• KSII Transactions on Internet and Information Systems (TIIS)
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• 제18권8호
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• pp.2431-2449
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• 2024

As problems such as water pollution and fish species depletion have become serious, a land-based fish farming is receiving a great attention for ensuring stable productivity. In the fish farming, it is important to determine the timing of shipments, as one of key factors to increase net profit on the aquaculture. In this paper, we propose a system for predicting net profit to support decision of timing of shipment using fish farming-related statistical data. The prediction system consists of growth and farm-gate price prediction models, a cost statistics table, and a net profit estimation algorithm. The Gaussian process regression (GPR) model is exploited for weight prediction based on the analysis that represents the characteristics of the weight data of cultured fish under the assumption of Gaussian probability processes. Moreover, the long short-term memory (LSTM) model is applied considering the simple time series characteristics of the farm-gate price data. In the case of GPR model, it allows to cope with data missing problem of the weight data collected from the fish farm in the time and temperature domains. To solve the problem that the data acquired from the fish farm is aperiodic and small in amount, we generate the corresponding data by adopting a data augmentation method based on the Gaussian model. Finally, the estimation method for net profit is proposed by concatenating weight, price, and cost predictions. The performance of the proposed system is analyzed by applying the system to the Korean flounder data.

• Clinical and Experimental Pediatrics
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• 제50권11호
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• pp.1049-1054
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• 2007

Myocarditis represent an important condition encountered by general pediatricians & general practitioners. Its presentation is varied, and therefore a high index of suspicion must be maintained when the possibility of myocarditis is raised. A progression from viral myocarditis to dilated cardiomyopathy has long been hypothesized. Treatment is initially aimed at achieving hemodynamic stability and is largely supportive. There is currently little evidence to support the immunomodulatory or specific antiviral therapies. Pediatric cardiomyopathies are a heterogeneous group of disorders with diverse genetic, infectious, mitochodrial and metabolic etiologies. The timing and severity of presentation vary according to cardiomyopathy type as well as genetic and ethnic factors. The behavior of specific cardiomyopathies can be predicted by morphological and functional attributes, as well as underlying patient characteristics.

• 한국대기환경학회지
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• 제9권1호
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• pp.1-10
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• 1993

A brief description on the greenhouse gases, the greenhoue effect, sea level changes, forcing of climate, the history of Earth's changing climate based on the IPCC REPORT and the records of the recent variation of the climate in the Republic of Kore is presented here for help enhancing awareness of the issues. The climate of the Earth has the potential to be changed on all timescales by the fluctuations of the concentrations of radioactively active greenhouse gases, solar radiation, aerosols and albedo. However, the rate of the recent global warming seems to be larger and rapid than any have occurred thorughout recorded history enough to draw the world-wide attention and worry concerned with the theme of environment and development. There are still uncertainties in the predictions relating to the timing, magnitude and the pattern of the climatic change due to the current incomplete understanding of various aspects of the complex processes. Nonetheless, the scientific results avaliable is sufficient to allow for decisive precautionary measures to be taken.

• Journal of Mechanical Science and Technology
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• 제18권8호
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• pp.1451-1460
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• 2004

A two-stroke Schnurle-type gasoline engine was modified to enable compression-ignition in both the port fuel injection and the in-cylinder direct injection. Using the engine, examinations of compression-ignition operation and engine performance tests were carried out. The amount of the residual gas and the in-cylinder mixture conditions were controlled by varying the valve angle rate of the exhaust valve (VAR) and the injection timing for direct injection conditions. It was found that the direct injection system is superior to the port injection system in terms of exhaust gas emissions and thermal efficiency, and that almost the same operational region of compression-ignition at medium speeds and loads was attained. Some interesting combustion characteristics, such as a shorter combustion period in higher engine speed conditions, and factors for the onset of compression-ignition were also examined.

• 패션비즈니스
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• 제14권3호
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• pp.90-96
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• 2010

We are stepping into so called "aged society" stage, as the mature people account for 7% of the population by UN's standard yardstick. The goal of this research is to provide the fundamental source in producing ecological lifestyle uniforms of health and substantiality: LOHAS which are relevant to high performance and healthy body and take things like architecture, driving, surroundings, and recycling as main factors. the results of study were as follows: Therefore we can predict, through exerting researches about consumer's usage and preference of uniforms, that the garment business will be upgraded to the medical welfare and urban life style business level. All of the silver town resident we researched wear silver town uniforms, and the uniforms were chosen by the owner and operator. This research was processed through the survey of supervisors who were employed in senior residences. 66% of elderly changed their clothes for laundary every 2 days, The timing of removal of the old uniform was that 17% was less than 1 years, consideration of buying silver-town uniforms were consider materials, design, laundary, convenience of administration, durability, color, cost.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
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• pp.421-424
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• 2004

This paper focuses on the problem of determining the quantity and timing of disassembling used products while satisfying the demand of their parts or components over a planning horizon. The case of multiple product types with parts commonality is considered for the objective of minimizing the sum of setup, disassembly operation, and inventory holding costs. A heuristic is suggested, in which an initial solution is obtained using a linear programming relaxation method, and then improved by perturbing the given solution using a dynamic programming approach and a look-ahead check while considering the trade-offs among different cost factors.

• 산업공학
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• 제25권4호
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• pp.441-449
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• 2012

Solar PV(photovoltaic) is paid great attention to as a possible renewable energy source to overcome recent global energy crisis. However to be a viable alternative energy source compared with fossil fuel, its market competitiveness should be attained. Grid parity is one of effective measure of market competitiveness of renewable energy. In this paper, we forecast the grid parity timing of solar PV energy in Korea using two factor learning curve model. Two factors considered in the present model are production capacity and technological improvement. As a result, it is forecasted that the grid parity will be achieved in 2019 in Korea.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1998년도 추계학술대회 논문집
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• pp.63-66
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• 1998

In the implementation of the simplex method program, the representation and the maintenance of basis matrix is very important, In the experimental study, we investigates Suhl's idea in the LU factorization and LU update of basis matrix. First, the triangularization of basis matrix is implemented and its efficiency is shown. Second, various technique in the dynamic Markowitz's ordering and threshold pivoting are presented. Third, modified Forrest-Tomlin LU update method exploiting sparsity is presented. Fourth, as a storage scheme of LU factors, Gustavson data structure is explained. Fifth, efficient timing of reinversion is developed. Finally, we show that modified Forrest-Tomlin method with Gustavson data structure is superior more than 30% to the Reid method with linked list data structure.

• 대한치과교정학회지
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• 제29권1호
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• pp.129-136
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• 1999

유착, 부적절한 교정치료, 과잉치, 낭종, 비정상적인 맹출경로등의 국소적인 원인으로 인하여 구치부의 매복이 발생할 수가 있다. 매복치는 적절한 치료를 하지 않으면, 교합기능의 상실, 영구치의 상실, 대합치의 정출, 인접치의 치근흡수등을 야기 할 수가 있다. 매복치를 성공적으로 맹출유도하기 위해서는 매복치의 치근형성여부가 중요한 요소가 되며, 매복치의 치근형태, 주위환경등을 유의한 적절한 교정력이 가해져야 한다.

• 농업과학연구
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• 제41권1호
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• pp.23-27
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• 2014

Potato late blight occurrence is caused by various environmental factors, and the progress can be regularly predicted so that several predictive models have been developed. The models predict the timing of the disease occurrence, but they do not include the methods of the disease control. Effective fungicide control, economic threshold, prediction models were investigated in the study to reflect on customized control modules for the model forecasting the occurrence of potato late blight.