An austenitic stainless steel canister functions as a containment barrier for spent nuclear fuel and radioactive materials. The canister on the spent fuel storage system near the coastal area has several welding lines in the wall and lid, which have high residual tensile stresses after welding procedure. Interaction between austenitic stainless steel and chloride environment from a sea forms a detrimental condition causing chloride induced stress corrosion cracking (CISCC) in the canister. The South Korea is concerned with the dry storage of high-level spent nuclear fuel and radioactive wastes to be built on the site of a nuclear power plant. The importance of aging management has recently emerged for mitigating CISCC of dry storage canisters. When a corrosive pit is created by a localized corrosion in a sea water atmosphere, it initiates and grows as CISCC crack. Surface stress improvement works by inducing plastic strain which results in elastic relaxation that generates residual compressive stress. Surface stress improvement methods such as roller burnishing process can effectively mitigate the potential for CISCC of the canister external surfaces. The generation of compressive stress layer can inhibit the transition to cracking initiation. In this study, a flat roller burnishing process was applied as a prevention technology to CISCC of stainless steel canisters. Roller burnishing process parameters have been selected for 1:3 scale canister model having a diameter of 600 mm, a length of 1,000 mm and a thickness of 10 mm on the basis of the burnishing conditions available to control residual tensile stress of austenitic stainless steel plate specimens. The surface roughness of the scaled canister model was investigated using a surface roughness measurement equipment after roller burnishing treatment. The surface residual stresses of the scaled canister model were measured by a hole drilling contour method attached with strain gauge. The burnishing test results showed that the surface roughness of the scaled canister model was considerably improved with flat rollers having the tip width of 4 mm. The surface of the scaled canister model had significant residual compressive stress after burnishing treatment. The roller burnished canister with good surface roughness could reduce the number of crack initiation sites and the residual compressive stress formed on the welded surface might prevent the crack initiation by reducing tensile residual stress in the weld zone, finally leads to CISCC resistance.

In this study, a model was developed to predict for Disinfection By-Products (DBPs) generated in water supply networks and consumer premises, before and after the introduction of advanced water purification facilities. Based on two-way ANOVA, which was carried out to statistically verify the water quality difference in the water supply network according to introduce the advanced water treatment process. The water quality before and after advanced water purification was shown to have a statistically significant difference. A multiple regression model was developed to predict the concentration of DBPs in consumer premises before and after the introduction of advanced water purification facilities. The prediction model developed for the concentration of DBPs accurately simulated the actual measurements, as its coefficients of correlation with the actual measurements were all 0.88 or higher. In addition, the prediction for the period not used in the model development to verify the developed model also showed coefficients of correlation with the actual measurements of 0.96 or higher. As the prediction model developed in this study has an advantage in that the variables that compose the model are relatively simple when compared with those of models developed in previous studies, it is considered highly usable for further study and field application. The methodology proposed in this study and the study findings can be used to meet the level of consumer requirement related to DBPs and to analyze and set the service level when establishing a master plan for development of water supply, and a water supply facility asset management plan.

The spotted wing drosophila (SWD), Drosophila suzukii, is classified exotic quarantine pest in Australia and EU, soSWD-free must be supported by evidence of surveys and phytosanitary measures in exported host agricultural commoditiesin Korea. From a quarantine control point of view, SWD is importantly considered as model insect pest for exotic fruitflies (Bactrocera dorsalis) in Korea as well because of similarity in ecological cycles. In evaluations of ethyl formate(EF) only and combined cold treatment to kill eggs and larvae of SWD, the combined EF fumigation applied at LCt50%(50% killed lethal concentration X time) and cold treatement (5℃) for > 5 days showed the promise to new conceptfor eradicating quarantine pest and these could be helpful to pre-develop exotic fruit fly management in Korea.

This paper deals with the application of Supply Chain Operations Reference (SCOR) model to make a Service Supply Chain(sSC) of a hospital treatment service. At first, we compare the service supply chain with the traditional supply chain. At second, we app

This study deals with what is the best treatment model against offenders refer to punitive purpose, criminal cause theory, responsibility principle of criminal law and korean criminal policy etc. Because one kind of treatment model against offenders are not appropriate to view point of various the punitive purpose theories and the criminal cause theories, this study was focused on the view that a few treatment model against offenders should be combined. And it is necessary the viewpoint that each treatment models against offenders can mutually realize supplementary function. In conclusion, this study included that the combined treatment model against offenders(combined model of rehabilitation model, reintegration model and justice model) was the best model theory in treatment model against offenders. this model combined partial factors of followed three models ; -. This model fundamentally is based on the rehabilitation model. -. The excessive criminal punishment problem should be restricted by application of responsibility principle of criminal law.(justice model's factor) -. Because the nation and society produced a part of criminal cause, they correspondingly must be responsible for the criminal cause. (reintegration model's factor). Because of this reason, they have duty to make healthy social environment.

