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Adoption and Efficacy of ISO 15189 in Medical Laboratories for Diagnostic and Research (메디컬시험기관에서 ISO 15189 도입의 필요성과 시행의 효용성)

  • Yang, Man-Gil;Lee, Won Ho;Jun, Jin Hyun
    • Korean Journal of Clinical Laboratory Science
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    • v.48 no.2
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    • pp.158-167
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    • 2016
  • The requirements for medical laboratories ISO 15189 is examined in organization and a quality management system, stressing the importance of evidence, document control, and control of records and clinical material. Medical services are provided from the areas of resource management, and pre-examination, examination and post-examination processes. The main goal of ISO 15189 accreditation is to improve the quality of laboratory services provided for patients and clinical users not only through compliance with consensually developed and harmonized requirements but also by adopting the philosophy of continual improvement using the Plan-Do-Check-Act cycle. Laboratory quality should be evaluated and improved in all steps of the testing process as the state-of-the art indicates that the pre- and post-analytical phases are more vulnerable to errors than the intra-analytical phase. The Korea Laboratory Accreditation Scheme (KOLAS), a national accreditation body, provides medical laboratory accreditations for appropriate approaches to evaluating the competence of a medical laboratory in providing effective services to its customers and clinical users. Adoption of ISO 15189 in 2010s as a government policy has been delayed, and only 5 laboratories have been accredited to date in Korea. The medical laboratories should seek the adoption of ISO 15189 with a positive attitude for quality improvement and strengthening of international competitiveness.

Half a cenury of the rural geography in Korea(1945-1995):review and prospect (촌락지리학 50년(1945-1995)의 회고와 전망)

  • ;Lee, Moon-Jong
    • Journal of the Korean Geographical Society
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    • v.31 no.2
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    • pp.213-254
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    • 1996
  • The Korean Geographical Society was founded in 1945, when Korea was liberated from the Japanese rule. And The Journal of the Korean Geography activated academic studies of geography by publishing research papers in it. Professor Kang, Dae-Hyun wrote the first two specialized papers of rural geography in 1966: " Flood Plain Settlements on the Han River" and "The Location and Form of the Dispersed Villages around Dae-Cwan-Ryung". The early studies of rural geography were not based on serious academic foundations, such as the adjustment of theoretical notions and a good grasp of subjects. After choosing subjects that came to hand without academic consideration. they simply enumerated generalized items of the results of the field work investigation such as the location the landscape and the process of formation of the settlements. In the 1970s and 1980s, however, rural settlement studies progressed remarkably in Korea. More than 80% of 318 dissertations, theses, or papers collected for this review were written in the late 1980s, and the subjects and methodology became diversified. As may be expected, recent studies are found very systematic and problem-solving in the various fields - contexual understanding spatial structure, the development of clan villages according to the socialization process, the effects of rural-out migration on the change of villages etc. Such a trend can be understood as a reaction to the circumstances under which, as the Western society already experienced, rural villages become washed out by the waves of industralization and urbanization and hardly continue to exist. In this paper, geographical studies of rural settlement which have been carried out in Korea last fifty years will be reviewed under the four headings on the studies related to a) farming villages; b) fishing villages; c) mountain villages: and d) special function villages. Studies of farming villages and related ones are very diverse. The results of the studies carried out last fifty years can be classified into sixteen subjects. Just as, in the West, studies of rural settlement have been mainly concerned with farming villages since rural geography came into being, so, in Korea, they have been centred on farming villages. It is a natural result considering the history of human life. Even in Korea, however the rural settlement is no more an isolated life space which keeps unique traditions of old life style, but it begins to form a dynamic life space connected to big cities by heavy traffic. Because the modern farming villages of Korea have an undetachable connection with the cities, special methodology to solve new problems has been posed in the studies of rural settlement. Many scholars have produced a lot of studies of farming villages, and three of them are prominent: Oh. Hong-Seok, Choi, Ki-Yeop, and Lee, Moon-Jong. Oh, Hong-Seok is a versatile and hard-working scholar who has published more papers than anyone else in the various fields of rural geography such as farming villages, fishing villages, mountain villages, and reclamation villages. And he has expanded his concerns to environment issues in recent years. Choi, Ki-Yeop has maintained that the prototype of Korean rural villages is clan villages continuing to write a series of good papers in which he pursues their regionalizion in the process of socialization. Lee, Moon-Jong divides the spatial organization of side settlement, sahachon (settlement near the temple), religion settlement, orchard settlement, settlement near the foreign military camp, displaced people's settlement. Chung Gam Lok settlement, etc. Though The Korean Geographical Society has half a century's history, academic activties in the field of rural settlement have been performed no more than thirty years. We cannot help saying that it is admirable that in such a rather short time we have five academical schools of the rural geography in Korea. geography in Korea.

