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Trend in Research and Application of Hard Carbon-based Thin Films (탄소계 경질 박막의 연구 및 산업 적용 동향)

  • Lee, Gyeong-Hwang;Park, Jong-Won;Yang, Ji-Hun;Jeong, Jae-In
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.05a
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    • pp.111-112
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    • 2009
  • Diamond-like carbon (DLC) is a convenient term to indicate the compositions of the various forms of amorphous carbon (a-C), tetrahedral amorphous carbon (ta-C), hydrogenated amorphous carbon and tetrahedral amorphous carbon (a-C:H and ta-C:H). The a-C film with disordered graphitic ordering, such as soot, chars, glassy carbon, and evaporated a-C, is shown in the lower left hand corner. If the fraction of sp3 bonding reaches a high degree, such an a-C is denoted as tetrahedral amorphous carbon (ta-C), in order to distinguish it from sp2 a-C [2]. Two hydrocarbon polymers, that is, polyethylene (CH2)n and polyacetylene (CH)n, define the limits of the triangle in the right hand corner beyond which interconnecting C-C networks do not form, and only strait-chain molecules are formed. The DLC films, i.e. a-C, ta-C, a-C:H and ta-C:H, have some extreme properties similar to diamond, such as hardness, elastic modulus and chemical inertness. These films are great advantages for many applications. One of the most important applications of the carbon-based films is the coating for magnetic hard disk recording. The second successful application is wear protective and antireflective films for IR windows. The third application is wear protection of bearings and sliding friction parts. The fourth is precision gages for the automotive industry. Recently, exciting ongoing study [1] tries to deposit a carbon-based protective film on engine parts (e.g. engine cylinders and pistons) taking into account not only low friction and wear, but also self lubricating properties. Reduction of the oil consumption is expected. Currently, for an additional application field, the carbon-based films are extensively studied as excellent candidates for biocompatible films on biomedical implants. The carbon-based films consist of carbon, hydrogen and nitrogen, which are biologically harmless as well as the main elements of human body. Some in vitro and limited in vivo studies on the biological effects of carbon-based films have been studied [$2{\sim}5$].The carbon-based films have great potentials in many fields. However, a few technological issues for carbon-based film are still needed to be studied to improve the applicability. Aisenberg and Chabot [3] firstly prepared an amorphous carbon film on substrates remained at room temperature using a beam of carbon ions produced using argon plasma. Spencer et al. [4] had subsequently developed this field. Many deposition techniques for DLC films have been developed to increase the fraction of sp3 bonding in the films. The a-C films have been prepared by a variety of deposition methods such as ion plating, DC or RF sputtering, RF or DC plasma enhanced chemical vapor deposition (PECVD), electron cyclotron resonance chemical vapor deposition (ECR-CVD), ion implantation, ablation, pulsed laser deposition and cathodic arc deposition, from a variety of carbon target or gaseous sources materials [5]. Sputtering is the most common deposition method for a-C film. Deposited films by these plasma methods, such as plasma enhanced chemical vapor deposition (PECVD) [6], are ranged into the interior of the triangle. Application fields of DLC films investigated from papers. Many papers purposed to apply for tribology due to the carbon-based films of low friction and wear resistance. Figure 1 shows the percentage of DLC research interest for application field. The biggest portion is tribology field. It is occupied 57%. Second, biomedical field hold 14%. Nowadays, biomedical field is took notice in many countries and significantly increased the research papers. DLC films actually applied to many industries in 2005 as shown figure 2. The most applied fields are mold and machinery industries. It took over 50%. The automobile industry is more and more increase application parts. In the near future, automobile industry is expected a big market for DLC coating. Figure 1 Research interests of carbon-based filmsFigure 2 Demand ratio of DLC coating for industry in 2005. In this presentation, I will introduce a trend of carbon-based coating research and applications.

