• Title/Summary/Keyword: Expanding ratio

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Study on the Evaluation CO2 Emission-Absorption of Concrete in the View of Carbonation (콘크리트의 탄산화 관점에서 CO2 배출량-흡수량 평가에 관한 연구)

  • Lee, Sang-Hyun;Lee, Sung-Bok;Lee, Han-Seung
    • Journal of the Korea Concrete Institute
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    • v.21 no.1
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    • pp.85-92
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    • 2009
  • A concrete is considered unfriendly-environmental material because it uses cement which emits much $CO_2$ during producing process. However, a concrete absorbs $CO_2$ through carbonation process during service life. In this paper how much concrete absorbs $CO_2$ through carbonation was calculated using 1) concentration of carbonatable substances in concrete, 2) carbonated volume of concrete, 3) molecular weight of $CO_2$ based on references and the method was proposed. $CO_2$ emission from producing $1m^3$ concrete was calculated based on $CO_2$ emission datum of materials used in concrete. From using these methods that calculate $CO_2$ emission and absorption of concrete, assessment of $CO_2$ emission-absorption against a real apartment was conducted by subtracting absorption $CO_2$ according to service life from $CO_2$ emission in the process of making concrete. As a result, a ratio of absorption over emission of $CO_2$ through concrete carbonation according to service life 40, 60, 80 years was assessed about 3.65, 4.47, 5.18%. An objective of this study is to propose how to calculate emission - absorption of $CO_2$ from producing and using concrete. Although the result value, emission - absorption of $CO_2$, is 5.18% very low when the service life of an apartment is 80years, the value can be improved by reducing emission from using blended cement such as blast furnace slag or increasing replacement ratio of cement and increasing carbonated volume of concrete from expanding service life of a building. This study may be useful when $CO_2$ emission - absorption of concrete is evaluated in the further study.

Game Theoretic Optimization of Investment Portfolio Considering the Performance of Information Security Countermeasure (정보보호 대책의 성능을 고려한 투자 포트폴리오의 게임 이론적 최적화)

  • Lee, Sang-Hoon;Kim, Tae-Sung
    • Journal of Intelligence and Information Systems
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    • v.26 no.3
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    • pp.37-50
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    • 2020
  • Information security has become an important issue in the world. Various information and communication technologies, such as the Internet of Things, big data, cloud, and artificial intelligence, are developing, and the need for information security is increasing. Although the necessity of information security is expanding according to the development of information and communication technology, interest in information security investment is insufficient. In general, measuring the effect of information security investment is difficult, so appropriate investment is not being practice, and organizations are decreasing their information security investment. In addition, since the types and specification of information security measures are diverse, it is difficult to compare and evaluate the information security countermeasures objectively, and there is a lack of decision-making methods about information security investment. To develop the organization, policies and decisions related to information security are essential, and measuring the effect of information security investment is necessary. Therefore, this study proposes a method of constructing an investment portfolio for information security measures using game theory and derives an optimal defence probability. Using the two-person game model, the information security manager and the attacker are assumed to be the game players, and the information security countermeasures and information security threats are assumed as the strategy of the players, respectively. A zero-sum game that the sum of the players' payoffs is zero is assumed, and we derive a solution of a mixed strategy game in which a strategy is selected according to probability distribution among strategies. In the real world, there are various types of information security threats exist, so multiple information security measures should be considered to maintain the appropriate information security level of information systems. We assume that the defence ratio of the information security countermeasures is known, and we derive the optimal solution of the mixed strategy game using linear programming. The contributions of this study are as follows. First, we conduct analysis using real performance data of information security measures. Information security managers of organizations can use the methodology suggested in this study to make practical decisions when establishing investment portfolio for information security countermeasures. Second, the investment weight of information security countermeasures is derived. Since we derive the weight of each information security measure, not just whether or not information security measures have been invested, it is easy to construct an information security investment portfolio in a situation where investment decisions need to be made in consideration of a number of information security countermeasures. Finally, it is possible to find the optimal defence probability after constructing an investment portfolio of information security countermeasures. The information security managers of organizations can measure the specific investment effect by drawing out information security countermeasures that fit the organization's information security investment budget. Also, numerical examples are presented and computational results are analyzed. Based on the performance of various information security countermeasures: Firewall, IPS, and Antivirus, data related to information security measures are collected to construct a portfolio of information security countermeasures. The defence ratio of the information security countermeasures is created using a uniform distribution, and a coverage of performance is derived based on the report of each information security countermeasure. According to numerical examples that considered Firewall, IPS, and Antivirus as information security countermeasures, the investment weights of Firewall, IPS, and Antivirus are optimized to 60.74%, 39.26%, and 0%, respectively. The result shows that the defence probability of the organization is maximized to 83.87%. When the methodology and examples of this study are used in practice, information security managers can consider various types of information security measures, and the appropriate investment level of each measure can be reflected in the organization's budget.