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Analysis Corrosion Products Formed on the Great Buddha Image of Kotokuin Temple in Kamakura (고덕원 국보 동조아미타여래좌상의 표면에 생성한 부식생성물의 해석)

  • Matsuda Shiro;Aoki Shigeo;Kang, Dai-il
    • 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.

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Relationship between iron deficiency anemia and febrile convulsion in infants (영아에서 철결핍 빈혈과 열성경련과의 상관관계)

  • Jun, Youn Soo;Bang, Ho Il;Yu, Seung Taek;Shin, Sae Ron;Choi, Du Young
    • Clinical and Experimental Pediatrics
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    • v.53 no.3
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    • pp.392-396
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    • 2010
  • Purpose : The association between iron deficiency anemia and febrile convulsion in infants has been examined in several studies with conflicting results. Therefore, the authors aimed to evaluate the precise relationship involved. Methods : In this case-control study, the authors assessed 100 children with a diagnosis of febrile convulsion, aged between 9 months and 2 years, during January 2007 to July 2009. The control group consisted of 100 febrile children without convulsion; controls were closely matched to the cases by age, gender, and underlying disease. Results : The mean ages of the febrile convulsion and control group were $16.3{\pm}7.4$ and $15.8{\pm}6.1$ months, respectively, and the two groups had no differences in clinical features. Iron deficiency anemia (Hb <10.5 gm/dL) was more frequent in the febrile convulsion group than in the control group, although there was no statistical significance. Unexpectably, the RDW (red blood cell distribution width) was significantly lower and the MCNC (mean corpuscular hemoglobin concentration) was significantly higher among seizure cases than among the controls (P <0.05). There is no statistical difference between simple and complex febrile groups in the clinical and laboratory profiles. On multiple logistic regression analysis, iron deficiency anemia was more frequent, but the RDW was lower, among the cases with febrile convulsion, compared with the controls. Conclusions : Our study suggests that the iron deficiency anemia is associated with febrile convulsion, and screening for iron deficiency anemia should be considered in children with febrile convulsions.

