• Title/Summary/Keyword: quality

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A Zoning Method for Forest Landscape Management by Visual Quality Assessment (시각적 질 평가에 의한 산림경관 관리구역 구획방법)

  • Lee, Gwan-Gyu;Park, Chan-Woo
    • Journal of Korean Society of Forest Science
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    • v.101 no.1
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    • pp.148-157
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    • 2012
  • Korea, with 63.7% of the land being forests, has unique characteristics of forest landscapes coming into view for most residential areas and roads. This study was undertaken with a purpose of supporting forest landscape management by partitioning the areas that landscape management is needed. Through analysing the degree of forest landscape management needs and the visual absorption capability for landscape changes, the zoning process and method for landscape management were conducted. In order to select the areas that are managed by priority for landscape, the degree of forest landscape management needs was quantitatively analyzed with the main scenic sites, travel frequencies, major forest landscape resources, and areas with demand for walking and automobile travel as the basis. The visual absorption capability that means the visual acceptance capability against physical landscape changes of the designated areas was analyzed in order to select the areas that are suitable for artificial landscape management. As a result, it became possible to express the degrees of forest landscape management needs in high, middle, and low sub-areas, and the visual absorption capability in high, middle, and low sub-areas, for each of the three zones in terms of spaces in the forest landscape management areas. For example, among the forest landscape transition zones, if the degree of forest landscape management needs is high and the visual absorption capability is high, then aggressive landscape management would be possible; this would also mean that this area could accept certain levels of physical landscape changes. By applying zoning methods like these, it was possible to attain a conclusive result that proper means of landscape design and management of the forest landscape resources and the surrounding areas could be provided.

A Study on Radiographical Conditions and Exposure Doses During Chest Radiography at Medical Facilities in Pusan (부산지역 의료기관의 흉부촬영 조건과 피폭선량에 관한 조사연구)

  • Jeon, Sung-Oh;Cho, Young-Ha
    • Journal of radiological science and technology
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    • v.20 no.2
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    • pp.49-55
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    • 1997
  • This study was carried out to investigate radiographical and operating conditions of X-ray units and exposure doses to patients during chest radiography, so that the results could provide basic data used for reducing the exposure dose and for providing the diagnostic information with better quality. The conditions and exposure doses of 100 X-ray units mainly used for chest radiography were examined and also 100 radiological technologists mainly handling those apparatus at 76 medical facilities in Pusan were surveyed using a questionnaire from October 1 to December 31 in 1995. The following results were obtained from the study : 1. It was found that most units were capable of taking a high tube voltage radiography by showing 67% of the units equipped with the maximum tube voltage of 150 kV, 94% with more than 500 mA for the rating capacity and 85% with the full wave type of a signal phase. 2. For actual chest radiographical conditions, however, 80% of the units were operated at $60{\sim}100\;kVp$ and only 14% at 100 kVp and over for the high tube voltage. 3. The average exposure time was less than 0.1 second, and eighty four percent of the units adapted the X-ray tube currents ranging from 200 to 300 mA, 80% the focus-film distances between 180 and 210 cm, and 63% the focus sizes of more than 2.0 mm. 4. Most units(98%) employed additional filters made of aluminum, 75% the thickness of filters less than 2.0 mm, and only 2 units the compound filters. 5. Ortho chromatic system was only adopted in 13% of screen film system for the units, and 73% used the grid ratio at 8 : 1 for the low tube voltage during chest radiography. 6. The average exposure dose of all X-ray units during chest radiography was $371\;{\mu}Sv$ with a difference of about 16 times between the minimum to the maximum, and $386\;{\mu}Sv$ both at hospitals and at health centers, followed by $380\;{\mu}Sv$ at general hospitals and $263\;{\mu}Sv$ at university hospitals without showing any statistically significant differences. In conclusion, since patients during chest radiography at medical facilities in Pusan exposed to high levels of radiation, it is recommended that appropriate added filters and grids necessary for the high tube voltage radiography and high-speed screen systems should be adopted and used as soon as possible in order to reduce exposure dose to the patients.

