• Journal of the Korean earth science society
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• v.34 no.3
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• pp.209-223
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• 2013

The purpose of this study was to estimate the contributed concentration of each emission source to $CH_4$ by verifying the simulated concentration of $CH_4$ in the Korean peninsula, and then to compare the $CH_4$ emission used to the $CH_4$ simulation with that of a box model. We simulated the Weather Research Forecasting-Community Multiscale Air Quality (WRF-CMAQ) model to estimate the mean concentration of $CH_4$ during the period of April 1 to 22 August 2010 in the Korean peninsula. The $CH_4$ emissions within the model were adopted by the anthropogenic emission inventory of both the EDGAR of the global emissions and the GHG-CAPSS of the green house gases in Korea, and by the global biogenic emission inventory of the MEGAN. These $CH_4$ emission data were validated by comparing the $CH_4$ modeling data with the concentration data measured at two different location, Ulnungdo and Anmyeondo in Korea. The contributed concentration of $CH_4$ estimated from the domestic emission sources in verification of the $CH_4$ modeling at Ulnungdo was represented in about 20%, which originated from $CH_4$ sources such as stock farm products (8%), energy contribution and industrial processes (6%), wastes (5%), and biogenesis and landuse (1%) in the Korean peninsula. In addition, one that transported from China was about 9%, and the background concentration of $CH_4$ was shown in about 70%. Furthermore, the $CH_4$ emission estimated from a box model was similar to that of the WRF-CMAQ model.

• Journal of the Korean Geographical Society
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• v.41 no.1 s.112
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• pp.106-120
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• 2006

Natural or man-made disaster has been expected to be one of the potential themes that can integrate human geography and physical geography. Typhoons like Rusa and Maemi caused great loss to insurance companies as well as public sectors. We have implemented a natural disaster management system for a private insurance company to produce better estimation of hazards from high wind as well as calculate vulnerability of damage. Climatic gauge sites and addresses of contract's objects were geo-coded and the pressure values along all the typhoon tracks were vectorized into line objects. National GIS topog raphic maps with scale of 1: 5,000 were updated into base maps and digital elevation model with 30 meter space and land cover maps were used for reflecting roughness of land to wind velocity. All the data are converted to grid coverage with $1km{\times}1km$. Vulnerability curve of Munich Re was ad opted, and preprocessor and postprocessor of wind velocity model was implemented. Overlapping the location of contracts on the grid value coverage can show the relative risk, with given scenario. The wind velocities calculated by the model were compared with observed value (average $R^2=0.68$). The calibration of wind speed models was done by dropping two climatic gauge data, which enhanced $R^2$ values. The comparison of calculated loss with actual historical loss of the insurance company showed both underestimation and overestimation. This system enables the company to have quantitative data for optimizing the re-insurance ratio, to have a plan to allocate enterprise resources and to upgrade the international creditability of the company. A flood model, storm surge model and flash flood model are being added, at last, combined disaster vulnerability will be calculated for a total disaster management system.

• Economic and Environmental Geology
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• v.4 no.4
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• pp.167-215
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• 1971