의료인의 호스피스가정간호에 대한 지식과 태도 조사연구

  • Kim, Ok-Gyeom
    • Korean Journal of Hospice Care
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    • v.2 no.2
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    • pp.28-48
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    • 2002
  • The advances of medical technologies have not only prolonged human life span, but also extended suffering period for the patients with incurable medical diseases. Hospice movement was developed to help these patients keep dignity and lives peaceful at the end of their life. Since many patients prefer to spend the last moment of life at home with their family, hospice home care has become very popular worldwide. The purpose of this study for a promotion and development of hospice home care in Korea, and features basic research on medical profession's knowledge and attitudes to hospice home care. This study which was used for the research questionnaires developed by the researcher that were answered by 100 physicians and 127 nurses in a general hospital. Data were collected from April 22, 2002 to May 10, 2002. The SPSS was used to make a comparative analysis of the frequency, percentile, ANOVA, and x2-test. The results of the study were as follows; 1.The medical profession showed high level of knowledge of the definition and philosophy of hospice. However, the physician group of the examinees showed insufficient knowledge of the fact that hospice care includes bereavement care, while the nurse group's response to the same question showed a significant difference(x2=10.752, p=.001). 2.For whom the hospice home care is provided, 95.6% of the respondents showed very high level of knowledge as answering that the incurable terminal illness patients and their families are the beneficiaries of hospice care. The respondents counted nurses, volunteers, pastors, physicians and social workers, consecutively, as hospice care providers. More nurse were positive toward pastors than physicians in regarding as a hospice care provider by a significant difference(x2=11.634, p=.001). 3.For when to referral hospice home care to the patients, only 34.2% answered that patients with less than 6 months of survival time are advised to receive hospice care, reflecting very low level of knowledge. 23.0% of the physicians and 48.0% of the nurses answered that hospice care should be provided when death is imminent, making a significant difference between the two groups(x2=6.413, p=.000). 4.To promote hospice activities, 87.2% pointed out that it is crucial to make general people, including those engaging in the medical field, more aware of hospice. 79.7% answered that a national hospice management should be developed, marking a significant difference between the physician group and nurse group(x2=10.485, p=.001). 5.Advantages of hospice home care are 87.2% responded that patients can have better rest at home receiving hospice home care. Economical merit was brought forward as one of the advantages also, where there was a significant difference between the physicians group and nurse group(x2=7.009, p=.008). 6.The medical professions' attitude to hospice home care are 92.8% of the physicians answered that they would advise incurable terminally ill patients to be discharged from hospital, with 44.3% of them advising the patients to receive hospice home care after leaving the hospital. From the nurses' point of view, 20.9% of the terminally ill patients are being referred to hospice home care after discharge, which makes a significant difference from the physicians' response(x2=19.121, p=.001). 7. 30.6% of physicians have referred terminally ill patients to hospice home care, 75.9% of whom were satisfied with their decision. Those physicians who have never referred their patients to hospice home care either did not know how to do it(66.7%) or were afraid of losing trust by giving the patients an impression of giving up(27.3%). 94.9% of the physicians responded that they would refer their last stage patients to a doctor who is involving palliative care. 8.Only 36.2% of nurses have suggested to physicians that refer the terminally ill patients discharged from the hospital to hospice home care. Once suggested, 95.8% of the physicians have accepted the suggestion. Nurses were reluctant to suggest hospice home care to the physicians, as 48.8% of the nurses said they did not want to. From the result of this study the following conclusion can be drawn, the medical profession's awareness of general hospice care has been increased greatly compared to the results of the previously performed studies. However, this study result also shows that their knowledge of hospice home care is not good enough yet. There is a need for high recommended that medical education institute and develop regular courses on various types of hospice care. Medical field training courses for physicians and nurses will be very helpful as well. It is also important to train hospice experts such as palliative physicians and develop a national hospice management urgently in order to improve the hospice care in Korea.

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Study of Rat Mammary Epithelial Stem Cells In Vivo and In Vitro (생체 및 시험관에서 유선 상피 모세포의 분리와 동정)

  • Nam Deuk Kim;Kee-Joo Paik
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.3
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    • pp.470-486
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    • 1995
  • Mammary epithelial cells contain a subpopulation of cells with a large proliferativ potential which are responsible for the maintenance of glandular cellularity and are the progenitor cells of mammary cancer. These clonogens give rise to multicellular clonal alveolar or ductal units(AU or DU) on transplantation and hormonal stimulation. To isolate putative mammary clonogens, enzymatically monodispersed rat mammary epithelial cells from organoid cultures and from intact glands are sorted by flow cytometry according to their affinity for FITC labeled peanut lectin(PNA) and PE labeled anti-Thy-1.1 antibody(Thy-1.1) into four subpopulations : cells negative to both PNA and Thy-1.1(B-), PNA+cells, Thy-1.1+cells, and cells positive to both reagents(B+). The in vivo transplantation assays indicate that the clonogenic fractions of PNA+cells from out-growths of organoids in primary cultures for three days in complete hormone medium(CHM) are significantly higher than those of cells from other subpopulations derived from cultrues or from intact glands. Extracellular matrix(ECM) is a complex of several proteins that regulated cell function ; its role in cell growth and differentiation and tissue-specific gene expression. It can act as a positive as well as a negative regulator of cellular differentiation depending on the cell type and the genes studied. Regulation by ECM is closely interrelated with the action of other regulators of cellular function, such as growth factors and hormones. Matrigel supports the growth and development of several different multicellular colonies from mammary organoids and from monodispersed epithelial cells in culture. Several types of colonies are observed including stellate colonies, duct-like structures, two- and three-dimensional web structures, squamous organoids, and lobulo-duct colonies. Organoids have the greatest proliferative potential and formation of multi-cellular structures. Phase contrast micrographs demonstrate extensive intracellular lipid accumulation within the web structures and some of duct-like colonies. At the immunocytochemical and electron micrograph level, casein proteins are predominantly localized near the apical surface of the cells or in the lumen of duct-like or lobulo-duct colonies. Squamous colonies are comprised of several layers of squamous epithelium surrounding keratin pearls as is typical fo squamous metaplasia(SM). All-trans retinoic acid(RA) inhibits the growth of SM. The frequency of lobulo-ductal colony formation increased with the augmentation of RA concentration in these culture conditions. The current study models could provide powerful tools not only for understanding cell growth and differentiation of epithelial cells, but also for the isolation and characterization of mammary clonogenic stem cells.

