• Title/Summary/Keyword: uncertainty management

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An Empirical Study on the Determinate Factors and Performance of Corporate R&D Outsourcing (기업의 연구개발 아웃소싱의 결정요인과 성과에 관한 실증적 연구)

  • Hwang, Yong-Sik
    • 한국벤처창업학회:학술대회논문집
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    • 2009.10a
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    • pp.111-138
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    • 2009
  • This research focuses on what factors determine firm's decisions on R&D outsourcing and how R&D outsourcing affect R&D performance. In recent years many firms outsource R&D activities instead of internalizing it. Thus, further investigation is necessary to find out this recent trend. Based on several theoretical background the study developed three determining factors of R&D outsourcing which are transactional level, firm level, and risk level. Transactional level composes of independent variables such as R&D cost saving, asset specificity and uncertainty which mainly comes from Transaction Cost Economics theory. Firm level composes of openness to technology from outer source, R&D capability, and outsourcing experience. Risk level composes of technological risk, cost-related risk and managerial risk. The result shows that R&D outsourcing is significantly related to cost saving aspect, low asset specific firms, firms without solid technological background, firms which are open to external technology, firms with other types of outsourcing experience, and firms which take technological risks. However, proposed relationship between degree of R&D outsourcing and R&D performance found out to be insignificant. This research is contribute to the field of outsourcing study since it will give guidance to managers who need to make strategic decisions on R&D outsourcing activities.

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The Nutritional Status by Stress on Freshmen of University (대학 신입생의 스트레스 민감 여부에 따른 영양상태)

  • Lee, Young-Hee;Rhie, Seung-Gyo;Won, Hyang-Rye
    • The Korean Journal of Community Living Science
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    • v.17 no.4
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    • pp.81-95
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    • 2006
  • This study was made to find out how stress affect on nutrition status of the college freshmen who were experiencing physical growth and development as well as drastic emotional change. 400 male and female freshmen in 4 year colleges were surveyed respectively through the health check-up procedure for college entrance in February, In order to find out the stress in each group frustration, deprivation, lack of self efficacy, type A behavior and anxiety response were surveyed through 10 questions with total 40 points by assigning 4 points for each question. Diet Status was expressed by DDS (Dietary Diversity Score by 5 food groups) and DVS(Dietary Variety Score). 24-hrs recall method was used to find out the quantity of daily nutrient of EAR(estimated adquacy ratio) by KDRIs(Korean Dietary Recommended Intakes). Nutrition level was analyzed by Can-Pro for professionals (Korea Nutrition Association). And for the quality intake, percentage was calculated and MAR(Mean Adequacy Ratio) were produced. Highest point was obtained in the stress of anxiety with the total 40 score of 30.20, and the scores were 29.79, 28.67, and 28.39 for deprivation, type A behavior and frustration respectively. There was no difference of blood components in accordance with stress type. Stress type was divided into less sensitive group and highly sensitive one and the relationship with the blood nutrient status was observed. The difference of blood component and blood pressure in sensitive and highly sensitive groups was observed in deprivation and anxiety. The index of blood pressure(p<0.05), hemoglobin(p<0.01), HDL-cholesterol(p<0.05), and Fe(p<0.05) was high in the deprivation of sensitive group. Blood pressure and hemoglobin was high in type A of sensitive group(p<0.05). And the contents of blood triglyceride was high in the anxiety of sensitive group(p<0.001) The result of nutrition intake analysis according to stress type showed that there was low intake for energy, riboflavin, and niacin. When the degree of deprivation was high there was a lack of riboflavin intake and there was no significant difference of nutrition intake in lack of self efficacy, type A behavior and anxiety response. Thus, it is necessary for colleges to educate the students to maintain mental stability through various programs and activities after catching a kind and extent of the stress college students we meeting with like the confusion of value system, open heterosexual relationship, and the employment difficulties linked with political uncertainty and economic recession.

