to provide effective training and management strategies for improving competitive performance. In order to achieve the objectives of the study, adolescent weightlifters from middle and high schools in Chungcheongnam-do province [male middle school-aged athletes, n=5; female middle school-aged athletes, n=5; male high school-aged athletes, n=12; female high school-aged athletes, n=8] were examined over approximately 10 months of weightlifting-based training to analyse the changes in body composition, physical fitness (muscular strength, muscular endurance, agility, flexibility, dynamic balance, coordination), and isokinetic muscular function (trunk and lower extremity). As a result, it was found that the physical development of middle and high school-aged athletes underwent physical development primarily characterized by an increase in lean body mass. Additionally, back muscle strength and power, which contribute to rapid and efficient force transmission between the upper and lower body, as well as grip strength necessary for controlling the barbell with a stable grip, are significant factors. These aspects were notably enhanced through specialized training and competitive experience for weightlifting performance at the high school level. On the other hand, changes in factors beyond the primary physical attributes contributing to weightlifting performance were limited, suggesting differences in effectiveness likely stemming from the specific composition of training programs or the athletes' experience and skill levels. Collectively, the findings from this study, which evaluates the physical characteristics and exercise abilities of adolescent weightlifters, are expected to contribute to improved competitive performance of weightlifters.

Effects of TR and Consumer Readiness on SST Usage Motivation, Attitude and Intention (기술 준비도와 소비자 준비도가 Self Service Technology 사용동기와 태도 및 사용의도에 미치는 영향)

  • Shim, Hyeon Sook;Han, Sang Lin
    • Asia Marketing Journal
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    • v.14 no.1
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    • pp.25-51
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    • 2012
  • Researches about the relationship between SST(Self Service Technology) and TRI(Technology Readiness Index) have been carried out after TRI was developed by Parasuraman and his colleagues(2000). We hypothesize Consumer Readiness can also influence consumer's motivation, attitude, and intent to use SST. Currently, there has been no research on this subject. In this study, we investigated the relationship between TR, Consumer Readiness and SST Core Attitudinal Model which Dabholkar & Bagozzi(1994) proposed. The researchers also investigated moderating effects of consumer traits and situational factors to verify the acceptance of such forms of service delivery by all kinds of consumers and under different situational contexts. Self consciousness, the need for interaction with an employee, and the technology anxiety were used as consumer trait variables. Perceived waiting time and perceived crowding were used as situational variables. 380 questionnaires were distributed to a sample group of people in their 20's and 30's, and the data were analyzed with structural equation model using AMOS 18.0 program. All of Cronbach's alpha values representing reliabilities were satisfactory. The values of Composite Reliability(CR) and Average Variance Extracted(AVE) also showed the above criteria, thus providing evidence of convergent validity. To confirm discriminant validity among the constructs, confirmatory factor analysis and correlations among all the variables were examined. The results were satisfactory. The results of this study are summarized as follows. 1. Optimism and innovativeness of TR partially influenced the motivation to use SST. People who tend to be optimistic use SST because of ease of use and fun. The innovative however, usually use SST due to its performance. However, consumer readiness of role clarity, ability and self-efficacy influence all the components of motivation to use SST, ease of use, performance and fun. The relative effect of consumer readiness on the motivation to use SST was much stronger and more significant than that of TR. No other previous studies have examined the effects of Consumer Readiness on SST usage motivation, attitude and intention. It is academically meaningful that the researchers verified that Consumer Readiness is the important precedent construct influencing the self service technology core Attitudinal Model. Our findings suggest that marketers should consider fun and ease of use attributes to promote the use of self service technology. In addition, the SST usage frequency will rise rapidly when role clarity, ability, and self-efficacy which anybody can easily handle SST is assured. If the SST usage rate is increased, waiting times for customers could be decreased. Shorter waiting time could lead to higher customer satisfaction. It may also result in making a long-term profit owing to the reduced number of employees. Thus, presentation of using SST by employees or videos showing how to use it will promote the usage attitude and intent. 2. In SST core attitudinal model, performance and fun factors among SST usage motivation affected attitudes of using SST. The attitude of using SST highly influenced intent to use SST. This result is consistent with previous researches that dealt with the relationship between motivation, attitude and intention. Expectation of using SST could result in good performance just like the effect of ordering menu to service employees and to have fun since fun during its use could promote more SST usage rate. 3. In the relationship among motivation, attitude and intent in SST core attitudinal model, the moderating effect of consumer traits(self-consciousness, need for interaction with service employees and technology anxiety) and situational factors(perceived crowding and perceived waiting time) were tested. The results also supported the hypothesized moderating effects except perceived crowding. The highly self-conscious tended to form attitudes to use SST because of its fun compared to those who were less self-conscious because of its performance. People who had a high need for interaction with service employees tended to use SST for its performance. This result indicates that if ordering results are assured, SST is easily accessible to even consumers who have a high need for interaction with a service employee. When SST is easy to use, attitudes strengthen intent among people who had a high level of anxiety of technology. People who had low technology anxiety formed attitudes to use SST because of its performance. Service firms must ensure their self service technology is designed to be easy to use for those who have a high level of technology anxiety. Shorter perceived waiting times strengthened the attitude to use self service technology because of its fun. If the fun aspect is assured, people willing to use self service technology even perceive waiting time to be shorter than it actually is. Greater perceived waiting times form higher level of intent to use self service technology than those of shorter perceived waiting times. This implies that people view self service technology as a faster alternative to ordering service employees. The fun aspect of self service technology will attract a higher rate of usage for self service technology. 4. It has been proven that ease of use, performance and fun aspects are very important factors in motivation to form attitudes and intent to use self service technology regardless of the amount of perceived waiting time, self-consciousness, need for interaction with service employees, and technology anxiety. Service firms must consider these motivation aspects(ease of use, performance and fun)strongly in their promotion to use self service technology. Ease of use, assuring absolute performance compared to interaction with service employees', and adding a fun aspect will positively strengthen consumers' attitudes and intent to use self service technology. Summarizing the moderating effects, fun is the most valuable factor triggering SST usage attitude and intention. Therefore, designing self service technology to be fun will be the key to its success. This study focused on the touch screen self service technology in fast food restaurant. Although it has its limits due to the fact that it is hard to generalize the results to any other self service technology, the conceptual framework of this study can be applied to future research of any other service site.

