구리와 니켈이 포함된 Fe-9Mn-0.2C-3Al-0.5Si 중망간강의 미세조직과 기계적 특성에 미치는 2상역 어닐링의 영향

이승완,신승혁,황병철,Lee, Seung-Wan,Sin, Seung-Hyuk,Hwang, Byoungchul 한국재료학회 2020 한국재료학회지 Vol.30 No.1

The effect of intercritical annealing temperature on the microstructure and mechanical properties of Fe-9Mn-0.2C-3Al-0.5Si medium manganese steels containing Cu and Ni is investigated in this study. Six kinds of medium manganese steels are fabricated by varying the chemical composition and intercritical annealing temperature. Hardness and tensile tests are performed to examine the correlation of microstructure and mechanical properties for the intercritical annealed medium manganese steels containing Cu and Ni. The microstructures of all the steels are composed mostly of lath ferrite, reverted austenite and cementite, regardless of annealing temperature. The room-temperature tensile test results show that the yield and tensile strengths decrease with increasing intercritical annealing temperature due to higher volume fraction and larger thickness of reverted austenite. On the other hand, total and uniform elongations, and strain hardening exponent increase due to higher dislocation density because transformation-induced plasticity is promoted with increasing annealing temperature by reduction in reverted austenite stability.

군 조직과 회계담당자의 특성이 국방회계정보의 발생액에 미치는 영향

이승완,윤병섭 한국기업경영학회 2015 기업경영연구 Vol.22 No.5

The aim of this study is to investigate whether the effects of military organizational and accountant’s characteristics on total accruals, quality, of accounting information. Especially, using the financial statements of ministry of national defense, this paper is based on the empirical approach. Governmental financial statements based on accrual and double-entry accounting system have disclosed since fiscal year 2011. The governmental financial statements including financial position, financial operations, the net asset change statement, and notes. The biggest difference between the governmental and the general corporate accounting standard is the structure of the national financial statements of public information users two weeks spending of appropriations areas of concern and a point was made around the cost of each program. This study executes this empirical analysis using a data set containing virtually sub corp of army, air force and navy for the period 2008-2014. As a result of analyzing the relationship between the organization and accrual characteristics are as follows: First, at a statistically significant level of negative forces between the scale and total accruals - it was relevant to the negative coefficient. It is interpreted that the larger the bag size can be higher the quality of accounting information in accordance with the political cost hypothesis. Second, if you have a relatively Welfare Center showed that increasing the size of accruals. This means that the more units to take advantage of them held the Welfare Hall to apply accounting standards can relatively be lower accruals to steam the quality of accounting information. Results of analysis of the relationship between military personnel of the properties and accruals accounting are as follows. First, the size of the accruals up to the more high rank bags of bottles and financial officers observed a phenomenon that is relatively small. The higher the rank the greater professionalism of accounting judgment on the interpretation and application of the defense process accounting standards as a result that suggests that maintained a conservative stance. Second, working between career and accruals negative (-) the relevance of the observed. This work experience is further the professional degree for a conservative accounting approach and attitude to accounting because of high and this can be interpreted as a factor that may act to increase the quality of accounting information. The result of this study is to provide policy implications for the workforce of the group financial footing and treasurer for the organization and enhance the usability of accounting information defense. 본 연구의 목적은 군 조직의 특성과 회계담당자의 특성이 국방회계정보의 품질에 미치는 영향을 분석하는데 있다. 본 연구는 국방회계 재무제표를 생산하는 육・해・공 단위부대급을 대상으로 발생주의・복식부기 회계제도를 도입한 2009년부터 2014년까지 6년 동안의 표본 604개를 분석했다. 군 조직특성과 발생액 사이 관련성을 분석한 결과는 다음과 같다. 첫째, 부대규모와 총발생액 사이 유의한 음(-)의 관련성이 있음을 발견했다. 이는 부대규모가 클수록 정치비용가설에 따라 회계정보의 품질이 높아질 수 있음을 시사한다. 둘째, 복지회관을 보유한 경우 상대적으로 발생액의 크기가 증가함을 밝혔다. 이는 기업회계기준을 적용하는 복지회관을 보유한 부대일수록 이를 활용하여 발생액을 증가시킬 수 있어 상대적으로 회계정보의 품질이 낮아질 수 있음을 의미한다. 다음으로 군 회계담당자의 특성과 발생액 사이 관련성을 분석한 결과는 다음과 같다. 첫째, 재정병과 간부의 최고계급이 높은 부대일수록 발생액의 크기가 상대적으로 작아지는 현상이 관찰되었다. 계급이 높을수록 회계업무의 전문성이 높아 국방회계기준의 적용과 해석과정에서 보수주의적 입장을 견지한다는 것을 시사하는 결과로 판단된다. 둘째, 근무경력과 발생액간에 음(-)의 관련성이 관찰되었다. 이는 근무경력이 길수록 회계업무에 대한 전문성 정도가 높기 때문에 회계처리 등에 대해 보수주의적 태도로 접근하고 이는 회계정보의 질을 높이는 요인으로 작용할 수 있다는 것으로 해석할 수 있다. 이러한 연구의 결과는 국방회계정보의 유용성을 높이기 위한 군 회계조직 및 회계담당자에 대한 편제와 인력운영에 관한 정책적 시사점을 제공하고 있다.

