• Title/Summary/Keyword: 요인들

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Predicting Suitable Restoration Areas for Warm-Temperate Evergreen Broad-Leaved Forests of the Islands of Jeollanamdo (전라남도 섬 지역의 난온대 상록활엽수림 복원을 위한 적합지 예측)

  • Sung, Chan Yong;Kang, Hyun-Mi;Park, Seok-Gon
    • Korean Journal of Environment and Ecology
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    • v.35 no.5
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    • pp.558-568
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    • 2021
  • Poor supervision and tourism activities have resulted in forest degradation in islands in Korea. Since the southern coastal region of the Korean peninsula was originally dominated by warm-temperate evergreen broad-leaved forests, it is desirable to restore forests in this region to their original vegetation. In this study, we identified suitable areas to be restored as evergreen broad-leaved forests by analyzing the environmental factors of existing evergreen broad-leaved forests in the islands of Jeollanam-do. We classified forest lands in the study area into six vegetation types from Sentinel-2 satellite images using a deep learning algorithm and analyzed the tolerance ranges of existing evergreen broad-leaved forests by measuring the locational, topographic, and climatic attributes of the classified vegetation types. Results showed that evergreen broad-leaved forests were distributed more in areas with a high altitudes and steep slope, where human intervention was relatively low. The human intervention has led to a higher distribution of evergreen broad-leaved forests in areas with lower annual average temperature, which was an unexpected but understandable result because an area with higher altitude has a lower temperature. Of the environmental factors, latitude and average temperature in the coldest month (January) were relatively less contaminated by the effects of human intervention, thus enabling the identification of suitable restoration areas of the evergreen broad-leaved forests. The tolerance range analysis of evergreen broad-leaved forests showed that they mainly grew in areas south of the latitude of 34.7° and a monthly average temperature of 1.7℃ or higher in the coldest month. Therefore, we predicted the areas meeting these criteria to be suitable for restoring evergreen broad-leaved forests. The suitable areas cover 614.5 km2, which occupies 59.0% of the total forest lands on the islands of Jeollanamdo, and 73% of actual forests that exclude agricultural and other non-restorable forest lands. The findings of this study can help forest managers prepare a restoration plan and budget for island forests.

A Study on the Reasonable Measurement Point of Root Collar Diameter of Landscape Trees in Korea (한국 조경수목 근원직경 측정의 합리적 위치 설정에 대한 연구)

  • Han, Yong-Hee;Kim, Hwa-Jeong;Kim, Do-Gyun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.5
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    • pp.59-70
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    • 2021
  • This study was to investigate the measurement point of root collar diameter of landscape trees in Korea. It may contribute to avoiding disputes caused by the difference in measurement criteria of root collar diameter of landscape trees between tree growers and constructors. The difference between landscape trees' root collar diameter measurement point was 3.59cm from 6cm underground to the surface and 1.35cm from 0cm to 6cm above ground. The source root collar diameter measurement point difference was larger in the basement than in the ground. The standard deviation of the root collar diameter of the landscape tree was 0.64 from 6cm underground to the surface, and the difference in standard deviation from 0cm to 6cm above ground was 0.16. The difference by measurement point of the root collar diameter was larger in the basement than in the ground. It has been proposed to set the reasonable measurement point of the landscaping tree root collar diameter at the inflection point where the standard deviation of the tree trunk diameter is the smallest in line with the size change of the standard for each root collar diameter measurement point. By tree species, Cornus officinalis Siebold & Zucc. 18cm above the ground, Chionanthus retusus Lindl. & Paxton. 12cm above the ground, Zelkova serrata (Thunb.) Makino. 12cm above the ground, Celtis sinensis Pers. 12cm above the ground, Styrax japonicus Siebold & Zucc. 10 cm above the ground, Cornus officinalis Siebold & Zucc. 10cm above the ground, Acer palmatum Thunb. ex Murray. 6cm above the ground, Ilex rotunda Thunb. 6cm above the ground, Quercus myrsmaefolia Blume. 4cm above the ground, Lagerstroemia indica L. 2cm above the ground The above heights were shown as reasonable measurement points. The difference by landscape tree root collar diameter measurement site showed that the standard deviation was small throughout the tree species, and the reasonable average measurement point with a stable slope of the deviation was 12cm or more on average. It can be said that the reasonable measurement point of the root collar diameter of a landscape tree is set at an average of 12cm above the ground. However, recognizing 30cm, which is a familiar ruler(尺) in traditional practices, is quick, It was recommended to measure at the height of 30cm from the surface for a reasonable measurement point of the root collar diameter of a landscape tree, for the uniformity of measurement standards.

