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This study introduced deterioration evaluation item and criteria that could be applied to industrial facilities withthe most widely used carbon steel pipe installed for ordinary piping (KSD 3507). Experimental industrial pipes were evaluatedwith pipe sectionalizing method combined with the established evaluation item and criteria to measure and manage semi-continuously for overall piping system. After applying outcomes from this study to a plant of incineration facility,a 42% saving in repairing and remodeling cost was achieved. Key words Pipe sectionalizing(배관 섹션화), Industrial pipes(산업시설 배관), Pipe deterioration(배관 노후도), Residual life(잔존 수명)†Corresponding author, E-mail: hkkmin1234@daum.net 1. 서 론 일반적으로 산업시설 배관의 설치길이는 건축물과는 달리 최소 수 킬로미터에서 많게는 수백 킬로미터에 이른다. 또한 설치지역이 중앙 집중적으로 설치된 건축설비분야와는 달리 배관은 복잡한 순환 구조로 산재되어 설치가 된다. 이러한 배관 설치의 특성은 배관의 유지관리 시 공간적, 시간적 제약을 주기에 배관 노후도 평가기법도 광범위한 지역의 배관 내부의 노후 상태를 쉽게 파악할 수 있도록 첨단 장비와 기술을 이용한 연구가 진행되고 있다. 그러나 이러한 연구노력도 원전 ․ 발전 및 석유 ․ 화학플랜트 등의 고온

This study aimed to evaluate the effect of oral iron supplementation in frequent donors in Korea, based solely on donation history.The hemoglobin (Hb) level, ferritin level, soluble transferrin receptor (sTfR), total iron binding capacity (TIBC), and transferrin saturation of frequent donors at high risk for iron deficiency were compared to those of first donors. The frequent donors took iron supplements for 4 weeks and the same tests were repeated after 2 and 4 weeks to evaluate their effects.A total of 53 male and 57 female frequent donors were recruited. After 4-week iron supplementation, among the men, the prevalence of a: low Hb level (13.0 g/dL) decreased from 25% to 2%; low ferritin level (15.0 ng/mL) decreased from 58% to 4%; iron deficient erythropoiesis (IDE) (log(sTfR/ferritin) ≥ 2.07) decreased from 77% to 33%. Among the women, the percentage of a: low Hb level (12.0 g/dL) decreased from 44% to 9%; low ferritin level decreased from 79% to 11%; IDE decreased from 95% to 47%. In total, 15 male (28.3%) and 29 female (56.9%) blood donors reported undesirable side effects related to iron supplementation. No serious adverse events were reported.Ferritin level, a reliable indicator of iron status, increased and IDE decreased significantly after four-week iron supplementation in the female, but not in the male, donor group, compared to those of control donors. Four-week oral iron supplement was not enough to restore iron storage level in the male donor group.

In general, no particularly well-established standards have been in place so far, for the method of evaluating thedeteriorated level of pipes and ducts of industrial facilities. For that reason, the evaluation depends upon various studieswhich are based on the analysis of the residual life, thickness thinning, closure rate, and scale thickness that measure a few specific positions of pipes. It also depends upon the expertise in business operation and the specific techniques conductedby the inspection companies and institutions. This research introduces the concept of measuring units per section and theselection method of measurement points per section. Furthermore, specific methodologies were developed to plan and analyzedeterioration level of industrial pipes and ducts by engineers and managers using a section map. Consequently, applyingthe outcomes from this study to the plant equipment of the incineration facility resulted in saving 42% of the repairing and remodeling cost.

Korean Abstract: 이 논문의 목적은 용적률 규제가 도시경제, 경제적 효율성 및 형평성에 미치는 영향을 분석하는 것이다. 2000년대 초반 서울시 주거지역에 용적률 강화사례의 편익과 비용을 계산하기 위해 연산가능 일반균형 토지이용-교통모형을 사용하였고 서울시 토지, 주택시장의 데이터를 활용하여 모형을 보정하였다. 분석결과 상한 용적률을 70% 수준으로 제한할 경우, 평균 가구의 실질소득이 1.92% 감소하는 것으로 나타났다. 또한 임차가구의 경우 실질소득이 13.8% 감소, 토지소유가구의 경우 6.1% 증가하는 것으로 분석되었다. 이를 바탕으로 주거지역 용적률 규제는 비효율적이면서 동시에 비형평적인 것으로 판단된다.English Abstract: The aim of the paper is to estimate effects of floor area ratio regulations on urban economy, economic efficiency and equity. We used land use-transportation CGE model to analyze the benefit and cost of the regulation and calibrated the model to the land and housing markets in Seoul to calculate the impact of tightening of Seoul’s floor area ratio regulations in 2000s. By restricting the level of maximum floor area ratio regulation to 70% of its value, we found that the real income of the average household decreased by 1.92%. The results also show that the real income of the renter group decreased by 13.8% and the one of the landowner group increased by 6.1%. Therefore, it seems that the floor area ratio regulation is inefficient and unfair regulation as well.

Background Despite screening blood donations with advanced technologies and improved donor screening, the risk of transfusion-transmitted infections persists. This risk is mainly due to blood donations collected during the window period. A precise estimate of the transfusion risk of viral infection will help to determine the effect of new and current safety measures and to prioritize and allocate limited resources. Therefore, we estimated the risk of transfusion-transmitted viral infection in blood donations collected in Korea from 2000 to 2010. Methods Blood donations collected at 16 blood centers were tested for HIV, HCV, and HBV to estimate the residual risk of transfusion-transmitted viral infection. The residual risk was calculated in two-year periods using the incidence/window model. The incidence rates for HIV/HCV and the confirmed positive rate for HIV/HCV in first-time and repeat donors were compared. Results The residual risks for HIV in 2004/2005 and 2009/2010 were 1 in 1,080,244 and 1 in 1,356,547, respectively. The risks for HCV in 2000/2001 and 2009/2010 were 1 in 81,431 and 1 in 2,984,415, and the risks for HBV in 2000/2001 and 2009/2010 were 1 in 45,891 and 1 in 43,666. These estimates indicate that the residual risks for HCV in Korea have declined 36.6-fold, and those for HIV and HBV have not improved significantly, compared to previous estimates. The odds ratios for HCV and HBV positivity in first-time donors compared to repeat donors were 11.8 and 19.6, respectively. Conclusions The residual risk of HCV declined over the last decade due to improved screening reagents, implementation of the nucleic acid amplification test, and tight application of strict donor selection procedures. Current residual risk estimates for HIV and HCV in Korea are extremely low, but the risk for HBV is still high; therefore, urgent measures should focus on decreasing the residual risk of HBV. Despite the introduction of more sensitive assays in blood screening, several other factors may influence the actual residual risk of transfusion-transmitted infection. A continuous monitoring of residual risk of transfusion-transmitted infection is crucial in managing blood safety.