• Explosives and Blasting
• /
• v.30 no.2
• /
• pp.86-97
• /
• 2012

Ground vibration induced by a bench blasting in the construction site should cause the damage to the structure and indirect damage to a human body, and the vibration level is most practical descriptor for regulating the damage to human body and peak particle velocity is the descriptor for direct damage assesment of the structure. Meantime, the vibration level has not been considered for the blasting design but this study is the case that apply not only peak particle velocity but also vibration level on the blasting design. Also, we strongly believe that this study will be helpful for the management in the blasting site which some civil appeal is concerned. Total 232 measurements of both ppv and vibration level was used to estimate the scale distance. When the regulating threshold was ppv 0.3 cm/s and vibration level 75 decibel, the charge per delay to be estimated with vibration level could be recommended by 1.2~1.4 times than it of ppv. So, it is proven that considering vibration level on the blasting design is reasonable for not only prevention of the civil appeals but also effective blasting. Again, the blasting design which follows the law, "Noise and Vibration Control Act" can actually serve good condition to carry much more economical and effective blasting. The instruments used for this study are the SV-1 model, as first instrument in korea which can measure vibration velocity and vibration level at the same time.

• The Journal of Industrial Distribution & Business
• /
• v.2 no.2
• /
• pp.5-14
• /
• 2011

Opening agricultural market expansion, reduced purchases through wholesale markets, expanding the influence large retailers of consumer's market such as changes in the distribution system to the farmer's market conditions are changing rapidly. Because of this, retailers of the scaled and chain-store operations was centered on distribution environmental changes of the consumer market place. In producing area due to changes in market conditions in the agricultural production of in producing area distribution organization and the size distribution can not be put off no longer challenge is imminent. If it do not raise forces banded together, the producer is bound to remain as the weak. To support the distribution of this production was introduced in 2000 enable the Activation Project of in producing area distribution. Recent in producing area Changes of Agricultural conditions in order to cope with the Small-scale farmers and small individual farmers are becoming Scaled and specialized. Also, is specific to each item and regional is showing aspects. Government support for Activation Project of in producing area distribution is greatly improved, but in terms of competitiveness on the market still is showing the limitations. The most common of these problems, the market response if in producing area producer's organization and scale of the problem. Equipped for the purpose of consumer market place responsiveness unreasonable propelled outward from the Painter-sized weakens the organizational power. also, Difficult to succeed organizational size is a dissolution or anything within a few years, farmers around the best producer organizations, such as deviation occurs is exposed to a variety of issues. In this study, previous studies refer to the recent changes in agricultural retail environment, background and needs of organization·scaled, Determine the status of the domestic in producing area organizations and derived Problems, look into Domestic and overseas of in producing area organization with best practices for enhancing the competitiveness of the proposed improvement are intended to. In the future, in producing area distribution policy would like to provide direction to the development. The results of the study showed the follwing : 1) enhance utilization and orrganized through the diversification of the agricultural Collection systems. 2) Scaled to achieve through Items of specialized a wide area marketing. 3) Management operating units, such as installation and operating that overseas the best practices " Comite Economique Agricole Regional 'Fruits et Legumes' de Bretagne". 4) To establish a support system that in producing area distribution organization model development for appropriate domestic. In particular, in case of domestic in producing area distribution organization, through the analysis of various case study that a successful organization and scaled. The process of the various challenges arising in organizational scaled and generalization, and by the way he goes about trying to overcome is required. At the end of the study's limitations and future research directions suggested.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.8 no.4
• /
• pp.311-318
• /
• 2010

