• Journal of Industrial Technology
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• v.21 no.B
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• pp.233-240
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• 2001

This research was conducted with the aim of efficiently managing large scale of rivers such like Songyang-river through predicting water quality change with analyzing the characteristics of the flowing in nutrients and pollutants. The main result will be used as basic data for effectively operating reservoirs through controling water quality and quantity. The relationship between quantity of flow and water quality was analyzed and pollution loading into the basin was estimated. Three areas of Soyang-river upstream and one area of Suip-cheon in Yanggu-gun were selected as research sites. Flow and water quality were measured simultaneously. The relation between quantity of discharge and pollution concentration and between quantity of discharge and pollution loading were analyzed by statistical method, respectively. We provided a rating curve through measuring quantity of discharge(collecting quantity of discharge) and pollutograph and pollution loading curve through water quality data. Also, we analyzed the correlation between quantity of discharge per unit area and pollution loading per unit area in each basin. As resurt of this research, Buk-cheon spot revealed an excellent first grade water quality for the items including $BOD_5$, DO, and SS. The correlation coefficient between Buk-cheon spot's quantity of discharge and pollution loading was 0.896~0.996, showing the validity of analysis applying correlation curve formula of quantity of discharge and pollution loading in the same spot. Also, pollution loading per unit area of the items including $BOD_5$, COD, DO, SS, T-N, T-P increased as the area of basins get increased following the sequence of Buk-cheon, Suip-cheon, Naelin-cheon spots.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.327-328
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• 2021

In the manufacturing process of ready-mixed concrete, quantity management directly affects the workability and strength of concrete. Therefore, water quantity is the most important management factor for water quality control of ready-mixed concrete. It can be said that the number of unit water in the mix design, the water quantity due to the surface water contained in the aggregate used, and the water quantity taking into account the concentration of sludge contained in the recycling water when using the recycling water are factors that affect the quantity management of ready-mixed concrete. In this study, as a stable quality control method of ready-mixed concrete, a quantity management method by aggregate surface water and a sludge concentration management method according to the use of recycling water were proposed. Thus, we tried to suggest an efficient quantity management method for stabilizing the quality of ready-mixed concrete.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.13 no.21
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• pp.73-79
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• 1990

The quality and cost of manufacturing products is a significant problem in view of duality assurance, but the quality level of the incoming materials is not considered to determine in the economic order quantity of conservative inventory model. A typical situation we face is the difference of quantity between order quantity and the determined outgoing quantity after acceptance inspection. In this paper we present a procedure to reduce the difference of order(ingoing) quantity and outgoing quantity of incoming materials a method of justifying the acceptance plans whether accept or not by comparing with ingoing outgoing quality.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.1
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• pp.123-130
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• 1992

The quantity point has been considered prior to the quality point in the water resources development and management. However, the quality problems have become as important as quantity problems due to the industrialization and civilization. This paper presents a methodology of the integrated management of multiple reservoir systems by considering both water quantity and quality problems. It also presents a long-term forecasting technique of reservoir water quality by using the developed phosphorous model. The methodology was applied to the Han river reservoirs operation, in which five major reservoirs were considered. The result shows that the spatially and temporally distributed water quantity and quality resources can be utilized by meeting all the required constraints.

• Journal of Korean Society for Quality Management
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• v.18 no.1
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• pp.1-8
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• 1990

In this paper we present a procedure to determine the quantity of incoming materials when the nonconforming materials appear in the production process. We determined the total loss of materials $D_2$ due to fraction defectives in process and added this $D_2$ to the quantity of incoming materials $Q_0$ considered ingoing-outgoing quality level. The quantity of materials $Q_1$ as a result of this procedure should be an economic purchasing quantity and is a rectifying quantity of the EOQ determined in classical inventory model.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.10a
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• pp.539-553
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• 2004

This paper models and solves contracting schemes for both when quality is perfectly observable and when quality is not perfectly observable in supply chain. When quality is perfectly observable, the first-best optimal solution which is that the marginal utility of procurer obtained from the quantity and quality supplied by suppliers (the price) is equal to the marginal cost to produce the quantity and quality is obtained. However, when quality is not perfectly observable to procurers the optimal solution cannot be the first-best but the second-best where the price is greater than the marginal cost to produce the quantity and quality and social welfare is less than that of the first-best solution.

• Environmental Engineering Research
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• v.14 no.2
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• pp.71-78
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• 2009

A review of stormwater quantity and quality in the urban environment is presented. The review is presented in three parts. The first part reviews the mathematical methods for stormwater quantity and has been undertaken by examining a number of stormwater models that are in current use. The important feature of models, their applications, and management has been discussed. Different types of stormwater management models are presented in the literatures. Generally, all the models are simplified as conceptual or empirical depending on whether the model is based on physical laws or not. In both cases if any of the variables in the model are regarded as random variables having a probability distribution, then the model is stochastic model. Otherwise the model is deterministic (based on process descriptions). The analytical techniques are presented in this paper.

• Journal of Korean Society on Water Environment
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• v.27 no.6
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• pp.932-937
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• 2011

Main objectives of this paper were; firstly, to explain impacts of suspended solid in the water body on the relationship between water quantity and water quality; secondly, study on the inter-relationship between organic materials, nutrients, pathogens, and suspended solids considering eco-friendly water resources. Relationship between water quality and water quantity is not easy to understand as it includes physicochemical-biological reactions and diffuse pollutions. Especially, suspended solid makes water resource management difficult. Eroded soil in the upper land transported to the downstream by water flows carrying biological and physicochemical information and sedimented in the downstream. As sediment scoured under high flow condition and environmental change, suspended solid and sediment should be emphasized for understanding the inter-relationship between water quality and water quantity. Knowledge gaps between known monitored data and management of suspended solid were identified as well for future study.

• Korean Journal of Veterinary Service
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• v.41 no.2
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• pp.63-69
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• 2018

This study was conducted to evaluate the effect of tuberculin test and associated various environmental factors on the quantity and quality of milk production of daily cows. The change of milk quantity followed to tuberculin test was investigated on 109 daily farms in south Gyeonggi, and the change of milk quality was also studied on 48 daily farms. The result of this study showed that the quantity and quality of milk production was decreased after tuberculin test (P<0.05). The amount of loss of the milk production due to tuberculin test was, however, only 0.92 L per cow. In terms of milk quality, the level of total protein was statistically significantly decreased. This study also showed that the milk quality was further decreased when the cows were restraint after veterinarians arrived compared to the case that cows were stayed restraint before the veterinarians visited the farm. In addition, milk quality and quantity were lowered worse when relative humidity of the location of tuberculin test was lower than 50% or higher than 70%, or when the milk production of a farm is higher than its quarter. This study showed that stress on daily cows and the farmers induces the decrease of milk yield and milk quality, and these losses can be minimized by regulating various environmental factors to the direction to maximize productivity.

• Environmental Engineering Research
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• v.14 no.3
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• pp.143-149
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• 2009

In this paper, review of stormwater quality and quantity in the urban environment is presented. The review is presented in three parts. This second part reviews the mathematical techiques used in the stromwater quality modelling and has been undertaken by examining a number of models that are in current use. The important features of models are discussed.