• Korean Journal of Remote Sensing
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• v.33 no.5_3
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• pp.855-866
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• 2017

Several research cases using remote sensing methods to analyze changes of storage and dynamics of groundwater aquifer were reviewed in this paper. The status of groundwater storage, in an area with regional scale, could be qualitatively inferred from geological feature, surface water altimetry and topography, distribution of vegetation, and difference between precipitation and evapotranspiration. These qualitative indicators could be measured by geological lineament analysis, airborne magnetic survey, DEM analysis, LAI and NDVI calculation, and surface energy balance modeling. It is certain that GRACE and InSAR have received remarkable attentions as direct utilization from satellite data for quantification of groundwater storage and dynamics. GRACE, composed of twin satellites having acceleration sensors, could detect global or regional microgravity changes and transform them into mass changes of water on surface and inside of the Earth. Numerous studies in terms of groundwater storage using GRACE sensor data were performed with several merits such that (1) there is no requirement of sensor data, (2) auxiliary data for quantification of groundwater can be entirely obtained from another satellite sensors, and (3) algorithms for processing measured data have continuously progressed from designated data management center. The limitations of GRACE for groundwater storage measurement could be defined as follows: (1) In an area with small scale, mass change quantification of groundwater might be inaccurate due to detection limit of the acceleration sensor, and (2) the results would be overestimated in case of combination between sensor and field survey data. InSAR can quantify the dynamic characteristics of aquifer by measuring vertical micro displacement, using linear proportional relation between groundwater head and vertical surface movement. However, InSAR data might now constrain their application to arid or semi-arid area whose land cover appear to be simple, and are hard to apply to the area with the anticipation of loss of coherence with surface. Development of GRACE and InSAR sensor data preprocessing algorithms optimized to topography, geology, and natural conditions of Korea should be prioritized to regionally quantify the mass change and dynamics of the groundwater resources of Korea.

• Journal of Hospice and Palliative Care
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• v.16 no.4
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• pp.205-215
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• 2013

Most terminally ill cancer patients experience various physical and psychological symptoms during their illness. In addition to pain, they commonly suffer from fatigue, anorexia-cachexia syndrome, nausea, vomiting and dyspnea. In this paper, I reviewed some of the common non-pain symptoms in terminally ill cancer patients, based on the National Comprehensive Cancer Network (NCCN) guidelines to better understand and treat cancer patients. Cancer-related fatigue (CRF) is a common symptom in terminally ill cancer patients. There are reversible causes of fatigue, which include anemia, sleep disturbance, malnutrition, pain, depression and anxiety, medical comorbidities, hyperthyroidism and hypogonadism. Energy conservation and education are recommended as central management for CRF. Corticosteroid and psychostimulants can be used as well. The anorexia and cachexia syndrome has reversible causes and should be managed. It includes stomatitis, constipation and uncontrolled severe symptoms such as pain or dyspnea, delirium, nausea/vomiting, depression and gastroparesis. To manage the syndrome, it is important to provide emotional support and inform the patient and family of the natural history of the disease. Megesteol acetate, dronabinol and corticosteroid can be helpful. Nausea and vomiting will occur by potentially reversible causes including drug consumption, uremia, infection, anxiety, constipation, gastric irritation and proximal gastrointestinal obstruction. Metoclopramide, haloperidol, olanzapine and ondansetron can be used to manage nausea and vomiting. Dyspnea is common even in terminally ill cancer patients without lung disease. Opioids are effective for symptomatic management of dyspnea. To improve the quality of life for terminally ill cancer patients, we should try to ameliorate these symptoms by paying more attention to patients and understanding of management principles.

• 보존과학연구
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• s.17
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• pp.161-182
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• 1996

