• Title/Summary/Keyword: 유효 효율

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The Growth Performances and Soil Properties of Planted Zelkova serrata Trees according to Fertilization in Harvested Pinus rigida Plantation over 6 Years after Planting (조림지 시비 처리에 따른 리기다소나무 벌채지 내 식재 6년 후 느티나무 조림지 토양 및 조림목 생장 특성)

  • Yang, A-Ram;Cho, Min Seok
    • Journal of Korean Society of Forest Science
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    • v.108 no.1
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    • pp.29-39
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    • 2019
  • The objective of this study was to suggest a suitable amount of fertilizer using the changes in growth performances and soil properties for improving survival and quality of Zelkova serrata trees in a harvested Pinus rigida plantation. One-year-old containerized seedlings of Z. serrata were planted with the density of 3000 seedlings $ha^{-1}$ in end of March 2011 at Gwangneung experimental forest, Pocheon. Solid compound fertilizer (N:P:K=3:4:1) were applied yearly in three amounts (control: no fertilization, F1: $180kg\;ha^{-1}$, and F2: $360kg\;ha^{-1}$) every May from 2011 to 2013. We analyzed soil properties before (2011) and after (2012 and 2017) fertilization. And we measured the root collar diameter and height of Z. serrata trees from 2011 to 2016, and then calculated H/D ratio and stem volume. Soil properties at Z. serrata plantation did not show difference according to fertilization level in every investigation year. As time passed after planting, however, concentrations of total nitrogen and available phosphorus were increased from decreased. The growth of root collar diameter, height and stem volume of Z. serrata trees at F2 plot were significantly higher those at the other plots after only 2 years of fertilization. Because Z. serrata tree demand to more nutrient during the early growing period. The survival rate of Z. serrata trees at control plot was significantly lower than that at the other plots. This might be due to Z. serrata trees at control plot had not the upper hand from competition with vegetation at the early in planting. However, the growth of height and stem volume of Z. serrata trees between F1 and F2 plots did not show difference over 6 years after planting. Consequently, we could suggest that Z. serrata trees need to F1 fertilization level for considering improving survival and quality of Z. serrata trees and economical efficiency of plantation managements after harvesting P. rigida plantation.

Effects of Fermented Mixed Organic Fertilizer Utilizing By-Products on Soil Properties and the Yield of Organic Lettuce (부산물 활용 발효 유기질비료 처리에 따른 유기 상추 토양 특성 및 수량에 미치는 영향)

  • An, Nan-Hee;Lee, Sang-min;Hwang, Hyun-Young;Park, Sang-Gu;Lee, Cho-Rong
    • Journal of the Korea Organic Resources Recycling Association
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    • v.29 no.3
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    • pp.41-48
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    • 2021
  • This study aimed to develop an alternative organic fertilizer to castor oil cake-based fertilizers. To assess the nutrient effect of the developed fermented mixed organic fertilizers, the yield of lettuce and soil characteristics after growth were analyzed and compared to those of a trial using a mixed expeller cake fertilizer. Two fermented mixed organic fertilizers, FA and FB, each containing 5.0% nitrogen, 2.6% phosphate, and 1.4% potassium, were produced by mixing different ratios of rice bran, dried distillers grains, sesame oil meal, and fish meal. This study was conducted with six trials: untreated, mixed expeller cake fertilizer, and the fermented mixed organic fertilizers FA and FB. Based on the amount of nitrogen fertilization (70 kg ha-1) on the lettuce, the fermented mixed organic fertilizers FA and FB were applied at 100% and 150%, respectively, and the mixed oil cake was applied at 100%. As the amount of treatment increased, there was no significant difference except the number of leaves in FA treatment. The yields from the FA100 and FB100 treatments were 38.2 and 40.8 Mg ha-1, respectively, which was not significantly different from that of the mixed expeller cake fertilizer treatment at 38.3 Mg ha-1. In addition, the nitrogen uptake and utilization efficiency of the lettuce were not significantly different between mixed expeller cake fertilizer and fermented mixed organic fertilizer treatments. Analysis of the chemical properties of the soil after the trial showed that he mixed expeller cake fertilizer treatment showed the lowest pH. There were no significant differences in electrical conductivity, content of soil organic matter, available phosphate, and exchangeable cation among the fertilizer treatments. However, the bacterial and actinomyces density was higher in the soil from the fertilizer trials than in the non-fertilizer trials. These results indicated that the two tested fermented mixed organic fertilizers had nourishing effects and soil characteristics that were similar to those of the mixed expeller cake fertilizer. Thus, farmers can use these fermented mixed organic fertilizers as alternatives to castor oil cakes for the cultivation of organic lettuce.

