• Journal of Biosystems Engineering
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• 제4권2호
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• pp.64-64
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• 1979

Low-temperature drying systems have been extensively used for drying cereal grain such as shelled corn and wheat. Since the 1973 energy crisis, many researches have been conducted to apply solar energy as supplemental heat to natural air drying systems. However, little research on rough rice drying has been done in this area, especially very little in Korea. In designing a solar drying system, quality loss, airflow requirements, temperature rise of drying air, fan power and energy requirements should be throughly studied. The factors affecting solar drying systems are airflow rate, initial moisture content, the amount of heat added to drying air, fan operation method and the weather conditions. The major objectives of this study were to analyze the effects of the performance factors and determine design parameters such as airflow requirements, optimum bed depth, optimum temperature rise of drying air, fan operation method and collector size. Three hourly observations based on the 4-year weather data in Chuncheon area were used to simulate rough rice drying. The results can be summarized as follows: 1. The results of the statistical analysis indicated that the experimental and predicted values of the temperature rise of the air passing through the collector agreed well.2. Equilibrium moisture content was affected a little by airflow rate, but affected mainly by the amount of heat added, to drying air. Equilibrium moisture content ranged from 12.2 to 13.2 percent wet basis for the continuous fan operation, from 10.4 to 11.7 percent wet basis for the intermittent fan operation respectively, in range of 1. 6 to 5. 9 degrees Centigrade average temperature rise of drying air.3. Average moisture content when top layer was dried to 15 percent wet basis ranged from 13.1 to 13.9 percent wet basis for the continuous fan operation, from 11.9 to 13.4 percent wet basis for the intermittent fan operation respectively, in the range of 1.6 to 5.9 degrees Centigrade average temperature rise of drying air and 18 to 24 percent wet basis initial moisture content. The results indicated that grain was overdried with the intermittent fan operation in any range of temperature rise of drying air. Therefore, the continuous fan operation is usually more effective than the intermittent fan operation considering the overdrying.4. For the continuous fan operation, the average temperature rise of drying air may be limited to 2.2 to 3. 3 degrees Centigrade considering safe storage moisture level of 13.5 to 14 perceut wet basis.5. Required drying time decrease ranged from 40 to 50 percent each time the airflow rate was doubled and from 3.9 to 4.3 percent approximately for each one degrees Centigrade in average temperature rise of drying air regardless of the fan operation methods. Therefore, the average temperature rise of drying air had a little effect on required drying time.6. Required drying time increase ranged from 18 to 30 percent approximately for each 2 percent increase in initial moisture content regardless of the fan operation methods, in the range of 18 to 24 percent moisture.7. The intermittent fan operation showed about 36 to 42 percent decrease in required drying time as compared with the continuous fan operation.8. Drymatter loss decrease ranged from 34 to 46 percent each time the airflow rate was doubled and from 2 to 3 percent approximately for each one degrees Centigrade in average temperature rise of drying air, regardless of the fan operation methods. Therefore, the average temperature rise of drying air had a little effect on drymatter loss. 9. Drymatter loss increase ranged from 50 to 78 percent approximately for each 2 percent increase in initial moisture content, in the range of 18 to 24 percent moisture. 10. The intermittent fan operation: showed about 40 to 50 percent increase in drymatter loss as compared with the continuous fan operation and the increasing rate was higher at high level of initial moisture and average temperature rise.11. Year-to-year weather conditions had a little effect on required drying time and drymatter loss.12. The equations for estimating time required to dry top layer to 16 and 1536 wet basis and drymatter loss were derived as functions of the performance factors. by the least square method.13. Minimum airflow rates based on 0.5 percent drymatter loss were estimated.Minimum airflow rates for the intermittent fan operation were approximately 1.5 to 1.8 times as much as compared with the continuous fan operation, but a few differences among year-to-year.14. Required fan horsepower and energy for the intermittent fan operation were3. 7 and 1. 5 times respectively as much as compared with the continuous fan operation.15. The continuous fan operation may be more effective than the intermittent fan operation considering overdrying, fan horsepower requirements, and energy use.16. A method for estimating the required collection area of flat-plate solar collector using average temperature rise and airflow rate was presented.