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The Trends and Application Prospects of Medical Information System on the Ubiquitous Environments (유비쿼터스 환경에서의 의료정보시스템 동향 및 응용의 전망)

  • Kim, Chang-Soo;Kim, Hwa-Gon
    • Journal of radiological science and technology
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    • v.28 no.3
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    • pp.193-201
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    • 2005
  • We are living in Ubiquitous society now. There is also trend of integration in medical field that is largely affected by outside environment. At this time, it is necessary to rightly understand the abstract, function, expected effect and management method of Integration Medical Information System(IMIS) to use this system effectively for solving many hospital information system problems and disadvantages. It is fact that large-sized hospitals are improving the quality of service for treatment of patients through building integrated Medical Information System. So it is necessary to change this individual system that is previously developed and used for treatment assistance, hospital affair or general management respectively to integrated management system, modify patient information or treatment information data to the data suitable for new system and build the integrated medical information system suitable for the hospital service with treatment data and integrated medical information. This paper suggested and designed abstract of integrated medical information system, the organization of system, the character of system and the plan and materialization of IMIS when building integrated medical information system. And the context of this paper is suggested trend of industry and solution of integration EMR, HIS, PACS. Therefore this paper is suggested development strategy, implemented integration medical information system.

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Characteristic of $^{18}F$-FDG Excretion According to Use Diuretics in $^{18}F$-FDG of PET/CT ($^{18}F$-FDG PET/CT 검사에서 이뇨제 사용여부에 따른 $^{18}F$-FDG 배설 특성)

  • Jang, Dong-Gun;Yang, Seoung-Oh;Lee, Sang-Ho;Bae, Jong-Lim;Kim, Jeong-Koo
    • Journal of radiological science and technology
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    • v.35 no.2
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    • pp.151-156
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    • 2012
  • $^{18}F$-fluorodeoxyglucose ($^{18}F$-FDG) causes a significant amount of radioactivity retention in kidneys and urinary tract and degrades image quality and diagnostic performance. Diuretics are used to perform tests and prevent the urinary tract retention of $^{18}F$-FDG. The purpose of the study is to investigate how the diuretics affect images and excretion rates of $^{18}F$-FDG. The study consists of a group using diuretics for patients with no primary tumors or transfer lesions in kidneys according to PET/CT images, a group using physiological saline and the control group injecting only $^{18}F$-FDG and SUVs are measured by configuring interested areas for each group. Also, SUVs are compared and evaluated depending on the lasix injection after basic inspection and injecting $^{18}F$-FDG for quantitative analysis. The study shows that images with decreased background radioactivity and increased urine excretion due to using diuretics. However, an opposite result that there is no change in the amount of radioactivity in urine appears. The study concludes that the diuretics may decrease background radioactivity in the images but may not affect the $^{18}F$-FDG excretion.

CdZnTe Detector for Computed Tomography based on Weighting Potential (가중 퍼텐셜에 기초한 CT용 CdZnTe 소자 설계)

  • Lim, Hyunjong;Park, Chansun;Kim, Jungsu;Kim, Jungmin;Choi, Jonghak;Kim, KiHyun
    • Journal of radiological science and technology
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    • v.39 no.1
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    • pp.35-42
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    • 2016
  • Room-temperature operating CdZnTe(CZT) material is an innovative radiation detector which could reduce the patient dose to one-tenth level of conventional CT (Computed Tomography) and mammography system. The pixel and pixel pitch in the imaging device determine the conversion efficiency of incident X-or gamma-ray and the cross-talk of signal, that is, image quality of detector system. The weighting potential is the virtual potential determined by the position and geometry of electrode. The weighting potential obtained by computer-based simulation in solving Poisson equation with proper boundaries condition. The pixel was optimized by considering the CIE (charge induced efficiency) and the signal cross-talk in CT detector system. The pixel pitch was 1-mm and the detector thickness was 2-mm in the simulation. The optimized pixel size and inter-pixel distance for maximizing the CIE and minimizing the signal cross-talk is about $750{\mu}m$ and $125{\mu}m$, respectively.