Effects of Physical Factors on Urban Surfaces on Air Quality - Chang Chun, China as an Example - (도시표면의 물리적 요소가 대기질에 미치는 영향 - 중국 창춘을 사례로 -)

  • Jin, Quanping;Kim, Tae Kyung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.5
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    • pp.1-11
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    • 2021
  • The purpose of this study is to find out the main factors affecting air quality in urban physical space factors, and provide clues for environmental improvement. Nine monitoring stations in China's industrial city, Changchun, collected AQI concentration data from January 1, 2018 to December 31, 2019. This paper analyzes the types and distribution characteristics of urban physical facilities within a radius of 300m with the detection station as the center. The monitoring station is divided into three groups, and the difference in floating dust concentration among the three groups in different seasons is analyzed. The results show that AQI concentration is the highest in spring and winter, followed by summer, and the lowest in autumn. The place with the highest concentrations of AQI in spring are F (93.00), D (91.10), I (89.20), in summer are D (69.05), A (67.89), B (84.44), in autumn are I (62.80), G (60.84), D (53.27), D (53.27), in winter are I (95.82), H (95.60), f (94.04). Through SPSS analysis, it shows that the air index in a space with a diameter of 600 meters is related to forest land, grassland, bare land, water space, tree height, building area (average value), and building volume (average value). According to the statistical analysis results of spring and winter with the most serious pollution, forest land area (43,637m2, 15.44%) and water surface area (18,736m2, 6.63%) accounted for the majority, and group 1 (A, B, C) with the least average building area (448m2, 0.17%) and average building volume (10,201m2) had the lowest pollution concentration. On the contrary, group 2 (D, E, F) had the highest AQI concentration, with less or no woodland (1,917m2, 0.68%) and water surface area (0m2, 0%), and the highest average building area (1,056m2, 0.37%) and average building volume (17,470m3). It is confirmed that the characteristics of the area with the highest AQI concentration are that the more the site ratio of tree height above 12m, the smaller the site ratio of bare land, and the lower the pollution degree. On the contrary, the larger the area of bare land, the higher the pollution degree. By analyzing the characteristics of nine monitoring stations in Changchun, it can be seen that the air quality brought by the physical characteristics of urban space is closely related to the above factors.

An Exploratory Study on the Industry/Market Characteristics of the 'Hyper-Growing Companies' and the Firm Strategies: A Focus on Firms with more than Annual Revenue of 100 Million dollars from 'Inc. the 5,000 Fastest-Growing Private Companies in America' (초고성장 기업의 산업/시장 특성과 전략 선택에 대한 탐색적 연구: 'Inc. the 5,000 Fastest-Growing Private Companies in America' 기업 중 연간 매출액 1억 달러 이상 기업을 중심으로)

  • Lee, Young-Dall;Oh, Soyoung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.2
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    • pp.51-78
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    • 2021
  • Followed by 'start-up', the theme of 'scale-up' has been considered as an important agenda in both corporate and policy spheres. In particular, although it is a term commonly used in industry and policy fields, even a conceptual definition has not been achieved from the academic perspective. "Corporate Growth" in the academic aspect and "Business Growth" in the practical management field have different understandings (Achtenhagen et al., 2010). Previous research on corporate growth has not departed from Penrose(1959)'s "Firm as a bundle of resources" and "the role of managers". Based on the theory and background of economics, existing research has mainly examined factors that contribute to firms' growth and their growth patterns. Comparatively, we lack knowledge on the firms' growth with a focus on 'annual revenue growth rate'. In the early stage of the firms, they tend to exhibit a high growth rate as it started with a lower level of annual revenue. However, when the firms reach annual revenue of more than 100 billion KRW, a threshold to be classified as a 'middle-standing enterprise' by Korean standards, they are unlikely to reach a high level of revenue growth rate. In our study, we used our sample of 333 companies (6.7% out of 5,000 'fastest-growing' companies) which reached 15% of the compound annual growth rate in the last three years with more than USD 100 million. It shows that sustaining 'high-growth' above a certain firm size is difficult. The study focuses on firms with annual revenue of more than $100 billion (approximately 120 billion KRW) from the 'Inc. 2020 fast-growing companies 5,000' list. The companies have been categorized into 1) Fast-growing companies (revenue CAGR 15%~40% between 2016 and 2019), 2) Hyper-growing companies (40%~99.9%), and 3) Super-growing (100% or more) with in-depth analysis of each group's characteristics. Also, the relationship between the revenue growth rate, individual company's strategy choice (market orientation, generic strategy, growth strategy, pioneer strategy), industry/market environment, and firm age is investigated with a quantitative approach. Through conducting the study, it aims to provide a reference to the 'Hyper-Growing Model' that combines the paths and factors of growth strategies. For policymakers, our study intends to provide a reference to which factors or environmental variables should be considered for 'optimal effective combinations' to promote firms' growth.

