• 상하수도학회지
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• 제29권5호
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• pp.551-557
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• 2015

The TMDL (Total Maximum Daily Load) has been used to determine the water quality target. LDC (Load Duration Curve) based on hydrology has been used to support water quality assessments and development of TMDL. Also FDC (Flow Duration Curve) analysis can be used as a general indicator of hydrologic condition. The LDC is developed by multiplying FDC with the numeric water quality target of the factor for the pollutant of concern. Therefore, this study was to create LDC using the stream flow data and numeric water quality target of BOD and T-P in order to evaluate the pollutant load characterization by flow conditions in Heukcheon stream. When it is to be a high-flows condition, BOD and T-P are necessary to manage. BOD and T-P did not satisfy the numeric water quality target for both seasons (spring and summer). In order to meet the numeric water quality target in Heukcheon stream, management of non point source pollutant is much more important than that of point source pollutant control.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1996년도 추계학술대회발표논문집; 고려대학교, 서울; 26 Oct. 1996
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• pp.166-169
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• 1996

Well-evaluated quality of software can provide business proper decisions, increase productivity, and prevent financial loss or unnecessary burden of rework. Evaluation is important to ensure the chosen software conforming to organizational requirements, customer demands, and product integrity level. In this paper, we present a theoretical model with the structure of evaluation requirements to select the prioritized evaluation target input of software quality. Within limited time and budget, the prioritized target inputs of evaluation can be used to determine the appropriate evaluating step for each different category of requirements.

• International Journal of Quality Innovation
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• 제6권2호
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• pp.31-45
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• 2005

The target costing technique, mathematically discussed by Sauers, only uses the $C_p$ index along with Taguchi loss function and ${\bar{X}}-R$ control charts to set up goal control limits. The new specification limits derived from Taguchi loss function is linked through the $C_p$ value to ${\bar{X}}-R$ control charts to obtain goal control limits. This study further considers the reflected normal loss function as well as the $C_{pk}$ index along with its lower confidence interval in forming goal control limits. With the use of lower confidence interval to replace the point estimator of the $C_{pk}$ index and reflected normal loss function proposed by Spiring to measure the loss to society, this modified and improved target costing technique would become more robust and applicable in practice. Finally, an example is provided to illustrate how this modified and improved target costing technique works.

• 품질경영학회지
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• 제41권3호
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• pp.413-421
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• 2013

Purpose: System availability and life cycle cost are often used to evaluate the system performance and is influenced by the operation and maintenance characteristic. In this paper, we propose the method to improve life cycle cost and satisfy the target availability through redundancy allocation. Methods: We consider the redundancy is available at all items in multi level system. Thus, we assume that sub-assembly, module, components can be duplicated. Simulation and genetic algorithm are employed to optimize redundancy allocation. Results: Target availability is higher, the life cycle cost is increased. In addition, the items for redundancy are selected at higher level in multi level system if target availability is higher. Conclusion: We could know that target availability affects the duplication number of items and the selection of redundancy items. For further study, we will consider new optimization algorithms to compare with the proposed GA algorithm and improve optimization performance.

• Investigative Magnetic Resonance Imaging
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• 제25권1호
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• pp.10-22
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• 2021

Purpose: To overcome the difficulty in building a large data set with a high-quality in medical imaging, a concept of 'blended-transfer learning' (BTL) using a combination of both source data and target data is proposed for the target task. Materials and Methods: Source and target tasks were defined as training of the source and target networks to reconstruct cardiac CINE images from undersampled data, respectively. In transfer learning (TL), the entire neural network (NN) or some parts of the NN after conducting a source task using an open data set was adopted in the target network as the initial network to improve the learning speed and the performance of the target task. Using BTL, an NN effectively learned the target data while preserving knowledge from the source data to the maximum extent possible. The ratio of the source data to the target data was reduced stepwise from 1 in the initial stage to 0 in the final stage. Results: NN that performed BTL showed an improved performance compared to those that performed TL or standalone learning (SL). Generalization of NN was also better achieved. The learning curve was evaluated using normalized mean square error (NMSE) of reconstructed images for both target data and source data. BTL reduced the learning time by 1.25 to 100 times and provided better image quality. Its NMSE was 3% to 8% lower than with SL. Conclusion: The NN that performed the proposed BTL showed the best performance in terms of learning speed and learning curve. It also showed the highest reconstructed-image quality with the lowest NMSE for the test data set. Thus, BTL is an effective way of learning for NNs in the medical-imaging domain where both quality and quantity of data are always limited.