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Management Guideline and Avifauca of Odaesan area in Odaesan National Park (오대산 국립공원 오대산 지역의 야생조류상 및 관리 방안)

  • 이우신;박찬열;조기현
    • Korean Journal of Environment and Ecology
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    • v.10 no.1
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    • pp.1-13
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    • 1996
  • This study was conducted to investigate the avifauna and to suggest the management discipline for the protection of bird community in Odaesan National Park. Field survey was carried over 2 main trails by line transect method from mid June to early December in 1996. The 1st section included the area from Woljongas to Sangwonsa 7km distance. The 2nd section survey started from Sangwonsa via Bukdaesa and the summit of Odaesan to Sangwonsa 9.8 km distance. The study results were as follows ; The observed birds belonged to 9 orders 22families 52species, they also had Black Woodpecker(Dryocopus martius)designated as natural monument No. 242, Chinese Sparrow Hawk(Accipiter soloensis) and Kestrel(Falco tinnunculus) as natural munumet No. 323, Scops Owl(Out scops)and Korean Wood Owl(Strix aluco) as No. 324. These birds also were classified into 25 species for residents, 16 species for summer visitors, 8 species for passage migrants, 3 species for winter visitors, respectionely. The 2nd section showed a high species richness and individuals in every season, however, had a difference in species composition with 1st section. Nesting guild of breeding bird community used highly in order of bush, hole, and canopy as a nest resources. It is suggested that high bush-nesting guild had a deep relationship with bush layer located in the ecotone of 1st section and that located in the high elevated zone in 2nd section. Hole-nesting guild such as Black Woodpecker(Dryocopus martius), Gray-headed Woodpecker(Picus canus) and Great Spotted Woodpecker(Dendrocopos major) were surveyed only in 2nd section, so it could be attribute to the small fragmentation and the growing of high diameter at breast height(D.B.H) tree in 2nd section. It is urgent that the management of camping ground and people for the conservation of brook in 1nd section, trail protection for the prevention from trail enlargement in 2nd section for the bird protection. Artificial food in snowy winter will provide the good breeding condition with the residents and migrants. And, the endeavor to lessen the habitat fragmentation will be beneficial to the birds who have a large home range such as Black Woodpecker(Dryocopus martius) and Korean Wood Owl(Strix aluco). For the control of Domestic Dove(Columba livia) populations, it could be recommended that the elimination of their nesting resources by net.

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Hardware Approach to Fuzzy Inference―ASIC and RISC―