I. Purpose and Importance of the Study The purpose of the present study is to clarify to geological, mineralogical, and physico-chemical properties of the clay minerals deposits imbedded in the Tertiary sediments in the areas between. Pohang and Ulsan along southeastern coastal region of Korea. These clays are being mined and utilized for filter and insecticide after activation or simple pulverizing, nontheless activated clays are short coming as chemical industry in Korea has been rapidly grown in recent years. In spite of such increase in clay demand, no goological investigation on clay deposits nor physico-chemical properties of the clays have been carried out up to date. Consequently activated clays produced in Korea is not only of low grade but also of shortage in supply, so that Korea has to import activated clays of better grade. The importance of the present study lies, therefore, on that guiding principle could be laid down by knowing stratigraphical horizons, of clay deposits and fundamental data of improving grade of activated clays might be derived from the results of physico-chemical examinations. II. Contents and Scope of the study The contents of the study are pinpointed down in the following two subjects: 1) General geological investigation of Tertiary formations distributed in the areas between Pohang and UIsan, and detail geological study of the bentonitic clay deposits imbedded in them. 2) To clarifty physico-chemical characteristics of the clays by means of chemical analysis, X-ray diffraction and electron microscope. The scope of the study involves the following there points: i) Regional geological investigation-This investigation has been carried out in order to find out the distribution of Tertiary sediments and exact location of clay mineral deposits in the areas between Pohang and UIsan. ii) Detail geological investigation-This has been concentrated in and around the clay deposits which. had been found out by the regional investigation. iii) Laboratory researchs include i) age determination and correlation of Tertiary sediments by paleontological study, and ii) Chemical analysis, X-ray diffraction, and electron microscopic studies on clays, samples taken from various clay deposits. III. Research Results and Suggestions 1) The geology of the area investigated is composed mainly of Janggi and Beomgokri groups of Miocene age in ascending order rested on the upper Silla system, Balkuksa granite and volcanic rocks of upper Cretaceous age as base. 2) Janggi group is composed in ascending order of Janggi conglomerate, Nultaeri rhyolitic tuff, Keumkwangdong shale, two beds of lignite-bearing formations which consist of alternation of conglomerate, sandstone and mudstone, and andesitic, rhyolitic, and basaltic tuff beds. 3) Beomgokri group is mainly composed of andesitic to rhyolitic tuff interlayered by conglomerate and tuffaceous sandstone. In the areas around boundary between North-and South Kyeongsang-do is distributed Haseori farmation which is composed of conglomerate, sandstone, mudstone and andesitic to rhyolitic tuff, and which is correlated to Eoilri formation of Janggi group. 4) Clay deposits of the area are interbedded in Eoilri, Haseori, Nultaeri tuff, Keumkwangdong shale, upper and lower horizon of the lower lignite-bearing seam, and Keumori rhyolitic tuff formations of Janggi group; and are genetically classi.fied into four categories, that is, i) those derived from volcanic ash beds(Haseori and Daeanri deposits), ii) those of secondary residual type from rhyolitic tuff beds(Seokupri deposits), iii) Clay beds above and beneath the lignite seams, (Janggi and Keumkwangdong deposits), and iv) those derived from rhyolitic tuff beds(Sangjeong and Tonghae deposits). 5) Mineral constituents of clay deposits are, according to X-ray diffraction, montmorillonite accompanied in different degree by cristobalite, plagioclase, quartz, stilbite, and halloysite in rare occasion. The clays are grouped according to mineral composition into four types; i) those consist mostly of montmorillonite, ii) those composed of montmorillonite and cristobalite, iii) those composed of montmorillonite and plagioclase, and iv) those composed of montmorillonite, plagioclase and quartz. 6) Clays interbedded in Haseori formation and vicinity of lignite seams belong to the first type, are of good quality and derived either from volcanic ash bed, or primary clay beds near lignite seams. Clays belonged to other types are derived from weathering of rhyolitic tuff formations and their quality varies depending upon original composition and degree of weathering. Few clays in secondary residual type contain small amount of halloysite. 7) Judging from analytical data, content of silica($SiO_2$) varies proportionally with content of cristobalite, and alumina($Al_2O_3$) content does not vary with that of plagioclase, but increases in the sedimentary bedded type of deposits. 8) It is unknown whether or not these days could be upgraded by beneficiation since no grain size of these impurities nor beneficiation test had been studied. 9) Clay beds derived from valcanic ash layers or sedimentary layers at the vicinity of lignite seams are thin in thickness and of small, discontinueous lenticular shape, although they are of good quality; and those derived from rhyolitic tuff formations or residual type from tuff are irregular in both occurrence and quality. It is, therefore, not only very difficult but also meaningless to calculate its reserve, and reserve estimation, even if done, will greatly be deviated from practically minable one. Consequently, way of discovery and exploitation of clay deposits in the area under consideration is to check the geologically favorable areas whenever needed.

• Tuberculosis and Respiratory Diseases
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• v.40 no.5
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• pp.575-583
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• 1993

