• 한국컴퓨터정보학회논문지
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• 제15권2호
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• pp.171-178
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• 2010

본 연구는 중소기업의 정보화를 추진함에 있어, 정보화 중에서도 중단기적인 도입 성과를 낼 수 있는 생산설비정보화 구축을 위하여, 성형제조업 분야의 생산실적 수집에 대한 표준 모델을 연구 개발한다. 성형제조업 생산설비정보화 표준화를 위한 개발방법론은 기 연구 개발된 생산설비정보화 개발 방법론(PSDM)을 적용하며, 표준화 모델은 생산관리 프로세스 중 메인 프로세스인 원자재수급 관리와 생산량 집계 2개의 프로세스를 표준화 시키고 표준 모듈을 개발한다. 본 연구로 생산설비정보화를 구축하고자 하는 성형제조업 중소기업 및 관련 전문 IT업체 들이 표준화된 모듈을 적용하여 시스템을 보다 효과적으로 구축 할 수 있으며, 시스템에 대한 구축 용이성과 신뢰성을 제공한다. 본 연구 결과를 적용함으로써 생산공정의 불합리한 요소제거, 생산제품 품질 향상, 생산비용절감이 가능하다.

• 산업경영시스템학회지
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• 제43권1호
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• pp.26-33
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• 2020

The plastic waste problem is deepening all over the world. Plastic wastes have serious impacts on our lives as well as environ- mental pollution. The production and use of plastics increases every year, but once they are produced, they usually roam the earth for hundreds or thousands of years to pollute the environment. Although there is growing interest in plastic issues around the world and environmental regulations are being tightened, but no clear solution has yet been found. This study suggests Environmental degradation index (EDI). EDI can help raise consumers' attention to plastic wastes. In addition, EDI will contribute to reduce them in the future. As far as we know, this is the first study. We developed EDI for the confectionery packaging. This study defines four factors that may affect the environment of confectionery packaging: greenhouse gas emissions, energy consumption, methane emissions, and packaging space ratio. Then we quantify the value of each element and compute EDI as the sum of the four component values. In order to evaluate the feasibility of EDI proposed in this study, confectionery-packaging materials distributed in Korea were collected and analyzed. First, the types of confectionery are classified into pies, biscuits, and snacks and basic data was collected. Then the values of the four components were calculated using existing research data on the environment. We can use the proposed EDI to determine how much a product packing affects the environment.

• 한국경영과학회지
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• 제31권1호
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• pp.91-103
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• 2006

Given a bill of materials (BOM) tree T labeled by the breadth first search (BFS) order from node 0 to node n and a general network ${\Im}=(V,A)$, where V={1,2,...,m} is the set of production facilities and A is the set of arcs representing transportation links between any of two facilities, we assume that each node of T stands for not only a component. but also a production stage which is a possible stocking point and operates under a periodic review base-stock policy, We also assume that the random demand which can be achieved by a suitable service level only occurs at the root node 0 of T and has a normal distribution $N({\mu},{\sigma}^2)$. Then our integrated model of facility location problems and safety stock optimization problem (FLP&SSOP) is to identify both the facility locations at which partitioned subtrees of T are produced and the optimal assignment of safety stocks so that the sum of production cost, inventory holding cost, and transportation cost is minimized while meeting the pre-specified service level for the final product. In this paper, we first formulate (FLP&SSOP) as a nonlinear integer programming model and show that it can be reformulated as a 0-1 linear integer programming model with an exponential number of decision variables. We then show that the linear programming relaxation of the reformulated model has an integrality property which guarantees that it can be optimally solved by a column generation method.

• 수산경영론집
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• 제46권3호
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• pp.143-161
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• 2015

This study presents a comparative analysis on mackerel distribution process and price formation process, and investigation of price and margin between traditional markets and Large-scale discount store distribution channel. Through this, the study investigated distribution efficiency of each channel, and examined whether a difference of distribution efficiency leads to a difference of performance through the investigation of a difference of function and role between members of a wholesale market and vendor of Large scale discount store. The following are the results of this study. As a consequence of investigating supply and sum by distribution channel of mackerel, it appeared that mackerels shipped from port market are distributed into 9 consumption sites(Wholesale market, Large scale discount store, Institutional Food Service, etc.). In the comparison of distribution efficiency between traditional retail store and Large scale discount store 52.0% margin is formed in traditional retail store distribution channel and 43.1% margin is formed in Large scale discount store, and a distribution cost rate consists of 19.4% cost in a traditional retail store for fishery products and 18.1% cost in a Large-scale discount store. To analyze a difference of performance, the study examine a difference of role and function between vendor and Wholesale market company, wholesaler and middleman. Wholesale market company and middleman of wholesale market for consumer have slightly high or similar score in collection function, sorting function, evaluation function and financial function which are traditional and original. However, it was confirmed that vendor has a better score in other functions, that is, newly-demanded functions(ex : market frontier function, product development function, Integral Distribution Function, etc.).