Public Attitudes toward Development of National Program for Cancer Survivorship (암 생존자를 위한 국가 프로그램 개발에 대한 일반 국민들의 태도)

  • Bae, Yeon-Min;Kim, Young-Ae;Hong, Sung-Hoo;Koo, Ja-Hyun;Yun, Young-Ho
    • Journal of Hospice and Palliative Care
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    • v.14 no.4
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    • pp.218-226
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    • 2011
  • Purpose: This study aimed to explore the public attitude toward the development of national health program for cancer survivorship. Based on the results of this survey suggest the necessity of national health program for cancer survivorship. Methods: We surveyed 1,015 adults who were over 20 years of age from the sixteen cities and local districts of Korea. We conducted a telephone survey with a structured questionnaire on the post-treatment care at the nation and on the permission as the handicapped for cancer. Results: Fifty-six percent of respondents answered that post-treatment program at the national level is very necessary and twenty-seven percent replied that it is necessary. Respondents emphasized 'Expanding insurance coverage for post-treatment care' (29.8%) and 'Systematic education and rehabilitation programs after treatment' (25.6%). This study found that a lower educational level [adjusted odds ratio (aOR)=1.36; 95% confidence interval (CI)=1.04~1.77], earning under 300 per month [aOR=1.36; 95% CI=1.04~1.77], being married (60.2%) [aOR=1.79; 95% CI=1.34~2.37] and thought higher level of cancer treatment in Korea than the advanced (64.4%) [aOR=1.56; 95% CI=1.15~2.12] influenced the positive attitude toward a national health program. Sixty-eight percent of respondents answered 'Strongly agree' or 'agree' to permission for cancer survivors as the handicapped. People who have been married (72.4%) [aOR=1.89; 95% CI=1.41~2.53] and who have had a lower educational level [aOR=1.35; 95% CI=1.03~1.78] responded that they agree more to permission for cancer survivors as the handicapped. Conclusion: This study shows the positive public attitude of the public toward the national health program for the cancer survivors.

A Study on the Connectivity Modeling Considering the Habitat and Movement Characteristics of Wild Boars (Sus scrofa) (멧돼지(Sus scrofa) 서식지 및 이동 특성을 고려한 연결성 모델링 연구)

  • Lee, Hyun-Jung;Kim, Whee-Moon;Kim, Kyeong-Tae;Jeong, Seung-Gyu;Kim, Yu-Jin;Lee, Kyung Jin;Kim, Ho Gul;Park, Chan;Song, Won-Kyong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.25 no.4
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    • pp.33-47
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    • 2022
  • Wild boars(Sus scrofa) are expanding their range of behavior as their habitats change. Appearing in urban centers and private houses, it caused various social problems, including damage to crops. In order to prevent damage and effectively manage wild boars, there is a need for ecological research considering the characteristics and movement characteristics of wild boars. The purpose of this study is to analyze home range and identify land cover types in key areas through tracking wild boars, and to predict the movement connectivity of wild boars in consideration of previous studies and their preferred land use characteristics. In this study, from January to June 2021, four wild boars were captured and tracked in Jinju city, Gyeongsangnam-do, and the preferred land cover type of wild boars was identified based on the MCP 100%, KDE 95%, and KDE 50% results. As a result of the analysis of the home range for each individual, it was found that 100% of MCP was about 0.68km2, 2.77km2, 2.42km2, and 0.16km2, and the three individuals overlapped the home range, refraining from habitat movement and staying in the preferred area. The core areas were analyzed as about 0.55km2, 2.05km2, 0.82km2, and 0.14km2 with KDE 95%., and about 0.011km2, 0.033km2, 0.004km2, and 0.003km2 with KDE 50%. When the preferred land cover type of wild boar was confirmed based on the results of analysis of the total home range area and core area that combined all individuals, forests were 55.49% (MCP 100%), 54.00% (KDE 95%), 77.69% (KDE 50%), respectively, with the highest ratio, and the urbanization area, grassland, and agricultural area were relatively high. A connectivity scenario was constructed in which the ratio of the land cover type preferred by the analyzed wild boar was reflected as a weight for the resistance value of the connectivity analysis, and this was compared with the connectivity evaluation results analyzed based on previous studies and wild boar characteristics. When the current density values for the wild boar movement data were compared, the average value of the existing scenario was 2.76, the minimum 1.12, and the maximum 4.36, and the weighted scenario had an average value of 2.84, the minimum 0.96, and the maximum 4.65. It was confirmed that, on average, the probability of movement predictability was about 2.90% better even though the weighted scenario had movement restrictions due to large resistance values. It is expected that the identification of the movement route through the movement connectivity analysis of wild boars can be suggested as an alternative to prevent damage by predicting the point of appearance. In the future, when analyzing the connectivity of species including wild boar, it is judged that it will be effective to use movement data on actual species.

