• Journal of radiological science and technology
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• v.26 no.4
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• pp.39-46
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• 2003

Digital radiographic systems based on solid-state detectors, commonly referred to as flat-panel detectors, are gaining popularity in clinical practice. Large area, flat panel solid state detectors are being investigated for digital radiography. The purpose of this work was to evaluate the active matrix flat panel digital x-ray detectors in terms of their modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE). In this paper, development and evaluation of a selenium-based flat-panel digital x-ray detector are described. The prototype detector has a pixel pitch of $139\;{\mu}m$ and a total active imaging area of $14{\times}8.5\;inch^2$, giving a total 3.9 million pixels. This detector include a x-ray imaging layer of amorphous selenium as a photoconductor which is evaporated in vacuum state on a TFT flat panel, to make signals in proportion to incident x-ray. The film thickness was about $500\;{\mu}m$. To evaluate the imaging performance of the digital radiography(DR) system developed in our group, sensitivity, linearity, the modulation transfer function(MTF), noise power spectrum (NPS) and detective quantum efficiency(DQE) of detector was measured. The measured sensitivity was $4.16{\times}10^6\;ehp/pixel{\cdot}mR$ at the bias field of $10\;V/{\mu}m$ : The beam condition was 41.9\;KeV. Measured MTF at 2.5\;lp/mm was 52%, and the DQE at 1.5\;lp/mm was 75%. And the excellent linearity was showed where the coefficient of determination ($r^2$) is 0.9693.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.6
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• pp.334-342
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• 2016

Conventional eco-design has been implemented based only on the environmental aspects of a product. Key components of a product identified from the analysis of the environmental aspects have been the target for improvement in the conventional eco-design. The use of eco-design index (EDI) considering both the environmental and economic aspects, and utility value (UV) of a product can be envisaged as an alternative way of implementing and assessing the eco-design. The objective of this study was to propose the logic of the EDI and apply it to the components for performing printing function of the multi-function printer. The EDI was formulated by quantifying the UV, life cycle environmental impact (LCE) and life cycle cost (LCC) of the components of a product, here components of the printer. Of the eight components investigated, roller was identified as the best performing consumable in both the environmental and economic aspects. However, its UV was the lowest among the eight. The EDI of the roller was mere $4^{th}$ in ranking out of the eight. Transfer belt ranked $8^{th}$ and $5^{th}$ in the environmental and economic aspects, respectively, while $2^{nd}$ in the utility value with its EDI ranked $3^{rd}$. This indicates that not only the environmental aspects but also economic and utility value aspects should be considered when identifying the key components for improvement in the eco-design.

• Progress in Medical Physics
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• v.18 no.3
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• pp.144-148
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• 2007

Current digital radiography systems are rapidly glowing in clinical applications. The purpose of this study was to evaluate the characteristics of a mobile digital radiographic system. The performance of the mobile DR system was evaluated by measuring the modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE). Measurements were made on a LISTEM Mobix-1000 generator and a Teleoptic PRA Alpha-R4000 detector. Imaging characteristics were measured for these two systems using the IEC-61267 defined RQA5 (kVp: 74, additional filtration: 21 mmAl) radiographic condition. The MTF at 10% was measured as 2.4 cycles/mm and the DQE(0) values for radiation exposure 0.19, 0.5, and 1.3 mR were measured as 54%, 55%, and 76%, respectively. The NPS curves gradually decreased at high spatial frequencies. This high DQE at low frequencies, may be useful for low frequency information. The results suggested that mobile DR system could be integrated with emergency ambulance system in teleradiologic imaging applications.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.1 no.1
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• pp.45-55
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• 1998