Feasibility of Photon-counting K-edge Imaging in X-ray and Computed Tomographic Systems: Monte Carlo Simulation Studies

이승완,김희중,최유나,조효민,이영진,류현주 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.4

Conventional X-ray systems and X-ray computed tomography (CT) systems, which use detectors operated in the integrating mode, are not able to reflect spectral information because the detector output is proportional to the energy fluence integrated over the whole spectrum. Photon-counting detectors have been considered as alternative devices. These detectors can measure the photon energy deposited by each event and improve the image quality. In this study, we investigated the feasibility of K-edge imaging using a photon-counting detector and evaluated the capability of material decomposition in X-ray images. The geometries of X-ray imaging systems equipped with cadmium telluride (CdTe) detectors and phantoms consisting of different materials were designed using Geant4 Application for Tomographic Emission (GATE) version 6.0. To observe the effect of a discontinuity in the attenuation due to the K-edge of a high atomic number material, we chose the energy windows to be one below and one above the K-edge absorption energy of the target material. The contrast-to-noise ratios (CNRs) of the target materials were increased at selective energy levels above the K-edge absorption energy because the attenuation is more dramatically increased at energies above the K-edge absorption energy of the material than at energies below that. The CNRs for the target materials in the K-edge image were proportional to the material concentration. The results of this study show that K-edge imaging can be carried out in conventional X-ray systems and X-ray CT systems using CdTe photon-counting detectors and that the target materials can be separated from background materials by using K-edge imaging. The photon-counting detector has potential to provide improved image quality, and this study will be used as a basis for future studies on photon-counting X-ray imaging.

COVID-19 확산방지를 위한 보육시설, 집단급식소 및 식품접객업소 생활방역 매뉴얼 개발

이승완,장혜자,한아름,이선영,김성일,반경녀,Lee, Seung-Wan,Chang, Hye-Ja,Han, Areum,Lee, Sun-Young,Kim, Sung-Il,Bahn, Kyeong-Nyeo 한국급식외식위생학회 2020 급식외식위생학회지 Vol.1 No.1

The virus isolated from patients with severe pneumonia of unknown etiology in Wuhan City, Hubei province in China was termed SARS-CoV-2 and the World Health Organization (WHO) named the disease caused by this virus as coronavirus disease 2019 (COVID-19). The COVID-19 infection has spread rapidly and become a pandemic. In July 2020, there were 13.25 million infected patients and over 570,000 deaths worldwide, and 13,711 infected patients and 294 deaths were reported in South Korea. Since the primary mode of transmission of COVID-19 is through respiratory droplets, the importance of preventive measures, including social distancing, has become important in daily life. In response to the continuous spread of COVID-19, this study developed three guidelines for preventing COVID-19 for the food service industry including childcare centers, institutional foodservices and restaurants by the integration of the manual of controlling foodborne illness. These are included the COVID-19 prevention action methods for food deliverers, for food service administrator, for foodservice works and for customers. All guidelines were designed for easy understanding using illustrations and have been systematically explained subject wise. Thus, these COVID-19 prevention guidelines can be appropriately applied depending on the specific situation and workplace. In addition, they are worthy as educational materials that contribute to the food safety.