In natural atmosphere, copper and copper alloy have been used to make buddha statues and ornaments of historic buildings since the abovementioned metals have corrosion resistance in some extent, and the patinaformed on the surface of the metals has provided the people aesthetic satisfaction with its beauty. But in atmosphere polluted by $SO_x$and $NO_x$, the patina layer does not work as a protective film, and it allows damages of the metal. Since 1992, Tokyo National Research Institute of Cultural Properties(TNRICP)has conducted studies on the influence of atmospheric pollution on metal cultural property held under open air. The Great Buddha Image which is located in Kamakura about 50km west from Tokyo, has been selected as one of the objects to study because it is made by copper alloy and it has stood exposed in the air for about a few hundreds years. Furthermore it is also the reason to study on it that there are many cultural properties in the surroundings of it. We have analysed the components and the structure of the corrosion products formed on the surface of the Buddha, have carried out exposure tests using the alloy samples which have simulated the components of the Great Image, and have observed climated and polluted air in order to discuss the relation between corrosion of metals in open air and conditions of the atmosphere. In this paper, the authors have described the components and the structure of the corrosion product formed on the surface of the Great Image by means of X-ray fluorescence spectroscopy and X-ray diffraction. The conclusions are as follows. (1) Sulfate patina composed mainly with brochantite were detected on the all sides of the Image and the amount of the patina is found more on the back of the Image facing to north. (2) Antlerite were detected on the back and a park of the left side facing to west, and formation of it was considered to have close relation with malignant atmosphere. (3) A big amount of chloride patina which mainly composed of atacamite were observed on the front facing to south. (4) Carbonate patina mainly composed of malachite were detected on the area where brochantite was often detected as well. It suggested that malachite had been transformed into brochantite by deteriorated atmosphere. (5) On the all sides of the Image, patina were observed together with copper oxides mainly composed of cuprous oxide. It showed that the surface layer of the Image consists of two layers : inner layer of oxide and outer layer of patina. (6) Corrosion products of lead which was a component of copperalloy were detected on the all sides : the main lead product found on the front was chlorophosphate whereas the one on the back was sulfate.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.05a
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• pp.91-93
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• 2003

A comprehensive numerical study is carried out to investigate for the understanding of the flow evolution and flame development in a supersonic combustor with normal injection of ncumally injecting hydrogen in airsupersonic flows. The formulation treats the complete conservation equations of mass, momentum, energy, and species concentration for a multi-component chemically reacting system. For the numerical simulation of supersonic combustion, multi-species Navier-Stokes equations and detailed chemistry of H2-Air is considered. It also accommodates a finite-rate chemical kinetics mechanism of hydrogen-air combustion GRI-Mech. 2.11[1], which consists of nine species and twenty-five reaction steps. Turbulence closure is achieved by means of a k-two-equation model (2). The governing equations are spatially discretized using a finite-volume approach, and temporally integrated by means of a second-order accurate implicit scheme (3-5).The supersonic combustor consists of a flat channel of 10 cm height and a fuel-injection slit of 0.1 cm width located at 10 cm downstream of the inlet. A cavity of 5 cm height and 20 cm width is installed at 15 cm downstream of the injection slit. A total of 936160 grids are used for the main-combustor flow passage, and 159161 grids for the cavity. The grids are clustered in the flow direction near the fuel injector and cavity, as well as in the vertical direction near the bottom wall. The no-slip and adiabatic conditions are assumed throughout the entire wall boundary. As a specific example, the inflow Mach number is assumed to be 3, and the temperature and pressure are 600 K and 0.1 MPa, respectively. Gaseous hydrogen at a temperature of 151.5 K is injected normal to the wall from a choked injector.A series of calculations were carried out by varying the fuel injection pressure from 0.5 to 1.5MPa. This amounts to changing the fuel mass flow rate or the overall equivalence ratio for different operating regimes. Figure 1 shows the instantaneous temperature fields in the supersonic combustor at four different conditions. The dark blue region represents the hot burned gases. At the fuel injection pressure of 0.5 MPa, the flame is stably anchored, but the flow field exhibits a high-amplitude oscillation. At the fuel injection pressure of 1.0 MPa, the Mach reflection occurs ahead of the injector. The interaction between the incoming air and the injection flow becomes much more complex, and the fuel/air mixing is strongly enhanced. The Mach reflection oscillates and results in a strong fluctuation in the combustor wall pressure. At the fuel injection pressure of 1.5MPa, the flow inside the combustor becomes nearly choked and the Mach reflection is displaced forward. The leading shock wave moves slowly toward the inlet, and eventually causes the combustor-upstart due to the thermal choking. The cavity appears to play a secondary role in driving the flow unsteadiness, in spite of its influence on the fuel/air mixing and flame evolution. Further investigation is necessary on this issue. The present study features detailed resolution of the flow and flame dynamics in the combustor, which was not typically available in most of the previous works. In particular, the oscillatory flow characteristics are captured at a scale sufficient to identify the underlying physical mechanisms. Much of the flow unsteadiness is not related to the cavity, but rather to the intrinsic unsteadiness in the flowfield, as also shown experimentally by Ben-Yakar et al. [6], The interactions between the unsteady flow and flame evolution may cause a large excursion of flow oscillation. The work appears to be the first of its kind in the numerical study of combustion oscillations in a supersonic combustor, although a similar phenomenon was previously reported experimentally. A more comprehensive discussion will be given in the final paper presented at the colloquium.