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A Design and Implementation of Multimedia Retrieval System based on MAF(Multimedia Application File Format) (MAF(Multimedia Application File Format) 기반 멀티미디어 검색 시스템의 설계 및 구현)

  • Gang Young-Mo;Park Joo-Hyoun;Bang Hyung-Gin;Nang Jong-Ho;Kim Hyung-Chul
    • Journal of KIISE:Computer Systems and Theory
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    • v.33 no.9
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    • pp.574-584
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    • 2006
  • Recently, ISO/IEC 23000 (also known as 'MPEG-A') has proposed a new file format called 'MAF(Multimedia Application File Format)[1]' which provides a capability of integrating/storing the widely-used compression standards for audio and video and the metadata in MPEG-7 form into a single file format. However, it is still very hard to verify the usefulness of MPEG-A in the real applications because there is still no real system that fully implements this standard. In this thesis, a design and implementation of a multimedia retrieval system based on MPEG-A standard on PC and mobile device is presented. Furthermore, an extension of MPEG-A for describing the metadata for video is also proposed. It is selected and defined as a subset of MPEG-7 MDS[4] and TV-anytime[5] for video that is useful and manageable in the mobile environments. In order to design the multimedia retrieval system based on MPEG-A, we define the system requirements in terms of portability, extensibility, compatibility, adaptability, efficiency. Based on these requirements, we design the system which composed of 3 layers: Application Layer, Middleware Layer, Platform Layer. The proposed system consists of two sub-parts, client-part and server-part. The client-part consists of MAF authoring tool, MAP player tool and MAF searching tool which allow users to create, play and search the MAF files, respectively. The server-part is composed of modules to store and manage the MAF files and metadata extracted from MAF files. We show the usefulness of the proposed system by implementing the client system both on MS-Windows platform on desk-top computer and WIPI platform on mobile phone, and validate whether it to satisfy all the system requirements. The proposed system can be used to verify the specification in the MPEG-A, and to proves the usefulness of MPEG-A in the real application.

Effect of Acupuncture on Regional Cerebral Blood Flow at Acupoints GV 20, GV. 26, LI. 4, ST. 36, SP. 6 Evaluated by Tc-99m ECD Brain SPECT (Tc-99m ECD 뇌혈류 SPECT를 이용한 백회, 인중, 합곡, 족삼리, 삼음교에서 체침의 뇌혈류에 대한 효과)

  • Song, Ho-Chun;Bom, Hee-Seung;Kang, Hwa-Jeong;Ahn, Soo-Gi;Kim, Seong-Min;Jeong, Hwan-Jeong;Kim, Ji-Yeul
    • The Korean Journal of Nuclear Medicine
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    • v.34 no.6
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    • pp.456-464
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    • 2000
  • Purpose: To evaluate the effect of acupuncture on regional cerebral blood flow (rCBF) at acupoints suggested by oriental medicine to be related to the treatment of cerebrovascular diseases. Materials and Methods: Rest/acupuncture-stimulation Tc-99m ECD brain SPECT using a same-dose subtraction method was performed on 54 normal volunteers (34 males, 20 females, age range from 18 to 62 years) using six paradigms: acupuncture at acupoints GV. 20, GV. 26, LI. 4, ST. 36 and SP. 6. In the control study, needle location was chosen on a non-meridian focus 1 cm posterior to the right fibular head. All images were spatially normalized, and the differences between rest and acupuncture stimulation were statistically analyzed using SPM$^{(R)}$ for Windows$^{(R)}$. Results: Acupuncture applied at acupoint GV. 20 increased rCBF in both the anterior frontal lobes, the right frontotemporal lobes, and the left anterior temporal lobe and the left cerebellar hemisphere. Acupuncture at GV 26 increased rCBF in the left prefrontal cortex. Acupuncture at LI. 4 increased rCBF in the left prefrontal and both the inferior frontal lobes, and the left anterior temporal lobe and the left cerebellar hemisphere. Acupuncture at ST. 36 increased rCBF in the left anterior temporal lobe, the right inferior frontal lobes, and the left cerebellum. Acupuncture at SP. 6 increased rCBF in the left inferior frontal and anterior temporal lobes. In the control stimulation, no significant rCBF increase was observed. Conclusion: The results demonstrated a correlation between stimulation at each acupoint with increase in rCBF to the corresponding brain areas.