Background: Mediastinal masses are not uncommon, and an overall incidence of one case per 100,000 population per year in individuals of all ages and with no difference in sex incidence may be a reasonable estimation. At least half of all mediastinal masses are asymptomatic and this proportion has increased in recent decades with wider use of screening chest roentgenography. Symptoms in patients with mediastinal mass lesions are usually due to compression or invasion of nearby intrathoracic structures. Most mediastinal mass lesions have characteristic predilectional locations. The basic focus of diagnostic evaluation is an orderly preparation for obtaining a tissue diagnosis but even lesions discovered to be benign must generally be removed. Seldom is this status known for certain preoperatively. In additaion, benign tumors may continue to enlarge, thus compromising vital organs; they may rupture, hemorrhage, become infected or have the possibility of various malignant degeneration. Therefore, all mediastinal masses must be surgically removed whether they are malignant or benign. Methods: We reviewed the medical records of 344 cases previously confirmed as mediastinal tumors or cysts from January, 1960 to August, 1992 and investigated the clinical findings. Results: Neurogenic tumors were the most common(24.7%) and thymomas were distinctively increased recently. Overall ratio between males and females was 1.1:1 and age distribution was relatively even among all age groups. Predilectional sites were posterior for neurogenic tumors, and anterior for teratodermoid tumors, thymomas and lymphomas. Dyspnea was the most common symptom in the patients of the mediastinal tumors and asymptomatic patients were 19.5%, Benign mediastinal mass lesions were 66.0% and malignant, 34.0%, Complete or partial resection was done in 42.4%. Conclusion: We could find the increasing incidence and the tendency of aggressive resection as possible in the mediastinal tumors. We expect the discovery of more mediastinal tumors with wider use of regular check-up and development of diagnostic methods.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.4
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• pp.176-184
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• 2011

Cold air on sloping surfaces flows down to the valley bottom in mountainous terrain at calm and clear nights. Based on the assumption that the cold air flow may be the same as the water flow, current models estimate temperature drop by regarding the cold air accumulation at a given location as the water-like free drainage. At a closed catchment whose outlet is blocked by man-made obstacles such as banks and roads, however, the water-like free drainage assumption is no longer valid because the cold air accumulates from the bottom first. We developed an empirical model to estimate quantitatively the effect of cold pool on nocturnal temperature in a closed catchment. In our model, a closed catchment is treated like a "vessel", and a digital elevation model (DEM) was used to calculate the maximum capacity of the cold pool formed in a closed catchment. We introduce a topographical variable named "shape factor", which is the ratio of the cold air accumulation potential across the whole catchment area to the maximum capacity of the cold pool to describe the relative size of temperature drop at a wider range of catchment shapes. The shape factor is then used to simulate the density profile of cold pool formed in a given catchment based on a hypsometric equation. The cold lake module was incorporated with the existing model (i.e., Chung et al., 2006), generating a new model and predicting distribution of minimum temperature over closed catchments. We applied this model to Akyang valley (i.e., a typical closed catchment of 53 $km^2$ area) in the southern skirt of Mt. Jiri National Park where 12 automated weather stations (AWS) are operational. The performance of the model was evaluated based on the feasibility of delineating the temperature pattern accurately at cold pool forming at night. Overall, the model's ability of simulating the spatial pattern of lower temperature were improved especially at the valley bottom, showing a similar pattern of the estimated temperature with that of thermal images obtained across the valley at dawn (0520 to 0600 local standard time) of 17 May 2011. Error in temperature estimation, calculated with the root mean square error using the 10 low-lying AWSs, was substantially decreased from $1.30^{\circ}C$ with the existing model to $0.71^{\circ}C$ with the new model. These results suggest the feasibility of the new method in predicting the site-specific freeze and frost warning at a closed catchment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.3
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• pp.41-48
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• 1965

This study was aimed at knowing the magnitude of year variation in rice heading dates under the different seasonal cultures, and to estimate the heading date in advance. Using six rice varieties such as Kwansan, Suwon＃82, Suwon ＃144, Norin＃17, Yukoo＃132 and Paltal, the early, ordinary and late seasonal cultures had been carried out at Paddy Crop Division, Crop Experiment Station at Suwon for the six-year period 1959 to 1964. In addition the data of the standard rice cultures at the Provincial Offices of Rural Development for the 12-year period 1953 to 1954, were analyzed for the purpose of clarifying a relationship between variation of rice heading dates and some of meteorological data related to the locations and years. The results of this study are as follows: 1. Year variation of rice heading dates was as high as 14 to 21 days in the early seasonal culture and 7 to 14 days in the ordinary seasonal culture, while as low as one to seven days in the late seasonal culture which was the lowest among three cultures. The magnitude of variation depended greatly on variety, cultural season and location. 2. It was found out that there was a close negative correlation between the accumulated average air temperature for 40 days from 31 days after seeding and number of days to heading in the early seasonal culture. Accordingly, it was considered possible to predict the rice heading date through calculation of the accumulated average air temperature for the above period and then the linear regression(Y=a+bx). On the other hand, an estimation of the heading date in the late seasonal culture requires for the further studies. In the ordinary seasonal culture, no significant correlation between the accumulated average air temperature and number of days to heading was obtained in the six-year experiments conducted at Suwon. There was a varietal difference in relationship between the accumulated average air temperature for 70 days from seeding and number of days to heading in the standard cultures at the provincial offices of rural development. Some of varieties showed a significant correlation between two factors while the others didn't show any significant correlation. However, there was no regional difference in this relationship.