• 산업경영시스템학회지
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• 제38권3호
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• pp.159-168
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• 2015

Aggregate Production Planning determines levels of production, human resources, inventory to maximize company's profits and fulfill customer's demands based on demand forecasts. Since performance of aggregate production planning heavily depends on accuracy of given forecasting demands, choosing an accurate forecasting method should be antecedent for achieving a good aggregate production planning. Generally, typical forecasting error metrics such as MSE (Mean Squared Error), MAD (Mean Absolute Deviation), MAPE (Mean Absolute Percentage Error), and CFE (Cumulated Forecast Error) are utilized to choose a proper forecasting method for an aggregate production planning. However, these metrics are designed only to measure a difference between real and forecast demands and they are not able to consider any results such as increasing cost or decreasing profit caused by forecasting error. Consequently, the traditional metrics fail to give enough explanation to select a good forecasting method in aggregate production planning. To overcome this limitation of typical metrics for forecasting method this study suggests a new metric, WACFE (Weighted Absolute and Cumulative Forecast Error), to evaluate forecasting methods. Basically, the WACFE is designed to consider not only forecasting errors but also costs which the errors might cause in for Aggregate Production Planning. The WACFE is a product sum of cumulative forecasting error and weight factors for backorder and inventory costs. We demonstrate the effectiveness of the proposed metric by conducting intensive experiments with demand data sets from M3-competition. Finally, we showed that the WACFE provides a higher correlation with the total cost than other metrics and, consequently, is a better performance in selection of forecasting methods for aggregate production planning.

• 대한안전경영과학회지
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• 제16권2호
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• pp.217-230
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• 2014

The purpose of this study is to develop the Generalized Depreciation Function (GDF) and Winfrey Depreciation Function (WDF) by reviewing methods for the depreciation accountings. The Depreciation Accounting Models (DAM), including straight-line model, declining-balance model, sum-of-the-year-digit model and sinking fund model presented in this paper, are reclassified into the charging pattern of increasing type, decreasing type and constant type. This paper also discusses the development of the GDFs based on convex type, concave type and constant type according to the demand pattern of product, frequency of plant usage, deterioration of time, relative inadequacy, Capital Expenditure (CAPEX) and Operating Expenditure (OPEX) of the Total Productive Maintenance (TPM). The WDFs presented in this paper depict a sudden degradation of plant performance by measuring the change of TPM activity at the midpoint of useful life of asset. The WDFs are classified into left-modal type, symmetrical type and right-modal type by varying the value of skewness and kurtosis. Moreover, three increasing patterns, such as convex, concave and linear types, are used in this paper to present the distinct identification of WFDs by using Instantaneous Depreciation Rate (IDR) in terms of Performance Depreciation Function (PDF) and Depreciation Density Function (DDF). In order to have better understanding of depreciation models, the numerical examples are used for evaluating the Net Operating Less Adjusted Tax (NOPLAT) and Economic Value Added (EVA). It is concluded that the depreciation models showing a large dispersion of EVA require the adjustment of NOPLAT and Invested Capital (IC) based on the objective cash basis and net operating activity for reducing the variation of EVA.

• 한국음향학회지
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• 제16권2호
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• pp.71-79
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• 1997

본 논문에서는 FVQ-DHMM(fuzzy vector quantization-discrete hidden Markov model)에서 강인한 출력확률의 추정을 위해서 코드워드 종속 거리 정규화와 출력확률에 대한 instar 형태의 퍼지 평활화 방법을 제안한다. FVQ-DHMM은 DHMM의 변형된 모델로, 상태별 출력확률이 입력패턴에 대한 각 코드워드와의 가중치와 출력확률의 곱에 대한 합의 형태로 추정된다. FVQ-DHMM의 성능이 가중치 요소와 상태별 출력분포에 영향을 받으므로, 가중치 요소와 상태별 출력분포를 강인하게 추정하는 방법이 필요하게 된다. 실험결과, 제안된 코드워드 종속 거리 정규화(CDDN : codeword dependent distance normalization)를 적용한 방법이 기존의 FVQ-DHMM에 비해 24%의 오인식률 감소가 있었으며, 상태별 출력분포에 대해서 평활화를 적용한 경우 79%의 오식율을 감소 시킴을 알 수 있었다. 이러한 결과는 제안된 CDDN과 퍼지 평활화의 사용이 향상된 인식율을 얻는데 주요하며, 결과적으로 제안된 방법이 FVQ-HMM을 위한 강인한 출력확률의 추정을 위한 대안으로 유용함을 보여준다고 할 수 있다.