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Birth and Infant Death Reporting System via Computer Network (출생 및 영아사망 신고체계 및 전산정보체계 개발)

  • Park, Jung-Han;Lee, Young-Sook;Rhee, Jung-Ae;Cho, Hyun;Chung, Young-Hae;Park, Soon-Woo;Jun, Hae-Ri
    • Health Policy and Management
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    • v.8 no.2
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    • pp.125-148
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    • 1998
  • Accurate vital statistics are essential for a national health planning and evaluation. Among various vital statistics, birth and death rates, and infant and matemal mortality rates together with the causes of death are the very basic ones for above purposes as well as for the maternal and child health management. These statistics are based on the birth and death reports. It is required by law to report every birth and death within one month after its occurrence. However, in case of a neonatal death occurring prior to the birth report, most of the birth and death are not reported. Thus accurate infant and maternal mortality rates are not available yet in Korea. The main objective of this study is to develop a birth and infant death reporting system via computer network. We designed a new birth report form based on the current form and data from the analysis of medical record forms of 14 hospitals. A new form is basically addition of essential medical information to the current birth report form. Since a revision of the rules and regulations related wtih the birth report is necessary to use a new form, we kept the current from intact to make it acceptable to the government office for a field trial. We also developed computer programs for data input for birth and death reports at a medical faciltiy, data processing for production of maternal and child health indices at a health center, and management of maternal and child health services including immunization and postantal care at health center. The birth certificate and birth report can be printed out at a medical facility. The computer packages were programmed by Borland Delphi 3.0 and can be run under Windows 95 system. We proposed a new birth and death reporting system via computer network after a field trial for data input, transmission, and processing. The medical and demographic data o birth and death at medical facilities will be sent to health centers directly via computer network. The health center will retain the medical data for analysis and forward only the data for birth and death reports required by current regulations to the Dong, Up, or Myun Office. Once the birth or death is reported via computer network to the Dong Office, then the Dong Office will notify the baby's mother of the birth report and request to submit the baby's name by mail. When the baby's name its submitted. the Dong Office will forward the birth reports to the Common Court and Statistics Agency in the same way as the current system, Upon the completion of birth registration of the Common Court, the court will issue the birth certificate to mother which will be used in lieu of the family record. The advantages of proposed birth and death reporting system via computer network ar as follows ; I) The accuracy, timing, and completeness of reporting will be improved and more accurate maternal and child health indices can be obtained, ii) The maternal and child health services of health center will be obtained, iii) Epidemiologic data for pregnancy and birth can be obtained, iv) Manpower for birth and death reporting will be saved.

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A Study on the Realities of Custom-made Clothing Production in Middle-aged Women's Clothing Firms (중년여성복업체(中年女性服業體)의 맞춤복(服) 생산실태(生産實態) 연구(硏究))

  • Park, Yu-Jeong;Sohn, Hee-Soon
    • Journal of Fashion Business
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    • v.6 no.2
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    • pp.1-16
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    • 2002
  • The need for ready-to-wear clothing increases as the problem comes to arise from the fit of custommade clothing due to the characteristics of middle-aged women's somatotype. At this point of time, a study on the realities of production of custom-made clothing in middle-aged women's clothing business firms is of very greatly significance. Therefore, this study was intended to identify the problem and improvements through the survey research of production of custom-made clothing in middle-aged women's clothing business firms and further present the plan for development of custom-made clothing business. The questionnaire was framed based on the contents extracted from the preliminary questionnaire research for the pattern section chief of each business firm. Collected data were statistically processed using the SPSS 10.0 Windows program. As a result, the following findings were obtained: 1. The target age of the middle-aged women's clothing business firms ranged from more than 45 years to less than 50 years of age. Clothing business firms much made inroads into the ready-to-wear clothing market largely in the 1980s and the 1990s. Their active entry into the custom-made clothing market occurred in the 1970s and the 1980s. 2. In terms of the clothing production method of middle-aged women's clothing firms, some private boutique and designer brand clothing firms entered the clothing market with a focus on custom-made clothing in the beginning of its organization and introduced the production method of ready-to-wear clothing in accordance with changes in production methods and consumers' needs and wants. National brand clothing firms manufactured clothing with a focus on ready-to-wear clothing from the beginning of its organization, but at last they manufactured both partial custom-made and whole custom-made as the problem arose from ready-to-wear clothing. Seeing that their clothing production showed the ratio readyto-wear to custom-made clothing of 2.58:1. And it was found that the manufacture of ready-to-wear and custom-made clothing took into consideration the great difference in the pattern, size and design plan. The research of the clothing production process showed that whole custom-made and partial custommade were distinguished according to whether or not the sample was presented. 3. The ready-to-wear pattern of middle-aged women's clothing firms were used with a focus on the 'patternmaker-developed pattern' and company-developed pattern'. Most clothing businesses produced clothing in 4 to 5 basic sizes, which is found to be insufficient to complement the physical characteristics of middle-aged women with many specific somatotypes. In the pattern of custom-made clothing, the 'pattern of ready-to-wear were applied' or the 'customized pattern was developed'. Actual measurements were most used as the size of custom-made, and accordingly it is predicted that the level of satisfaction is higher with the fit of custom-made clothing than that of ready-to-wear. The selling place and the head office showed the similar percent as the place for measuring the size of custom-made clothing. Size measurers were mostly the shop master. And it was found that most clothing business firms had a problem when the measured size was applied to the pattern. Accordingly, it is necessary to provide education on size measurement for shop masters. 4. It was found that in the middle-aged women's clothing firms, the pattern correction of the length of sleeve, jacket and slacks occupied the highest percent. Accordingly, it is necessary to provide for the size system to complement the accurate somatotype characteristics of middle-aged women. 5. In custom-made clothing customer management, most firms engaged in customer somatotype management through size management. They provided customers with commodity information by informing them of the sales and event period and practiced human management for customers by maintaining the get-together and friendly relationship. 6. Middle-aged women's clothing businesses responded that it would be necessary to improve the fit of custom-made clothing and complement their pursuit for individuality as the plan to improve its quality. In consequence, it suggests that middle-aged women's clothing businesses should provide middle-aged women with the clothing of better-suited size and refined design. Middle-aged women's clothing businesses responded that it was the most urgent task to form the custom-made clothing manufacturing team as the plan to expand the custom-made clothing market, which is identified as their emphasis on the systematized production of custom-made clothing.

