• Journal of the Korean Institute of Gas
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• v.23 no.4
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• pp.1-9
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• 2019

Large-scale industrial boilers operating at high temperature and high pressure, have a large amount of water, and a large amount of energy is released at the time of explosion. Currently, most industrial boilers use gas fuel such as LNG and LPG, etc. and fuel exists in the same space as equipment, so there is a high possibility of secondary damage such as fire or explosion in the event of a boiler accident. Both special care and management are required to operate the very dangerous equipment that causes casualty 2.51 per accident. For boilers of a certain size or more, the Korea Energy Agency conducts inspections in accordance with the Energy Usage Rationalization Act, KS, and public notice of the Ministry of Industry, Trade and Resources. In this research, based on the results of the inspection, the hazard factorss are configured, and a questionnaire is conducted to the inspector, the equipment manager, the maintenance person, and the person in charge of the manufacturer. We analyzed the results by using AHP (Analytic Hierarchy Process). As a result of analysis, generally recognized hazard factorss are not good management, measurement failure, specification failure, water leak, leak analysis, but connection, welding, scale, and corrosion, etc. are relatively less important. It is judged that the adverse factors that are recognized to be highly important among all groups and careers are already well managed, but less important and adverse factors should be well managed to ensure that the safe usage of the boiler.

• Journal of the Korean GEO-environmental Society
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• v.12 no.1
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• pp.13-26
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• 2011

Because the allowable current loading of buried electrical transmission cables is frequently limited by the maximum permissible temperature of the cable or of the surrounding ground, there is a need for cable backfill materials to be maintained at a low thermal resistivity during the service period. Temperatures greater than $50^{\circ}C$ to $60^{\circ}C$ may lead to breakdown of cable insulation and thermal runaway if the surrounding backfill material is unable to dissipate the heat as rapidly as it is generated. This paper describes the results of studies aimed at the development of backfill material to reduce the thermal resistivity. A large number of different additive materials were tested to determine their applicability as a substitute material. The results of Dong-rim river sand (relatively uniform) show that as water content level increases, thermal resistivity tends to decrease, whereas the thermal resistivity on dry condition is very high value($260^{\circ}C-cm/watt$). In addition, other materials(such as Jinsan granite screenings, A-2(sand and gravel mixture), E-1(rubble and granite screenings mixture) and SGFC(sand, gravel, fly-ash and cement mixture)) are well-graded materials with low thermal resistivity($100^{\circ}C-cm/watt$ when dry). Based on this research, 4 types of improved materials were suggested as the environmentally friendly backfill materials with low thermal resistivity.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.5
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• pp.367-377
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• 2016

The purpose of the projects for strengthening the Service Business Competitiveness, which had been sponsored by the Ministry of Trade, Industry and Energy, and managed by the NIPA, is to support for combining the whole business process of the SMEs with the business model considering the scientific aspects of the services, to enhance the productivity of them and to add the values of their activities. 5 organizations are selected in 2014, and 4 in 2015 as leading organizations for these projects. This study analyzed the efficiency of these projects using DEA. Throughout the analysis of the prior researches, this study used the amount of government-sponsored money as the input variable, and the number of new customer business, the sales revenue, and the number of new employment as the output variables. And the result of this analysis showed that the decision making unit 12, 15, and 21 was efficient. And from this study, we found out two more performance indicators such as, the number of new employment and the amount of sales revenue, besides the number of new customer businesses.