Growth and Useful Component of Angelica gigas Nakai under High Temperature Stress (고온 스트레스에 따른 참당귀의 생육 및 유용성분 특성)

  • Jeong, Dae Hui;Kim, Ki Yoon;Park, Sung Hyuk;Jung, Chung Ryul;Jeon, Kwon Seok;Park, Hong Woo
    • Korean Journal of Plant Resources
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    • v.34 no.4
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    • pp.287-296
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    • 2021
  • Recently, the pace of global climate change has tremendously increased, causing extreme damage to crop production. Here, we aimed to examine the growth characteristics and useful components of Angelica gigas under extreme heat stress, providing fundamental data for its efficient cultivation. Plants were exposed to various experimental temperatures (28℃, 34℃, and 40℃), and their growth characteristics and content of useful components were analyzed. At the experimental site, the ambient and soil temperature were 19.38℃ and 21.34℃, ambient and soil humidity were 81.3 % and 0.18 m3/m3, solar radiation was 162.05 W/m2. Moreover, the soil was sandy-clay-loam (pH 6.65), with 2.66% organic matter, 868.52 mg/kg soil available phosphate, and 0.14% nitrogen. Values of most growth characteristics, including the survival rate (85%), plant height (38.66cm), and fresh and dry weight (41.3 g and 14.24 g), were the highest at 28℃. Although the highest content of useful components was observed at 34℃ (3.24%), there were no significant differences across temperatures. Growth characteristics varied across temperatures due to detrimental effects of heat stress, such as accelerated tissue aging, reduced photosynthesis, and delay of growth. Similar content of useful components across temperatures may be due to poor accumulation of anabolic products caused by impaired growth at extremely high temperatures.

Business Incubator Manager's Competency Characteristics Affect Organizational Commitment and Work Performance : Focused on the Manager's Self-Efficacy (창업보육센터 매니저의 역량 특성이 조직몰입과 업무성과에 미치는 영향 : 매니저의 자기효능감을 중심으로)

  • Park, Sang-Ho;Kang, Shin-Cheol
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.1
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    • pp.71-85
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    • 2021
  • Representative domestic start-up support organizations include the Business Incubator(BI), Korea Institute of Startup & Entrepreneurship Development(KISED), Techno Park(TP), and Center of Creative Economy Innovation(CCEI), and there are about 260 Business incubator nationwide. The Business incubator is operated by universities, research institutes, and private foundations or associations. The organization consists of the center director and the incubating professionals (hereinafter referred to as "manager"), etc., and performs tasks such as center operation management and incubation support services for tenant companies. Until now, research on the operation of Business Incubator has been mainly focused on the performance of tenant companies. Studies on whether the manager's competency characteristics directly or indirectly affect the performance of the tenant companies through psychological mediators such as self-efficacy and organizational commitment were very scarce. The purpose of this study is to explore various factors influencing organizational commitment and job performance by the competence characteristics of Business incubator managers, and to explain the causal relationship among those factors. In particular, the difference in perception was investigated by a manager's survey that influences organizational commitment and work performance at the Business incubator. Through this, we intend to present practical implications for the role of managers in the operation of Business incubators. This study is an exploratory study, and the subject of the study was a survey of about 600 managers working at Business incubator nationwide, of which 116 responses were analyzed. Data analysis included descriptive statistics, exploratory factor analysis, and reliability. Structural equation model analysis was performed for hypothesis tests. As a result of the analysis, it was found that the cognitive characteristics of the Business incubator manager, communication, and situational response as the behavioral characteristics had a positive effect on the manager's self-efficacy, and the behavioral characteristics had a greater effect on the self-efficacy. It was also found that the manager's cognitive and behavioral characteristics, and self-efficacy had a positive effect on organizational commitment and work performance. In particular, a manager's self-efficacy has a positive effect on organizational commitment and work performance. This result showed that the manager's competency characteristics increase the manager's self-efficacy as a mediating factor rather than directly affecting organizational commitment and work performance. This study explains that the manager's competency characteristics are transferred to organizational commitment and work performance. The results of the study are expected to reflect the job standard of the National Competency Standards (NCS) and basic vocational competency to the job competency of managers, and it also provides a guideline for the effective business incubator operation in terms of human resource management. In practice, it is expected that the results of the study can reflect the vocational basic skills of the Business Incubator manager's job competency in the National Competency Standards(NCS) section, and suggest directions for the operation of the Business Incubator and the manager's education and training.