Yield Characteristics and Related Agronomic Traits Affected by the Transplanting Date in Early Maturing Varieties of Rice in the Central Plain Area of Korea (중부 평야지에서 조생종 벼의 이앙시기에 따른 수량 특성 변화와 작물학적 요인 분석)

  • Yang, Woonho;Park, Jeong-Hwa;Choi, Jong-Seo;Kang, Shingu;Kim, Sukjin
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.3
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    • pp.165-175
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    • 2019
  • In response to elevated temperature, a shift in the rice planting period was proposed as a promising option in temperate regions. To understand the yield response of early maturing rice to different transplanting dates and to analyze the related agronomic traits in the central plain area, we performed a two-year study using different transplanting dates and six varieties in Suwon, Korea. The maximum head rice weight was achieved in the treatments transplanted between June 14 and 29, depending upon the varieties. The optimal mean temperature during the 40 days from heading stage for attaining the maximum head rice weight was $21.8^{\circ}C$ on the average of six varieties. The index of head rice weight was positively correlated with the indices of both the milled rice weight and head rice percentage, the latter showing a higher coefficient of determination. The highest milled rice weight was commonly achieved from the treatment transplanted on June 29, where the head rice weight was also the highest. The index of milled rice weight was significantly correlated with the indices of grain filling percentage and number of spikelets per area, but not correlated with the index of 1000-brown rice weight. The transplanting date with the highest milled rice yield produced the largest number of spikelets per area, greatest biomass at the heading and harvesting stages, and highest level of harvest index. We suggest that the optimal transplanting date for early maturing rice varieties in the central plain area is from June 14 to 29. High head rice yield in this study was attributed to increased spikelets owing to the increased biomass production at the heading stage, enhanced grain filling due to the high biomass production and harvest index at maturity, and improved head rice percentage.

Needs and Related Factors for Return-to-Work Support in Cancer Survivors (암 경험자의 직장복귀지원에 대한 요구도 및 관련 요인)

  • Lee, Sungwon;Lee, Kwang-Min;Oh, Gyu-Han;Yeom, Chan-Woo;Jung, Sanghyup;Hahm, Bong-Jin
    • Korean Journal of Psychosomatic Medicine
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    • v.28 no.2
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    • pp.126-134
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    • 2020
  • Objectives : The purpose of this study was to investigate the needs for return-to-work support of cancer survivors and related factors in patients with cancer and their caregivers. Methods : 182 patients and 114 caregivers were recruited. Distress Thermometer and Problem List and scale ranging 0~10 measuring the degree of needs for return-to-work support were utilized. The needs for return-to-work support between the patient group and caregiver group (patient's needs evaluated by the caregiver) were compared, and related factors were investigated using logistic regression analysis. Results : 34.6% and 28.1% of patients and caregivers reported return-to-work support of cancer survivors is "very necessary". The degree of needs was 6.60±3.365 points in the patient group and 6.17±3.454 points in the caregiver group, with no significant difference (p=0.282). The needs for return-to-work support evaluated by patients was high when they underwent surgery (OR=2.592, p=0.007), has fertility problems (OR=6.137, p=0.025), has appearance problems (OR=2.081, p=0.041), or has fatigue (OR=2.330, p=0.020). The needs for return-to-work support of patients evaluated by caregivers was high when patients treated with breast cancer (vs respiratory cancer, OR=13.038, p=0.022 ; vs leukemia/lymphoma, OR=4.517, p=0.025 ; vs other cancer, OR=13.102, p=0.019), has work/school problems (OR=4.578, p=0.005), or has depression (OR=3.213, p=0.022). Conclusions : The degree of needs for return-to-work support of cancer survivors was high, and factors related to the needs were different between the two groups. This suggests that return-to-work support of cancer survivors is required, and clinical characteristics, the distress of patients, and differences between patients and their caregivers should be considered in establishing a support plan.