• Journal of Chest Surgery
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• v.31 no.5
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• pp.488-493
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• 1998

In the preoperative evaluation before coronary artery bypass surgery, review of the coronary arteriogram is the most important step. Expected "normal" lumen diameter at a given coronary anatomic location is a basis for quantative estimation of coronary disease severity that could be more useful than the traditional "percent stenosis". The distribution and number of major coronary artery branches are determinants of number of bypass grafts needed. We reviewed the coronary artery anatomy in 174 adult patients who revealed no coronary pathology in angiographic studies done from September 1994 to June 1996. Quantative analysis was done in all cases by a single person using a Computerized System (Arripro 35ⓡ). The results were follows; 1) The mean diametre of left main coronary artery was 4.45 mm(range 2.74~6.72). The pattern of branching was bifurcation in 67.24%, trifurcation in 28.74% and quadrifurcation in 4.02% of the patients. 2) The mean diametre of left anterior descending artery was 3.17 mm(range 2.10~5.85), 2.79 (range 1.55~5.59) and 2.17 mm(range 1.37~3.81) in the proximal, mid, and the distal portions, respectively. The number of diagonal branches of left anterior artery was from one to four(mode=2). 3) The mean diametre of proximal and distal left circumflex artery were 3.17mm(range 1.74~4.89) and 2.19 mm(range 1.21~4.46). The number of obtuse marginal branches of left circumflex artery is from one to six(mode 2). 4) The mean diametre of proximal and distal right coronary artery, the posterior descending artery and the largest posterolateral branch were mean 3.51 mm(range 2.07~5.67), 2.09 mm (range 1.42~3.60), 2.09 mm(range 1.02~3.60) and 2.30 mm(range 1.39~4.39). 5) The right coronary artery dominant was 163 cases(93.68%) of the total 174 cases. 6) The large significant acute marginal artery was visualized in more than half of the people. half of the people.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.6
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• pp.256-268
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• 2016

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2015. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering were carried out in the areas of flow, heat and mass transfer, cooling and heating, and air-conditioning, the renewable energy system and the flow inside building rooms. Research issues dealing with air-conditioning machines and fire and exhausting smoke were reduced. CFD seems to be spreading to more research areas. (2) Research works on heat transfer area were carried out in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the economic analysis of GHG emission, micro channel heat exchanger, effect of rib angle on thermal performance, the airside performance of fin-and-tube heat exchangers, theoretical analysis of a rotary heat exchanger, heat exchanger in a cryogenic environment, the performance of a cross-flow-type, indirect evaporative cooler made of paper/plastic film. In the area of pool boiling and condensing, the bubble jet loop heat pipe was studied. In the area of industrial heat exchangers, researches were performed on fin-tube heat exchanger, KSTAR PFC and vacuum vessel at baking phase, the performance of small-sized dehumidification rotor, design of gas-injection port of an asymmetric scroll compressor, effect of slot discharge-angle change on exhaust efficiency of range hood system with air curtain. (3) In the field of refrigeration, various studies were carried in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, a cold-climate heat pump system, $CO_2$ cascade systems, ejector cycles and a PCM-based continuous heating system were investigated. In the alternative refrigeration/energy system category, a polymer adsorption heat pump, an alcohol absorption heat pump and a desiccant-based hybrid refrigeration system were investigated. In the system control category, turbo-refrigerator capacity controls and an absorption chiller fault diagnostics were investigated. (4) In building mechanical system research fields, eighteen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the user and location awareness technology applied dimming lighting control system, the lighting performance evaluation for light-shelves, the improvement evaluation of air quality through analysis of ventilation efficiency and the evaluation of airtightness of sliding and LS window systems. The subjects of building energy were worked on the energy saving estimation of existing buildings, the developing model to predict heating energy usage in domestic city area and the performance evaluation of cooling applied with economizer control. The studies were also performed related to the experimental measurement of weight variation and thermal conductivity in polyurethane foam, the development of flame spread prevention system for sandwich panels, the utilization of heat from waste-incineration facility in large-scale horticultural facilities.