Effect of Mixture of Hymexazole and Metalaxyl on Growth and Low Temperature Injury in Rice Seedlings (Hymexazole과 Metalaxyl의 혼합제처리가 수도 유묘의 생육 및 저온장해에 미치는 영향)

  • 이병규;최원열
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.3
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    • pp.201-210
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    • 1990
  • This study was carried out to determine the effect of mixture of hymexazole and metalaxyl(Tachigarace) on the growth and reducing low temperature injury in rice seedlings. The amount of mixture of hymexazole and metalaxyl (Tachigarace) applied to reduce low temperature injury was 0, 9, 18 and 36mgr per pot (5${\times}$15${\times}$10cm) by soil incorperation befor sowing. Aging seedling was investigated on the growth responses by the application of 0.36gr mixture of hymexazole and metalaxyl (Tachigarace) per tray (30${\times}$60${\times}$3cm) after cutting of leaf at 35 day-old seedling. Rice seedlings treated with mixture of hymexazole and metalaxyl (Tachigarace) were better in the growth of top and roots, dry weight, erecting and rooting abilities than untreated seedlings. The effective amount of mixture of hymexazole and metalaxyl (Tachigarace) to increase erecting and rooting abilities was 18 mgr per pot. Under low temperature treatment, 12$^{\circ}C$, the leaf discoloration and dead leaf percent of rice seedlings were markedly decreased in the seedlings treated with mixture of hymexazole and metalaxyl (Tachigarace) as compared with untreated seedlings. The more amount of mixture of hymexazole and metalaxyl (Tachigarace) upto 36mgr per pot, the more effective on the low temperature injury in the seedling. The effect of mixture of hymexazole and metalaxyl (Tachigarace) to reduce low temperature damage in rice seedlings was mainly due to decreasing less physiological activities on the expanding leaf area and rooting, transpiration, stomatal diffusion and chlorophyll content of the leaves and oxygen consumption of the roots. Plant height, top dry weight and leaf area of aging seedlings were increased with mixture of hymexazole and metalaxyl (Tachigarace) treatment and leaf cutting as compared with untreated seedling and intact leaf, respectively. The ratio of missing hill of aging seedling was increased with increasing the period of growing seedling and was decreased due to leaf cutting, whereas the effect of mixture of hymexazole and metalaxyl (Tachigarace) application was not observed. Rooting ability of aging seedlings was decreased with lengthening of the period of raised seedling and was increased with mixture of hymexazole and metalaxyl (Tachigarace) treatment and leaf cutting.

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Promotional Strategies of Local Drugstores