• The Korean Society of Law and Medicine
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• v.20 no.3
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• pp.175-209
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• 2019

The bundled discounting which the dominant undertakings engage in is problematic in terms of competition restraint. Bundled discounts generally benefit not only buyers but also sellers. Specifically, bundled discounts usually costs a firm less to sell multiple products. In addition, Bundled discounts always provide some immediate consumer benefit in the form of lower prices. Therefore, competition authorities and courts should not be too quick to condemn bundled discounts and apply the neutral and objective standard in bundled discounting cases. Cascade Health v. Peacehealth decision starts ruling from this prerequisite. This decision pointed out that the dominant undertaking can exclude rivals through bundled discounting without pricing its products below its cost when rivals do not sell as great a number of product lines. So bundled discounting may have the anticompetitive impact by excluding less diversified but more efficient producers. This decision did not adopt Lepage case's standard which does not require the court to consider whether the competitor was at least as efficient of a producer as the bundled discounter. Instead of that, based on cost based approach, this decision said that the exclusionary element can not be satisfied unless the discounts result in prices that are below an appropriate measures of the defendant's costs. By adopting a discount attribution standard, this decision said that the full amount of the discounts should be allocated to the competitive products. As the seller can easily ascertain its own prices and costs of production and calculate whether its discounting practices exclude competitors, not the competitor's costs but the dominant undertaking's costs should be considered in applying discount attribution standard. This case deals with bundled discounting practice of multiple healthcare services by the dominant undertaking in healthcare market. Under the Korean healthcare system and public health insurance system, the price competition primarily exists in non-medical care benefits because public healthcare insurance in Korea is in combination with the compulsory medical care institution system. The cases that Monopoly Regulation and Fair Trade Law deals with, such as cartel and the abuse of monopoly power, also mainly exist in non-medical care benefits. The dominant undertaking's exclusionary bundled discounting in Korean healthcare markets may be practiced in the contracts between the dominant undertaking and private insurance companies with regards to non-medical care benefits.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.321-327
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• 2006

In Korea, there is a growing competitive for water resources between industrial, domestic and agricultural consumer, and the environment as many other OECD countries. The demand on water use is also affecting aquatic ecosystems particularly where withdrawals are in excess of minimum environmental needs for rivers, lakes and wetland habits. OECD developed three indicators related to water use by the agriculture in above contexts : the first is a water use intensity indicator, which is expressed as the quantity or share of agricultural water use in total national water utilization; the second is a water stress indicator, which is expressed as the proportion of rivers (in length) subject to diversion or regulation for irrigation without reserving a minimum of limiting reference flow; and the third is a water use efficiency indicator designated as the technical and the economic efficiency. These indicators have different meanings in the aspect of water resource conservation and sustainable water use. So, it will be more significant that the indicators should reflect the intrinsic meanings of them. The problem is that the aspect of an overall water flow in the agro-ecosystem and recycling of water use not considered in the assessment of agricultural water use needed for calculation of these water use indicators. Namely, regional or meteorological characteristics and site-specific farming practices were not considered in the calculation of these indicators. In this paper, we tried to calculate water use indicators suggested in OECD and to modify some other indicators considering our situation because water use pattern and water cycling in Korea where paddy rice farming is dominant in the monsoon region are quite different from those of semi-arid regions. In the calculation of water use intensity, we excluded the amount of water restored through the ground from the total agricultural water use because a large amount of water supplied to the farm was discharged into the stream or the ground water. The resultant water use intensity was 22.9% in 2001. As for water stress indicator, Korea has not defined nor monitored reference levels of minimum flow rate for rivers subject to diversion of water for irrigation. So, we calculated the water stress indicator in a different way from OECD method. The water stress indicator was calculated using data on the degree of water storage in agricultural water reservoirs because 87% of water for irrigation was taken from the agricultural water reservoirs. Water use technical efficiency was calculated as the reverse of the ratio of irrigation water to a standard water requirement of the paddy rice. The efficiency in 2001 was better than in 1990 and 1998. As for the economic efficiency for water use, we think that there are a lot of things to be taken into considerations to make a useful indicator to reflect socio-economic values of agricultural products resulted from the water use. Conclusively, site-specific, regional or meteorogical characteristics as in Korea were not considered in the calculation of water use indicators by methods suggested in OECD(Volume 3, 2001). So, it is needed to develop a new indicators for the indicators to be more widely applicable in the world.