Thermal Behavior and Leaf Temperature in a High Pressure Sodium Lamp Supplemented Greenhouse (고압나트륨등 보광 온실의 열적 거동 및 엽온 분석)

  • Seungri Yoon;Jin Hyun Kim;Minju Shin;Dongpil Kim;Ji Wong Bang;Ho Jeong Jeong;Tae In Ahn
    • Journal of Bio-Environment Control
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    • v.32 no.1
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    • pp.48-56
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    • 2023
  • High-pressure sodium (HPS) lamps have been widely used as a useful supplemental light source to emit sufficient photosynthetically active radiation and provide a radiant heat, which contribute the heat requirement in greenhouses. The objective of this study to analyze the thermal characteristics of HPS lamp and thermal behavior in supplemented greenhouse, and evaluate the performance of a horizontal leaf temperature of sweet pepper plants using computational fluid dynamics (CFD) simulation. We simulated horizontal leaf temperature on upper canopy according to three growth stage scenarios, which represented 1.0, 1.6, and 2.2 plant height, respectively. We also measured vertical leaf and air temperature accompanied by heat generation of HPS lamps. There was large leaf to air temperature differential due to non-uniformity in temperature. In our numerical calculation, thermal energy of HPS lamps contributed of 50.1% the total heat requirement on Dec. 2022. The CFD model was validated by comparing measured and simulated data at the same operating condition. Mean absolute error and root mean square error were below 0.5, which means the CFD simulation values were highly accurate. Our result about vertical leaf and air temperature can be used in decision making for efficient thermal energy management and crop growth.

Estimation of the Korean Yield Curve via Bayesian Variable Selection (베이지안 변수선택을 이용한 한국 수익률곡선 추정)

  • Koo, Byungsoo
    • Economic Analysis
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    • v.26 no.1
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    • pp.84-132
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    • 2020
  • A central bank infers market expectations of future yields based on yield curves. The central bank needs to precisely understand the changes in market expectations of future yields in order to have a more effective monetary policy. This need explains why a range of models have attempted to produce yield curves and market expectations that are as accurate as possible. Alongside the development of bond markets, the interconnectedness between them and macroeconomic factors has deepened, and this has rendered understanding of what macroeconomic variables affect yield curves even more important. However, the existence of various theories about determinants of yields inevitably means that previous studies have applied different macroeconomics variables when estimating yield curves. This indicates model uncertainties and naturally poses a question: Which model better estimates yield curves? Put differently, which variables should be applied to better estimate yield curves? This study employs the Dynamic Nelson-Siegel Model and takes the Bayesian approach to variable selection in order to ensure precision in estimating yield curves and market expectations of future yields. Bayesian variable selection may be an effective estimation method because it is expected to alleviate problems arising from a priori selection of the key variables comprising a model, and because it is a comprehensive approach that efficiently reflects model uncertainties in estimations. A comparison of Bayesian variable selection with the models of previous studies finds that the question of which macroeconomic variables are applied to a model has considerable impact on market expectations of future yields. This shows that model uncertainties exert great influence on the resultant estimates, and that it is reasonable to reflect model uncertainties in the estimation. Those implications are underscored by the superior forecasting performance of Bayesian variable selection models over those models used in previous studies. Therefore, the use of a Bayesian variable selection model is advisable in estimating yield curves and market expectations of yield curves with greater exactitude in consideration of the impact of model uncertainties on the estimation.