  • Kim, Seung-Mi;Lee, Sang-Yoon;Kim, Pan-Jin;Kim, Nam-Myun;Youn, Myoung-Kil
    • The Journal of Industrial Distribution & Business
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    • v.1 no.1
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    • pp.5-12
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    • 2010
  • The retail business of drugstore was introduced to Korea for the first time 10 years ago. Since Olive Young introduced a retail store in the name of drugstore in 1999 for the first time in Korea, new distribution channel combining drugstore, cosmetic products and dairy products, etc has been made. At initial stage, the new distribution channel grew up slowly because of low specialty and economic stagnation. However, the three big distribution channels, that is to say, Olive Young (CJ), Watsons (GS) and W Store (Kolon Well Care), etc, were established to produce new distribution system following large-scaled discount stores as well as convenience stores. The purpose of the study is to investigate ways making Korean style drugstore be new retail business in addition to traditional markets, department stores, E-Mart and other general super markets and to examine problems preventing the drugstore from being promoted and to find out solutions. The speciality retailers that is called a category killer attacking department stores as well as marts is expanding market quickly. New consumption trend that gives priority to wellbeing is being expanded in accordance with high level of standards of living life: The drugstore is thought to be new alternative of distribution because it keeps special products. Young ladies who are main customers of drugstores respond to the trend sensitively to have more buying power that is thought to be promising. And, consumers' desire has become concrete and special. This is because consumers want not only convenient shopping but also special shopping system that is current trend. These days, so called Multi-shop and Total shop and other special shops have been recently opened. Special multi-shop has been concentrated on fashion product and miscellaneous goods so far: Health total wellbeing shop shall be popular in accordance with wellbeing trends. Drugstores can play an important role. Drugstores were opened for the first time ten years ago. In particular, Olive Young succeeded in going into the black after making efforts for a long time by many persons. Drugstores could succeed in the business owing to many persons in the past as well as customers who liked drugstores. However, drugstores once lost ways and recorded poor business results. The three drugstores, that is to say, Olive Young, Watsons making efforts to go into the black and W-Store pursuing traditional drugstore shall compete each other and make effort to satisfy customers' desire. In that way, the three drugstores can be assured of present business as well as future business. The consumers' demand trend has become special at sub-division so that drugstores that can satisfy the demand can succeed in the business. Large businesses may be more interested in the 4th generation retail business to produce good income and to have bright future. Drugstore business and market are likely to expand and develop owing to large business' participation in drugstore business. Drugstores expanded shop at Seoul and Gyeonggi-do until middle of 2000. Drugstore business at station sphere in Seoul and Gyeonggi-do that have high ratio of temporary population has low customer loyalty to have limitation on continuous growth. Since 2009, drugstores have opened new shops at local towns: From the year of 2010, drugstores need to establish multiple shop strategy by accelerating business speed and to allow customers to drop in the shop anywhere in the nation and to enter consumers' life deeply, so that they can strengthen business base definitely. Drugstores need to have price competitiveness to have multiple shop opening strategy and to satisfy consumers and to supply high quality services that is future subject to solve. And, Olive Young and Watsons that are Korean style drugstore need to keep system in order and to strengthen substance as Korean style drugstore and to expand marketing, so that they can get business outcome within 5 years that was done 10 years before and they become the 4th generation retail business. The study had difficulties at collecting material from the three drugstore because of poor cooperation. And, the author had great difficulty at collecting statistical material that was made in disorder. Further effort is needed considering such problems.

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In-House Subcontracting and Industrial Relations in Japanes Steel Industry (일본 철강산업의 사내하청과 노사관계)

  • Oh, Haksoo
    • Korean Journal of Labor Studies
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    • v.24 no.1
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    • pp.107-156
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    • 2018
  • This article examines the history of the in - house subcontracting and the stabilization of labor - management relations in the steel industry in Japan. The ratio of in-house subcontract workers among steel workers has increased steadily until the mid-2000s, and about 70% in case of the largest company. In-house subcontracting was used as a strategy of the company to increase the quantity flexibility of employment and to save labor costs. The in-house subcontracting company needed company-specialized skills, and the internal labor market was formed because the rate of full-time workers was high and the turnover rate was low. The in-house subcontractor introduced long-term business relationship with the steel factory by introducing the equipment and materials necessary for the performance of the work, and the factory implemented the productivity improvement policy of the in-house subcontractor, and the win-win relationship between the factory and in-house subcontractor was developed. The trade union did not oppose the idea that the expansion of in-house subcontracting contributed to corporate profits, the stability of employment of the members and maintenance of their working conditions. Since 2000, the steel factory has pursued the transformation of in - house subcontractors into subsidiaries, which has been supported by capital relations. By the way, since the mid-2000s, there has been an increase in the number of regular workers' employment. The major factors are as follows: more strengthened compliance with laws and regulations, the higher quality request of customers, stricter keeping of deadlines, and problem in recruiting of workers at in-house subcontract companies. The wage gap between the factory and in - house subcontracting was less at company B than at company S, and the wage level of in - house subcontracting was about 90% of the factory at company B. The relatively small gap at company B seems to be due to the union's movement of narrowing the gap, low market dominance and unfavorable labor market. The internal labor market has been formed in the in-house subcontracting, and the wage gap is not large, and the possibility of labor disputes is low. Industrial relations are stable in the in-house subcontract company as well as the factory. The stabilization of labor-management relations in the steel industry in Korea is required to reduce the wage gap between the factory and in-house subcontract enterprises by raising productivity and expanding the internal labor market at in-house subcontract enterprises.