A sundry system is one of popular systems for composting livestock manure, of which main honest is to utilize unlimited, clean, and free solar radiation. A sundry system with a composter of two horizontal screw-type concrete ducts at different height, was constructed and operated for three days for each test in May, 1993, to evaluate its composting performance. Four treatments of the mixture ratio of swine manure and saw dust (manure : sawdust= 1 : 1.25, 1 : 1, 1 : 0.7, 1 : 0.5) were implemented to evaluate the effect of the mixture ratio on degradation of the composting materials of a sundry system with a screw-type composter. Maximum temperature of the composting materials was over 50℃ at D1 or D2 (one or two days after operation starts) for each test. Mean C/N ratio and water contents of the materials were reduced by more than 15 and 20％, respectively. Microbial density of each test showed a typical variation with the lapse of the composting time. Mesophilic microorganism seemed to play more important role on degradation of the materials than thermophilic. A sundry system with a screw-type composter can be considered as a feasible system on basis of maturity data. The conclusion was completely reverse from that of Choi et at., although both adopted a sundry system. A further study is recommended to pursue the cause of better performance of the screw-type composter, whether it was due to affirmative weather or more efficient composter.

This article analyzes the structural characteristics and working principles of heat treatment equipment while considering the possibility of “zero-carbon manufacturing.” It integrates the concepts of material flow, energy flow, and waste recycling, and, by following the life cycle theory, constructs a system boundary model for heat treatment equipment to track the direction of carbon emissions throughout various stages. It identifies the sources and forms of carbon emissions in the entire process of heat treatment equipment and proposes carbon emission estimation models for each stage, upon which a comprehensive data inventory for heat treatment equipment is established.

In this study, an operational data set was analysed by establishing a path model to figure out the actual cause-effect relationship of a wastewater treatment plant (WWTP); in particular, for the effluent concentrations of T-N and T-P. To develop the path models, data sets of operational records including effluent concentrations and operational factors were obtained from a field scale WWTP of 680,000 m3 of treatment capacity. The models showed that the relationship networks with the correlation coefficients between variables for objective expressions indicated the strength of each relationship. The suggested path models were verified according to whether the analyzation results matched known theories well, but sophisticated minute theoric relationships could not be cropped out distinctly. This indicates that only a few paths with strong theoric casual relationships were represented as measured data due to the high non-linearity of the mechanism of the removal process in a biological wastewater treatment.

Nonylphenols (NP) are used in manufacturing antioxidants and lubricating oil additives, which are considered to be as potent endocrine disruptor. The aim of this study was to examine the effects of NP on reproductive system in adult male mice. Mice were divided into 4 groups; (1) tap water (CON group), (2) 50 μg/L (NP50), (3) 500 μg/L (NP500) and (4) 5000 μg/L (NP5000) of NP via the drinking water for 4 weeks. Mice were sacrificed and the reproductive organ weights were measured. The caudal epididymal sperms were count to assess the toxicity on germ cells. Histopathological changes of tissues were observed by using hematoxylin/eosin staining. The weights of testis in NP5000 group were significantly lighter than those in CON group (104.9±2.9 mg vs 90.7±5.1 mg, p<0.05). And weights of epididymis significantly increased in NP500 group (44.2±2.6 mg vs 54.42±3.44 mg, p<0.05). As concentration of NP increased, the number of sperms significantly decreased (NP50 and NP500, p<0.01; NP5000, p<0.001). In histopathological analyses, the sperms in seminiferous tubules showed a concentration-dependent decrease in mice treated with NP. In epididymis, treatment with NP resulted in empty space and the reduced sperm numbers in dose-dependent manner. Our results confirmed the dose-dependent decrease in the number of sperm and histopathological abnormality of testis and epididymis in mice exposed from 50 μg/L to 5000 μg/L of NP for 4 weeks. The present study suggests that oral exposure of NP might have negative effects on reproductive function, particularly on germ cells, in adult male mice.

본 연구에서는 자연하천의 흐름에서 흔히 발생하는 천이류, 불연속류, 마른하도로의 파의 전파 등을 포함하는 복잡한 흐름을 해석하기 위한 고정확도 2차원 수치모형을 개발하였다. 하상경사항을 효율적으로 처리하기 위해 quasi-steady wave propagation 기법을 적용하여 해당 격자에 대한 생성항의 영향을 효율적으로 반영함으로써 쌍곡선형 적분 보존형의 2차원 천수방정식을 해석하였다. Fractional Step Method를 적용한 유한체적기법의

본 연구에서는 지표흐름 습지의 수질관리를 위하여 습지 내 오염물질을 적절히 모의할 수 있는 연속교반탱크반응기(CSTR) 모델을 구축하였다. 이 모델은 4차 Runge-Kutta법을 사용하고, 실측치와 계산치의 차이를 최소화 하는 최적화 기법으로 해를 구하며, 미국 EPA 습지 데이터베이스에 수록된 자료중 수질 및 수리자료가 충분하며, 분석이 용이한 하나의 수생대를 갖는 습지를 선택하여, 수질항목중 관심도가 높은 BOD, TSS (Total Suspend