• 대한환경공학회지
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• 제27권4호
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• pp.394-401
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• 2005

저온 플라즈마 연료개질 장치를 개발하여 여러 운전인자가 그 성능에 미치는 영향을 조사하였고 생성된 수소농후 개질가스를 무부하(Idle) 상태의 디젤엔진에 연소용 공기와 같이 주입하여 NO와 매연 저감효율에 미치는 영향을 조사하였다 전력 소모량이 증가할수록 개질반응의 점화가 더욱 용이하였으나 $H_2$ 농도, $H_2$ 수율, 에너지 전환율과 같은 저온 플라즈마 연료개질 장치의 성능은 O/C 비에 의해서만 영향을 받았는데 그 이유는 평형 반응온도가 O/C 비에 의하여 결정되기 때문이다. 저온 플라즈마 연료개질 장치에서의 $H_2$ 수율과 에너지 전환율은 O/C 비가 증가함에 따라 O/C 비가 $1.2{\sim}1.5$에서 33.4%와 66%의 최고값을 통과하였다. $H_2$ 수율과 에너지 전환율이 O/C 비가 $1.2{\sim}1.5$ 이하인 범위에서 O/C 비가 증가함에 따라 증가하는 이유는 O/C 비가 높아짐에 따라 완전 산화반응이 충분히 일어나서 반응온도가 높아지기 때문으로 보인다. O/C비가 $1.2{\sim}1.5$ 이상인 범위에서 O/C 비가 증가함에 따라 $H_2$ 수율과 에너지 전환율이 감소하는 현상은 과잉산소 조건에서 완전산화반응이 더욱 촉진되어 $H_2$ 수율과 에너지 전환율이 감소하였기 때문으로 보인다. 무부하 상태의 디젤엔진에 개질가스를 주입시 개질된 디젤/총디젤 무게비가 $18.2{\sim}23.5%$까지 증가할 때 NO저감효율과 매연제거효율은 각각 68.8%와 55.5%까지 증가하였다.

• 지능정보연구
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• 제17권4호
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• pp.157-173
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• 2011

최근 인터넷 사용의 증가에 따라 네트워크에 연결된 시스템에 대한 악의적인 해킹과 침입이 빈번하게 발생하고 있으며, 각종 시스템을 운영하는 정부기관, 관공서, 기업 등에서는 이러한 해킹 및 침입에 의해 치명적인 타격을 입을 수 있는 상황에 놓여 있다. 이에 따라 인가되지 않았거나 비정상적인 활동들을 탐지, 식별하여 적절하게 대응하는 침입탐지 시스템에 대한 관심과 수요가 높아지고 있으며, 침입탐지 시스템의 예측성능을 개선하려는 연구 또한 활발하게 이루어지고 있다. 본 연구 역시 침입탐지 시스템의 예측성능을 개선하기 위한 새로운 지능형 침입탐지모형을 제안한다. 본 연구의 제안모형은 비교적 높은 예측력을 나타내면서 동시에 일반화 능력이 우수한 것으로 알려진 Support Vector Machine(SVM)을 기반으로, 비대칭 오류비용을 고려한 분류기준값 최적화를 함께 반영하여 침입을 효과적으로 차단할 수 있도록 설계되었다. 제안모형의 우수성을 확인하기 위해, 기존 기법인 로지스틱 회귀분석, 의사결정나무, 인공신경망과의 결과를 비교하였으며 그 결과 제안하는 SVM 모형이 다른 기법에 비해 상대적으로 우수한 성과를 보임을 확인할 수 있었다.