Effects of Gadolinium Contrast agent on Bone Mineral Density Measurement using Dual Energy X-ray Absorptiometry (가돌리늄조영제가 이중에너지 X-선 흡수법을 이용한 골밀도검사에 미치는 영향)

  • Lee, Keun-Ohk;Lee, Min-Su
    • Journal of the Korean Society of Radiology
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    • v.15 no.1
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    • pp.63-70
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    • 2021
  • Radiographic contrast agents are used for diagnostic purposes and are one of the factors affecting measured values in bone density tests. They are absorbed into tissues and have an effect of increasing the measured values of bone density, so they are avoided as much as possible before performing a bone density test. MRI contrast agents, which have different physical properties and mechanisms of action than radiographic contrast agents, are based on gadolinium, a metal element. They have radiopacity characteristics, so MRI are generally performed prior to examination using radiation. The purpose of this study was to investigate the effects of MRI contrast agents on bone mineral density examination using dual energy X-ray absorption. Two types of gadolinium based MRI contrast agents were injected into an acrylic water tank for each volume, and the humanoid spine phantom was inserted and the BMD and T-score from (L1-L4) were analyzed by scanning a total of 30 times, 5 times for each injection type. The average value of the measured total (L1-L4) bone density for each of the two contrast agents was 0.952±0.052, 0.957±0.050, and 0.956±0.05g/㎠, respectively, for the Gadoterate Meglumine component 0mL, 7.5mL and 15mL, when the gadobutrol components were 0mL, 5mL, and 10mL, there was no statistically significant difference at all sites at 0.953±0.001, 0.954±0.001, and 0.945±0.001g/㎠, respectively(p>0.05). The average value of total T-score was -0.46±0.05, -0.4±0, -0.42±0.04 when the Gadoterate Meglumine component was 0mL, 7.5mL and 15mL, respectively. When the Gadobutrol ingredients were 0mL, 5mL and 10mL, there was no statistically significant difference in all areas, with -0.46±0.05, -0.46±0.05, and 0.5±0.00, respectively. In this experiment, the MRI contrast agent was found to have no effect on bone density tests, using the dual-energy X-ray absorption method. There is a limitation in that physical conditions such as kidney and health conditions etc. were not taken into consideration, so further clinical research is expected to be conducted in the future.

Evaluation of dietary behavior and investigation of the affecting factors among preschoolers in Busan and Gyeongnam area using nutrition quotient for preschoolers (NQ-P) (미취학 아동 대상 영양지수 (nutrition quotient for preschoolers, NQ-P)를 이용한 부산·경남지역 미취학 아동의 식행동 평가 및 영향요인 규명)

  • Kim, Soo-Youn;Cha, Sung-Mi
    • Journal of Nutrition and Health
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    • v.53 no.6
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    • pp.596-612
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    • 2020
  • Purpose: This study was conducted to evaluate the dietary behaviors of preschool children using the nutrition quotient for preschoolers (NQ-P) and investigate factors that influence NQ-P in preschool children. Methods: Subjects were 214 parents with children aged 3-5 years residing in Busan and Gyeongnam, Korea. The survey was conducted from March to April, 2019 using a questionnaire that included demographic characteristics, the NQ-P questions, and health consciousness. All data was statistically analyzed by the SPSS program (Ver 25.0) and the statistical differences in variables were evaluated by the chi-square test, Fisher's exact test, t-test, one-way ANOVA, and Tukey's multiple comparison test. Results: The mean score of NQ-P of the total subjects was 58.28, which was within the medium-low grade. The mean score of 'balance' was 60.08, 'moderation' was 47.64, and 'environment' was 67.83. The analysis of related-factors influencing NQ-P scores showed that there was a significant difference according to the frequency of dining out. The scores of the NQ-P (p < 0.05), moderation (p < 0.001), and environment (p < 0.05) were significantly higher in the 1-2 times per week group compare to 3-4 times and 5-6 times per week group. The scores of NQ-P (p < 0.01), environment (p < 0.01) were significantly higher in the high group of parents' health consciousness compared to the those with low health consciousness. Conclusion: According to the results of the evaluation by NQ-P, the dietary behaviors of preschool children residing in Busan and Gyeongnam need to be improved and monitored. For improving their eating behavior and nutritional health status, preschool children and their parents need proper nutrition education programs.