• Journal of the Korean association of regional geographers
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• v.4 no.2
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• pp.31-47
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• 1998

This paper deals with the historical geography of land-use and agriculture along the Lower Nam-River floodplains. The reclamation process of the river floodplains, the cultivation methods on the reclaimed lands, and the land-use patterns and processes are investigated. The Nam River, one of the major tributaries of the Nakdong River, flows through the boundary between Ham-An and Eu-Ryong Guns. Larger floodplains are located in Ham-An Gun. The floodplains of Ham-An Gun have been surveyed intensively in this study. In South Korea, the alluvial plains, mostly located along the river valleys, have been reclaimed to provide fertile agricultural lands. Those along the upper river valleys were reclaimed before those along the lower river valleys. The flood-plains of Han-An Gun were reclaimed to be the largest agricultural lands of the Gun. The natural levees along the Lower Nam-River Valley were identified before the reclamation processes but now hardly identified. Relatively larger floodplains are located along the tributary streams of the Nam River. Often there are low-lying back swamps between the natural levees and the hills/mountains that rise above the floodplains. The back swamps, called 'natural bog lands' in this region, have been reduced in size and in number through reclamation for the purpose of agricultural and industrial land-uses. Now about ten 'natural bog lands' are found in the Ham-An floodplains, and some of them are being reclaimed for the industrial land-use. This study suggests the emergent need of conservation for the remaining 'natural bog lands' in terms of ecology. Seven agricultural fields of large size, originated from the Nam-River floodplains, are identified in this study: Kun(큰들), Chung-Am(정암들), Chang-chi(장지들), Baek-San(백산들), Ha-Ki(하기들), Gu-Hae(구혜들), and Chang-Po(장포들) fields. The Kun field was reclaimed during the Japanese control and the Gu-Hae, in the 1950s. All of those except the above two fields were reclaimed after the mid-1960s. The Nam-River Dam in Chinju, completed in 1969, contributed the reclamation processes along the Lower Nam-River floodplains. The rice acreage of the region has been reduced slowly since 1970 but the rice production of the region has been relatively stable (Table 4). Rice culture had been the most important agriculture on the reclaimed lands for decades before the greenhouse vegetable cultivation became more important in the 1980s. Among the vegetables cultivated in the greenhouse, the watermelon is the dominantly leading one. Watermelons are usually harvested two or three times in a year though it is possible to harvest four times in one year. The rotation of watermelons and rice is common in the region. It is known the physical conditions of the Nam-River floodplains in Ham-An Gun is the most suitable for watermelon cultivation in South Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.1
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• pp.1-7
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• 2001

Total upland area for cultivating the vegetable crops in the Alpine soils of Northeastern South Korea has been extending its limit to meet the increasing demand of vegetable food in recent decades. About 70% of these alpine soils are located in over 7% of the slope and most of vegetable crops have been cultivated intensively without practicing the best management systems. Thus, soil erosion and continuous cropping system have degenerated the soil fertility and shown detrimental effects on water quality. We initiated an intensive and extensive investigation to characterize the fertility problems encountered in these uplands. Objectives of this paper were to characterize the fertility status in the Alpine soils cultivated with vegetable crops for many years and to provide the recommendations for adequate soil management measures including fertilization and erosion control. Soils in general have good drainage with textural classes of loam or sandy loam. Their topographical characteristics tended to lead them to shallow plow layers, and the steepness of the terrain created erosion hazard. Of the soils examined, about 11% of uplands over 30% gradient was found in need of an urgent reforestation. A high content of gravel and firm hardness of soil attributed to inhibit the utilization of farm machinery and plant-root development. The average soil pH 5.6 was slightly low relative to pH 5.70 of the national average. Organic matter content was high compared with 2.0% of national average, but decreased with the prolonged cultivation periods. Available $P_2O_5$ concentration was unusually high due to the consequence of over dose application with chemical and organic fertilizers. Exchangeable cations as Ca, Mg, and K were appeared to be decreased in these regions with prolonging the cultivation periods. There were no significant differences in cation exchange capacity (CEC) and electrical conductivity (EC) among locations. Heavy metal contents were mostly lower than the threshold of danger level designated by Soil Environment Conservation Law of South Korea. Results indicated that a proper countermeasure and the best management practice should be immediately implemented to conserve the top soil and fertility in the Alpine regions.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.21-28
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• 2009