• 천문학회보
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• 제39권2호
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• pp.90-90
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• 2014

The Immersion Grating Infrared Spectrometer (IGRINS) is the first astronomical spectrograph that uses a silicon immersion grating as its dispersive element. IGRINS fully covers the H and K band atmospheric transmission windows in a single exposure. It is a compact high-resolution cross-dispersion spectrometer whose resolving power R is 40,000. An individual volume phase holographic grating serves as a secondary dispersing element for each of the H and K spectrograph arms. On the 2.7m Harlan J. Smith telescope at the McDonald Observatory, the slit size is $1^{{\prime}{\prime}}{\times}15^{{\prime}{\prime}}$. IGRINS has a plate scale of 0.27" pixel-1 on a $2048{\times}2048$ pixel Teledyne Scientific & Imaging HAWAII-2RG detector with a SIDECAR ASIC cryogenic controller. The instrument includes four subsystems; a calibration unit, an input relay optics module, a slit-viewing camera, and nearly identical H and K spectrograph modules. The use of a silicon immersion grating and a compact white pupil design allows the spectrograph collimated beam size to be 25mm, which permits the entire cryogenic system to be contained in a moderately sized ($0.96m{\times}0.6m{\times}0.38m$) rectangular Dewar. The fabrication and assembly of the optical and mechanical components were completed in 2013. From January to July of this year, we completed the system optical alignment and carried out commissioning observations on three runs to improve the efficiency of the instrument software and hardware. We describe the major design characteristics of the instrument including the system requirements and the technical strategy to meet them. We also present the instrumental performance test results derived from the commissioning runs at the McDonald Observatory.

• Asia pacific journal of information systems
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• 제20권3호
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• pp.191-204
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• 2010

Recently, the CO2 emission and energy consumption have become critical global issues to decide the future of nations. Especially, the spread of IT products and the increased use of internet and web applications result in the energy consumption and CO2 emission of IT industry though information technologies drive global economic growth. EU, the United States, Japan and other developed countries are using IT related environmental regulations such as WEEE(Waste Electrical and Electronic Equipment), RoHS(Restriction of the use of Certain Hazardous Substance), REACH(Registration, Evaluation, Authorization and Restriction of CHemicals) and EuP(Energy using Product), and have established systematic green business/IT strategies to enhance the competitiveness of IT industry. For example, the Japan government proposed the "Green IT initiative" for being compatible with economic growth and environmental protection. Not only energy saving technologies but energy saving systems have been developed for accomplishing sustainable development. Korea's CO2 emission and energy consumption continuously have grown at comparatively high rates. They are related to its industrial structure depending on high energy-consuming industries such as iron and steel Industry, automotive industry, shipbuilding industry, semiconductor industry, and so on. In particular, export proportion of IT manufacturing is quite high in Korea. For example, the global market share of the semiconductor such as DRAM was about 80% in 2008. Accordingly, Korea needs to establish a systematic strategy to respond to the global environmental regulations and to maintain competitiveness in the IT industry. However, green competitiveness of Korea ranked 11th among 15 major countries and R&D budget for green technology is not large enough to develop energy-saving technologies for infrastructure and value chain of low-carbon society though that grows at high rates. Moreover, there are no concrete action plans in Korea. This research aims to deduce the priorities of the Korean green business/IT strategies to use multi attribute weighted average method. We selected a panel of 19 experts who work at the green business related firms such as HP, IBM, Fujitsu and so on, and selected six assessment indices such as the urgency of the technology development, the technology gap between Korea and the developed countries, the effect of import substitution, the spillover effect of technology, the market growth, and the export potential of the package or stand-alone products by existing literature review. We submitted questionnaires at approximately weekly intervals to them for priorities of the green business/IT strategies. The strategies broadly classify as follows. The first strategy which consists of the green business/IT policy and standardization, process and performance management and IT industry and legislative alignment relates to government's role in the green economy. The second strategy relates to IT to support environment sustainability such as the travel and ways of working management, printer output and recycling, intelligent building, printer rationalization and collaboration and connectivity. The last strategy relates to green IT systems, services and usage such as the data center consolidation and energy management, hardware recycle decommission, server and storage virtualization, device power management, and service supplier management. All the questionnaires were assessed via a five-point Likert scale ranging from "very little" to "very large." Our findings show that the IT to support environment sustainability is prior to the other strategies. In detail, the green business /IT policy and standardization is the most important in the government's role. The strategies of intelligent building and the travel and ways of working management are prior to the others for supporting environment sustainability. Finally, the strategies for the data center consolidation and energy management and server and storage virtualization have the huge influence for green IT systems, services and usage This research results the following implications. The amount of energy consumption and CO2 emissions of IT equipment including electrical business equipment will need to be clearly indicated in order to manage the effect of green business/IT strategy. And it is necessary to develop tools that measure the performance of green business/IT by each step. Additionally, intelligent building could grow up in energy-saving, growth of low carbon and related industries together. It is necessary to expand the affect of virtualization though adjusting and controlling the relationship between the management teams.