A History of Termite Control and Improvements to Prevent Termites in Wooden Architectural Heritage (국내외 흰개미 방제 기술의 발달 과정과 목조건축문화재의 흰개미 피해 저감을 위한 방안)

  • LEE, Sangbin;IM, Ikgyun;KIM, Sihyun
    • Korean Journal of Heritage: History & Science
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    • v.54 no.2
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    • pp.194-215
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    • 2021
  • Termites are important decomposers in the ecosystem. They are also economically significant structural pests. In this study, we reviewed the developments of termite control and recent research on termite management to provide information on the prevention and control of termites. In Korea, most of the damage to wooden historical buildings is caused by subterranean termites. Reticulitermes speratus kyushuensis is the main species, which is widely found throughout the country. In the early 1900s, inorganic insecticides, such as arsenic dust, were used for termite control. After the synthesis of chlorinated hydrocarbon pesticide in the 1940s, it was widely utilized and demonstrated high termite control efficacy. However, chlorinated hydrocarbon insecticides were later banned, disappearing from markets after reports emerged concerning environmental contamination and toxicity to humans. Therefore, the termite control industry sought a new termiticide; hence many pesticides were utilized for termite control. Organophosphate (1960s), carbamate (1970s), pyrethroid, and insect growth inhibitor (1980s) were newly synthesized and adopted. In the 1990s, the first commercial baits using chitin synthesis inhibitors (CSI) were developed, providing a means to eliminate an entire colony of subterranean termites around a structure. Many studies have been carried out on soil termiticides (liquid termiticides) and CSI baits to increase their efficacy, and different baits such as aboveground bait stations, fluid bait, and high-durability bait were also developed in the 2000s. In addition, the paradigm of termite control has shifted from localized treatments using soil termiticides to area-wide pest management using CSI baits to create termite-free zones and protect buildings over time. Termite infestations in wooden historical buildings in Korea have been reported since 1980, and considerable attention was drawn in the 1990s when several UNESCO world heritages such as the Jongmyo Shrine and the Janggyeong Panjeon Depositories of Haeinsa Temple were infested by subterranean termites. Since then, a survey of termite infestation in wooden architectural heritage has been conducted, and the National Research Institute of Cultural Heritage and Heritage Care Program regularly monitors those properties. Finally, we suggest termite management using primarily CSI baits, selective application of various soil treatments applied to the object, foundation soil treatment, research and development of durable termite baits, application of area-wide programs for wooden-building complexes, application of integrated termite management (ITM), and regular education for owners and managers to prevent and reduce termite damage.

Evaluation of Patient Radiation Doses Using DAP Meter in Interventional Radiology Procedures (인터벤션 시술 시 면적선량계를 이용한 환자 방사선 선량 평가)

  • Kang, Byung-Sam;Yoon, Yong-Su
    • Journal of radiological science and technology
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    • v.40 no.1
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    • pp.27-34
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    • 2017
  • The author investigated interventional radiology patient doses in several other countries, assessed accuracy of DAP meters embedded in intervention equipments in domestic country, conducted measurement of patient doses for 13 major interventional procedures with use of Dose Area Product(DAP) meters from 23 hospitals in Korea, and referred to 8,415 cases of domestic data related to interventional procedures by radiation exposure after evaluation the actual effectives of dose reduction variables through phantom test. Finally, dose reference level for major interventional procedures was suggested. In this study, guidelines for patient doses were $237.7Gy{\cdot}cm^2$ in TACE, $17.3Gy{\cdot}cm^2$ in AVF, $114.1Gy{\cdot}cm^2$ in LE PTA & STENT, $188.5Gy{\cdot}cm^2$ in TFCA, $383.5Gy{\cdot}cm^2$ in Aneurysm Coil, $64.6Gy{\cdot}cm^2$ in PTBD, $64.6Gy{\cdot}cm^2$ in Biliary Stent, $22.4Gy{\cdot}cm^2$ in PCN, $4.3Gy{\cdot}cm^2$ in Hickman, $2.8Gy{\cdot}cm^2$ in Chemo-port, $4.4Gy{\cdot}cm^2$ in Perm-Cather, $17.1Gy{\cdot}cm^2$ in PCD, and $357.9Gy{\cdot}cm^2$ in Vis, EMB. Dose referenece level acquired in this study is considered to be able to use as minimal guidelines for reducing patient dose in the interventional radiology procedures. For the changes and advances of materials and development of equipments and procedures in the interventional radiology procedures, further studies and monitorings are needed on dose reference level Korean DAP dose conversion factor for the domestic procedures.