A Study on the Effects of Export Insurance on the Exports of SMEs and Conglomerates (수출보험이 국내 중소기업 및 대기업의 수출에 미치는 영향에 관한 연구)

  • Lee, Dong-Joo
    • Korea Trade Review
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    • v.42 no.2
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    • pp.145-174
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    • 2017
  • Recently, due to the worsening global economic recession, Korea which is a small, export-oriented economy has decreased exports and the domestic economy also continues to stagnate. Therefore, for continued growth of our economy through export growth, we need to analyze the validity of export support system such as export insurance and prepare ways to expand exports. This study is to investigate the effects of Export Insurance on the exports of SMEs as well as LEs. For this purpose, this study conducted Time Series Analysis using data such as export, export insurance acquisition, export price index, exchange rate, and coincident composite index(CCI). First, as a result of the Granger Causality Test, the exports of LEs has found to have a causal relationship with the CCI, and CCI is to have a causal relationship with the short-term export insurance record. Second, the results of VAR analysis show that the export insurance acquisition result and the export price index have a positive effect on the exports of LEs, while the short - term export insurance has a negative effect on the exports of LEs. Third, as a result of variance decomposition, the export of LEs has much more influenced for mid to long term by the short-term export insurance acquisition compared to SMEs. Fourth, short-term export insurance has a positive effect on exports of SMEs. In order to activate short-term export insurance against SMEs, it is necessary to expand support for SMEs by local governments. This study aims to suggest policy implications for establishing effective export insurance policy by analyzing the effects of export insurance on the export of SMEs as well as LEs. It is necessary to carry out a time series analysis on the export results according to the insurance acquisition results by industry to measure the export support effect of export insurance more precisely.

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Archival Science and Constitutional Point of View (헌법적 관점의 기록학)

  • Lee, Youngnam
    • The Korean Journal of Archival Studies
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    • no.79
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    • pp.121-168
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    • 2024
  • Record & archives management is at the heart of archival science. We must be faithful to record & archives management. However, isn't there a paradox that arises the more faithful we are to record & archives management? The paradox is that 'being a responsible manager and efficiently managing records' is rather reduces the interest in the social existence of humans who create and use such records. Why do humans produce and use records? It may be because human beings have been living with the concept of records. The concept is 'the same as the design of thoughts'. There is no need to doubt this direction because as record & archives management develops, more valuable records are preserved more systematically, and they are been served with wider scope and appropriateness. However, if we observe this situation from a human point of view rather than record & archives management, we find that humans appearing in record & archives management are limited to the object of using records. If humans are perceived differently based on the hypothesis of reviewing from the ground up, we can encounter a unique context about the relationship between humans and records or between records and humans. If it reaches the norm that human beings have dignity that cannot be transferred to anyone, have the right to pursue happiness, and must live by enjoying freedom, equality, and social basic rights, in short, if human beings are recognized from a constitutional point of view, we can newly recognize the social role and direction of records. The constitution and international human rights norms document basic human rights as the final norm and clarify that it is the duty of the state to guarantee and practice them. The social role of records from a constitutional point of view is the practice of records that proliferate basic human rights. The practice of archiving, which multiplies basic human rights, may also be a civic consciousness required of experts, but on the other hand, it can be a professional way for archival studies. If record management is a two-lane round trip, it can be said that the interaction between record management and record practice, which multiplies basic human rights, is a pioneering four-lane round trip. This article examines the practice of archiving, which has been developed in and out of record & archives management, by clearly grasping the constitutional perspective from the perspective of archival studies, and examines the social role of archival studies in this context. The social role of archival studies is to provide new linguistic rules for archiving.