Wavelet 변환과 결합한 잔차 학습을 이용한 희박뷰 전산화단층영상의 인공물 감소

이승완 한국방사선학회 2022 한국방사선학회 논문지 Vol.16 No.3

Sparse-view computed tomography (CT) imaging technique is able to reduce radiation dose, ensure the uniformity of image characteristics among projections and suppress noise. However, the reconstructed images obtained by the sparse-view CT imaging technique suffer from severe artifacts, resulting in the distortion of image quality and internal structures. In this study, we proposed a convolutional neural network (CNN) with wavelet transformation and residual learning for reducing artifacts in sparse-view CT image, and the performance of the trained model was quantitatively analyzed. The CNN consisted of wavelet transformation, convolutional and inverse wavelet transformation layers, and input and output images were configured as sparse-view CT images and residual images, respectively. For training the CNN, the loss function was calculated by using mean squared error (MSE), and the Adam function was used as an optimizer. Result images were obtained by subtracting the residual images, which were predicted by the trained model, from sparse-view CT images. The quantitative accuracy of the result images were measured in terms of peak signal-to-noise ratio (PSNR) and structural similarity (SSIM). The results showed that the trained model is able to improve the spatial resolution of the result images as well as reduce artifacts in sparse-view CT images effectively. Also, the trained model increased the PSNR and SSIM by 8.18% and 19.71% in comparison to the imaging model trained without wavelet transformation and residual learning, respectively. Therefore, the imaging model proposed in this study can restore the image quality of sparse-view CT image by reducing artifacts, improving spatial resolution and quantitative accuracy. 희박뷰 전산화단층촬영(computed tomography; CT) 영상화 기술은 피폭 방사선량을 감소시킬 수 있을 뿐만 아니라 획득한 투영상의 균일성을 유지하고 잡음을 감소시킬 수 있는 장점이 있다. 하지만 재구성 영상 내 인공물 발생으로 인하여 화질 및 피사체 구조가 왜곡되는 단점이 있다. 본 연구에서는 희박뷰 CT 영상의 인공물 감소를 위해 wavelet 변환과 잔차 학습(residual learning)을 적용한 콘볼루션 신경망(convolutional neural network; CNN) 기반 영상화 모델을 개발하고, 개발한 모델을 통한 희박뷰 CT 영상의 인공물 감소 정도를 정량적으로 분석하였다. CNN은 wavelet 변환 층, 콘볼루션 층 및 역 wavelet 변환 층으로 구성하였으며, 희박뷰 CT 영상과 잔차 영상을 각각 입출력 영상으로 설정하여 영상화 모델 학습을 진행하였다. 영상화 모델 학습을 위해 평균제곱오차(mean squared error; MSE)를 손실함수로, Adam 함수를 최적화 함수로 사용하였다. 학습된 모델을 통해 입력 희박뷰 CT 영상에 대한 예측 잔차 영상을 획득하고, 두 영상간의 감산을 통해 최종 결과 영상을 획득하였다. 또한 최종 결과 영상에 대한 시각적 특성, 최대신호대잡음비(peak signal-to- noise ratio; PSNR) 및 구조적유사성지수(structural similarity; SSIM)를 측정하였다. 연구결과 본 연구에서 개발한 영상화 모델을 통해 희박뷰 CT 영상의 인공물이 효과적으로 제거되며, 공간분해능이 향상되는 결과를 확인하였다. 또한 wavelet 변환과 잔차 학습을 미적용한 영상화 모델에 비해 본 연구에서 개발한 영상화 모델은 결과 영상의 PSNR 및 SSIM을 각각 8.18% 및 19.71% 향상시킬 수 있음을 확인하였다. 따라서 본 연구에서 개발한 영상화 모델을 이용하여 희박뷰 CT 영상의 인공물 제거는 물론 공간분해능 향상 및 정량적 정확도 향상 효과를 획득할 수 있다.