Influence of Environmental Living Standards on Helicobacter pylori Infection in Korean Elementary School Children (서울 지역 초등학생의 생활환경과 Helicobacter pylori 양성률)

  • Kim, Je-Woo;Kim, Hyo-Shin;Chung, Ki-Sup
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.4 no.1
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    • pp.10-17
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    • 2001
  • Purpose: We measured anti-H. pylori IgG in Korean elementary school children living in Shinchon area of Seoul, Korea to evaluate the influence of environmental living standards on H. pylori infection. Methods: IgG antibodies to H. pylori were measured in plasma using a commercial ELISA kit (GAP IgG Helicobacter pylori, Bio-Rad Laboratories Inc., Hercules, CA, USA). Information on environmental status such as place of birth, parental income, type of housing, number of persons in the household, parents' occupation, family history of peptic ulcer disease and gastric cancer was obtained. Statistical analysis was done by Chi-square and logistic regression test using SPSS $7.0^{TM}$ for Windows. Results: Study subjects consisted of 571 children, and the age distribution ranged from 6.0 to 13.6 years with a mean of $9.6{\pm}1.8$ years. Male-to-female ratio was 1.1:1. The seropositive rates of H. pylori infection ranged from 10.4% in children aged 6 years to 30.9% in 12 year-old group, overall 16.8%. The prevalence of H. pylori infection progressively increased with age, but there was no significant difference in seropositive rates among children in different age groups (p=0.06). Seropositive rates of anti-H. pylori IgG on the basis of gender, place of birth, parental income, type of housing, parents' occupation, family history of peptic ulcer disease and gastric cancer showed no statistically significant difference. Interestingly, however, seropositive rate of anti-H. pylori IgG showed statistical significance in relation to number of persons in the household (p=0.003; Odds ratio 1.50 by logistic regression test). Conclusion: These results suggest that number of persons in the household is the most important factor among environmental living standards, and that risk of H. pylori infection increases by increment of 1.5 times as the number of persons in the household increases by one.

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Priority Order of Decisional Factors and Conceptual Construct of Security Martial Arts' Spirit (경호무도 정신특성 요인의 상대적 중요도 평가)