U. S. NRC Regulation Guide 1.52 regulating ESF ACS in nuclear power plants has been revised to revision 3. To apply reduction of operability test time, allowance of alternative challenge agents for in-place leak test of HEPA filters, and upgrade of Methyl Iodide penetration acceptance criterion in activated carbon performance test suggested in Reg. Guide 1.52(Rev.3) on Yonggwang units 5 and 6 ESF ACSes, technical feasibility study was carried out with on-site experiments as well as experiments with a lab-scale model. It was confirmed that the moisture in the system returned to the level before the test in 1 or 4 days even though the moisture was removed during the operability test lasting more than 10 hours. Therefore, it is appropriate to perform monthly operability test in 15 minutes just long enough to check the operability of equipment. To change challenge material for in-place HEPA filter leak test, size of aerosol, production rate, and leak detection capability were compared for DOP and PAO. It was concluded that PAO can be substituted for DOP in nuclear power plants. The upgrade of Methyl Iodide penetration acceptance criterion from 0.175 % to 0.5 % in active carbon filter bed deeper than 4 inches was to conform to the change of activated carbon performance test method to ASTM D3803(1989). It was confirmed that Methyl Iodide penetration acceptance criterion of 0.5 % under $30^{\circ}C$, relative humidity 95 % condition was conservatively good enough for testing performance of active carbon insitu. The licence change of Yonggwang units 5 and 6 has been completed based on this study.

• Journal of the Korean Geographical Society
• /
• v.40 no.3 s.108
• /
• pp.253-273
• /
• 2005

In recent years, there are strong social demands to characterize the spatial distribution of mountains in Korea. This study aims to develop a 'Sanjulgi-Jido(mountain ridge map)' that might be used not only to satisfy these social demands but also to effectively present the spatial distribution of mountains and drainage basins in the Korean Peninsular. The 'Sanjulgi-Jido' developed in this study is a map that presents the continuity of mountains based on the drainage divides that are delineated by a pre-defined drainage basin size and elevation. This study first validated the Bakdudaegan system through the analyses of a digital elevation model. The Bakdudaegan system has long been recognized as the Koreans traditional conceptual framework to characterize the spatial distribution of mountains. The analyses showed that the Bakdudaegan system has several problems to represent the mountain systems in Korea, which includes 1) the lack of the representativeness of drainage basins, 2) inaccuracy to depict the boundary of drainage basins, 3) the lack of representativeness of mountains, and 4) geo-polical issue that confines the spatial extent of mountain systems within the Korean Peninsular. In order to represent the mountains system in a more quantitative manner, we applied several terrain analysis techniques to understand the spatial distribution of mountains and drainage basins. Based on these analyses, we developed an hierarchical system to classify the continuity (If mountains, which are presented as the spatial distribution of drainage divides with a certain elevation. The first-order Sanjulgi is the drainage divides whose drainage basin are bigger than $5,000km^2$ and the point elevation is above 100m. The next order Sanjulgi is delineated as the size of drainage basin is successively divided by two. This kind of design is able to provide a logical framework to present the mountain systems at different details, depending on the purpose and scale of maps. We also provide several empirical functions to calculate various geomorphological indices for each order of Sanjulgi. The 'Sanjulgi Jido' is similar with the Bakdudaegan system, since it characterizes the continuity of mountains based on the spatial distribution of the drainage divide. It, however, has more scientific criteria to define the scale and continuity of mountains. It should be also noted that the 'Sanjulgi Jido' proposed has different logical and methodological background, compared with the mountain range map that explains the genesis of mountain systems in addition to the continuity of mountains.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.9 no.1
• /
• pp.1-16
• /
• 2007

The use of information on natural resources is indispensable to most agricultural activities to avoid disasters, to improve input efficiency, and to increase lam income. Most information is prepared and managed at a spatial scale called the "Hydrologic Unit" (HU), which means watershed or small river basin, because virtually every environmental problem can be handled best within a single HU. South Korea consists of 840 such watersheds and, while other watershed-specific information is routinely managed by government organizations, there are none responsible for agricultural weather and climate. A joint research team of Kyung Hee University and the Agriculture, forestry and Fisheries Information Service has begun a 4-year project funded by the Ministry of Agriculture and forestry to establish a watershed-specific agricultural weather information service based on "high definition" digital climate maps (HD-DCMs) utilizing the state of the art geospatial climatological technology. For example, a daily minimum temperature model simulating the thermodynamic nature of cold air with the aid of raster GIS and microwave temperature profiling will quantify effects of cold air drainage on local temperature. By using these techniques and 30-year (1971-2000) synoptic observations, gridded climate data including temperature, solar irradiance, and precipitation will be prepared for each watershed at a 30m spacing. Together with the climatological normals, there will be 3-hourly near-real time meterological mapping using the Korea Meteorological Administration's digital forecasting products which are prepared at a 5 km by 5 km resolution. Resulting HD-DCM database and operational technology will be transferred to local governments, and they will be responsible for routine operations and applications in their region. This paper describes the project in detail and demonstrates some of the interim results.

