• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권9호
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• pp.3751-3770
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• 2015

Many sorts of image processing software facilitate image editing and also generate a great number of doctored images. Forensic technology emerges to detect the unintentional or malicious image operations. Most of forensic methods focus on the detection of single operations. However, a series of operations may be used to sequentially manipulate an image, which makes the operation detection problem complex. Forensic investigators always want to know as much exhaustive information about a suspicious image's entire processing history as possible. The detection of the operation chain, consisting of a series of operations, is a significant and challenging problem in the research field of forensics. In this paper, based on the histogram distribution uniformity of a manipulated image, we propose an operation chain detection scheme to identify histogram equalization (HE) followed by the dither-like operation (DLO). Two histogram features and a local spatial feature are utilized to further determine which DLO may have been applied. Both theoretical analysis and experimental results verify the effectiveness of our proposed scheme for both global and local scenarios.

• 대한방사선기술학회지:방사선기술과학
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• 제8권2호
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• pp.29-45
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• 1985

Computed Tomography Scanner (CT) is highly expensive in operation as well as purchasing. That reason may cause not only to increase the burden of patients but also to waste the capital resources leading to financial difficulties. However the numbers of CT installed throughout the country is increasing, because of efficiency in medical care, patient's concern, competitions among the hospitals within the same area. In the non-Metropolitan area the scanners were expected to be less utilized and less profitable. Nine hospitals equipped with the CT were studied on the utilization of that equipment during the period from November 1984 to February 1985 in non-Metropolitan area and break-even point in one hospital was analyzed for estimating profitabilities. The results were as follows ; 1. Among those nine hospitals, four hospitals had less than 400 beds, which is one of the restrictive minimum standards on the installation of Whole-body Computed Tomography Scanner. 2. The operating time during the normal operation period was longer than those of any other studies, but the accumulated down time was also longer than those of any other studies. The average number of scanning per week for each CT was 45, while the estimated number of for the break-even point was 56.7 cases. 3. When the downtime was excluded in calculating the average operation would be much closer to the cases for the break-even point. Therefore the break-down of the equipment was to be a main cause of the low profitability. 4. The average scanning rate for head area was 33.6%, however three of the nine hospitals showed about 20%. 5. If scanning ratio for the body parts excepting head was increased, the number of scanning for the break-even point would be diminished. 6. The small size hospital especially located near the Metropolitan area showed largest loss in the CT operation. In purchasing the highly expensive equipments in hospitals, demand should be taken into account and planning is recommended.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.10-11
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• 2021

Demands for digital transformation of the construction industry are increasing to improve the accuracy of the construction operation planning and the performance of the construction operation. Even though large number of studies are being conducted to this date, most of the studies are not likely to be available on the real sites. Therefore, this study provides construction managers with a methodology of drawing construction performance indicators based on productivity analysis using Artificial Neural Network (ANN) models and Web-CYCLONE. This methodology is expected to have high utilization and precision of construction operation planning and management.

• 임상간호연구
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• 제16권3호
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• pp.63-71
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• 2010

Purpose: This study was conducted to evaluate the incidence and risk factors for surgical glove perforation during operation. Methods: During the month of december 2008, a total of 1,400 pairs of surgical gloves used in major operations was collected in a tertiary hospital. All gloves were examined immediately after operation using the standardized water-leak method to detect any perforation. Incidence of the glove perforation was counted according to the type of operation, operation time, the number of involved personnel, perforation sites, and the manufacturing companies. Results: Out of 2,800 gloves examined, 312 perforations were detected comprising 11.1% of samples. In terms of the type of operation, the perforation incidence varied from 5% to 20%, and the perforation rates in CS (20%) and NS (18%) (p<.001) were significantly higher than those in other departments. The 1st assistant or scrub nurse got glove perforation more frequently than the 2nd assistant or operator (p<.001). Longer operation time was associated with higher incidence of perforation evidently (p<.001). In terms of the sites, the thumb and index finger were more frequently perforated than other sites (4.1% and 3.4% respectively) without any differences between left and right side. Conclusion: Risk factors for glove perforation including the department of operation, operation time, participating personnel, and location of perforation should be taken into account to improve surgical safety.

• 한국도로학회논문집
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• 제15권3호
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• pp.159-167
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• 2013

PURPOSES: The purpose of this study is to develop an effectiveness analysis method of exclusive median bus lanes, which is necessary in order to improve operation efficiency of exclusive median bus lanes. METHODS : The operation characteristics of "signalized intersection including exclusive median bus lanes" and "normal signalized intersection" were investigated and the existing capacity analysis method was also reviewed to analyze the effectiveness of exclusive median bus lanes. Delay reduction of passengers using exclusive median bus lanes which can be considered as the benefit of exclusive median bus lanes and the number of people in buses were included in the proposed effectiveness analysis method. RESULTS : It was found that the proposed method expresses properly the effectiveness of exclusive median bus lanes through performing sensitivity analysis and analyzing with the real data of the number of people in buses and passenger cars. It was also found that the proposed method demonstrates the effectiveness that measure of effectiveness of signalized intersections is changed to "sec/person". CONCLUSIONS : It was concluded that the method is a proper effectiveness analysis method because it can reflect the benefit of passengers in buses.