Purpose: To make objective standards of small intestinal mucosal changes in cow's milk-sensitive enteropathy (CMSE) we analyzed histological changes of endoscopic duodenal mucosa biopsy specimens from normal children and patients of CMSE. Methods: We review the medical records of patients who had been admitted and diagnosed as CMSE by means of gastrofiberscopic duodenal mucosal biopsy following cow's milk challenge and withdrawal. Thirteen babies with CMSE, ranging from 14 days to 56 days of age, were studied. Five non-CMSE patients were used as control, ranging from 22 days to 72 days of age. The morphometric parameters under study were villous height, crypt zone depth, ratio of villous height to crypt zone depth, total mucosal thickness and length of surface epithelium by using H & E stained specimens under the drawing apparatus attached microscope. In addition, the numbers of lymphocytes in the epithelium and eosinophil cells in the lamina propria and epithelium were measured. Results: In the duodenal mucosal biopsy specimens in CMSE we found partial and subtotal villous atrophy with an increased number of interepithelial lymphocytes. The mean villous height($135{\pm}59\;{\mu}m$), ratio of villous height to crypt zone depth ($0.46{\pm}0.28$), total mucosal thickness ($499{\pm}56\;{\mu}m$), length of surface epithelium of small intestinal mucosa ($889{\pm}231\;{\mu}m$) in CMSE was significantly decreased compared with the control (p<0.05). The mean crypt zone depth ($311{\pm}65\;{\mu}m$) was significantly greater than the control ($188{\pm}24\;{\mu}m$)(p<0.05). Infiltration of interepithelial lymphocytes ($34.1{\pm}10.5$) were significantly greater than the control ($13.6{\pm}3.6$)(p<0.05). The number of eosinophil cells in both lamina propria and epithelium was no significant differences between groups (p>0.05). The small intestinal mucosa in treated CMSE showed much improved enteropathy of villous height, crypt zone depth, interepithelial lymphocytes compared with the control as well as untreated CMSE. Conclusion: Quantitation of mucosal dimensions confirmed the presence of CMSE. It seems to be a limitation in the capacity of crypt cells to compensate for the loss of villous epithelium in CMSE. Specimens obtained by gastrofiberscopic duodenal mucosal biopsy were suitable for morphometric diagnosis of CMSE. Improvement of CMSE also can be confirmed histologically after the therapy of protein hydrolysate.

• Investigative Magnetic Resonance Imaging
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• v.7 no.1
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• pp.31-38
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• 2003

Purpose : To analyze the serial changes of proton magnetic resonance (MR) spectra in the abscess and to determine the effect of the antibiotic treatment on the metabolite patterns. Materials and Methods : MR imaging and MR spectroscopy of an experimentally induced abscess were performed sequentially for four weeks at interval of one week in both the control group (n=5) and the antibiotic treatment group (n=5). On MR imaging, the shape and the size of the abscess were analyzed. On MR spectroscopy, the resonance peaks of metabolites were assigned on the basis of reported peaks in the literature. The metabolite ratios measured by using N-acetyl alanine as an external reference and by using lipid as an internal reference were compared in both the control and treatment g roups. Results : The abscesses were seen as cystic masses on MR imaging. On MR spectroscopy, the variable peaks of acetate, succinate and various amino acids, which are the metabolites of infection, were identified in the control and antibiotic treatment groups. The most frequent peak was that of acetate at 1.92ppm (70%). Both the peak ratios of acetate to lipid and acetate to external reference tended to decrease in the treatment group while the ratios did not change significantly in the control group. Conclusion : MR spectroscopy is useful not only for the diagnosis of abscess but also for monitoring the evolution of the abscess by using the acetate peak.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.118-130
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• 2024

Rehabilitation of mining areas can reduce damage to ecosystems. However, the effects of rehabilitation on ecosystem services (ESs) and its contribution to local communities are not well known. Thus, the aims of this study were to clearly identify the ES beneficiaries affected by mining activities, to determine how the beneficiaries profit from surrounding areas in cooperation with local stakeholders, and to manage the rehabilitation areas for the ESs that the beneficiaries want. This study chose 18 ESs (4 provisioning, 7 regulating, 5 cultural, and 2 habitat services) based on The Economics of Ecosystems and Biodiversity. A semi-structured questionnaire survey using an 11-point Likert scale was conducted among 87 community residents to investigate social awareness and identify key ESs. The survey results from two local communities showed high awareness and demands mainly on cultural (mental and physical health, aesthetic appreciation, and recreation) and regulating services (local climate and air quality, and moderation of extreme events). These services were related to the daily lives of residents in local communities, provided positive benefits, and potentially improved the residents' future livelihoods. However, the average questionnaire scores were limited to 6-7 points, indicating that the benefits to local communities were meager. The residents' awareness of provisioning service was negative, even if it provided goods and profit opportunities. This indicated a disconnection between local communities and provisioning services due to forest rehabilitation that did not consider local communities that traditionally relied on specific provisioning services before the onset of mining activities. Future forest rehabilitation in abandoned mine areas must consider the welfare of local communities for sustainable use of rehabilitated forests and enhancing ESs. In this study, only a qualitative evaluation based on frequency analyses was conducted. The quantification and valuation of key ESs are warranted in the future to promote ESs from forest rehabilitation in abandoned mine areas. The study results would be useful for developing site-specific ES promotion strategies for reforesting mine areas.

• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.717-726
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• 2009

Multivariate models were developed for the simultaneous spectrophotometric determination of copper (II), nickel (II) and zinc (II) in water with 1-(2-thiazolylazo)-2-naphthol as chromogenic reagent in the presence of Triton X-100. To overcome the drawback of spectral interferences, principal component regression (PCR) and partial least square (PLS) multivariate calibration approaches were applied. Performances were validated with several test sets, and their results were then compared. In general, no significant difference in analytical performance between PLS and PCR models. The root mean square error of prediction (RMSEP) using three components for $Cu^{2+}$, $Ni^{2+}$ and $Zn^{2+}$ were 0.018, 0.010, 0.011 ppm, respectively. Figures of merit such as sensitivity, analytical sensitivity, limit of detection (LOD) were also estimated. High reliability was achieved when the proposed procedure was applied to simultaneous determination of $Cu^{2+}$, $Ni^{2+}$ and $Zn^{2+}$ in synthetic mixture and tap water.

• Public Diplomacy: Theory and Practice
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• v.2 no.2
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• pp.1-26
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• 2022

Since the seminal publication of Joseph Nye's Soft Power, soft power became the central concept to public diplomacy. However, over-emphasis on soft power, which is still controversial, deterred academics from producing valuable knowledge that can be applied to practices in the field. Soft power is a cause and effect at the same time and thus it makes systematic analysis almost implausible because it is not only a tool for successful public diplomacy, but it is a result of successful diplomacy. This study aims at offering a theoretical framework linking soft power and public diplomacy by including various factors that may affect the outcomes of effective public diplomacy. This theoretical framework assessing the effectiveness of public diplomacy will make it possible to explore how and when new public diplomacy was adopted in a certain country and examine hard and soft power resources. The model also includes political system variables such as ideas and values, institutions, governance, leadership, and communication system, which are expected to influence public diplomacy effectiveness rather than soft power itself. The model yields the effectiveness of public diplomacy by assessing outcome and impact relative to input and output that are applicable to practices. The model is expected to enable both quantitative and qualitative studies generating possible propositions from the model with some preliminary outcomes of comparative case studies.

• Korean Journal of Soil Science and Fertilizer
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• v.31
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• pp.36-44
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• 1998

우리 나라에서 토양의 점토광물에 관한 최초의 연구는 1958년 김제지방의 답 토양에 관한 연구로 (Dewan, 1958)시작되었다. 1960년대 시작하여 1970년대 까지는 주로 토양점토광물의 동정이 이루어 졌다. 점토광물의 동정(同定)에 사용된 잔적토(殘積土)(Residual Soil)로는 화강암(花崗岩), 화강편마암(花崗片麻岩), 현무암(玄武岩), 석회암(石灰岩), 혈암(頁岩), 제(第)3기층(紀層), 홍적층(洪積層) 유래 토양과 토양종류별(土壤種類別)로는 과부식회색토(寡腐植灰色土), 염류토(鹽類土), 충적토(沖積土), 적황색토(赤黃色土), 화산회토(火山灰土), 퇴적토(堆積土), 갈색토(褐色土), 암쇄토(岩碎土), 저위생산답(低位生産畓)이였으며, 토양점토광물(土壤粘土鑛物)과 작물수량성(作物收量性) 관계에 관한 연구가 실시되었다. 1980년대에 들어와서는 토양중의 1차광물과 점토광물의 풍화에 대한 안정도와 1차광물의 동정이 행해졌으며, 이밖에 Kaolinite 입자의 전하에 관한 연구등 점토광물의 흡착과 활성 연구, 점토광물의 토양개량재로서의 흡착과 화학적 특성 변화 연구와 점토광물의 토양개량 시용효과에 관한 연구가 행해졌다. 1990년대에 들어와서는 토양 중의 1차광물과 점토광물의 정량에 대한 자료가 축척되었고, 토양의 풍화에 대한 안정성과 생성기작, Zeolite와 새로운 광물이 합성되었다. 또한 합성광물을 이용한 농업과 산업광물로의 응용성 환경 산업에서의 적용가능성에 대한 평가가 시도되었다. 토양의 점토광물의 조성에 관한 연구는 토양 모재를 중심으로 이루어졌는데, 화강암(花崗岩)에서는 Halloysite, 화강편마암(花崗片麻岩)에서는 Kaolinite, Metahalloysite, Illite, 산성암(酸性岩)에서는 Kaolinite, Venrmiculite와 Chlorite의 중간광물, 현무암(玄武岩)에서는 Illite, Kaolinite, Vermiculite, 석회암(石灰岩)에서는 Vermiculite-Chlorite 중간광물, Kaolinite와 Illite, 혈암(頁岩)에서는 Kaolinite, Halloysite, Illite 외 Vermiculite-Chlorite, 화산회토(火山灰土)에서는 Allophane이 주광물이었다. Soil Taxonomy와 토양광물과의 관계에서, 답 토양에서는 Entisols의 주점토광물은 2:1형과 1:1형 광물이지만 Inceptisols와 Alfisols에서는 Halloysite가 대부분이다. 밭 토양의 경우는 Alfisols의 주점토광물은 Vermiculite, Illite, Kaolinite이었고, Ultisols에서는 Vermiculite-Chlorite 중간광물이었다. 산림토양에서는 Inceptisols중에서 Andept는 Allophane, Alfisols에서는 2:1 광물이지만, Ultisols에서는 Halloysite이다. 모재별 조암 광물의 풍화와 점토광물의 생성과정에서 화강암(花崗岩)과 화강편마암(花崗片麻岩)의 장석류(長石類)는 kaoline광물로, 이 밖의 운모광물(雲母鑛物), 녹니석(綠泥石), 각섬석(角閃石), 휘석(輝石)으로부터 생성된 illite, chlorite, vermiculite는 풍화중간에 혼층단계(混層段階)를 거쳐서 kaoline 광물로 풍화된다. 석회암(石灰岩) 토양의 smectite가 Mg농도가 높은 토양용액으로부터 침전되어 생성되었거나 운모 또는 chlorite에서 유래된 vermiculite의 변성작용에 의해 생성되고, 혈암(頁岩)토양의 점토에 illite가 주로 풍화에 저항성이 큰 미립자의 함수백운모(含水白雲母)로부터 유래되며, 현무암(玄武岩) 중의 장석류(長石類)는 kaoline광물로, 휘석(輝石)은 chlorite${\rightarrow}$illite의 풍화과정을 거친다. Zeolite, 함불석 Bentonite, Bentonite 등 우량점토 광물이 분포과 광물조성, 이화학적 특성이 조사되었고, 토양의 물리적, 화학적 성질의 개선을 필요로 하는 토양의 개량을 위해서 Bentonite, Zeolite, Vermiculite 등의 토양 개량재(改良材)로서의 기초연구와 이들 개량재 시용효과에 관한 연구 등이 주로 논토양에서 수행되었다. 점토광물과 수량관계를 보면 Montmorillonite를 주점토광물로 함유된 답 토양의 수도수량이 1:1 광물을 주점토광물로 함유하고 있는 토양에서의 수도수량 보다 높았다. 토양광물에 관한 기초연구(基礎硏究)로서 양이온교환능과 포화이온의 영향, 입자의 전기화학적 성질, 흡탈착 성질, 표면적과 등전점, 해성점토에 대한 압밀점토(壓密粘土)의 변형율(變形率)의 추정 등이 주로 연구되었다. 부가가치가 낮거나 폐기되는 광물을 이용하여 토양개량재 혹은 흡착제를 형성하는 연구가 알카리 처리에 의한 Zeolite 합성에 집중되었다.