Classification Algorithm-based Prediction Performance of Order Imbalance Information on Short-Term Stock Price (분류 알고리즘 기반 주문 불균형 정보의 단기 주가 예측 성과)

  • Kim, S.W.
    • Journal of Intelligence and Information Systems
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    • v.28 no.4
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    • pp.157-177
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    • 2022
  • Investors are trading stocks by keeping a close watch on the order information submitted by domestic and foreign investors in real time through Limit Order Book information, so-called price current provided by securities firms. Will order information released in the Limit Order Book be useful in stock price prediction? This study analyzes whether it is significant as a predictor of future stock price up or down when order imbalances appear as investors' buying and selling orders are concentrated to one side during intra-day trading time. Using classification algorithms, this study improved the prediction accuracy of the order imbalance information on the short-term price up and down trend, that is the closing price up and down of the day. Day trading strategies are proposed using the predicted price trends of the classification algorithms and the trading performances are analyzed through empirical analysis. The 5-minute KOSPI200 Index Futures data were analyzed for 4,564 days from January 19, 2004 to June 30, 2022. The results of the empirical analysis are as follows. First, order imbalance information has a significant impact on the current stock prices. Second, the order imbalance information observed in the early morning has a significant forecasting power on the price trends from the early morning to the market closing time. Third, the Support Vector Machines algorithm showed the highest prediction accuracy on the day's closing price trends using the order imbalance information at 54.1%. Fourth, the order imbalance information measured at an early time of day had higher prediction accuracy than the order imbalance information measured at a later time of day. Fifth, the trading performances of the day trading strategies using the prediction results of the classification algorithms on the price up and down trends were higher than that of the benchmark trading strategy. Sixth, except for the K-Nearest Neighbor algorithm, all investment performances using the classification algorithms showed average higher total profits than that of the benchmark strategy. Seventh, the trading performances using the predictive results of the Logical Regression, Random Forest, Support Vector Machines, and XGBoost algorithms showed higher results than the benchmark strategy in the Sharpe Ratio, which evaluates both profitability and risk. This study has an academic difference from existing studies in that it documented the economic value of the total buy & sell order volume information among the Limit Order Book information. The empirical results of this study are also valuable to the market participants from a trading perspective. In future studies, it is necessary to improve the performance of the trading strategy using more accurate price prediction results by expanding to deep learning models which are actively being studied for predicting stock prices recently.

Research Trends in The Journal of Daesoon Academy of Sciences : 『The Journal of Daesoon』 Vol.1-Vol.25 (1996~2015) (『대순사상논총』의 연구 동향에 관한 연구- 『대순사상논총』 1집-25집(1996~2015) -)

  • Chang, In-ho
    • Journal of the Daesoon Academy of Sciences
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    • v.27
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    • pp.201-243
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    • 2016
  • This paper analyzes the research trends from 358 scholarly articles published in the Journal of Daesoon Academy of Sciences from the first published journal in 1996 to the most recent journal published on the 25th of 2015 and proposes ideas for improvement. First of all, "The Journal of Daesoon Academy of Sciences" does not meet the standards required by the National Research Foundation, falling short of the most important conditions for the registration such as the periodicity and punctuality expected from academic journals. Furthermore, in terms of the Bibliometrical analysis, the number of articles published by the journal is decreasing and the consistency, with regards to rules and principles regulating publication details and bibliography formats, is nonexistent. Although various authors seemed to be meeting these criteria on the surface, the ratio of co-authored articles is too small. Securing researchers specializing in Daesoon Thought for expanding the size of the journal is important, but it is also important to diversify the research topics through exchanging ideas among researchers from various organizations. Here are some ideas for the improvement of the Journal of Daesoon Academy of Sciences: First, in order to meet the standards for punctuality and periodicity, it would be best to publish the journal twice a year with 12 to 15 articles. Second, the journal must become searchable through the creation of a database. Third, the key words and abstracts of articles must be written in Korean and English to facilitate the sharing of articles among researchers. Fourth, the journal must have a diverse and outstanding editorial board which takes into account the geographical situations of its board members. Fifth, the Journal must include articles on relevant topics that reflect the core topics of the Daesoon Thought and other studies. Sixth, articles must have a front page that contains bibliographical items to convey information to the reader. Seventh, it is essential that the journal have a clear publication date detailing the year, month, and day as well as a standard numbering scheme (i.e, Vol. and no).