• 한국농공학회논문집
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• 제63권6호
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• pp.61-75
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• 2021

This study aims to assess the changes in crop water requirement of paddy and upland according to future climate and land use changes scenarios. Changes in the spatiotemporal distribution of temperature and precipitation are factors that lower the stability of agricultural water supply, and predicting the changes in crop water requirement in consideration of climate change can prevent the waste of limited water resources. Meanwhile, due to the recent changes in the agricultural product consumption structure, the area of paddy and upland has been changing, and it is necessary to consider future land use changes in establishing an appropriate water use plan. Climate change scenarios were derived from the four GCMs of the CMIP6, and climate data were extracted under two future scenarios, namely SSP1-2.6 and SSP5-8.5. Future land use changes were predicted using the FLUS (Future Land Use Simulation) model. Crop water requirement in paddy was calculated as the sum of evapotranspiration and infiltration based on the water balance in a paddy field, and crop water requirement in upland was estimated as the evapotranspiration value by applying Penman-Monteith method. It was found that the crop water requirement for both paddy and upland increased as we go to the far future, and the degree of increase and variability by time showed different results for each GCM. The results derived from this study can be used as basic data to develop sustainable water resource management techniques considering future watershed environmental changes.

• 한국환경농학회지
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• 제40권2호
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• pp.142-147
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• 2021

BACKGROUND: Agricultural use and pest control purposes of pesticides may lead to livestock products contamination. Thiodicarb and its degraded product, methomyl, are carbamate insecticides that protect soya bean, maize, fruit, and vegetables and control flies in animal and poultry farms. For maximum residue limit enforcement and monitoring, the JMPR residue definition of thiodicarb in animal products is the sum of thiodicarb and methomyl, expressed as methomyl. This residue definition was set to consider the fact that thiodicarb was readily degraded to methomyl in animal commodities. And therefore the simultaneous analytical method of thiodicarb and methomyl is required for monitoring in livestock products. METHODS AND RESULTS: The study was conducted using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and HPLC-MS/MS to determine the thiodicarb and methomyl in livestock products. The limit of quantitation (LOQ) was 0.01 mg/kg for livestock products, including beef, pork, chicken, milk, and egg. The coefficient of determinations (r²) for the calibration curve were > 0.99, which was acceptable values for linearity. Average recoveries at spiked levels (LOQ, 10LOQ, and 50LOQ, n=5) in triplicate ranged from 73.2% to 102.1% and relative standard deviations (RSDs) were less than 10% in all matrices. CONCLUSION: The analytical method was validated for the performance parameters (specificity, linearity, accuracy, and precision) in livestock products to be acceptable by the CODEX guidelines.

• 한국약용작물학회지
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• 제28권6호
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• pp.445-454
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• 2020

Background: Culturing wild ginseng adventitious root using plant factory technology provides genetic safety and high productivity. This production technology is drawing attention in the fields of functional raw materials and product development. The cultivation method using elicitors is key technology for controlling biomass and increasing secondary metabolites. Methods and Results: Elicitor treatments using methyl jasmonate, pyruvic acid, squalene, β-sistosterol were performed to amplify total ginsenosides (Rb1, Rc, Rb2, Rb3, and Rd) of cultured wild ginseng adventitious root. Thereafter, fermentation and steaming processes were performed to convert total ginsenosides into minor molecular ginsenosides (Rg3, Rk1, and Rg5). The result indicated that methyl jasmonate minimizes the reduction in fresh weight of cultured wild ginseng adventitious root and maximizes total ginsenosides (sum of Rb1, Rc, Rb2, Rb3, and Rd). Ginsenoside conversion results showed a maximum degree of conversion of 131 mg/g. Conclusions: In this study, we demonstrated that the optimal elicitor treatment method increased the content of total ginsenosides, while the steaming and fermentation processing method increased the content of minor ginsenosides.