• Journal of Korean Society for Quality Management
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• v.29 no.4
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• pp.1-17
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• 2001

The characteristics of Telecommunication Industry encompass not only hardware and software but also the service aspect of them. One way to improve the industry up to the international level in terms of hardware and software as well as service aspect is to comply with tile TL 9000 standard, which was established by QUEST Forum, the group consisted of U.S. communication industry, based on the ISO 9000 Quality Management System. In this study, design, establishment, implementation, maintenance and improvement of quality system for domestic telecommunication industry are thoroughly investigated based on TL 9000 standard, with its LCM(Life Cycle Model) model and measurements. Also, Process Approach is suggested to help the industry realize the system to meet its specific needs. In addition, specific examples with the successful certification to TL 9000 standard are presented.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.198-202
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• 2006

국내의 대표적인 지하수 오염물질인 trichloroethylene(TCE)을 반응벽체의 일종인 영가철을 이용하여 처리할 때 계면활성제가 미치는 영향을 다양한 계면활성제를 이용하여 조사하였다. 비이온성 계면활성제와 음이온성 계면활성제는 TCE의 탈염소화 반응속도는 감소시켰으나 양이온성 계면활성제는 임계미셀농도 (CMC) 미만에서는 반응속도를 증가시켰으나, CMC 이상의 농도에서는 반응속도를 감소시켰다. 양이온성 계면활성제는 TCE의 철 표면 흡착을 증가시켜, 철 표면에서 일어나는 TCE의 탈염소화 반응속도를 증가시키는 것으로 사료된다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.355-359
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• 2006

토양에 누적된 오염물질은 지하수 유동과 연계하여 점차 주변지역으로 확산된다. 본 조사는 오염의 개연성이 높은 산업단지를 선정하고 그 중에서도 유해화학물질의 사용이 많은 지역을 대상으로 토양과 지하수의 오염도조사를 수행하였다. 토양오염도 조사는 160개 지점에서 토양시료를 채취하여 오염물질을 분석하였으며 분석결과 TPH물질은 최고 23,151mg/kg, BTEX는 최고 1,657mg/kg로 검출되었다. 오염특성은 유류(TPH, BTEX) 물질 이외에도 TCE, PCE◎물질과같은 염소계 유기용제에 의한 오염도 확인할 수 있었으나 중금속 물질에 의한 오염은 우수 방류구와 같은 일부 지역에서 검출되었다. 지하수 수질의 경우 페놀, 비소, 납, BTEX, TCE, PCE 물질들이 복합적으로 오염되어있는 것으로 나타났다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.155-158
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• 2005

본 연구에서는 현장규모의 biopile을 제작하여 유류로 오염된 토양을 정화하였다. 오염토양의 TPH농도는 평균 2,800mg/kg(최고 3,590mg/kg)이었으며, 오염토양의 양은 $746m^3$이었다. Biopile $(17{\times}20{\times}2.5m)$을 약 3개월간 운전하며 일정 시간 간격으로 토양가스($O_2,\;CO_2)$ 및 VOCs) 및 토양의 TPH농도를 분석하였다. 지속적인 공기의 주입/추출에 의해 biopile내부는 호기조건을 유지하였으며, 미생물의 활성도 증가에 따라 이산화탄소의 농도가 증가하는 경향을 나타내었다. 또한 토양가스 분석결과 휘발성 유기오염물질(VOCs)은 약 40일 경과 후 90% 제거되었으며, 90일 경과 후 토양의 TPH 제거율은 98%로 나타났다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.219-222
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• 2005

유류로 오염된 토양에 대해 토양경작법(Landfarming)을 적용하여 복원효율을 평가하였다. 복원 초기에는 주로 휘발에 의한 오염물질의 저감이 이루어졌으며, 이 후 미생물성장에 필요한 토양뒤집기와 질소원 영양물질의 공급으로 인해 미생물수가 복원초기에 비해 약 200배 증가하면서 약 30여일 경과 후 초기 20,000ppm에서 복원목표인 TPH의 토양오염우려기준 2,000ppm의 이하인 1,910ppm으로 감소하였다. 시간이 경과할수록 탄소원 섭취기질 부족으로 완만한 오염물질 감소속도를 나타내면서 최종적으로 TPH를 측정한 결과 1,288ppm으로서 제거효율 94%이상을 나타내었다.

• Journal of Information Technology Services
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• v.18 no.5
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• pp.99-117
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• 2019

In recent years, the one-person media has increasingly gained popularity. The purpose of this study is to investigate the relationship among the service quality, satisfaction and intention of continuous use of one-person media service and to further examine the mediating effect of satisfaction operating on the relationship between the service quality and intention of continuous use. Based on the literature review, hypotheses were developed and the research model was built for testing. The sample of 358 users was selected to achieve these objectives. From the analysis of PLS(Partial Lease Square Path Analysis), key research findings are summarized as follows. First, relationships among the service quality, satisfaction, and intention of continuous use were all positively correlated each other. Second, the effect of service quality on intention of continuous use was mediated by satisfaction. Third, the content quality of one-person media has the higher effectiveness than platform quality to satisfaction and intention of continuous use. Results of this paper are expected not only to emphasize the importance of satisfaction based on the service quality, but also to provide multifaceted implications and directions for the management of one-person media service effectively.