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Weight loss effects of Bariatric Surgery after nutrition education in extremely obese patients (고도비만환자에서 베리아트릭 수술 (Bariatric Surgery) 후 영양교육이 체중감량에 미치는 효과)

  • Jeong, Eun-Ha;Lee, Hong-Chan;Yim, Jung-Eun
    • Journal of Nutrition and Health
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    • v.48 no.1
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    • pp.30-45
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    • 2015
  • Purpose: This study was planned to determine the characteristics of extremely obese patients during Bariatric surgery and to evaluate how the difference in the number of postsurgical personal nutritional educations they received affected the weight loss. Methods: This is a retrospective study on the basis of the medical records of extremely obese patients for 15 months after receiving gastric banding. A total of 60 people were selected as the study subjects and they were divided into the Less Educated Group and the More Educated Group according to the average number of personal nutritional educations they received. We investigated both groups to determine the general characteristic, health related lifestyle habits, obesity related complications and symptoms in possession, and eating habits before their surgery, the body composition measurement result, obesity determination indices at 1, 3, 6, 9, 12, and 15 months before and after their surgery, and the biochemical parameters at 6 months before and after their surgery. Results: Body fat and weight showed rapid reduction until 6 months after the surgery, but thereafter reduced slowly depending on the result of body composition measurement. Regarding body fat and weight, the More Educated Group, who received nutrition education more often, showed significantly lower levels than the Less Educated Group at 15 months after surgery. Regarding BMI and degree of obesity, the More Educated Group showed significantly lower levels than the Less Educated Group at 15 months after surgery. Here, we were assured that BMI is reversely proportional to the number of personal nutritional educations at 15 months, which is more outstanding after surgery than before surgery. Conclusion: Long-term nutritional education is a key factor for the extremely obese patient in maintaining the effects of Bariatric surgery on weight and body fat reduction onwards. In the next stage, considering the characteristics of the study subjects, adoption of individual nutrition education is recommended for postsurgical prospective arbitration of obesity in order to monitor blood pressure, obesity related complications, symptoms in possession, and how eating habits and health related life habits change, and to judge the actual effect of the nutritional education method at the same time.