• 한국병원경영학회지
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• 제3권1호
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• pp.1-33
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• 1998

The purpose of this thesis is to study theoretical access to the methods that have been used for the research of occupational stress, thereby providing management methods of occupational stress of hospital workers. With a stress model of hospital workers set up from the viewpoint of organization management, 929 sets of questionnaires were collected from intern doctors, resident doctors, nurses, nursing aides, pharmacists, medical technicians, workers in patient affairs(reception and medical insurance workers), administrators and clerks from the 8 hospitals in Seoul with more than 500 beds. Upon variance analysis, correlation analysis and regression analysis of the collected questionnaires, this work examined how differences in stress caused by specific occupations and formulated a method of stress management for the hospital workers. The results are as follows. 1) If some duties of the nurses suffering from role-overloaded stress are transferred to the nursing aides dissatisfied with insufficient role, the two grunting groups can be satisfied at the same time. It is also necessary to transfer some jobs of the overloaded workers in patient affairs to the administrators, or the other way around. To reduce stress of conflict and ambiguity of role caused by the obscure division of roles between the workers, the role of each occupation should be delineated and the clear division of roles should be translated into action strictly according to that delineated. 2) Stress of inefficiency of organization from which the student doctors suffer can be relieved by management of participation. If they have access to the process of decision-making in general hospital affairs and consequently their understanding and the autonomy of job performance are promoted, such stress will be reduced. 3) To cope with stress of career development from which nurses, medical technicians, administrators, workers in patient affairs suffer, it is necessary to establish whether they have a chance to revive their careers, whether there are any ways of remotivation for less contributive workers, and whether they encourage each other to develope their careers. If they are given a chance to develope their careers, such stress will be relieved. 4) Pharmacists, suffering from stresses of living and personal relations, have strong cohesive power among themselves and organize a well-integrated team; thereby reducing the stress of personal relations and increasing productivity. 5) For administrators and student doctors confined to lesser social supports and for nurses and workers in patient affairs whose recognition of stress and job satisfaction are affected by social supports, emotional and informational supports for job performance help alleviate an individual's mental, and physical stress. 6) In addition to the above-mentioned stress-management methods, if an organizational coping strategy is provided according to the types of stress from the general viewpoint of the whole group of hospital workers, it would be of great help to managing stress. For example, the redesign of jobs, the management of objective, the improvement of working environment, the formation of an autonomous working group and various working plans can be set up for those who suffer from stress related to inappropriate role, while career counseling and development of career process can be provided for those dissatisfied with career development. Participation in the process of decision-making and the restructuring of the organization are needed for those who suffer from stress of malfunctioning organization, whereas creation of a supportive organizational atmosphere is desired for those who feel stressed due to personal relations. As well, such organizational coping strategies. as the increase of welfare facilities, seminars and educational programs and provision of health-promotion facilities can be provided.