Detailed information on soil characteristics is of great importance for the use and conservation of soil resources that are essential for human welfare and ecosystem sustainability. This paper introduces soil inventory of Korea focusing on national soil database establishment, information systems, use, and future direction for natural resources management. Different scales of soil maps surveyed and soil test data collected by RDA (Rural Development Administration) were computerized to construct digital soil maps and database. Soil chemical properties and heavy metal concentrations in agricultural soils including vulnerable agricultural soils were investigated regularly at fixed sampling points. Internet-based information systems for soil and agro-environmental resources were developed based on 'National Soil Survey Projects' for managing soil resources and for providing soil information to the public, and 'Agroenvironmental Change Monitoring Project' to monitor spatial and temporal changes of agricultural environment will be opened soon. Soils data has a great potential of further application in estimation of soil carbon storage, water capacity, and soil loss. Digital mapping of soil and environment using state-of-the-art and emerging technologies with a pedometrics concept will lead to future direction.

• Korean Journal of Heritage: History & Science
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• v.52 no.1
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• pp.4-21
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• 2019

In this paper, 23 Silla gold earrings from the sixth and seventhand centuries, excavated from the Yeongnam region, were analyzed. Based on the silver content of the gold plate, they were classified into three types. The classifications included type I(20-50wt%), type II(10-20wt%) and type III (less than 10wt%). In the analysis process, the composition and morphological differences were identified on the surface of the gold plate. In the case of type I and II earrings, it was observed that the fine holes were concentrated in a relatively higher part of the gold content. The causes of the difference in the surface composition of the gold plate were divided into four categories: 1) surface treatment, 2) thermal diffusivity in the manufacturing process, 3) differences in composition of alluvial gold, and 4) the refining method of gold. It is possible that depletion gilding was attempted to increase the gold content while intentionally removing the other metals from the surface of the gold alloy in the portion where the gold deposit is relatively concentrated on the surface of the gold plating. The highest copper content was detected in the earring with the highest gold content of the analyzed earrings, and it was assumed that thermal diffusion had occurred between the gold plate and the metal rod during the manufacturing process rather than intentional addition. Copper was detected only in the thin ring earring type, and copper was not detected in the thick ring earring type or pendant type. It also proves that this earring has a high degree of tightness at higher temperatures, as there was an invisible edge finish on other earrings and horizontal wrinkles on the gold plate surface. In terms of the material of the gold plate, we examined whether the silver content of the gold plate was natural gold or added by alloy through analyzing the alluvial gold collected in the region. As a result of the analysis, it was found that on average about 13wt% of silver is included. This suggests that type II is natural gold, type III is refined gold, and type I seems to have been alloyed with natural gold. Here, we investigated the refining method introduced in the ancient literature, both at home and abroad, about the possibility of alloying silver after the refining process of type III earrings and then making pure gold. It was found that from ancient refining methods, silver which had been present in the natural gold was removed by reacting and combining with silver chloride or silver sulfide, and long-term efforts and techniques were required to obtain pure gold through this method. Therefore, it was concluded that the possibility of adding a small amount of silver in order to increase strength after making pure gold through a refining process is low.

• Korean Journal of Heritage: History & Science
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• v.48 no.2
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• pp.120-141
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• 2015