  • Watanabe, Hiroyuki
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.975-976
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    • 1993
  • This talk presents the overview of the author's research and development activities on fuzzy inference hardware. We involved it with two distinct approaches. The first approach is to use application specific integrated circuits (ASIC) technology. The fuzzy inference method is directly implemented in silicon. The second approach, which is in its preliminary stage, is to use more conventional microprocessor architecture. Here, we use a quantitative technique used by designer of reduced instruction set computer (RISC) to modify an architecture of a microprocessor. In the ASIC approach, we implemented the most widely used fuzzy inference mechanism directly on silicon. The mechanism is beaded on a max-min compositional rule of inference, and Mandami's method of fuzzy implication. The two VLSI fuzzy inference chips are designed, fabricated, and fully tested. Both used a full-custom CMOS technology. The second and more claborate chip was designed at the University of North Carolina(U C) in cooperation with MCNC. Both VLSI chips had muliple datapaths for rule digital fuzzy inference chips had multiple datapaths for rule evaluation, and they executed multiple fuzzy if-then rules in parallel. The AT & T chip is the first digital fuzzy inference chip in the world. It ran with a 20 MHz clock cycle and achieved an approximately 80.000 Fuzzy Logical inferences Per Second (FLIPS). It stored and executed 16 fuzzy if-then rules. Since it was designed as a proof of concept prototype chip, it had minimal amount of peripheral logic for system integration. UNC/MCNC chip consists of 688,131 transistors of which 476,160 are used for RAM memory. It ran with a 10 MHz clock cycle. The chip has a 3-staged pipeline and initiates a computation of new inference every 64 cycle. This chip achieved an approximately 160,000 FLIPS. The new architecture have the following important improvements from the AT & T chip: Programmable rule set memory (RAM). On-chip fuzzification operation by a table lookup method. On-chip defuzzification operation by a centroid method. Reconfigurable architecture for processing two rule formats. RAM/datapath redundancy for higher yield It can store and execute 51 if-then rule of the following format: IF A and B and C and D Then Do E, and Then Do F. With this format, the chip takes four inputs and produces two outputs. By software reconfiguration, it can store and execute 102 if-then rules of the following simpler format using the same datapath: IF A and B Then Do E. With this format the chip takes two inputs and produces one outputs. We have built two VME-bus board systems based on this chip for Oak Ridge National Laboratory (ORNL). The board is now installed in a robot at ORNL. Researchers uses this board for experiment in autonomous robot navigation. The Fuzzy Logic system board places the Fuzzy chip into a VMEbus environment. High level C language functions hide the operational details of the board from the applications programme . The programmer treats rule memories and fuzzification function memories as local structures passed as parameters to the C functions. ASIC fuzzy inference hardware is extremely fast, but they are limited in generality. Many aspects of the design are limited or fixed. We have proposed to designing a are limited or fixed. We have proposed to designing a fuzzy information processor as an application specific processor using a quantitative approach. The quantitative approach was developed by RISC designers. In effect, we are interested in evaluating the effectiveness of a specialized RISC processor for fuzzy information processing. As the first step, we measured the possible speed-up of a fuzzy inference program based on if-then rules by an introduction of specialized instructions, i.e., min and max instructions. The minimum and maximum operations are heavily used in fuzzy logic applications as fuzzy intersection and union. We performed measurements using a MIPS R3000 as a base micropro essor. The initial result is encouraging. We can achieve as high as a 2.5 increase in inference speed if the R3000 had min and max instructions. Also, they are useful for speeding up other fuzzy operations such as bounded product and bounded sum. The embedded processor's main task is to control some device or process. It usually runs a single or a embedded processer to create an embedded processor for fuzzy control is very effective. Table I shows the measured speed of the inference by a MIPS R3000 microprocessor, a fictitious MIPS R3000 microprocessor with min and max instructions, and a UNC/MCNC ASIC fuzzy inference chip. The software that used on microprocessors is a simulator of the ASIC chip. The first row is the computation time in seconds of 6000 inferences using 51 rules where each fuzzy set is represented by an array of 64 elements. The second row is the time required to perform a single inference. The last row is the fuzzy logical inferences per second (FLIPS) measured for ach device. There is a large gap in run time between the ASIC and software approaches even if we resort to a specialized fuzzy microprocessor. As for design time and cost, these two approaches represent two extremes. An ASIC approach is extremely expensive. It is, therefore, an important research topic to design a specialized computing architecture for fuzzy applications that falls between these two extremes both in run time and design time/cost. TABLEI INFERENCE TIME BY 51 RULES {{{{Time }}{{MIPS R3000 }}{{ASIC }}{{Regular }}{{With min/mix }}{{6000 inference 1 inference FLIPS }}{{125s 20.8ms 48 }}{{49s 8.2ms 122 }}{{0.0038s 6.4㎲ 156,250 }} }}