RFID기반의 POS시스템 개발 및 적용에 관한 연구

이승완,백민열,신수호,김창훈,오민석 대한산업공학회 2011 대한산업공학회 추계학술대회논문집 Vol.2011 No.11

국내·외 프로폴리스 산업 동향

이승완 한국양봉학회 2015 한국양봉학회 학술대회 자료집 Vol.2015 No.3

조직규모, 회계인력, 회계환경 특성이 국방회계정보의 유용성에 미치는 영향

이승완,윤병섭 한국회계정보학회 2017 회계정보연구 Vol.35 No.1

본 연구는 국방부 산하 육군·해군·공군의 예하 단위부대에서 산출한 재무제표상의 회계정보를 활용하여 조직규모, 회계인력, 회계환경 특성이 국방회계정보의 품질을 대용하는 총발생액과 비배분원가에 미치는 영향을 분석하였다. 2009년부터 2014년까지 6년 동안 국방회계 재무제표를 생산하는 육군·해군·공군의 단위부대급 총표본 604부대-연도를 분석하였다. 본 연구 결과는 다음과 같다. 첫째, 군 조직규모의 특성을 부대의 자산규모와 자산성장성으로 구분하여 분석한 결과, 부대 자산규모가 클수록 총발생액이 감소하였으며, 비배분원가의 크기가 감소하고 있음을 발견하였다. 이러한 결과는 부대규모가 클수록 정치비용효과가 크게 작용하고 세부적이고 정교한 원가배분기준을 마련해 적용하는 것으로 여겨진다. 둘째, 군 회계업무를 담당하는 재정병과 간부의 특성은 회계정보의 품질이나 유용성 등에 영향을 미치는 것으로 나타났다. 재정병과 간부의 계급이 높을수록 군 회계업무 경력이나 전문성이 높아 보수주의적 입장에서 회계처리를 하고 공통원가 배분기준을 마련한다고 판단된다. 셋째, 부대 내 참모부별 회계정보 활용수준이 높을수록 보수적 태도를 견지해 회계처리 하고 있음을 발견하였다. 이는 해당 참모부가 정교하고 세분화한 원가배분기준을 마련해 적용할 가능성이 높고 비배분원가 비중을 낮추는 것으로 보인다. 본 연구의 정책적 시사점은 다음과 같다. 첫째, 군 회계정보의 품질을 유지하거나 개선할 수 있는 제도적 장치를 마련함이 필요하다. 회계업무담당자의 회계처리에 따라 재정운영이나 재정상태가 달라짐은 그 만큼 회계정보의 안정성이나 품질의 신뢰성을 훼손할 수 있기 때문에 합리적 회계처리가 이루어질 수 있도록 지침이나 가이드라인과 같은 제도적 장치를 마련해야 한다. 둘째, 정교하고 세분화한 군 원가배분기준을 합리적이고 타당성 있게 마련할 필요가 있다. 소비집단이라고 할 수 있는 국방조직은 수익보다 비용이나 원가 중심의 재무제표를 산출한다. 직접원가보다 공통원가(또는 결합원가)의 비중이 높으면 정교하고 세분화한 원가배분기준을 마련하여 원가분석이나 비용분석에 필요한 신뢰성 있는 자료를 제공해야 한다. 이를 통해 성과중심의 효율적 예산편성을 가능하게 해야 한다. 셋째, 발생주의·복식부기 국방회계를 도입한 이후 군은 각 자원관리부대의 운영성과와 재정상태에 관한 정보를 산출하고 있다. 이러한 회계정보는 부대 운영에 필요한 경제적 의사결정과정에 활용하지만 회계정보의 활용도가 기대만큼 크지 않은 게 현실이다. 따라서 고품질의 회계정보를 활용한 부대 운영의 사례를 발굴하고 이에 대한 가이드라인을 제시할 필요가 있다. 넷째, 국방 회계업무를 담당하고 있는 재정병과 병력들이 발생주의·복식부기 회계정보를 산출하고 있다. 재정병과 병력들을 지휘하는 각급부대 지휘관이 회계정보 이해력을 높일 수 있는 방안을 모색할 필요가 있다. 군 조직의 운영에 회계정보를 활용하기 위해서는 보병, 포병, 기갑 등 전투병과 간부들이 회계정보를 이해할 수 있도록 각종 보수교육과정에 회계교과목을 편성할 필요성이 있다. The purpose of this study is to investigate the effects of organizational size, accounting manpower, accounting environment, etc. on the total accruals and non-allocation cost, which substitute the quality of defense accounting information, by using the accounting information on financial statements calculated by the units of the army, navy and air force. A total of 604 units at each level of the army, navy, and air force, which produce the financial accounting statements from 2009 to 2014, were analyzed on a year-on-year basis. The results of this study are as follows. First, as a result of analyzing the characteristics of military organization size by asset size and asset growth ability of the unit, the larger the size of the unit’s asset is, the smaller the total accruals are and the less the non-allocation cost is. These results suggest that the larger the size of the unit is, the greater the effect of the political cost is and the more detailed and sophisticated cost allocation criteria are applied. Second, the characteristics of the cadres in the financial branch in charge of military accounting affect the quality and usefulness of accounting information. The higher the rank of fiscal officers is, the higher the experience and expertise in the military accounting business are. Therefore, it can be interpreted as accounting for relatively conservative stance and applying cost allocation criteria for common costs. The number of commanders in fiscal is similar to the results of the variables in the highest class. Third, I found that the higher the level of utilization of accounting information by staff is, the more conservative attitude is maintained to process accounting. This implies that the staffs are more likely to apply more sophisticated and detailed cost allocation criteria and reduce the proportion of non-allocation costs. The political implications of this study are as follows. First, it is necessary to establish an institutional device to maintain or improve the quality of military accounting information. The fact that the financial management and the financial status are changed according to the accounting process of the accounting staff in charge can cause the reliability of the accounting information to be deteriorated in terms of stability and quality. Therefore, institutional arrangements such as guidelines should be made so that institutionally conservative accounting can be done. Second, it is required to establish elaborate and detailed cost allocation standards for military cost accounting system. Defense organization, so-called consumer group, produces financial statements based on expense or production cost rather than revenue. Especially, since the share of common cost . or combined cost) is higher than direct cost, rational and valid allocation standards should be made, so reliable data should be calculated for production cost analysis and expense analysis. This will enable effective compilation of budget oriented performance. Third, since the accrual basis of accounting and double-entry bookkeeping were introduced, information about operation result and financial condition of each unit has been produced. These accounting information are used in the economic decision making process required for the unit operation, but the utilization of accounting information is not as large as expected. Therefore, it is necessary to develop a case study on the use of accounting information and to provide guidelines for it. Fourth, the military forces in charge of defense accounting are calculating the accrual basis of accounting and double-entry bookkeeping information, so it is necessary to seek ways to improve the understanding of these accounting information by unit commanders at each level. In order to utilize accounting information in the operation of military organizations, it is necessary to organize accounting courses in various curriculums such as infantry, artillery, armor, etc. to enable sold...