• 정보학연구
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• 제2권2호
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• pp.145-161
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• 1999

본 논문에서는 캐리 전파가 없어 고속연산이 가능한 잉여 수 체계를 이용하여 고속으로 동작할 수 있는 역전파 신경회로망을 설계방법을 제안하였다. 설계된 신경회로망은 잉여수계를 이용한 MAC 연산기와 혼합계수 변환을 이용한 시그모이드 함수 연산 부로 구성되며, 설계된 회로는 VHDL로 기술하였고 Compass 툴로 합성하였다. 실험결과, 가장 나쁜 경로일 경우, 약 19nsec의 지연속도를 보였고, 기존의 실수 연산기에 비하여 약 40%정도 하드웨어 크기를 줄일 수 있었다. 본 논문에서 설계한 신경회로망은 실시간 처리를 요하는 병렬분산처리 시스템에 적용될 수 있을 것으로 기대된다.

• 한국사회복지학
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• 제52권
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• pp.117-141
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• 2003

본 연구는 부산지역 사회복지관의 투입 요소와 산출 요소간의 효율성의 관계를 분석한 연구이다. 사회복지관의 효율성 평가를 위해 비영리기관에서 많이 활용되고 있는 자료포락분석(DEA)을 사용하였으며, 자료는 2001년 부산광역시에 제출한 사업보고 자료를 활용하였다. 본 연구에서는 4가지 다른 모델을 설정하여 부산지역 전체 45개 기관을 전수조사 하였다. 4가지 모델을 보면, 전 모델의 산출은 연간 프로그램 이용자의 연인원을 중심으로 투입의 변수에 따라 모델을 구분하였다. 모델 1; 투입에 사회복지사의 인력 수와 사회복지사 인건비, 모델 2; 투입에 총 직원 수, 연간 총 운영비, 모델 3; 투입에 총 직원 수, 연간 자원봉사자 수, 운영기간, 모델 4; 투입에 총 직원 수, 연간 자원봉사자 수, 운영기간, 연간 총 운영비를 설정하여 효율성을 분석하였다. 본 연구의 결과는 다음과 같다. (1) 전체 45개 사회복지관에서 35-55%만이 상대적으로 효율적인 사회복지관으로 평가되고 있는 것으로 나타났다. 각 모델별로 평균 효율치를 살펴보면, 모델 1은 .8735, 모델 2는 .7048, 모델 3은 .4941, 모델4는 .5097로 나타났다. (2) 모든 기관이 효율이 가장 높은 효율점수 1이 되기 위해서 어떻게 변화되어야 하는가를 산출물을 기준으로 하여 모델 1, 2, 3, 4로서 살펴보았다. 사회복지기관에서 주요한 투입변수인 인력과 예산부분에 있어서 어느 정도의 변화가 필요한지를 모델 1, 2, 3, 4를 전체적으로 살펴본 결과 인력과 예산부분에 있어서 변화가 필요한 기관이 전체 45곳 중 41곳이었으며 이 기관은 모두 현재보다 인력이나 예산부분의 증가를 요구되는 것으로 나타났다. 이 중에서도 인력적인 부분과 예산부분의 증가가 모두 필요한 기관은 보강이 필요한 41기관 중 60%에 해당하는 25곳이었으며, 예산의 증액만 요청되는 기관은 6곳, 인력의 보강만 필요한 기관은 10곳으로 나타났다. 따라서 부산지역의 대부분의 사회복지기관이 현재의 산출량에 대해 가장 효율적으로 운영되기 위해서는 개별기관별로 예산과 인력의 보강이 필요한 것으로 나타났다.

• 산업공학
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• 제17권2호
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• pp.233-241
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• 2004

The main subject to become a hub port is automation. The automated container terminal has already operated in advanced ports and it has been planned for the basic planning and operation design in domestic case. The key of automated container terminal is effective operation of both ATC(automated transfer crane) and AGV(automated guided vehicle) which is automated handling equipments. This is essential to productivity of automated container terminal. This study suggests the most optimal method of equipment operation in order to minimize loading time using each three types of effective ATC operation methods and AGV dispatching rules in automated container terminals. As the automated equipment operation causes unexpected deadlocks or interferences, it should be proceeded on event-based real time. Therefore we propose the most effective ATC operation methods and AGV dispatching rules in this paper. The various states occurred in real automated container terminals are simulated to evaluate these methods. This experiment will show the most robust automated equipment operation method on various parameters(the degree of yard re-marshaling, the number of containers and AGV)

• 한국안전학회지
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• 제29권3호
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• pp.129-135
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• 2014

The number of abnormal operation procedures (AOPs) for mitigating a plant abnormal status amounts to about one hundreds for the most of 1000MWe optimized power plant (OPR1000) and it is expected that the number of AOPs would be increased to cope with an abnormal status occurred newly. However, it is not well organized for operators to select a proper AOP from alarms occurred in main control room (MCR) during a plant abnormal status. It may be a burden to operators since the selection of AOP to respond an abnormal status is authorized by operators. When multiple alarms occur in MCR, it would take more time to respond them than a single alarm. To reduce the efforts, various MCR operation support systems have been developed. The purpose of this study was to develop a multi-alarm pattern card to select an appropriate AOP effectively when multiple alarms occurs in a single upper layout (UL) of MCR. It can be applied for an operation support tool as well as an education tool.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.809-810
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• 2006

An H.264 algorithm is commonly used for video compression applications. This algorithm requires a large number of data computations, for example, the sum of absolute difference (SAD) operation. We analyzed H.264 reference encoding workloads. The H.264 encoding program has 8.78% SAD operation. The SAD operation is to sum up 16 difference-values in H.264 $4{\times}4$ sub-blocks. In order to accelerate SAD operations, we implemented an application specific instruction-set processor (ASIP) that can execute SAD and data transfer instructions. The proposed coprocessor has an absolute value generator and a carry save adder (CSA) unit to sum up 8 difference-values per one clock cycle. We completed SAD operation in 2 clock cycles. Experimental results show that the performance is improved by 34% of total execution time.