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Establishment of the Korean Tolerable Daily Intake of Bisphenol A Based on Risk Assessments by an Expert Committee

  • Choi, Chan-Woong;Jeong, Ji-Yoon;Hwang, Myung-Sil;Jung, Ki-Kyung;Lee, Kwang-Ho;Lee, Hyo-Min
    • Toxicological Research
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    • v.26 no.4
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    • pp.285-291
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    • 2010
  • Recently, reproductive and neurobehavioral effects of bisphenol A (BPA) have been documented, and thus a review was requested for BPA management direction by the government. Therefore, this study was performed to establish a Korean tolerable daily intake (TDI) for BPA. An expert committee, consisting of specialists in fields such as toxicology, medicine, pharmacology, and statistics, was asked to evaluate BPA health based guidance values (HbGVs). Although many toxicological studies were reviewed to select a point of departure (POD) for TDI, rat and mouse reproductive studies by Tyl et al. (2002, 2006), which were performed according to GLP standards and OECD guidelines, were selected. This POD was the lowest value determined from the most sensitive toxicological test. The POD, a NOAEL of 5 mg/kg bw/day, was selected based on its systemic toxicity as critical effects. An uncertainty factor of 100 including interspecies and intraspecies differences was applied to calculate the TDI. According to the evaluation results, a TDI of BPA for Korean was suggested at 0.05 mg/kg bw/day. In addition, the BPA exposure level based on food consumption by the Korean population was estimated as 1.509 ${\mu}g/kg$ bw/day, and the HI was evaluated at 0.03 when the TDI of 0.05 mg/kg bw/day was applied. This HI value of 0.03 indicated that hazardous effects would not be expected from BPA oral exposures. Although highly uncertain, further studies on low dose neurobehavioral effects of BPA should be performed. In addition, it is recommended that the 'as low as reasonably achievable' (ALARA) principle be applied for BPA exposure from food packaging materials in newborn infants and children.

Water Quality Model Development for Loading Estimates from Paddy Field (논에서의 오염부하 예측을 위한 범용모형 개발)

  • Jeon, Ji-Hong;Hwang, Ha-Sun;Yoon, Kwang-Sik;Yoon, Chun-Gyeong
    • Korean Journal of Ecology and Environment
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    • v.36 no.3 s.104
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    • pp.344-355
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    • 2003
  • Water quality model applicable paddy field was developed using field experiment during 1999 ${\sim}$ 2002. This model involves inputs from fertilization and sediment release as dirac delta function and continuous source function, respectively, and can simulate various processes such as ponded depth, surface drainage, total nitrogen concentration and total phosphorus concentration in a daily basis. The model was calibrated using data collected from field experiments which was irrigated with ground water and validated from field experiments which was irrigated with surface water. The nutrient concentration of surface water depended on the fertilization and dirac delta function can efficiently explain the valiance of nutrient concentration of surface water by fertilizer. As a result of calibration and validation, this model demonstrates good agreement. The model fit efficiencies ($R^2$) of ponded depth, surface concentration of TN and TP were 0.93,0.98 and 0.95, respectively for calibration, and those of TN and TP were 0.99 and 0.70, respectively for validation. We can apply lake and reservoir model to analysis paddy field considered with shallow ponded system, but it will need so many parameters and have much uncertainty. Fortunately, paddy field have a series of cultural practices yearly basis, such as irrigation-fertilization-forced drain-harvest with a similar time , so simple model may explain the mechanism for paddy field. Water quality model for paddy field developed in this study is simply, needs little parameters, but appeared high applicability to evaluate paddy filed drainage. We recommend this model to estimate nutrient loading from paddy field and establish best management practice.

The Relationship between Perceived Oral Health Status and Entrance Exam Stress Levels in High School Students (고등학생의 입시스트레스 수준과 주관적 구강건강상태의 관련성)

  • Kim, Se-Ra;Han, Su-Jin
    • Journal of dental hygiene science
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    • v.15 no.4
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    • pp.509-517
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    • 2015
  • This study attempted to identify the entrance exam stress levels in high school students and analyze the relationship this entrance exam stress and perceived oral health status. Self-administered survey was conducted in total 304 students attending in academic high schools in Bucheon. For analysis, SPSS was used to perform t-test and one-way ANOVA. As a result of the study, the entrance exam stress level of academic high school students was 2.71. The level of sub-factors were that tension for exam/poor result was highest by 3.08 and the next were future uncertainty (2.81), parents pressure (2.56), and insufficient free time (2.52). The group with high entrance exam stress showed significantly high perceived degrees of temporomandibular disorder, oral mucosal disease and xerostama. Among sub-factors of stress, the group with high tension for exam/poor result stress had significantly high perceived degrees of dental caries, teporomandibular disorder, oral mucosal disease and xerostama. Because perception on oral health issues increased with high entrance exam stress in high school students, it is necessary to seek some ways to decrease oral health problems even though entrance exam stress is intensified. To do so, it is inferred that it will be very important to promote oral health education to develop ability of high school students to practice correct oral management method.