Qualitative Research on Korean Baby-Boomer Generation Middle-Aged Women's Attitude Toward Their Lives - Based on Middle-Class Seoul Residents - (한국의 베이비부머세대 중년여성이 삶에서 추구하는 가치에 대한 질적연구 - 서울 거주 중산층을 중심으로 -)

  • Lee, Ji Hyun;Kim, Sun Woo
    • Asia Marketing Journal
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    • v.14 no.2
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    • pp.127-156
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    • 2012
  • A lot of interest in the baby-boomer generation, those who were born after World War II, has emerged since their retirement has been accelerated. The retirement of baby-boomers has caused many health, public welfare, social policy and family relationship problems. However, their increased purchasing power has made them more attractive consumers than any other generation, and they have become a fascinating niche market in the depressed economy. This research selected middle-class women of the baby-boomer generation who have had powerful effects on society and have emerged as an attractive niche market, and attempted to understand their lives intensively. Based on research activities, the purpose of this research is to identify baby-boomer generation middle-aged women's life values. Qualitative research methodology was used to achieve research objectives, and this research aimed to suggest marketing implications to connected industries based on the research results. The research objectives are as follows. 1. understanding the lives of baby-boomer middle-class women who have powerful effects on socio-economic phenomena 2. identifying the life values of baby-boomer middle-class women 3. generating marketing implications based on an understanding of baby-boomer middle-class women's lives and life values This research conducted FGIs(focus group interviews), one of the qualitative research methodologies, to figure out baby-boomer middle-class women's life values intensively and selected 10 women living in Seoul for data collection. The qualitative data of collected FGIs were analyzed with spiral data analysis methodology proposed by Creswell(2007). The most effective factors to influence these middle-class women's lives powerfully were 'time' and 'independence'. Their consciousness of the importance of using time affects their life pattern generally, and their independence also impacts greatly on the way they exploit time and on their diverse relationships. They maximized their self-realization and showed long-term partnership with their surrounding circumstances because of those effective factors. Baby-boomer middle-class women's self-realization was divided into two areas. One was their outside activities and another was perfect management of their physical appearance and home interior. Like the results of this research, their need for social entrance will be reinforced more strongly since their internal and external activities aim for the achievement of self-realization. In addition, this research suggests that baby-boomer middle-class women's activities are connected with their management of their physical appearance and home interior decorations, and that such management is caused not only by a simple interest in fashion and beauty but also a profound desire for self-realization. On account of their consciousness, which is different from other generations, Korean baby-boomer middle-class women are able to maintain positive partnerships with their surrounding circumstances; however, they also show ambivalent emotions to retain effective partnerships. To overcome those stressful situations, they make greater efforts to keep up their health and youth, and also engage in diverse activities to maintain their mental health. Finally, they generate positive attitudes toward their economic situation and extra time to develop self-realization and pursue happy, youthful and healthy lives. Based on those results, this study suggests the following implications. First, industries targeting the baby-boomer generation should develop innovative products and services which help the baby-boomer generation maximize their efficiency of time since time is one of the most important factors powerfully impacting the baby-boomer generation. They will engage in various activities to fill up their extra time and consume helpful products and services. Second, such industries should supply the baby-boomer generation with opportunities which propose new ways of self-realization since this generation shows a great desire for self-realization because of their self-efficacy. With customized strategies of satisfying their needs, the baby-boomer generation would discover opportunities to utilize their abilities, relationships and aesthetic senses, and industries would develop a niche market. Third, market segmentations which target the baby-boomer generation's desire to maintain their physical appearance and home interior should be executed since such activities are the main strategies to develop this generation's self-realization. The baby-boomer generation's desire to study those areas would be expanded, and those education systems should produce innovative products and services targeting the baby-boomer generation. This implication also offers to government officials new policies related with the baby-boomer generation. This exploratory study utilized qualitative research methodology to understand baby-boomer middle-class women's lives, and proposed propositions and limitations for further researches. As for the limitations, first, it is hard to generalize the research results so that they may apply to all areas and economic classes of the baby-boomer generation since this research selected only 10 women living in Seoul for the data collection process. To overcome this limitation, extended data collections of subjects from diverse regions and economic classes should be designed. Second, quantitative research should be conducted to supplement the findings with validities. Third, this research focused on only general ideas of the baby-boomer generation's lives since the range of this study was focused on their overall lives. Therefore, intensive research related to specific areas of their lives should be conducted.

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Analysis of Greenhouse Thermal Environment by Model Simulation (시뮬레이션 모형에 의한 온실의 열환경 분석)