• Journal of Soil and Groundwater Environment
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• v.17 no.3
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• pp.32-38
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• 2012

This study was conducted to evaluate the slurping process affecting the variation of free product and VOCs concentration and the bioaugmentation effect on bioremediation process. Free products and soil gas were extracted from 30 extraction wells installed in a petroleum contaminated area. The extraction system was operated for 10 hours per day with 1 hour on-and-off mode. The thickness of free product in extraction well was decreased from 11.7 cm to 4.5 cm and the VOCs concentration was increased from 10.37 ppm to 30.78 ppm during the operation period. After the slurping process for 2 months, contaminated soil was treated with bioremediation process in 2 cells, $15{\times}40$ m, biologically enhanced with adjusting oxygen, moisture and nutrients concentration. Total 1,400 L of microbial inoculant, Naturesys. (Dong Myung Ent. Co.) was added to the pile B, which has an outstanding ability for degrading petroleum hydrocarbons. The results showed that bioremediaton effect in soil with the microorganisms solution is 33% higher than that in soil with only residual bacteria.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.10
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• pp.1573-1580
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• 2013

This study is proposed traffic signal operating system to find existing problems of loop system and complex with doplar system, which have strong linearity, resistence of weather effects and wide range to improve delay problems that used in vehicle detection method. This proposed method have simulated on Southern-Gwangju station to Enter of SeoChang take about 10km by using VISSIM tool and we found this proposed method is 15% through(또는 to) 30% more effective than continuous progress interlocking system or crossing progress interlocking system.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.17-23
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• 1976

In order to investigate the fate of nitrogen in the paddy soil, Suchang, Hwasoon and Susan soil which have different properties, were treated with several nitrogen fertilizers such as ammonium chloride, ammonium sulfate, urea and SCU (sulfur-coated urea), and incubated under water-logged condition in $30^{\circ}C$ incubator. $NH_4-N$, $NO_3-N$, $Fe^{++}$ and pH in soil and stagnant water, were determined at 10, 20, 30, 40 and 50 days after incubation. The obtained results were summarized as follows: 1. The effect of rising temperature was increased in order of Hwasoon>Suchang>Susan and the effect of air drying soil was risen in order of Susan>Hwasoon>Suchang, while the rate of ammonication was in order of Susan>Suchang>Hwasoon. 2. The changes of $NH_4-N$ in stagnant water was dependent upon the nitrogen concentration of $NH_4Cl$ and $(NH_4)SO_4$ plat was high and decreased after 30 days incubation, but increased after 40 days and then decreased again. In contrast with the above, $NH_4-N$ concentration of urea and SCU plot was low but the change showed slightly through the incubation period. 3. Accumulation of $NH_4-N$ in the oxidative layer of the $NH_4Cl$ and $(NH_4)_2SO_4$ plot was higher than that of urea and SCU plot and $NH_4-N$ content was decreased with the incubation period. The change of $NH_4-N$ in the reductive layer showed the same pattern. 4. The changes of $NO_3-N$ in the stagnant water were different according to soil properties and nitrogen fertilizer. $NO_3-N$ concentration in stagnant water of urea and SCU plot was higher than in the $NH_4-Cl$ $(NH_4)_2SO_4$ plot and nearly disappeared after 30 to 40 days incubation. 5. The $NO_3-N$ concentration in the oxidative layer of soil was higher than reductive layer. The pattern of change was different in accordance with soil properties and nitrogen fertilizers. In general, nitrification in urea and SCU plot was more increased than $(NH_4)_2SO_4$ plot. In reductive layer, the concentration of $NO_3-N$ was very low until 30 days incubation and thereafter increased slightly. 6. Upon the concentration of $NH_4-N$ and $NO_3-N$ in stagnant water and soil, it was assumed that denitification of urea and SCU plot was higher than $NH_4Cl$ and $(NH_4)_2SO_4$ plot and denitrified nitrogen in incubation period was above 50%.

• Journal of Soil and Groundwater Environment
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• v.12 no.3
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• pp.17-22
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• 2007

The feasibility of soil washing was investigated to remediate Pb-contaminated field soil. Hydrochloric acid was used as a washing agent. As mixing time increased from 5 min to 120 min, removal efficiency of Pb from contaminated soil increased from 69.3% to 81.9%. Two times washing with 0.2 M HCl showed 96% removal efficiency even at mixing time of 10 min. The Pb content in soil increased sharply as particle size of soil decreased, and removal efficiency was highly dependent on mixing time and temperature. Based on this result, acid washing technologies can be applied to remediate the Pb-contaminated soil used in this study.