Response of Potassium on Main Upland Crops (주요(主要) 전작물(田作物)에 대(對)한 가리성분(加里成分)의 비교(肥效))

  • Ryn, In Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.10 no.3
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    • pp.171-188
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    • 1977
  • The response and effect on main upland crops to potassium were discussed and summarized as follows. 1. Adequate average amounts of potash per 10a were 32kg for forage crop; 22.5kg for vegetable crops; 17.3kg for fruit trees; 13.3kg for potatoes; and 6.5kg for cereal crops. Demand of potassium fertilizer in the future will be increased by expanding the acreage of forage crops, vegetable crops and fruit trees. 2. On the average, optimum potash rates on barley, wheat, soybean, corn, white potato and sweet potato were 6.5, 6.9, 4.5, 8.1, 8.9, and 17.7kg per 10a respectively. Yield increaments per 1kg of potash per 10a were 4-5kgs on the average for cereal crops, 68kg for white potato, and 24kg for sweet potato. 3. According to the soil testing data, the exchangeable potassium in the coastal area was higher than that in the inland area and medium in the mountainous area. The exchangeable potassium per province in decreasing order is Jeju>Jeonnam>Kangweon>Kyongnam. Barley : 4. The response of barley to an adequate rate of potassium seemed to be affected more by differences in climatic conditions than to the nature of the soil. 5. The response and the adequate rate of potassium in the southern area, where the temperature is higher, were low because of more release of potassium from the soil. However, the adequate rate of phosphorus was increased due to the fixation of applied phosphorus into the soil in high temperature regions. The more nitrogen application would be required in the southern area due to its high precipitation. 6. The average response of barley to potassium was lower in the southern provinces than northern provinces. Kyongsangpukdo, a southern province, showed a relatively higher response because of the low exchangeable potassium content in the soil and the low-temperature environment in most of cultivation area. 7. Large annual variations in the response to and adequate rates of potassium on barley were noticed. In a cold year, the response of barley to potassium was 2 to 3 times higher than in a normal year. And in the year affected by moisture and drought damage, the responses to potassium was low but adequate rates was higher than cold year. 8. The content of exchangeable potassium in the soil parent materials, in increasing order was Crystalline Schist, Granite, Sedimentary and Basalt. The response of barley to potash occurred in the opposite order with the smallest response being in Crystalline Schist soil. There was a negative correlation between the response and exchangeable potassium contents but there was nearly no difference in the adequate rates of potassium. 9. Exchangeable potassium according to the mode of soil deposition was Alluvium>Residium>Old alluvium>Valley alluvium. The highest response to potash was obtained in Valley alluvium while the other s showed only small differences in responses. 10. Response and adequate rates of potassium seemed to be affected greatly by differences in soil texture. The response to potassium was higher in Sandy loam and Loam soils but the optimum rate of potassium was higher in Clay and Clay loam. Especially when excess amount of potassium was applied in Sandy loam and Loam soils the yield was decreased. 11. The application of potassium retarded the heading date by 1.7 days and increased the length of culm. the number of spikelet per plant, the 1,000 grain weight and the ratio of grain weight to straw. Soybean : 12. Average response of soybean to potassium was the lowest among other cereal crops but 28kg of grain yield was incrased by applying potash at 8kg/10a in newly reclaimed soils. 13. The response in the parent materials soil was in the order of Basalt (Jeju)>Sedimentay>Granite>Lime stone but this response has very wide variations year to year. Corn : 14. The response of corn to potassium decreased in soils where the exchangeable potassium content was high. However, the optimum rate of applied potassium was increased as the soil potassium content was increased because corn production is proportional to the content of soil potassium. 15. An interaction between the response to potassium and the level of phosphorus was noted. A higher response to potassium and higher rates of applied potassium was observed in soils contained optimum level of phosphorus. Potatoes : 16. White potato had a higher requirement for nitrogen than for potassium, which may imply that potato seems to have a higher capability of soil potassium uptake. 17. The yield of white potato was higher in Sandy loam than in Clay loam soil. Potato yields were also higher in soils where the exchangeable potassium content was high even in the same soil texture. However, the response to applied potassium was higher in Clay loam soils than in Sandy loam soils and in paddy soil than in upland soil. 18. The requirement for nitrogen and phosphorus by sweet potato was relatively low. The sweet potato yield is relatively high even under unfavorable soil conditions. A characteristics of sweet potatoes is to require higher level of potassium and to show significant responses to potassium. 19. The response of sweet potato to potassium varied according to soil texture. Higher yields were obtained in Sandy soil, which has a low exchangeable potassium content, by applying sufficient potassium. 20. When the optimum rate of potassium was applied, the yields of sweet potato in newly reclaimed soil were comparable to that in older upland soils.

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