• 품질경영학회지
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• 제49권3호
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• pp.421-431
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• 2021

Purpose: For improving outgoing quality, this study presents a novel sampling framework based on predictive analytics. Methods: The proposed framework is composed of three steps. The first step is the variable selection. The knowledge-based and data-driven approaches are employed to select important variables. The second step is the model learning. In this step, we consider the supervised classification methods, the anomaly detection methods, and the rule-based methods. The applying model is the third step. This step includes the all processes to be enabled on real-time prediction. Each prediction model classifies a product as a target sample or random sample. Thereafter intensive quality inspections are executed on the specified target samples. Results: The inspection data of three Samsung products (mobile, TV, refrigerator) are used to check functional defects in the product by utilizing the proposed method. The results demonstrate that using target sampling is more effective and efficient than random sampling. Conclusion: The results of this paper show that the proposed method can efficiently detect products that have the possibilities of user's defect in the lot. Additionally our study can guide practitioners on how to easily detect defective products using stratified sampling

• 제어로봇시스템학회논문지
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• 제21권2호
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• pp.162-167
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• 2015

In this paper, we propose a F-MBE algorithm for Dual mode seeker (CCD and IIR). The MBE algorithm show improved performance at the IIR target size estimation. but the MBE can't use at Dual Mode seeker. To overcome this problem,, we apply template matching method for CCD target size information. The performance of proposed F-MBE method is tested at target intercept scenario of dual mode seeker equipped missile. The experiment results show that the proposed algorithm has the relatively improved performance.

• 한국의학물리학회지:의학물리
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• 제28권4호
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• pp.181-189
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• 2017

The conventional delivery quality assurance (DQA) process for RapidArc (Varian Medical Systems, Palo Alto, USA), has the limitation that it measures and analyzes the dose in a phantom material and cannot analyze the dosimetric changes under the motional organ condition. In this study, a DQA method was designed to overcome the limitations of the conventional DQA process for internal target volume (ITV) based RapidArc. The dynamic DQA measurement device was designed with a moving phantom that can simulate variable target motions. The dose distribution in the real volume of the target and organ-at-risk (OAR)s were reconstructed using 3DVH with the ArcCHECK (SunNuclear, Melbourne, USA) measurement data under the dynamic condition. A total of 10 ITV-based RapidArc plans for liver-cancer patients were analyzed with the designed dynamic DQA process. The average pass rate of gamma evaluation was $81.55{\pm}9.48%$ when the DQA dose was measured in the respiratory moving condition of the patient. Appropriate method was applied to correct the effect of moving phantom structures in the dose calculation, and DVH data of the real volume of target and OARs were created with the recalculated dose by the 3DVH program. We confirmed the valid dose coverage of a real target volume in the ITV-based RapidArc. The variable difference of the DVH of the OARs showed that dose variation can occur differently according to the location, shape, size and motion range of the target. The DQA process devised in this study can effectively evaluate the DVH of the real volume of the target and OARs in a respiratory moving condition in addition to the simple verification of the accuracy of the treatment machine. This can be helpful to predict the prognosis of treatment by the accurate dose analysis in the real target and OARs.

• 한국물환경학회지
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• 제29권4호
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• pp.531-539
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• 2013

In order to apply a water quality indicator as a certain target pollutant, the indicator should have the representability of an index for the management of Total Maximum Daily Loads (TMDLs). Scientific groundwork and treatment technologies also should be provided for the application of the indicator. This study analyzed the applicability of major water quality indicators for target pollutants. The results showed that four water quality indicators of TOC, T-N, SS & T-Coli can be considered as target pollutants besides existing BOD and T-P. These indicators can be applied with the preparations such as essential basic data, pollution load estimation framework as well as legal criteria setting when the need is raised. As the importance of TOC, which is considered as a replacement of BOD, is emphasized, technical and institutional terms are being prepared in order to determine TOC as another target pollutant in the near future. It could be considered to combine TOC with BOD for the time being during the $3^{rd}$ stage of TMDLs in view of the present conditions for the management of TOC. TOC can be the most effective index for the organic matter and help to be managed more systematically in the waterbodies where rivers and lakes are mutually connected.

• 환경영향평가
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• 제28권6호
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• pp.536-548
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• 2019

기타 수계 중 삽교천 유역에 새롭게 수립된 오염총량관리제도의 시행에 따른 효과를 정량화하기 위해 2015년을 기준으로 유역유출모형인 HSPF 모형을 구축한 후, 최종 목표연도인 2030년의 부하량을 입력하여 각 단위유역 말단에 설정된 목표수질 달성여부를 평가하였으며, 미시행지역인 무한천과 삽교천 유역을 포함하여 유량구간별 수질(BOD, T-P)을 예측하였다. 보정 및 검증이 완료된 모형에 2030년의 부하량을 입력하여 재구동한 후, 모의결과로부터 부하지속곡선을 작성함으로써 기준년도 부하량을 입력하여 구동한 모의 수질과 목표연도 부하량을 입력하여 모의한 예측 수질을 유량구간별로 도식화한 결과, 평수량 구간(40~60%)에서 3개의 단위유역 모두 BOD 목표수질에 근접하게 모의되었으며, 목표수질 달성율도 높게 산정되었다. T-P의 경우, 천안A 46%, 곡교A 29%, 남원A 25% 정도의 수질이 개선되는 것으로 예측되었으며, 무한천과 삽교천유역은 중권역 목표기준인 III등급 이내의 수질로 모의되었다. 총량관리 대상 단위유역은 목표수질을 달성하고, 미시행지역은 목표등급을 달성하는 수준의 수질이 삽교호 내로 유입될 것으로 예측됨으로써 총량제 시행에 따른 삽교천 유역의 수질개선효과가 긍정적일 것으로 판단된다.