The Effect of Empathy Value of Chinese Female University Students on Affection with Sustainable Fashion Products on Affection and Purchase Intention (중국 여대생의 지속가능한 패션제품에 대한 공감가치가 호감도와 구매의사에 미치는 영향)

  • Yi-Fei Wu;Young-Sook Lee
    • Journal of Internet of Things and Convergence
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    • v.10 no.3
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    • pp.35-48
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    • 2024
  • This study analyzed the value empathy of environmentally sustainable fashion products, encompassing environmental, economic, and social values, drawing from existing literature. We sought to verify the relationship between empathic value and the likability and purchase intention towards these products. To validate these relationships, we formulated research hypotheses and conducted an online survey targeting female college students residing in Guangzhou, Guangdong Province, China, who have experience purchasing environmentally sustainable fashion products. The survey was conducted from August 10th to August 20th, 2023, with a total distribution of 352 questionnaires. Among the collected responses, 313 valid responses were utilized for data analysis. The collected survey data underwent frequency analysis, exploratory factor analysis, reliability and validity analysis, correlation analysis, and multiple regression analysis using SPSS 26.0 software. The analysis yielded the following results. First, the empathy value of environmentally sustainable fashion products was classified into environmental protection values, economic values, and social values. Second, the economic and social values of environmentally sustainable fashion products were found to have a positive effect on favorability. Third, it was found that the environmental protection value and social value of environmentally sustainable fashion products had a positive effect on purchase intention. Fourth, it was found that Chinese female college students' favorability toward environmentally sustainable fashion products had a positive effect on their purchase intention. Based on these results, it is judged that companies need to emphasize the characteristics of products such as environmental protective value, economic value, and social value in order to promote consumers' purchase of environmentally sustainable fashion products. The purpose of this study is to help develop marketing strategies for environmentally sustainable fashion products by providing basic data, development ideas, and methods useful for environmentally sustainable fashion-related industries and companies by analyzing the relationship between empathy value, favorability, and purchase intention.

Evaluation on Growth Characteristics of Red Pepper (Capsicum annuum L.) and Soil Chemical Properties by Continuous Application of Food Waste Compost with Manure (음식물류폐기물 혼합 가축분 퇴비 연용에 따른 고추(Capsicum annuum L.) 생육 및 토양 화학적 특성 평가)

  • Jin-Ju Yun;Young-Jae Jeong;Seong-Heon Kim;Sang-Ho Jeon;Ahn-Sung Roh;Soon-Ik Kwon;Yu-Na Lee;Jae-Hong Shim
    • Journal of the Korea Organic Resources Recycling Association
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    • v.32 no.3
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    • pp.31-41
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    • 2024
  • Food waste compost with high salt content produced by aerobic digestion, but concerns about application of cropland. To address this issue, food waste is being composted by mixing it with livestock manure, which has a lower salt content. Therefore, this study aimed to evaluate the growth characteristics of red pepper and soil chemical properties for continuous application with different amounts of food waste compost with manure (FWC). Treatments were consisted of no fertilizer (NF), inorganic fertilizer (N-N-P2O5-K2O, 19.0-11.2-14.9 kg 10a-1), and inorganic fertilizer + food waste compost with manure (NPKFWC). FWC treatment was applied at three treatment rates based on soil organic matter content: 900 kg 10a-1, 1,800 kg 10a-1, and 2,700 kg 10a-1 ( referred to a s FWC 1, 2, 3 , respectively). As a r esult of the red pepper yield was about 1.8 times higher in NPKFWC 1 and NPKFWC 2 than that in the NF, but decreased in the NPKFWC 3, 300% of the recommended FWC application rate. Yield decreased in all FWC treatments with continuous application for three year and also decreased about 40% from 3,265 kg 10a-1 in the first year to 1,948 kg 10a-1 in the third year. For the soil chemical properties, the content of soil organic matter, available P2O5, and exchangeable cations increased in the FWC treatments, and were higher than the NF. Exchangeable sodium in all treatments was increased slightly compared to the soil before used, and no significant salinization was observed in the FWC. This study confirmed that excessive use of FWC not only reduced nutrient use efficiency, but also decreased the red pepper yield. Therefore, it is concluded that optimum usage of FWC is effective for agroecological impacts.