• 벤처창업연구
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• 제1권1호
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• pp.127-156
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• 2006

본 연구는 중소기업청이 개설을 계획하고 EIP 사업을 추진한 호서대학교와 진주산업대학교 등 양 대학교의 EIP 사업추진 성공사례를 소개하였다. 현재 EIP가 확대 개편되어 전국 5개 대학교에서 벤처창업관련 대학원으로 운영하는 모범적 발전과정은 양 대학교의 EIP 사업추진 성공사례에 기인한다고 판단된다. 본 연구의 목적은 EIP 사업추진 성공사례를 분석하여 향후 단기 집중과정으로 벤처창업교육을 확산할 수 있는 방안을 모색하는데 있다. EIP의 성공요인은 다음과 같다. 첫째, 짜임새 있는 교육과정 모형을 만들었다. 둘째, 확고한 교육목표를 두었다. 셋째, 차별화된 교육내용을 구성하였다. 넷째, 교육성과를 모니터링하였다. 다섯째, 창업사례를 발표하는 기회를 자주 만들었다. 하지만 다음과 같은 애로요인도 있었다. 첫째, 교육목표를 달성하기 위한 교과과정 편성의 어려움이다. 둘째, 교육생의 교육동기를 사업기회의 발견으로 유도하는데 미흡하였다. 셋째, EIP예산 배정과 집행의 한계이다. 따라서 벤처창업 교육과정의 효율성을 제고하기 위해서는 다음과 같은 확산전략이 보완되어야 한다. 첫째, 벤처창업 교육과정의 지속적 재설계이다. 둘째, 창업교육내용의 특화이다. 셋째, EIP 운영의 자율성 확대이다. 넷째, 대학 간 교류 협력 활성화이다. 다섯째, 성과평가 체계를 구축하여 사업추진 동기를 부여하여야 한다.

• 정신신체의학
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• 제11권2호
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• pp.118-136
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• 2003

연구목적: '컴퓨터화된 검사'인 전산화 신경인지기능검사가 학령기 정상아동의 신경심리학적 발달특성을 반영하는 지를 알아보고자 하였다. 방 법: 2002년 6월부터 2003년 1월까지 평균 범위 이상의 지능을 유지하고 있고, 배제기준(rule out criteria)을 통과한 학년별 남녀 각각 10명씩, 120명의 정상아동에게 K-ABC, K-PIC 및 전산화 신경인지기능검사를 실시하였다. 결 과: 정상아동의 표집과정에서 지능의 통제와 엄격한 배제기준의 적용을 통하여 전체 아동의 21.1%가 분석과정에서 제외되었지만 학년별 인원과 성비를 동일하게 유지하면서 지능의 차이가 없는 연구 대상자 120명을 선발할 수 있었다. 학년에 따른 CNFT의 결과비교에서, 주의력 검사, 기억력 검사 및 고위인지기능검사 대부분에서 학년에 따른 유의한 차이가 있음을 확인하였으며, 주로 초등학교 저학년(1학년과 2학년)과 고학년(5학년과 6학년)에서 나타남을 확인하였다. 주의력 검사의 경우, 학년이 증가함에 따라 점차 수행이 행상되는 특성을 확인하였고, 단기기억력 검사에서 역방향 검사와 순방향검사의 차이, 연령에 따른 수행차이가 선행연구와 동일함을 발견할 수 있었다. 회상(recall) 과제로 구성된 언어청각검사와 재인(recognition)과제로 구성된 시각도형기억검사 또한 대인검사로 실시된 선행연구에서와 마찬가지로 연령에 따른 변화특성이 확인되었다. 고위인지기능검사에서도 주의력 검사 및 기억력 검사에서 연령에 따른 변화특성이 발견되었다. 결 론: 본 연구에서 성인을 대상으로 하여 개발된 CNFT가 아동의 신경심리학적 특성을 적절히 반영하고 있음을 확인할 수 있었고, 이를 위하여서는 연구 대상자의 표집단계에서부터 지적수준의 통제와 더불어 엄격한 배제기준의 적용이 필요함을 알수 있었다.