• Journal of Korea Water Resources Association
• /
• v.54 no.9
• /
• pp.731-745
• /
• 2021

In this study, the monthly temperature of the Han River basin was predicted by statistical multiple regression models that use global climate indices and weather data of the target region as predictors. The optimal predictors were selected through teleconnection analysis between the monthly temperature and the preceding patterns of each climate index, and forecast models capable of predicting up to 12 months in advance were constructed by combining the selected predictors and cross-validating the past period. Fore each target month, 1000 optimized models were derived and forecast ranges were presented. As a result of analyzing the predictability of monthly temperature from January 1992 to December 2020, PBIAS was -1.4 to -0.7%, RSR was 0.15 to 0.16, NSE was 0.98, and r was 0.99, indicating a high goodness-of-fit. The probability of each monthly observation being included in the forecast range was about 64.4% on average, and by month, the predictability was relatively high in September, December, February, and January, and low in April, August, and March. The predicted range and median were in good agreement with the observations, except for some periods when temperature was dramatically lower or higher than in normal years. The quantitative temperature forecast information derived from this study will be useful not only for forecasting changes in temperature in the future period (1 to 12 months in advance), but also in predicting changes in the hydro-ecological environment, including evapotranspiration highly correlated with temperature.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.35 no.4
• /
• pp.90-104
• /
• 2007

Landmarks like high-rise building are one of the important elements for the enhancement of city identity and provides the hierarchy of city streets, playing a central and symbolic role in cities. Research on physical attribute of landmarks, such as height, distance, location and shape, which are suitable for a city scale, can help a city create a distinct image and maintain comprehensible structure. To achieve this purpose, it is necessary to understand the spatial and cognitive characteristics of a landmark for the establishment and management of it. The results of this study can be summarized as follows: 1. The level of representativeness of a landmark increases in proportion to the degree of cognitive intensity on it. The relation between representativeness and cognitive intensity can be explained as the log-function as follows: Log(the number of people who respond "It has representativeness")=$-1.2579+1.5908{\times}$(cognitive intensity); 2. There are a few differences based on the attributes of respondents: while gender has no distinct influence, residential period and age show statistically meaningful influence on cognitive intensity of a vertical landmark Cognitive intensity of an individual landmarks especially, differs according to the class of main users. Because of frequent changes in occupation or employment, respondents consider the distance from a residential area more important than the distance from a working area in evaluating cognitive intensity of landmarks; 3. landmark can be classified into two kinds: a district landmark and an urban landmark A district landmark is closely connected with physical attributes of the landmark itself, such as distance, size and height. An urban landmark is mainly related to cognitive attributes such as the image and identity of a city as a whole. As a result, the landmark analysis data in this research provides spatial order and identity in a city. It is difficult to establish and reinforce the image of a city as a single element ike a landmark. However, withy steady follow-up research, this study could be seen as a systematic and logical model to improve urban landscape and image.

• Health Policy and Management
• /
• v.5 no.1
• /
• pp.80-105
• /
• 1995

Assuming that we introduced integration of medical insurance society for self-employed, this study was conducted to examine effects and results after the integration and to research more effective method for integration. To assess effects and results of the finacial status of 266 insurance societies after intergration, the data were obtained from "The Medical Insurance Program for Self-Employeds Statistical Yearbook in 1992". The major finding are as follows : 1. Three alternative integration proposals were made. First alternative proposal was consisted of 232 medical insurance societies, second was 187, and third was 115. 2. As the results of average number of the insured per insurance societies of medical insurance program for self-employed every alternative proposal, first was 88, 119 persons, second was 108, 576, and third was 178, 967 from 76, 576 persons of present socienties. 3. It was true that the more average size of societies increased, the more average administration expenditure per 1, 000 insured reduced. 4. The average size of societies grew bigger, the rate of general expenditure to general revenue more improved. Also, the rate of benefits to contributions was changed for better. But if not to have had correct analysis and precise preparation for integration, effects and results of integration were always not optiized. 5. According to results of simple regression formulas, it was proved that the more the average size of societies was increased, the more result was advantaged. 6. The law of majority and the economy of scale were applied in this study, and it was necessary to analyze and assess effectiveness and efficiency of integration. Therefore, when the integration of medical insurance societies for self-employeds will be performed, it must be taken into consideration. Among three alternative proposals, third was showed more effective alternative than anothe, second was presented more ineffective result than present system. To achieve more effective and efficient integration of regional medical insurance societies throughout the result of the regression formula on present cost curve, it is necessary to operate well-integrated societies and to know appropriative countermeasures of present situation of each societies. Also, for integrating regional medical insurance societies, it is necessary to continue more deep research through practical model activity and to investigate the effective size and managed method of the societies.societies.