  • Kim, Dong-Hyun
    • Korean Security Journal
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    • no.32
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    • pp.7-32
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    • 2012
  • This study aimed to evaluate the relative status using Analytic Hierarchy Process(AHP) on the spiritual factors of the security martial arts for the guards to perform the best security service. There were 540 participants who were students majored in security martial arts, workers for security and specialists of practical and theoretical security martial arts for this study. The exploratory and confirmatory factor analysis were carried out using the selecting data through literature reviews in the level of the factor-extraction about the spiritual characteristics. The specialists' survey was conducted on the relative status among factors using the spiritual concept structure based on the studied above. Selected data was calculated with SPSS 18.0 for windows, AMOS 5.0, and Expert Choice 2000 software. The conclusion can be made through those process above. First, 4 general factors and 20 detailed factors were found as the result of the factor exploration related to the spiritual characteristics of the security martial arts. The result which was verified on Construction validity of searched factors had stable figures on every standard. In other words, the participants for survey on this study "Spiritual characteristic concepts of the security martial arts" can be evaluated it is valid. The general factors of security martial arts' spirit were conceptualized with Psychological spirit, ethical spirit, martial art spirit, practical spirit through the naming process on the general factors of the security martial arts' spiritual characteristic concepts. The detailed factors of security martial arts' spirit were concentration, self-confidence, self-management, immersion, self-esteem in psychological spirit and sacrifice, justice, royalty, peace, sense of duty in ethical spirit and courtesy, toughness, defense, balance of mind and body, bravery in martial arts and responsibility, cooperation, modesty, determination, professionalism in practical spirit of security martial arts. That is, the conceptualization of security martial arts' spirit was verified that it had validity. Second, the hierarchical model of the security martial arts was composed with 4 superordinate concepts and 20 subordinate concepts. As the result of evaluating relative status based on Spiritual characteristics-hierarchy model, the impotance was proven in order of ethical spirit(.482), martial art spirit(.248), practical spirit(.188), psychological spirit(.083). Also the importance related to spiritual characteristics of security martial arts on subordinate concepts was proven in order of sacrifice(.252), courtesy(.110), sense of duty(.108), responsibility(. 073), royalty(.053), toughness(.052), justice(.049), defense(.038), professionalism(.038), determination(.035), cooperation(.029), self-confidence (.026), bravery(.025), self-esteem(.024), balance of mind and body(.023), peace(.019), concentration(.014), modesty(.013), self-management(.011), flow (.007). To sum up, the spiritual factor related to ethics such as sacrifice, justice, royalty, peace, sense of duty was the most important for the security martial arts.

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Analysis of the Risk Factors Influencing the Severity of Injury in Pediatric Multiple Trauma Patients (소아 다발성 외상 환자의 중증도에 영향을 미치는 위험인자에 관한 분석)

  • Lee, Gang-Wook;Kim, Sun-Pyo;Kim, Seong-Jung;Cho, Soo-Hyung;Cho, Nam-Soo
    • Journal of Trauma and Injury
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    • v.23 no.2
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    • pp.68-74
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    • 2010
  • Purpose: The purpose of this study is, first, to analyze the risk factors that influence the severity of injury in pediatric multiple trauma patients and, second, to present solutions for the problems related to the treatment of such patients. Our living situations are so complicated that the danger of accidents is truly open to children who are not prepared. We need to draw attention to the increased numbers of various accidents involving children. Methods: We studied patients who visited the Emergency Medical Center at Chosun University Hospital from January 1, 2006, to December 31, 2008. Using medical records, we evaluated the general characteristics: the mechanism of injury, the vital signs, the revised trauma score (RTS), the injury severity score (ISS), and the hemoglibin value, which was checked at the time of visit, and the presence or the absence of emergent on regular surgery. We divided the level of injury as follows: light level (1-8 points), mid level (9-15 points), and serious level (above 16 points). We analyzed the medical data by using SPSS 17.0 for windows. Results: The average age of the patients examined was 8.6 years. The number of 6- to 11-year-old patients was 96, which was the largest, but the degree of injury severity was the highest among infant (0-2 years), according to ISS 7.95(${\pm}6.85$). The frequency of accidents was highest on sunny days, and most accidents occurred from 16:00 to 20:00. The cause of multiple trauma for children was the greatest in the traffic accident, (95 patients, 49.0%). In addition, the trauma caused by traffic accidents showed the highest ISS value ($9.02{\pm}6.42$) and the most serious degree (P=0.004). The ISS level of injury ($8.40{\pm}6.64$) for patients moved from a secondary hospital was higher than that ($6.49{\pm}5.57$) for patients who visited the medical center directly. The severity of injury was highest for patients who used a 119 ambulance ($8.84{\pm}5.80$). According to the injured parts of body, Injuries to the arms and the feet most frequent (79 patients, 40.7%), but the level of injury was the highest for internal organs and chest, $16.42{\pm}8.56$ and $11.23{\pm}6.97$, respectively. Conclusion: We used Abbreviated Injury Scale (AIS) in order to examine the characteristics by injured body part for pediatric multiple trauma patients. Because the degree of injury was the highest for internal organs or the chest, we need to more seriously examine and provide for patients who are suspected of having injuries to the internal organs or the chest. We need to quickly determine the need for surgery in patients with serious injuries to the arms and the feet, which is the greatest in frequency. In particular, we need to consider the surgical care of patients who are not very high in the severity of injury to their brains.