Comparison of farmer happiness and rural life satisfaction through the survey of major agricultural products panel

  • Park, Kye Won;Choe, Seung Hui;Jo, Seung Yeon;Kim, In Jae;Min, Byung Ik
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.307-307
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    • 2017
  • There is a growing need to understand how local, farm household, and elementary units are responding to changes in agricultural conditions due to increased internal and external agrarian conditions and increased uncertainty in agricultural management due to increasing FTA and climate change. Therefore, we analyze dynamics of changes through more detailed and precise gathering of information related to agricultural products and DB, and by analyzing the satisfaction level of the first year panel survey by constructing a producer panel for utilization in agricultural research and policy. A total of 500 farmers in the producer panel who mainly grow rice, garlic, onion, strawberry, apple were collected through questionnaires. The actual analysis used data from a total of 393 farm households, including 82 farms of rice, 51 farms of apple, 100 farms of garlic, 88 farms of onion and 72 farmhouses of strawberry. The distribution by age was similar to the distribution of rural ages in Korea, with 2.8% under 30s, 17.6% in 40s, 32.4% in 50s, 37.5% in 60s and 9.7% in 70s. Panel happiness and rural life satisfaction were examined using the 7 - point Likert scale and the analysis method was one - way ANOVA. The results showed that the happiness of garlic and strawberry cultivator was significantly higher than that of rice and onion cultivator. However, the satisfaction of rural life did not show any difference among the cultivars. As a result of difference verification about Agricultural Outlook and Crop-specific Outlook after 5 years, there was no difference between the crops in terms of prospects for Korean agriculture after five years, but a survey of industrial prospects for crops after five years showed that the rice growers have a significantly negative outlook compared to garlic, onion and strawberry growers, and garlic and onion growers have a more positive outlook than rice and apple growers As a result of verifying whether there is a difference in ages between the agricultural prospects and the industrial prospects by crops after 5 years, there was no difference between the ages of prospects for Korean agriculture after 5 years, However, in the survey on industrial prospects by crops after 5 years, 40s were more positive than 60s.

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The Reason to Select Complementary and Alternative Therapy for Terminally Ill Cancer Patients (말기암환자가 보완대체요법을 선택한 이유)

  • Kim, Kyeong-Uoon;Park, Jean-No;Lee, Soo-Han
    • Journal of Hospice and Palliative Care
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    • v.14 no.1
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    • pp.34-41
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    • 2011
  • Purpose: The purpose of this study was to analyze the reason to select complementary and alternative therapy for terminally ill cancer patients. Methods: The data were collected from 21 terminal cancer patients and families through the in-depth interview. Data analysis were performed by the Colaizzi's phenomenological method (1976). Results: The reason to select complementary and alternative therapy for terminal cancer patients and families was then categorized with 4 elements; Awareness of limitations in contemporary medical treatments, Belief in effectiveness of the CAM, Satisfaction with emotional needs of family members, and Disbelief due to negative attitudes of physicians. The result indicated the following 9 themes expectation for a complete cure, uncertainty in hospital treatments, complementary method for management of side effect of chemotherapy, alleviation of symptoms and life-sustaining, fear for side effects of cancer treatments, belief in earned information, referrals by other, responsibility of family, and dissatisfaction with negatine attitudes of physicians. Conclusion: Physicians should provide a sufficient explanation and try to effectively communicate with clients about hospice and palliative service and the CAM. We strongly realized that concerns about patients' best care and satisfactions with family's needs should be understood.

Soil Resilience and Threat Factors Related to Agricultural Environment (농업환경 분야에서의 토양 리질리언스와 그 위협 요인)

  • Kim, Min-Suk;Min, Hyun-Gi;Hyun, Seung-Hun;Kim, Jeong-Gyu
    • Ecology and Resilient Infrastructure
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    • v.7 no.1
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    • pp.26-42
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    • 2020
  • Soils are the basis for plant rooting and ecosystem creation, the site of life for humankind, and require much time for their creation, so there will be no disagreement about the importance and necessity of soil conservation and management. Soil resilience is the ability of soils to maintain their original structure and function (resistance and recovery) from various kinds of disturbances, and is an indispensable field of study that prepares for a future with high uncertainty and unpredictability. Therefore, this study summarizes the concept and necessity of soil resilience, which is not yet widely known in Korea, and the contents of previous studies were reviewed. This study was carried out with the aim of contributing to lowering the threshold for entry into resilience research for domestic and foreign researchers who are new to soil resilience. In the first part of this study, we introduced resilience and soil resilience, and in the second part, we summarized the main causes of stress or disturbance that have been studied by many soil resilience researches. This makes it easy to find the references authors need. It is virtually impossible to find the same soil environment because there is no same area on the earth with all the same rock, climate, human activity, and culture, suggesting that each soil has its own uniqueness. Therefore, the researcher who wants to utilize the results of this study should take into consideration the specificity of the soil and the region to which the soil resilience is introduced, and modify it if necessary. In addition, efforts should be made to strengthen the network of soil resilience researchers to create a basis for sharing and actively utilizing the research results.