An Optimal Structure of a Novel Flat Panel Detector to Reduce Scatter Radiation for Clinical Usage: Performance Evaluation with Various Angle of Incident X-ray (산란선 제거를 위한 신개념 간접 평판형 검출기의 임상적용을 위한 최적 구조 : 입사 X선 각도에 따른 성능평가)

  • Yoon, Yongsu
    • Journal of radiological science and technology
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    • v.40 no.4
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    • pp.533-542
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    • 2017
  • In diagnostic radiology, the imaging system has been changed from film/screen to digital system. However, the method for removing scatter radiation such as anti-scatter grid has not kept pace with this change. Therefore, authors have devised the indirect flat panel detector (FPD) system with net-like lead in substrate layer which can remove the scattered radiation. In clinical context, there are many radiographic examinations with angulated incident X-ray. However, our proposed FPD has net-like lead foil so the vertical lead foil to the angulate incident X-ray would have bad effect on its performance. In this study, we identified the effect of vertical/horizontal lead foil component on the novel system's performance and improved the structure of novel system for clinical usage with angulated incident X-ray. Grid exposure factor and image contrast were calculated to investigate various structure of novel system using Monte Carlo simulation software when the incident X-ray was tilted ($0^{\circ}$, $15^{\circ}$, and $30^{\circ}$ from the detector plane). More photons were needed to obtain same image quality in the novel system with vertical lead foil only then the system with horizontal lead foil only. An optimal structure of novel system having different heights of its vertical and horizontal lead foil component showed improved performance compared with the novel system in a previous study. Therefore, the novel system will be useful in a clinical context with the angulated incident X-ray if the height and direction of lead foil in the substrate layer are optimized as the condition of conventional radiography.

An Estimation of the Composite Sea Surface Temperature using COMS and Polar Orbit Satellites Data in Northwest Pacific Ocean (천리안 위성과 극궤도 위성 자료를 이용한 북서태평양 해역의 합성 해수면온도 산출)

  • Kim, Tae-Myung;Chung, Sung-Rae;Chung, Chu-Yong;Baek, Seonkyun
    • Korean Journal of Remote Sensing
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    • v.33 no.3
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    • pp.275-285
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    • 2017
  • National Meteorological Satellite Center(NMSC) has produced Sea Surface Temperature (SST) using Communication, Ocean, and Meteorological Satellite(COMS) data since April 2011. In this study, we have developed a new regional COMS SST algorithm optimized within the North-West Pacific Ocean area based on the Multi-Channel SST(MCSST) method and made a composite SST using polar orbit satellites as well as the COMS data. In order to retrieve the optimized SST at Northwest Pacific, we carried out a colocation process of COMS and in-situ buoy data to make coefficients of the MCSST algorithm through the new cloud masking including contaminant pixels and quality control processes of buoy data. And then, we have estimated the composite SST through the optimal interpolation method developed by National Institute of Meteorological Science(NIMS). We used four satellites SST data including COMS, NOAA-18/19(National Oceanic and Atmospheric Administration-18/19), and GCOM-W1(Global Change Observation Mission-Water 1). As a result, the root mean square error ofthe composite SST for the period of July 2012 to June 2013 was $0.95^{\circ}C$ in comparison with in-situ buoy data.