• Tuberculosis and Respiratory Diseases
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• v.51 no.3
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• pp.248-259
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• 2001

Background : In diagnosis or monitor of the airway obstruction in bronchial asthma, the measurement of $FEV_1$ in the standard method because of its reproducibility and accuracy. But the measurement of peak expiratory flow(PEF) by peak flow meter is much simpler and easier than that of $FEV_1$ especially in children. Yet there have been still no data of the predicted normal values of PEF measured by peak flow meter in Korean children. This study was conducted to provide equations to predict the normal value of PEF and correlation between PEF and $FEV_1$ in healthy children. Method : PEF was measured by MiniWright peak flow meter, and the forced expiratory volume and the maximum expiratory flow volume curves were measured by Microspiro HI 501(Chest Co.) in 346 healthy children(age:5-16 years, 194 boys and 152 girls) without any respiratory symptoms during 2 weeks before the study. The regression equations for various ventilatory parameters according to age and/or height, and the regression equations of $FEV_1$ by PEF were derived. Results : 1. The regression equation for PEF(L/min) was: $12.6{\times}$age(year)+$3.4{\times}$height(cm)-263($R^2=0.85$) in boys, and $6{\times}$age(year)+$3.9{\times}$height(cm)-293($R^2=0.82$) in girls. 2. The value of FEFmax(L/sec) derived from the maximum expiratory flow volume curves was multiplied by 60 to compare with PEF(L/min), and PEF was faster by 125 L/min in boys and 118 L/min in girls, respectively. 3. The regression equation for $FEV_1$(ml) by PEF(L/min) was:$7{\times}$PEF-550($R^2=0.82$) in boys, and $5.8{\times}$PEF-146 ($R^2=0.81$) in girls, respectively. Conclusion : This study provides regression equations predicting the normal values of PEF by age and/or height in children. And the equations for $FEV_1$, a gold standard of ventilatory function, was predicted by PEF. So, in taking care of children with airway obstruction, PEF measured by the peak flow meter can provide useful information.

• Advances in pediatric surgery
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• v.8 no.2
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• pp.143-155
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• 2002

A survey on biliary atresia was made among 26 members of the Korean Association of Pediatric Surgeons. The members were required to complete a questionnaire and a case registration form for each patient during the twentyone-year period of 1980-2000. Three hundred and eighty patients were registered from 18 institutions. The average number of patients per surgeon was one to two every year. The male to female ratio was 1:1.3. The age of patients on diagnosis with biliary atresia was on average $65.4{\pm} 36.2$ days old. The national distribution was 32.8% in Seoul, 25.3% in Gyoungki-Do, 21.6% in Gyoungsang-Do, 9.27% in Choongchung-Do, etc. in order. The most common clinical presentation was jaundice (98.4%) and change of stool color (86.2%) was second. Two hundred eighty (74.7%) of 375 patients were operated by 80 days of age. Three hundred thirty six (9 1.9%) of 366 patients were operated on by the original Kasai procedure, and 305 (84.3%) of 362 patients were observed by bile-drainage postoperatively. The overall postoperative complication rate was 18.5% and the overall postoperative mortality rate was 6.8%. The associated anomalies were observed in 72 cases (22.5%). One hundred ninty five (64.7%) of 302 patients have been alive in follow-up and 49 (25.1%) have survived over 5 years without problem after operation. Ascending cholangitis, varices and ascites affected survival significantly, and the important long-term prognostic factor was the occurrence of complications.

• Radiation Oncology Journal
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• v.28 no.3
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• pp.117-124
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• 2010