An Improved Movable 3 photomultiplier (3PM)-γ Coincidence Counter Using Logical Sum of Double Coincidences in β-Channel for Activity Standardization

  • Hwang, Han Yull;Lee, Jong Man
    • Journal of Radiation Protection and Research
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    • v.45 no.2
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    • pp.76-80
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    • 2020
  • Background: To improve the measurement accuracy of liquid-scintillation counting for activity standardization, it is necessary to significantly reduce the background caused by thermal noise or after-pulses. We have therefore improved a movable 3 photomultiplier (3PM)-γ coincidence-counting method using the logical sum of three double coincidences for β events. Materials and Methods: We designed a new data-acquisition system in which β events are obtained by counting the logical sum of three double coincidences. The change in β-detection efficiency can be derived by moving three photomultiplier tubes sequentially from the liquid-scintillation vial. The validity of the method was investigated by activity measurement of 134Cs calibrated at the Korea Research Institute of Standards and Science (KRISS) with 4π(PC)β-γ(NaI(Tl)) coincidence counting using a proportional counter (PC) for the β detector. Results and Discussion: Measurements were taken over 14 counting intervals for each liquidscintillation sample by displacing three photomultiplier tubes up to 45 mm from the sample. The dead time in each β- and γ-counting channel was adjusted to be a non-extending type of 20 ㎲. The background ranged about 1.2-3.3 s-1, such that the contributions of thermal noise or after-pulses were negligible. As the β-detection unit was moved away from the sample, the β-detection efficiencies varied between 0.54 and 0.81. The result obtained by the method at the reference date was 396.3 ± 1.7 kBq/g. This is consistent with the KRISS-certified value of 396.0 ± 2.0 kBq/g within the uncertainty range. Conclusion: The movable 3PM-γ method developed in the present work not only succeeded in reducing background counts to negligible levels but enabled β-detection efficiency to be varied by a geometrical method to apply the efficiency extrapolation method. Compared with our earlier work shown in the study of Hwang et al. [2], the measurement accuracy has much improved. Consequently, the method developed in this study is an improved method suitable for activity standardization of β-γ emitters.

An Assessment and Review of IUCN Red List for Vascular Plants in Korean Peninsula (한반도 관속식물 IUCN 적색목록 평가와 문제점)

  • Chang, Chin-Sung;Kim, Hye Won;Kim, Hui
    • Journal of Korean Society of Forest Science
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    • v.106 no.2
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    • pp.111-120
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    • 2017
  • The best source of information on the conservation status of species at a global scale is the IUCN Red List of Threatened Species. Until now, 236 vascular plants from Korean peninsula have been evaluated using the IUCN red list categories and criteria. It indicated that five taxa were considered as critically endangered, 20 as endangered and nine as vulnerable species as a threatened status. On the other hand, the rest (189 taxa) were assessed as a least concern, which did not qualify for threatened species categories. Korea Ministry of Environment published a revised version of 57 species list by re-classifying endangered species with idiosyncratic qualitative criteria for two levels (I and II) followed by status reviews in 2011. However, two thirds species proposed by Ministry of Environment do not qualify as threatened. The major difficulties found in applying IUCN Red List criteria at the global scale was a lack of knowledge on the status of species at broader geographic scales and the perceived difficulty the causes. The lack of consistency between two lists constrains the prioritization of species-based conservation work at the national level. Due to a lack of centralized monitoring data for most species, this status is largely qualitatively and so it carries a high level of uncertainty. This is reflected in the high number of species with an unknown population trend. The current list of endangered species of flora and fauna by the Ministry of Environment should be recognized as the national list (local and population extinction), which is different from the IUCN Red list due to the different geographical contexts. Also, it is necessary to improve the quality of evaluation and conservation management system rather than presenting massive number of endangered species list.