• Korean Journal of Heritage: History & Science
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• v.51 no.1
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• pp.80-99
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• 2018

In premodern society, the central spaces in local counties were known as Eupchi (邑治), in which Gwan-a (官衙). The Eupchi located in seaside counties were in Eupseong, whereas the Eupchi of inland counties only included a Gwan-a, and did not have a fortress. Yanggeun-gun (楊根郡) and Jipyeonghyeon (砥平縣), which currently form Yangpyeong-gun (楊平郡), were counties where only Gwan-a existed. At present, there are few traces of the Gwan-a in Yanggeun and Jipyeong. In addition, it is impossible to exactly verify the history, scale and location of these two Gwan-as. Therefore, this study attempts to make a rough estimation of the histories, scales and sites of these Gwan-a by analyzing the relevant literature and ancient maps that are scattered according to the principles of spatial organization of local Gwan-a. The Yanggeun and Jipyeong Gwan-a appear to have been built in the early Joseon period. There are three reasons for this assertion: First, in Yanggeun and Jipyeong, Suryeong (守令) were first officially appointed after the early Joseon period. Once Suryoeng were appointed to such counties, the Gwan-a in which they would serve could be established. Second, the Dongheon (東軒) in Yanggengun and the Gaeksa (客舍) in Jipyeonghyeon were rebuilt in 1703 (29th year of the reign of King Sukjong) and 1465 (11th year of the reign of King Sejo), respectively; thus; the Gwan-a must have existed since the early Joseon period.. Third, in Yanggeungun, the Hyanggyo (鄕校) had existed since the early Joseon period, as the Joseon government necessarily established the Hyanggyo in areas where Suryeong were established. The facilities of local Gwan-a in the Joseon period were largely divided into gonghae (公?), educational institutes, and alters. The gonghae was a facility in which the Suryeong and Gwanwon (官員) managed administrative, judicial and military affairs, and consisted of the A-sa (衙舍), Hyeongcheong (鄕廳), Jackcheong (作廳), Gaeksa (客舍), Gungwancheon (軍官廳), and so on. The education institute was called a Hyeonggyo, while alters included the Sajikdan (社稷壇), Seonghwansa (城隍祠) and Yeodan (?壇). Both the Yeongeun and Jipyeong Gwan-a also consisted of such facilities as A-sa, Hyangcheong, Jakcheong, Gaeksa, Gungwancheong, Hyeonggyo, Changgo, Sajikdan, Seonghwangsa, Yeodan, Saryeongcheong, Jiincheong and Gwannocheong. The present sites for both Gwan-as cannot be identified with any certitude. However, they can be roughly identified by connecting the related literatures, oral statements and relics with the principles of spatial organization of local Gwan-a in the Joseon period. ${\bullet}$ Address of the Yanggeun A-sa (Dongheon): the whole of # 15, Gwanmun 1-gil, Yangpyeong-eup (Yanggeun-ri 151) in front of Yanggeun Junior High School at present. ${\bullet}$ Address of Yanggeun Gaeksa: around the Yangpyeong police station at present. ${\bullet}$ Address of Jipyeong A-sa(Dongheon): the whole of Jipyeong-ri 248-250, Jipyeong-myeon at present. ${\bullet}$ Address of Jipyeong Gaeksa: the whole of Jipyeong-ri 238, Jipyeong-myeon at present.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.848-857
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• 2018

Recently, around the world, active development of new renewable energy sources including solar power, waves, and fuel cells, etc. has taken place. Particularly, floating offshore wind farms have been developed for saving costs through large scale production, using high-quality wind power and minimizing noise damage in the ocean area. The development of floating wind farms requires an evaluation of the Maritime Safety Audit Scheme under the Maritime Safety Act in Korea. Floating wind farms shall be assessed by applying the line and area concept for systematic development, management and utilization of specified sea water. The development of appropriate evaluation methods and standards is also required. In this study, proper standards for marine traffic surveys and assessments were established and a systemic treatment was studied for assessing marine spatial area. First, a marine traffic data collector using AIS or radar was designed to conduct marine traffic surveys. In addition, assessment methods were proposed such as historical tracks, traffic density and marine traffic pattern analysis applying the line and area concept. Marine traffic density can be evaluated by spatial and temporal means, with an adjusted grid-cell scale. Marine traffic pattern analysis was proposed for assessing ship movement patterns for transit or work in sea areas. Finally, conceptual design of a Marine Traffic and Safety Assessment Solution (MaTSAS) was competed that can be analyzed automatically to collect and assess the marine traffic data. It could be possible to minimize inaccurate estimation due to human errors such as data omission or misprints through automated and systematic collection, analysis and retrieval of marine traffic data. This study could provides reliable assessment results, reflecting the line and area concept, according to sea area usage.