Quality Consistence Analysis of Satellite-based Sea Ice Concentration Products (위성기반 해빙 농도 산출물들의 품질 일관성 분석)

  • Lee, Eunkyung;Seo, Minji;Lee, Kyeong-sang;Choi, Sungwon;Lee, Darae;Jin, Donghyun;Kwon, Chaeyoung;Kim, Honghee;Huh, Morang;Han, Kyung-Soo
    • Korean Journal of Remote Sensing
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    • v.33 no.3
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    • pp.333-338
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    • 2017
  • We compared sea ice concentration(SIC) and sea ice extent(SIE) using EUMETSAT Ocean and Sea Ice Satellite Application Facilities(OSI SAF) and NASA Team(NT) sea ice algorithm in the Arctic during 1980-2010 to investigate the difference between sea ice data applied different algorithms. SIC and SIE of the two data showed different consistency by season and by sea area. Seasonally, SIC of OSI SAF was 0.85 % overall, 0.48 % in spring, 0.97 % in summer, 1.38 % in autumn and 0.66 % in winter higher than NT SIC. By sea area, OSI SAF SIC was 2.7 %, SIE was $198,000km^2$ higher than NT in Arctic Ocean, but in Lincoln Sea, OSI SAF SIC was 2.3 %, SIE was $20,000km^2$ lower than NT.

Non-invasive Measurements of the Thickness of YBCO Thin Films by Using Microwave Resonators: Roles of the Uncertainty in the Calibration Film Thickness (마이크로파 공진기를 이용한 YBCO 박막 두께의 비파괴적 측정: 캘리브레이션 박막 두께의 불확도의 역할)

  • Kim, Myung-Su;Jung, Ho-Sang;Yang, Woo-Il;Lee, Sang-Young
    • Progress in Superconductivity
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    • v.14 no.1
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    • pp.45-51
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    • 2012
  • Microwave metrology for the thickness of metallic or superconductive films provides a new way to measure the film thickness in a non-invasive way by using microwave resonators, with the measurement accuracy affected by standard uncertainties in the resonator quality factor, temperature-dependent resonant frequency and the dimensions of the resonators. Here we study effects of the standard uncertainty in the thickness, $t_{cal}$, of a calibration $YBa_2Cu_3O_{7-{\delta}}$ (YBCO) film on the measured thicknesses, $t_{RF}$, by using a ~ 40 GHz microwave resonator. For the study, we used five YBCO films having the thicknesses of 70 - 360 nm, for which relative standard uncertainties in $t_{RF}$ due to that in $t_{cal}$ are obtained. The standard uncertainty in $t_{cal}$ was determined with the surface roughness of the film taken into account. It appeared that relative standard uncertainty in $t_{cal}$ significantly affects the $t_{RF}$ values, with the values of 1% (5%) in the former resulting in those of 1-2% (5-9%) for the latter at 10 K. Our results show that, for realizing relative standard uncertainties less than 5% in $t_{RF}$ for all the YBCO films, the surface roughness of the calibration films should be small enough to realize a relative standard uncertainty of less than 2.7% in $t_{cal}$.

A Study on Interdependence of Private Security and Techniques of CPTED (민간경비와 환경설계를 통한 범죄예방(CPTED) 기법의 상호의존성에 관한 연구)

  • Lee, Jung-Duk;Lim, You-Seok
    • Korean Security Journal
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    • no.29
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    • pp.223-249
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    • 2011
  • In modern society, citizens' quality of life aspects of safety and crime prevention activities are actively considering the incidence of crime prevention in advance. It also can be quite important elicit the interest of who community members through effective crime prevention strategies. For crime prevention policies and techniques over time as more scientific and advanced methods are made. Today, A typical crime prevention strategies is private security zones and Crime Prevention Through Environmental Design (CPTED) is a corresponding to the new strategy. CPTED is a diversification can be called a crime prevention approach that emphasizes the principle of natural surveillance, access control, territoriality, activity support, maintenance and management. The defensible space of the space area related to crime prevention setting the activities of private security and CPTED determine. Also, the reality of crime prevention and protection should be considered space. The emphasis on proactive prevention of crime in modern society for the prevention of crime how to approach differing perspectives and disparate aspects of private security and CPTED. Technical and professional areas that overlap to some extent in a homogeneous aspect. Ultimately, CPTED is a crime prevention through space and environmental approach for crime. In addition, Ultimate goal of convergence, crime prevention, with the same or higher is required to study for the area after looking for the characteristics and limitations of private security and CPTED.

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