API X70 라인파이프강의 인장 특성에 미치는 변형 시효의 영향

이승완,이상인,황병철,Lee, Seung-Wan,Lee, Sang-In,Hwang, Byoungchul 한국재료학회 2017 한국재료학회지 Vol.27 No.10

The effect of strain aging on the tensile properties of API X70 linepipe steel was investigated in this study. The API X70 linepipe steel was fabricated by controlled rolling and accelerated cooling processes, and the microstructure was analyzed using optical and scanning electron microscopes and electron backscatter diffraction. Strain aging tests consisting of 1 % pre-strain and thermal aging at $200^{\circ}C$ and $250^{\circ}C$ were conducted to simulate U-forming, O-forming, Expansion(UOE) pipe forming and anti-corrosion coating processes. The API X70 linepipe steel was composed of polygonal ferrite, acicular ferrite, granular bainite, and bainitic ferrite whose volume fraction was dependent on the chemical composition and process conditions. As the thermal aging temperature increased, the steel specimens showed more clearly discontinuous type yielding behavior in the tensile stress-strain curve due to the formation of a Cottrell atmosphere. After pre-strain and thermal aging, the yield and tensile strengths increased and the yield-to-tensile strength ratio decreased because yielding and aging behaviors significantly affected work hardening. On the other hand, uniform and total elongations decreased after pre-strain and thermal aging since dislocation gliding was restricted by increased dislocation density after a 1 % pre-strain.

API X70 라인파이프 강재의 변형 시효 특성에 미치는 미세조직의 영향

이승완,임인혁,황병철,Lee, Seung-Wan,Im, In-Hyuk,Hwang, Byoungchul 한국재료학회 2018 한국재료학회지 Vol.28 No.12

This study deals with the effect of microstructure factors on the strain aging properties of API X70 pipeline steels with different microstructure fractions and grain sizes. The grain size and microstructure fraction of the API pipeline steels are analyzed by optical and scanning electron microscopy and electron backscatter diffraction analysis. Tensile tests before and after 1 % pre-strain and thermal aging treatment are conducted to simulate pipe forming and coating processes. All the steels are composed mostly of polygonal ferrite, acicular ferrite, granular bainite, and bainitic ferrite. After 1 % pre-strain and thermal aging treatment, the tensile test results reveal that yield strength, tensile strength and yield ratio increase, while uniform elongation decreases with an increasing thermal aging temperature. The increment of yield and tensile strengths are affected by the fraction of bainitic ferrite with high dislocation density because the mobility of dislocations is inhibited by interaction between interstitial atoms and dislocations in bainitic ferrite. On the other hand, the variation of yield ratio and uniform elongation is the smallest in the steel with the largest grain size because of the decrease in the grain boundary area for dislocation pile-ups and the presence of many dislocations inside large grains after 1 % pre-strain.