• The Mathematical Education
• /
• v.27 no.1
• /
• pp.15-23
• /
• 1988

We are at the onset of a major revolution in education, a revolution unparalleled since the invention of the printing press. The computer will be the instrument of this revolution. Computers and computer application are everywhere these days. Everyone can't avoid the influence of the computer in today's world. The computer is no longer a magical, unfamiliar tool that is used only by researchers or scholars or scientists. The computer helps us do our jobs and even routine tasks more effectively and efficiently. More importantly, it gives us power never before available to solve complex problems. Mathematics instruction in secondary schools is frequently perceived to be more a amendable to the use of computers than are other areas of the school curriculum. This is based on the perception of mathematics as a subject with clearly defined objectives and outcomes that can be reliably measured by devices readily at hand or easily constructed by teachers or researchers. Because of this reason, the first large-scale computerized curriculum projects were in mathematics, and the first educational computer games were mathematics games. And now, the entire mathematics curriculum appears to be the first of the traditional school curriculum areas to be undergoing substantial trasformation because of computers. Recently, many research-Institutes of our country are going to study on computers in orders to use it in mathematics education, but the study is still start ing-step. In order to keep abreast of this trend necessity, and to enhance mathematics teaching/learning which is instructed lecture-based teaching/learning at the present time, this study aims to develop/present practical method of computer-using. This is devided into three methods. 1. Programming teaching/learning method This part is presented the following five types which can teach/learn the mathematical concepts and principle through concise program. (Type 1) Complete a program. (Type 2) Know the given program's content and predict the output. (Type 3) Write a program of the given flow-chart and solve the problem. (Type 4) Make an inference from an error message, find errors and correct them. (Type 5) Investigate complex mathematical fact through program and annotate a program. 2. Problem-solving teaching/learning method solving This part is illustrated how a computer can be used as a tool to help students solve realistic mathematical problems while simultaneously reinforcing their understanding of problem-solving processes. Here, four different problems are presented. For each problem, a four-stage problem-solving model of polya is given: Problem statement, Problem analysis, Computer program, and Looking back/Looking ahead. 3. CAI program teaching/learning method This part is developed/presented courseware of sine theorem section (Mathematics I for high school) in order to avail individualized learning or interactive learning with teacher. (Appendix I, II)

• Journal of vocational education research
• /
• v.37 no.5
• /
• pp.1-23
• /
• 2018

The purpose of this study was to explore the direction of school system reorganization in order to strengthen the educational competitiveness of Meister high school. Specifically, the first one was to review prior research related to the school system reorganization of vocational education at the secondary level, and to propose school system reorganization plans of Meister high school. And second one was to analyze the perceptions of related parties about this reorganization plans and to derive important implications. The results of this study were as follows. First, based on the results of the analysis of precedent research, school system reorganization plans of Meister high school was composed of (1) introduction of credit system, (2) introduction of 3-semester system, and (3) expansion of school year. Second, as a result of the questionnaire survey conducted by 138 Meister high school teachers and 185 Meister high school graduates, both group seemed to agree on the necessity of school system reorganization of Meister high school. In addition, the necessity of introducing the proposed reorganization plans was more than a certain level, but the applicability was recognized as somewhat lower than the necessity of introduction. Third, the results of the FGI analysis on industrial personnel showed a positive response, especially regarding the operation of advanced course due to the expansion of school year. Based on this results, it was proposed to design a more systematic reorganization model and provide policy support, to examine the whole scale expansion through pilot application, and to collect opinions more systematically from industrial field experts on school system reorganization plans.