Development of a Dose Calibration Program for Various Dosimetry Protocols in High Energy Photon Beams (고 에너지 광자선의 표준측정법에 대한 선량 교정 프로그램 개발)

  • Shin Dong Oh;Park Sung Yong;Ji Young Hoon;Lee Chang Geon;Suh Tae Suk;Kwon Soo IL;Ahn Hee Kyung;Kang Jin Oh;Hong Seong Eon
    • Radiation Oncology Journal
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    • v.20 no.4
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    • pp.381-390
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    • 2002
  • Purpose : To develop a dose calibration program for the IAEA TRS-277 and AAPM TG-21, based on the air kerma calibration factor (or the cavity-gas calibration factor), as well as for the IAEA TRS-398 and the AAPM TG-51, based on the absorbed dose to water calibration factor, so as to avoid the unwanted error associated with these calculation procedures. Materials and Methods : Currently, the most widely used dosimetry Protocols of high energy photon beams are the air kerma calibration factor based on the IAEA TRS-277 and the AAPM TG-21. However, this has somewhat complex formalism and limitations for the improvement of the accuracy due to uncertainties of the physical quantities. Recently, the IAEA and the AAPM published the absorbed dose to water calibration factor based, on the IAEA TRS-398 and the AAPM TG-51. The formalism and physical parameters were strictly applied to these four dose calibration programs. The tables and graphs of physical data and the information for ion chambers were numericalized for their incorporation into a database. These programs were developed user to be friendly, with the Visual $C^{++}$ language for their ease of use in a Windows environment according to the recommendation of each protocols. Results : The dose calibration programs for the high energy photon beams, developed for the four protocols, allow the input of informations about a dosimetry system, the characteristics of the beam quality, the measurement conditions and dosimetry results, to enable the minimization of any inter-user variations and errors, during the calculation procedure. Also, it was possible to compare the absorbed dose to water data of the four different protocols at a single reference points. Conclusion : Since this program expressed information in numerical and data-based forms for the physical parameter tables, graphs and of the ion chambers, the error associated with the procedures and different user could be solved. It was possible to analyze and compare the major difference for each dosimetry protocol, since the program was designed to be user friendly and to accurately calculate the correction factors and absorbed dose. It is expected that accurate dose calculations in high energy photon beams can be made by the users for selecting and performing the appropriate dosimetry protocol.

Improved Activity Estimation using Combined Scatter and Attenuation Correction in SPECT (단일광자방출단층촬영 영상에서 산란 및 감쇠 보정에 위한 절대방사능 측정)

  • Lee, Jeong-Rim;Choi, Chang-Woon;Lim, Sang-Moo;Hong, Seong-Wun
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.4
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    • pp.382-390
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    • 1998
  • Purpose: The purpose of this study was to evaluate the accuracy of radioactivity quantitation in Tc-99m SPECT by using combined scatter and attenuation correction. Materials and Methods: A cylindrical phantom which simulates tumors (T) and normal tissue (B) was filled with varying activity ratios of Tc-99m. We acquired emission scans of the phantom using a three-headed SPECT system (Trionix, Inc.) with two energy windows (photopeak window: $126{\sim}154keV$ and scatter window: $101{\sim}123keV$). We performed the scatter correction with dual-energy window subtraction method (k=0.4) and Chang attenuation correction. Three sets of SPECT images were reconstructed using combined scatter and attenuation correction (SC+AC), attenuation correction (AC) and without any correction (NONE). We compared T/B ratio, image contrast [(T-B)/(T+B)] and absolute radioactivity with true values. Results: SC+AC images had the highest mean values of T/B ratios. Image contrast was 0.92 in SC+AC, which was close to the true value of 1, and higher than AC (0.77) or NONE (0.80). Errors of true activity by SPECT images ranged from 1 to 11% for SC+AC, $22{\sim}47%$ for AC, and $2{\sim}16%$ for NONE in a phantom which was located 2.4cm from the phantom surface. In a phantom located 10.0cm from the surface, SC+AC underestimated by 24%, NONE 40%. However, AC overestimated by 10%. Conclusion: We conclude that accurate SPECT activity quantitation of Tc-99m distribution can be achieved by dual window scatter correction combind with attenuation correction.

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