  • 서원명;윤용철
    • Journal of Bio-Environment Control
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    • v.5 no.2
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    • pp.215-235
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    • 1996
  • The thermal analysis by mathematical model simulation makes it possible to reasonably predict heating and/or cooling requirements of certain greenhouses located under various geographical and climatic environment. It is another advantages of model simulation technique to be able to make it possible to select appropriate heating system, to set up energy utilization strategy, to schedule seasonal crop pattern, as well as to determine new greenhouse ranges. In this study, the control pattern for greenhouse microclimate is categorized as cooling and heating. Dynamic model was adopted to simulate heating requirements and/or energy conservation effectiveness such as energy saving by night-time thermal curtain, estimation of Heating Degree-Hours(HDH), long time prediction of greenhouse thermal behavior, etc. On the other hand, the cooling effects of ventilation, shading, and pad ||||&|||| fan system were partly analyzed by static model. By the experimental work with small size model greenhouse of 1.2m$\times$2.4m, it was found that cooling the greenhouse by spraying cold water directly on greenhouse cover surface or by recirculating cold water through heat exchangers would be effective in greenhouse summer cooling. The mathematical model developed for greenhouse model simulation is highly applicable because it can reflects various climatic factors like temperature, humidity, beam and diffuse solar radiation, wind velocity, etc. This model was closely verified by various weather data obtained through long period greenhouse experiment. Most of the materials relating with greenhouse heating or cooling components were obtained from model greenhouse simulated mathematically by using typical year(1987) data of Jinju Gyeongnam. But some of the materials relating with greenhouse cooling was obtained by performing model experiments which include analyzing cooling effect of water sprayed directly on greenhouse roof surface. The results are summarized as follows : 1. The heating requirements of model greenhouse were highly related with the minimum temperature set for given greenhouse. The setting temperature at night-time is much more influential on heating energy requirement than that at day-time. Therefore It is highly recommended that night- time setting temperature should be carefully determined and controlled. 2. The HDH data obtained by conventional method were estimated on the basis of considerably long term average weather temperature together with the standard base temperature(usually 18.3$^{\circ}C$). This kind of data can merely be used as a relative comparison criteria about heating load, but is not applicable in the calculation of greenhouse heating requirements because of the limited consideration of climatic factors and inappropriate base temperature. By comparing the HDM data with the results of simulation, it is found that the heating system design by HDH data will probably overshoot the actual heating requirement. 3. The energy saving effect of night-time thermal curtain as well as estimated heating requirement is found to be sensitively related with weather condition: Thermal curtain adopted for simulation showed high effectiveness in energy saving which amounts to more than 50% of annual heating requirement. 4. The ventilation performances doting warm seasons are mainly influenced by air exchange rate even though there are some variations depending on greenhouse structural difference, weather and cropping conditions. For air exchanges above 1 volume per minute, the reduction rate of temperature rise on both types of considered greenhouse becomes modest with the additional increase of ventilation capacity. Therefore the desirable ventilation capacity is assumed to be 1 air change per minute, which is the recommended ventilation rate in common greenhouse. 5. In glass covered greenhouse with full production, under clear weather of 50% RH, and continuous 1 air change per minute, the temperature drop in 50% shaded greenhouse and pad & fan systemed greenhouse is 2.6$^{\circ}C$ and.6.1$^{\circ}C$ respectively. The temperature in control greenhouse under continuous air change at this time was 36.6$^{\circ}C$ which was 5.3$^{\circ}C$ above ambient temperature. As a result the greenhouse temperature can be maintained 3$^{\circ}C$ below ambient temperature. But when RH is 80%, it was impossible to drop greenhouse temperature below ambient temperature because possible temperature reduction by pad ||||&|||| fan system at this time is not more than 2.4$^{\circ}C$. 6. During 3 months of hot summer season if the greenhouse is assumed to be cooled only when greenhouse temperature rise above 27$^{\circ}C$, the relationship between RH of ambient air and greenhouse temperature drop($\Delta$T) was formulated as follows : $\Delta$T= -0.077RH+7.7 7. Time dependent cooling effects performed by operation of each or combination of ventilation, 50% shading, pad & fan of 80% efficiency, were continuously predicted for one typical summer day long. When the greenhouse was cooled only by 1 air change per minute, greenhouse air temperature was 5$^{\circ}C$ above outdoor temperature. Either method alone can not drop greenhouse air temperature below outdoor temperature even under the fully cropped situations. But when both systems were operated together, greenhouse air temperature can be controlled to about 2.0-2.3$^{\circ}C$ below ambient temperature. 8. When the cool water of 6.5-8.5$^{\circ}C$ was sprayed on greenhouse roof surface with the water flow rate of 1.3 liter/min per unit greenhouse floor area, greenhouse air temperature could be dropped down to 16.5-18.$0^{\circ}C$, whlch is about 1$0^{\circ}C$ below the ambient temperature of 26.5-28.$0^{\circ}C$ at that time. The most important thing in cooling greenhouse air effectively with water spray may be obtaining plenty of cool water source like ground water itself or cold water produced by heat-pump. Future work is focused on not only analyzing the feasibility of heat pump operation but also finding the relationships between greenhouse air temperature(T$_{g}$ ), spraying water temperature(T$_{w}$ ), water flow rate(Q), and ambient temperature(T$_{o}$).

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