• The Korean Journal of Archival Studies
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• no.46
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• pp.95-152
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• 2015

"Archives of Everyday Life" refers to an organization or facility which collects, appraises, selects and preserves the document from the memory of individuals, groups, or a society through categorizing and classifying lives and cultures of ordinary people. The document includes materials such as diaries, autobiography, letters, and notes. It also covers any digital files or hypertext like posts from blogs and online communities, or photos uploaded on Social Network Services. Many research fields including the Records Management Studies has continuously claimed the necessity of collection and preservation of ordinary people's records on daily life produced every moment. Especially diary is a written record reflecting the facts experienced by an individual and his self-examination. Its originality, individuality and uniqueness are considered truly valuable as a document regardless of the era. Lately many diaries have been discovered and presented to the historical research communities, and diverse researchers in human and social studies have embarked more in-depth research on diaries, their authors, and social background of the time. Furthermore, researchers from linguistics, educational studies, and psychology analyze linguistic behaviors, status of cultural assimilation, and emotional or psychological changes of an author. In this study, we are conducting a metastudy from various research on diaries in order to reaffirm the value of "The 12th May Diaries Collection" as everyday life archives. "The 12th May Diaries Collection" consists of diaries produced and donated directly by citizens on the 12th May every year. It was only 2013 when Digital Archiving Institute in Univ. of Myungji organized the first "Annual call for the 12th May". Now more than 2,000 items were collected including hand writing diaries, digital documents, photos, audio and video files, etc. The age of participants also varies from children to senior citizens. In this study, quantitative analysis will be made on the diaries collected as well as more profound discoveries on the detailed contents of each item. It is not difficult to see stories about family and friends, school life, concerns over career path, daily life and feelings of citizens ranging all different generations, regions, and professions. Based on keyword and descriptors of each item, more comprehensive examination will be further made. Additionally this study will also provide suggestions to examine future research opportunities of these diaries for different fields such as linguistics, educational studies, historical studies or humanities considering diverse formats and contents of diaries. Finally this study will also discuss necessary tasks and challenges for "the 12th May Diaries Collection" to be continuously collected and preserved as Everyday Life Archives.