• Journal of Korean Society of Environmental Engineers
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• v.27 no.4
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• pp.362-368
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• 2005

The pH, alkalinity and calcium hardness could be adjusted by $CO_2$, $Ca(OH)_2$, and $Na_2CO_3$ addition in the water treatment process for corrosion protection of the water pipes. This research was performed to investigate the effect on the variation of water quality on the unit process by addition $CO_2$, $Ca(OH)_2$, and $Na_2CO_3$ in water treatment process. Carbon dioxide and lime were added before the coagulation basin and soda ash was added after the BAC process. pH and aklainity were increased at coagulation basin then after the water qualities had sustained similiarly to BAC process. There was no effect on turbidity and DOC removal efficiency during experimental period by addition\ $CO_2$, $Ca(OH)_2$, and $Na_2CO_3$ solution was added into clear well, the last process for optimum control of CCPP and is used mainly to control pH and alkalinity. In this research, average pH, alkalinity, and calcium hardness in treated water were 8.39, 61.4 mg/L as $CaCO_3$, 59.4 mg/L as $CaCO_3$, respectively and CCPP of treated water was higher than 29.5 mg/L to BAC process water, so adjusted water was expected to prevent internal corrosion of water pipe.

• Proceedings of the Korean DIstribution Association Conference
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• 2006.02a
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• pp.43-78
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• 2006

While trust and commitment, essential ingredients of the relationship quality variables, are core mediating variables for the purpose of maintaining the long-term relationship, in the context of the internal political economy of company and the relational performance of its members, there have been limited studies which explore as to how each of the dimensions have affect differently. The basic purpose of this study is to examine the relationship between an automobile manufacturer and its agencies. The main purpose of this study is to examine how each different dimension of trust and commitment on the automobile manufacturer have different mediating effects in the context of internal political economy variables and relational performance perceived by its agents. Another purpose is to investigate the mechanism by which the relational performance of the agencies is improved. An empirical study surveying 115 sales office managers at a leading automobile manufacturer in Korea was conducted. An analysis of the collected data indicates that while internal political economy variables have a positive influence on the agencies' relational performance through the mediating role of trust and commitment, agencies' benevolence on its headquarter has a different influence on the dimensions of commitment. Currently, an automobile manufacturer is advised to implement the relational management philosophy in dealing with its agencies with an hope of innovative orientation for customers. In this sense, this study is a big stride in providing ample implications for the automobile manufacturer in establishing trust and commitment, which are the prerequisite conditions in developing and maintaining a successful long-term relationship with its agencies, and in improving the agency's relational performance.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.204-211
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• 2020

This study investigates the 17 ordinances on the improvement of labor condition and status of social workers in the metropolitan city of Busan that has 16 administrative borough, or gu, and a central headquarter, and further verifies its implementation. Researchers identified the presence of 9 articles in each ordinances, followed by data request being made to all the administrative offices for their implementation. As a result, the articles on obligation, research on the actual condition, support plan and committee establishment have been excluded in many gus, which were in default of implementation or slower than ordinances stipulate. It is suggested that statements about the obligation of the head officers, preceding research on the actual condition before support plan and committee establishment should be made in the independent articles. Regarding its implementation, ordinances are required to have a regulatory power through penalty, reflect the actual demands of social workers in the field and go through a regular evaluation and monitoring on its implementation in order for purpose accomplishment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.23-30
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• 2017

In the AEC(Architecture, Engineering and Construction) industry, BIM(Building Information Modeling) technology not only helps design intent efficiently, but also realizes an object-oriented design including building's life cycle information. Thus it can manage all data created in each building stage and the roles of BIM are greatly expanded. Contractors and designers have been trying to adopt BIM to design competitions and validate it for the best result in various aspects. Via the computational simulation which differs from the existing process, effective evaluation can be done. For this process, a modeling guideline for each kind of BIM tool and a validation system for the confidential assessment are required. This paper explains a new process about design evaluation methods and process using BIM technologies which follow the new paradigm in construction industry through complement points by an example of a competition activity of the Korea Power Exchange(KPX) headquarter office. In conclusion, this paper provides a basic data input guideline based on open BIM for automatic assessment and interoperability between different BIM systems and suggests a practical usage of the rule-based Model Checker.

• International Commerce and Information Review
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• v.18 no.2
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• pp.195-218
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• 2016

This study seeks to find out the determinants of subsidiary performance. In addition, moderating effect of autonomy on the relationship between subsidiary competence, subsidiary relationship and subsidiary configurational focus, and subsidiary performance. In studying the moderating effect of autonomy on subsidiary performance, the results will give invaluable insights to foreign subsidiaries in Korea to better compete in competitive Korean market. The results of empirical study showed that subsidiary with higher level of interaction with its intra-MNC network has higher level of performance. Thus, active interaction with headquarter and its affiliates will lead to better performance. Subsidiary with higher level of competence has higher level of performance. Thus, subsidiary should attain higher level of competence to better compete in Korea. Subsidiary autonomy has moderating effect on the relationship between configurational focus and performance. Thus, optimal MNC subsidiary configuration and attainment of subsidiary autonomy is needed to secure competitiveness in Korean market.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.547-554
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• 2006

The overall objective of this research was to find out the role of rapid mixing conditions in the species of hydrolyzed Al(III) formed by Al(III) coagulants and to evaluate the distribution of hydrolyzed Al(III) species by coagulant dose and coagulation pH. When an Al(III) salt was added to water, monomeric Al(III), polymeric Al(III), precipitate Al(III) was formed by Al(III) hydrolysis. The method of hydrolyzed Al(III) species characterization analysis was based on timed spectrophotometer with ferron as a color developing reagent. The hydrolytic species were divided into monomer, polymer, precipitate from the reaction kinetics. And then, the color intensity for monomeric Al(III) was read 3 min after mixing. With standard Al solution containing monomeric Al(III) only, the Al-ferron color intensity slightly increased with until about 3 min. During the rapid mixing period, for purewater, formation of dissolved Al(III) (monomer and polymer) was similar to rapid mixing condition, but for raw water, the species of Al(III) hydrolysis showed different result. During the rapid mixing period, for high coagulant dose, Al-ferron reaction increases rapidly. The kinetic constants, Ka and Kb, derived from Al-ferron reaction. The kinetic constants followed very well the defined tendencies for coagulation condition. For pure water, when the rapid mixing time increased, the kinetic constants, Ka and Kb showed lower values. Also, for raw water, when the rapid mixing time increased, the kinetic constants, Ka and Kb showed lower values.