• 전기화학회지
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• 제10권4호
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• pp.283-287
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• 2007

한국에너지기술연구원에서는 중온 ($700{\sim}800^{\circ}C$) 작동용 연료극 지지체 평관형 SOFC 스택을 구성하는 단위 번들을 개발했다. 연료극 지지체 평관형 셀은 Ni/YSZ 서밋 연료극 지지체 튜브, 8몰% $Y_2O_3$ stabilized $ZrO_2$ (YSZ) 전해질, $LaSrMnO_3$ (LSM)과 LSM-YSZ composite 및 $LaSrCoFeO_3(LSCF)$로 구성된 다중층 공기극으로 구성됐다. 제조된 연료극지지체 평관형 셀은 유도 브레이징 법에 의해 페리틱 (ferritic) 금속 캡에 접합됐고, 공기극의 전류집전을 위해 공기극 외부에 Ag 선 및 $La_{0.6}Sr_{0.4}CoO_3(LSCo)$ paste를 이용했으며, 연료극의 전류집전은 Ni felt, wire, 그리고 paste를 이용했다. 단위 번들을 만들기 위한 연료극 지지체 평관형 셀의 반응 면적은 셀 당 $90\;cm^2$ 이었으며, 2개의 셀이 병렬로 연결되어 1개의 단위 번들이 됐고, 총 12개의 단위 번들이 직렬로 연결되어 스택을 구성한다. 공기 및 3%의 가습된 수소를 산화제 및 연료로 사용한 단위 번들의 운전 결과 최대 성능은 $800^{\circ}C$에서 $0.39\;W/cm^2$의 출력이 나타났다. 본 연구를 통해 연료극 지지체 평관형 SOFC 셀의 기본 기술과 KIER 만의 독특한 연료극 지지체 평관형 SOFC 스택을 구성하는 단위 번들의 개념을 확립할 수 있었다.

• 대한감각통합치료학회지
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• 제17권3호
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• pp.26-45
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• 2019

목적 : 본 연구의 목적은 작업치료사가 감각통합 중재를 실행하는데 필요한 역량을 기반으로 중재 과정 교육 커리큘럼 개발하고, 중재과정 실시 및 교육만족도 확인을 통하여 대한감각통합치료학회의 역량기반 중재 교육과정을 제시하는데 있다. 연구방법 : 본 연구는 대한감각통합치료학회의 2019년 중재과정에 참여한 작업치료사 9명과 강사 3명을 대상으로 하였다. 중재과정의 교육목표 설정은 참여자 설문조사 방법을 통하여 교육요구 분석방법을 사용하였다. 중재과정의 역량기반 교육 프로그램 초안 및 교육 방법은 강사회의를 통하여 결정하였다. 중재교육과정은 실행계획에 따라 5일간 실시하였으며, 교육 만족도와 각 역량지표에 대한 중재과정 전후의 수행도 변화를 조사하였다. 결과 : 교육목표는 교육요구 분석 결과를 반영하여 '감각통합중재의 임상추론 과정을 학습 하고 적용한다'와 '감각통합중재 원칙을 적용하여 중재한다'로 하였다. 역량기반 중재과정 교육커리큘럼은 교육목표에 따라 Data driven decision making process 및 Ayres Sensory Integration에 관한 강의, 워크샵, 토의, 그리고 사례 중재 등으로 구성하여 총 42시간 교육을 실시하였다. 중재과정 참여자의 교육 만족도는 평균 4.48±0.73이었고, 수퍼바이저의 교육 만족도는 평균 3.92±0.71이었다. 두 집단 모두에서 Data driven decision making process 강의와 중재 목표 수립 강의의 만족도가 가장 높았고, 그룹 활동 및 토의에 대한 만족도가 가장 낮았다. 중재과정 전후, 역량모델의 전문가 역량군에 포함된 분석기술 역량의 두 가지 행동지표가 수행도에서 유의미한 변화를 보였다. 결론 : 본 연구는 교육 개발에 필요한 체계적 과정을 거쳐 교육요구 조사, 교육 커리큘럼 개발과 실시, 교육 만족도 조사를 실행하였다는 점에서 의의가 있다. 대한감각통합치료학회 내의 다른 교육커리큘럼 개발 시 기초자료로 사용될 수 있을 것으로 생각된다.