Purpose: To analyze the postoperative radiotherapy results and prognostic factors in patients with WHO grade 3 and 4 gliomas. Materials and Methods: A total of 99 patients with malignant gliomas who underwent postoperative radiotherapy between 1988 and 2007 were enrolled in this study. Total resections, subtotal resections ($\geq$50%), partial resections (<50%), and biopsies were performed in 16, 38, 22, and 23 patients, respectively. In total there were 32, 63 and 4 WHO grade 3, 4, and unspecified high grade gliomas, respectively. The biologically equivalent dose was in the range of 18.6 to $83.3\;Gy_{10}$ (median dose, $72.2\;Gy_{10}$). We retrospectively analyzed survival rate, patterns of failure, prognostic factors, and adverse effects. Results: The median follow-up time was 11 months and there were 54 patients (54.5%) with local failure. The one and 2-year survival rates were 56.6% and 29.3%, respectively, and the median survival duration was 13 months. The one and 2-year progression-free survival rates (PFS) were 31.3% and 18.2%, respectively, and the median PFS was 7 months. The prognostic factors for overall survival were age (p=0.0001), surgical extents (subtotal resection, p=0.023; partial resection, p=0.009; biopsy only, p=0.002), and enhancement of tumor in postoperative imaging study (p=0.049). The factors affecting PFS were age (p=0.036), tumor enhancement of the postoperative imaging study (p=0.006). There were 3 patients with grade 3 and 4 side effects during and after radiotherapy. Conclusions: In addition to age and surgical extents, tumor enhancement of the postoperative imaging study was included in the prognostic factors. The most common relapse patterns were local failures and hence, additional studies are needed to improve local control rates.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.893-899
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• 2004

Method for sample preparation and quantitative analysis of 19 permitted and non-permitted synthetic colors in foods was developed based on reversed-phase ion-pairing high performance liquid chromatography. For color extraction of samples, deionized water was added, and pH was appropriately adjusted with 1% ammonia water. Any undissolved matters were extracted with 50% ethanol or 70% methanol. Lipid in snacks was first removed using n-hexane with centrifugation, water was added to extract colors, followed by clean-up and concentration using Sep-Pak $C_{18}$ cartridge. Recovery efficiencies at known concentrations of 19 standard food colors spiked into foods were in 90.3-97.9% range far soft drink, 79.2-101.9% for candy, 84.1-103.4% for jelly, 86.4-100.8% for chewing gum, 83.5-103.4% for ice cream, and 78.5-95.6% for snack.

• Tuberculosis and Respiratory Diseases
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• v.48 no.4
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• pp.438-447
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• 2000

Background : Transbronchial lung biopsy (TBLB) is a relatively simple and convenient procedure to obtain lung tissue from a patient with diffuse or localized lesion on chest radiographs, whose disease cannot be diagnosed through routine tests. The authors tried to evaluate the diagnostic value of TBLB, especially, the concordance between CT scan and TBLB with respect to the location of the lesion and diagnostic yield according to tumor-bronchus relationship. Method : We reviewed the medical records, plain chest films, and chest CT scans of 278 patients who underwent TBLB at Kyungpook National University Hospital between January 1996 and June 1998. Results : One hundred and sixteen (41.7 %) patients were diagnosed by TBLB. Diagnostic yield of TBLB of malignant tumors tended to be higher than that of benign diseases (64.7% versus 53.9%, p=0.09). Of primary lung cancers, TBLB was more diagnostic in adenocarcinoma and small-cell carcinoma than other cell types (p<0.01) and, of benign diseases, more diagnostic in tuberculosis than in non-tuberculous diseases (p<0.05). There was no significant difference in the diagnostic rate according to the location of the tumor. The diagnostic rate tended to increase with the size of tumor (p=0.06). The diagnootic rate of TBLB did not differ according to the pattern of lesion in benign diseases. However, in malignant diseases TBLB was more diagnostic in diffuse/multiple nodular lesions than in localized lesions(p<0.05). According to the tumor-bronchus relationship, TBLB was more diagnootic in type I/II groups than in other types. CT scan and TBLB showed a strong correlation with respect to the localization of the lesion (r=0.994, p<0.01). Conclusion : The above results show that TBLB is useful in the diagnosis of lung disease. CT scan and TBLB showed a strong correlation in determining the location of the lesion. Diagnostic yield of TBLB is higher in lesions with 'bronchus sign' (type I and II). TBLB and other diagnootic methods such as transthoracic needle aspiration are expected to complement one another in the diagnosis of lung diseases.