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Processing and Quality Control of Flux Data at Gwangneung Forest (광릉 산림의 플럭스 자료 처리와 품질 관리)

  • Lim, Hee-Jeong;Lee, Young-Hee
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.10 no.3
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    • pp.82-93
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    • 2008
  • In order to ensure a standardized data analysis of the eddy covariance measurements, Hong and Kim's quality control program has been updated and used to process eddy covariance data measured at two levels on the main flux tower at Gwangneung site from January to May in 2005. The updated program was allowed to remove outliers automatically for $CO_2$ and latent heat fluxes. The flag system consists of four quality groups(G, D, B and M). During the study period, the missing data were about 25% of the total records. About 60% of the good quality data were obtained after the quality control. The number of record in G group was larger at 40m than at 20m. It is due that the level of 20m was within the roughness sublayer where the presence of the canopy influences directly on the character of the turbulence. About 60% of the bad data were due to low wind speed. Energy balance closure at this site was about 40% during the study period. Large imbalance is attributed partly to the combined effects of the neglected heat storage terms, inaccuracy of ground heat flux and advection due to local wind system near the surface. The analysis of wind direction indicates that the frequent occurrence of positive momentum flux was closely associated with mountain valley wind system at this site. The negative $CO_2$ flux at night was examined in terms of averaging time. The results show that when averaging time is larger than 10min, the magnitude of calculated $CO_2$ fluxes increases rapidly, suggesting that the 30min $CO_2$ flux is influenced severely by the mesoscale motion or nonstationarity. A proper choice of averaging time needs to be considered to get accurate turbulent fluxes during nighttime.

Characterization of Iron Oxides in Soils of Cheju Island by Mössbauer Spectroscopy and Chemical Techniques (Mössbauer 분광법(分光法)과 선택적(選擇的) 추출방법(抽出方法)에 의한 제주도(濟州道) 토양(土壤)에서의 산화철(酸化鐵)의 특성(特性) 구명(究明))

  • Kang, Dong-Woo;Kim, Doo-Chul;Ko, Jeong-Dae;Hong, Sung-Rak;Song, Kwan-Cheol
    • Korean Journal of Soil Science and Fertilizer
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    • v.30 no.1
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    • pp.3-15
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    • 1997
  • Iron oxide compounds in 8 selected Cheju Island soil samples have been analized by X-ray fluorescence spectrometer(XRF), X-ray diffractometry(XRD), selected chemical techniques, and $M{\ddot{o}}ssbauer$ spectroscopy. The result of this analysis by XRF shows that the rate of quantity of $Fe_2O_3$ in 8 soil samples was from 8.03wt.%(Daejeong paddy soil) to 18.21wt.%(Songag soils). Songag, Heugag and Gueom soils were detected to have lower peaks of intensity of hematite by XRD. In addition, these soils were not detected to have hematite and goethite peaks. Ferrihydrite, which is a short-range-order mineral commonly present in volcanic ash soil, was not detected by XRD due to low concentration and/or poor cristallinity. Ferrihydrite contents estimated from Feo values were 8.8~35.2g/kg for volcanic ash soils and 0.85g/kg for the Daejeong soil. Most of the soil samples represented by the paramagnetic $Fe^{3+}$ doublet obtained from $M{\ddot{o}}ssbauer$ spectra at room temperature and 18K were considered to arise from the presence of ferrihydrite, superparamagnetic goethite, and silicate minerals. Also the paramagnetic $Fe^{2+}$ doublets are attributable to primary minerals such as olivine, illite, chlorite, augite, biotite, and hornblende. Goethite and hematite were identified as the dominant crystalline iron oxides in these soils from $M{\ddot{o}}ssbauer$ spectra obtained at room temperature and 18K. All the soil samples exhibited strong superparamagnetic relaxation. Collapse of the $M{\ddot{o}}ssbauer$ magnetic hyperfine splitting at room temperature was due to the small size(${\sim}180{\AA}$) of the oxide particles and/or Al-subsituted goethite.

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