This paper is a preliminary study of architectural characteristics of Jangdae (general's podium), which shows one of the technical changes in fortification of Joseon Dynasty. As a facility for commands of generals and training for officers and men, it was located inside a fortress. Although it is not certain when the first Jangdae was built, the number of them dramatically increased around 18th century. Since the top priority function of the Jangdae was the prospect, it was installed at the hilly spot with open architecture. In addition, the open structure of Eupseong fortress towers on the riverside banks could simultaneously offer the functions as viewing around and Jangdae. Since Jangdae was also a place for military drills and reviews of soldiers, a wide podium was positioned at the front to muster the soldiers. This feature was standardized in the space organization of Jangdae in Joseon, and a mere podium was installed unless the topographic restrictions allows enough space. On the other hand, as a place for a commander, the hierarchy of the Jangdae was revealed through a variety of architectural characteristics. The hierarchy was assigned to the commander's space through the altitude difference, and diverse ornaments were added to show a sense of class. The floor plan of the Jangdae building can be largely categorized into rectangle and square, and the typical sizes of the former are $5{\times}4$ Kans (traditional measuring unit between two columns) and $3{\times}2$ Kans. Out of these two types, buildings of $5{\times}4$ Kans were found in flat land and eupseong fortresses with large space, and the relatively smaller ones of $3{\times}2$ Kans in mountain fortresses. All buildings of square floor plan had $3{\times}3$ Kans style, and the center Kan was twice wider than the side Kan to make the central space wide. It seems that the purpose was to secure the interior space of the upper story because the center Kan accounts for the floor area of the upper story. Some Jangdae's had internal story to form overhead space. The multi-roofed tower style with eaves attached to the upper and lower story is found exclusively in Jangdae. The buildings shows the Onkanmulim style which extends Naejinju (inner column) of the lower story to be the Byeonju (outer column) of the upper story, and the log-framed floor in the upper floor was structured by inserting the Changbang (connecting beam) between the Naejinju's and joining the log frames. In addition, the towers in eupseong fortresses had log-framed floor in the upper floor by setting up the high Nuhaju (column underneath a roof) and joining Cheongbang to the upper part of the column while it cannot be regarded as multi-roofed because only the upper part has a roof.

• The Korean Journal of Archival Studies
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• no.3
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• pp.91-113
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• 2001

History always be re-interpreted as the time flows. 'The Sillok', Which was registered in Memory of World of UNESCO in 1997, is comprehensive documents of the Chosun Dynasty, which had been compiled after kings' death, The Sillok encompasses 473 years of the reign in their 848 volumes(1,893 chapters). It was a history itself and has been main source in studying Korean history. Due to the rise of studies on the Sillok, time has come to explore the nature of the Sillok and to criticize the text, which would be called 'The Sillok-Study'. In this context, this paper examined three concepts that categorize the nature of the Sillok as historical materials ;Is it book or record?; The Sillok in register system in pre-modern society; And the Sillok as the National Archives. Korean historians, including myself, haven't yet examined the question whether the Sillok is the Book or Record in terms of archival science. At first, I regarded it as history book, and with this presupposition, wrote several papers on the characteristics of the Sillok. However, I recognized that the Sillok are close to record rather that history book as I examined the definition of glossary of librarian study, OED (Oxford English Dictionary) and Encyclopedia of Britannica, etc. Definitely, the Sillok was neither compiled and published to be read and sold publicly, nor meant to the works of literature or scholarship. one may say that the court-historians wrote comments on the facts and therefore it was just scholarly work. However, because the court-historians produced their comments on their own businesses, the outcome of 'their scholarly works' were also records conceptually, as were daily court-journalists in Rome. Its publication also had a absolutely different meaning from that of modern society. It was a method to preserve the important national records and distributed each edition of them to plural repositories for its safety and security. How can we explain its book-like shape and the procedure of compilation after a kings' death. The answer is as follows ; In pre-modern society, it was a common record-keeping system in the world to register records materials in order to arrange the materials of different sizes and to store them conveniently. And the lack of scientific preservation or conservation skill also encouraged them to register original records. Actually, the court-historians who participated in the compiling process called themselves "registering officers". On the other hand, similar to social hierarchy, there was a hierarchical system of records, and the Sillok was placed at the top of this hierarchy. In conclusion, the Sillok was a kind of registered records in the middle ages and the supreme records in the records-world. In addition to this we can also conceptualize the Sillok as archives. Through the compiling process, the most important and valuable records were selected to be the parts of Sillok. This process corresponds to the modem records appraisal. In the next step, it was preserved in the Four Archives(史庫) which located at remote site as archives and only accessible by the descendents in the future, who might be the people of the next dynasty. And nobody could access or read the documents at that time except the authorized court-historians who were archivists of the Chosun Dynasty. From this perspective, I conclude that Sillok was the supreme confidential archives in the register system. I work for the Government Archives as a historian and archivist. Whenever I entered the exhibition hall of the Government Archives and Records Service(GARS) and saw the replica of the Archives of Taebeak Mountain built during Chosun period, I always asked to myself a question whether the Sillok can be a symbol of the archival tradition of Korea and the GARS. Now, I can say, 'Yes!' definitely.