• Journal of the Korean earth science society
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• v.22 no.3
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• pp.186-194
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• 2001

The operational meso-scale short range NWP system was developed for Cheju Regional Meteorological Office located at Cheju island, Korea. The Central Meteorological Service Center, KMA has reported the information on numerical weather prediction every 12 hours. But this information is not enough to determine the detail forecast for the regional meteorological office because the terrain of the Korean peninsula is very complex and the resolution of the numerical model provided by KMA headquarter is too coarse to resolve the local severe weather system such as heavy rainfall. LAPS and MM5 models were chosen for three-dimentional data assimilation and numerical weather prediction tools respectively. LAPS was designed to provide the initial data to all regional numerical prediction models including MM5. Synoptic observational data from GTS, satellite brightness temperature data from GMS-5 and the composite reflectivity data from 5 radar sites were used in the LAPS data assimilation for producing the initial data. MM5 was performed on PC-cluster based on 16 pentium CPUs which was one of the cheapest distributed parallel computer in these days. We named this system as Halla Short Range Prediction System (HSRPS). HSRPS was verified by heavy rainfall case in July 9, 1999, it showed that HSRPS well resolved local severe weather which was not simulated by 30 km MM5/KMA. Especially, the structure of rainfall amount was very close to the corresponding observation. HSRPS will be operating every 6 hours in the Cheju Regional Meteorological Office from April 2000.

• Journal of the Korean Geographical Society
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• v.40 no.6 s.111
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• pp.631-652
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• 2005

This study is to clarify regional structure and connection of international physical distribution through clearance depot of Cheongju customs of inland location. The trade of clearance depot of Cheongju customs industrial characteristics reflects of territorial hinterland. As origins and destinations of freight as exports and imports region, territories of Cheongju customs trade mainly with Japan, China, and USA. Origin and destination of freight of Cheongju customs territory are hinterland and foreland of Incheon International Airport and Busan port. In case of export, foreland of Busan port is board, and in case of import, the hinterlands of Incheon International Airport and Busan port are similar. Clearance depot of inland-located Cheongju is construct by the advantages of rapidness and inexpensive cost. And the kind of freight and system of physical distribution of each enterprise show different characteristics. For each export and import freight, each shipper corporation has its own physical distribution system, and structure of international distribution is classified into export pattern of bonded industry and bonded warehouse. Again the patterns of bonded warehouse are distinguished free on board price system with division of labor in base of production in overseas, free on board price system, and cost-insurance-freight with division of labor in base of production in overseas. These Phenomena are caused by transaction between headquarter and its overseas corporation, initiative freight handling of export corporation, choice of inexpensive cost, and international convention.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.4
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• pp.589-609
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• 2017

This study carried out the density and energy dispersive X-ray spectroscopy and particle size analysis which are the physical characteristics of coal dust by collecting samples of coal dust in the five domestic mines to control the coal dust through ventilation in the workplace for coal mining in the country. This will contribute to a more comfortable working environment by understanding the physical characteristics of the coal dust which is derived from any hard coal produced domestically. In particular, the result of PSA analysis showed that the size of coal dust sample for this study ranged from $0.007{\sim}88.614{\mu}m$ were the particles less than $3.5{\mu}m$, the size range responsible for pneumoconiosis. To observe the flow of coal dust collected on the wind speed, the fallout of coal dust produced by the wind tunnel for the wind was measured and the particle size analysis of coal dust fallout was carried out. In addition, airborne dust is measured according to the mine velocity by using a multi-stage Anderson sampler in the mine where fine dust is generated in a large amount and the wind speed is found out to control the coal dust below $3.5{\mu}m$. In addition, natural ventilation pressure of A mine was calculated to prevent over design of the main fan.

• Korean Chemical Engineering Research
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• v.45 no.5
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• pp.500-505
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• 2007

The objectives of this research were to (1) identify the membrane fouling potential due to different fractions of NOM (2) correlate the physicochemical properties of NOM and membranes with the adsorption of humic substances on membrane (4) find out the effect of membrane physical and chemical washing according to membrane material. The static adsorption test and adsorption test showed that hydrophobic organics adsorbed much more quickly than hydrophilic organics. In case of the effect of membrane properties on the adsorption of organic fractions, the adsorption rate ratio(a) of hydrophobic membrane (0.016, 0.077) was greater than that of hydrophilic membrane (0.010, 0.033) regardless of the kind of organic fractions. This suggests that the UF membrane fouling were occurred mainly by internal pore size decreasing due to adsorption of organic into pore surface for hydrophobic membrane, and by sieving of organics and forming a gel layer on the membrane surface for hydrophilic membrane. In conclusion, the decrease in the pore volume, which was caused by the organic adsorption into the internal pore, was greater with the hydrophobic membrane than with the hydrophilic membrane. In case of the effect of membrane properties on permeate flux, the rate of flux decline for the hydrophobic membrane was significantly greater than that for the hydrophilic membrane.