• 공업화학
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• 제25권2호
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• pp.215-221
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• 2014

염기 처리에 의한 간단한 방법으로 합성된 $MnO_2$ (B-$MnO_2$)는 불균일 촉매시스템으로 호기성 조건에서 효과적인 아민 산화반응을 보여주었다. 이 B-$MnO_2$ 촉매는 다양한 종류의 방향족, 이원자 화합물, 비활성 지방족 등의 아민의 전환에 높은 활성과 선택성을 보여주었다. 이러한 산화반응은 온화한 온도($50^{\circ}C$)와 대기압의 공기 조건하에서 아민을 중간체인 이민으로 전환하고 자가 축합(self-condensation) 또는 산화적 탈수소화(oxidative dehydrogenation)을 통해 다이이민(diimine) 또는 나이트릴(nitrile)을 생성하였다. 사용된 촉매는 여과로 쉽게 분리할 수 있었고 5번 이상의 재사용 실험에서도 일정이상의 높은 수율을 보여주었다. 따라서 B-$MnO_2$는 아민 산화반응을 통해 이민과 나이트릴을 얻음에 있어 경제적으로나 환경친환적으로 효과적인 면을 보여 줌으로써, 그린화학(green chemistry)의 목적에 적합하다.

• 대한임상검사과학회지
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• 제36권2호
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• pp.121-126
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• 2004

The primary goal of six sigma is to improve patient satisfaction, and thereby profitability, by reducing and eliminating defects. Defects may be related to any aspect of customer satisfaction: high product quality, schedule adherence, cost minimization, process capability indices, defects per unit, and yield. Many six sigma metrics can be mathematically related to the others. Literally, six means six standard deviations from the mean or median value. As applied to quality metrics, the term indicates that failures are at least six standard deviations from the mean or norm. This would mean about 3.4 failures per million opportunities for failure. The objective of six sigma quality is to reduce process output variation so that on a long term basis, which is the customer's aggregate experience with our process over time, this will result in no more than 3.4 defect Parts Per Million(PPM) opportunities (or 3.4 Defects Per Million Opportunities. For a process with only one specification limit (upper or lower), this results in six process standard deviations between the mean of the process and the customer's specification limit (hence, 6 Sigma). The results of applicative six sigma experiment studied on 18 items TP, ALB, T.B, ALP, AST, ALT, CL, CK, LD, K, Na, CRE, BUN, T.C, GLU, AML, CA tests in clinical chemistry were follows. Assessment of process performance fits within six sigma tolerance limits were TP, ALB, T.B, ALP, AST, ALT, CL, CK, LD, K, Na, CRE, BUN, T.C, GLU, AML, CA with 72.2%, items that fit within five sigma limits were total bilirubin, chloride and sodium were 3 sigma. We were sure that the goal of six sigma would reduce test variation in the process.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권4호
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• pp.1406-1423
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• 2014

Multi-mode device which combines multiple access technologies into a device will offer more cost-effective solution than a sole access implementation. Its concurrent multipath transfer (CMT) technology can transmit media flows over multiple end-to-end paths simultaneously, which is essential to select at least two paths from all available paths. At real networks, different paths are likely to overlap each other and even share bottleneck, which can weaken the path diversity gained through CMT. Spurred by this observation, it is necessary to select multiple independent paths as much as possible to avoid underlying shared bottleneck between topologically joint paths. Recent research in this context has shown that different paths with shared bottleneck can weaken the path diversity gained through CMT. In our earlier work, a grouping-based multipath selection (GMS) mechanism is introduced and developed. However, how to estimating the selection is still to be resolved. In this paper, we firstly introduce a Selection Correctness Index (SCI) to evaluate the correctness of selection results in actual CMT experiment. Therefore, this metric is helpful to discuss and validate the accuracy of the output paths. From extensive experiments with a realized prototype, the proposed scheme provides better evaluation tool and criterion in various network conditions.

• 한국작물학회지
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• 제48권1호
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• pp.1-7
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• 2003

In spite water direct seeding cultivation of rice has advantages in terms of laborsaving and cost-down, it demonstrates uneven seedling establishment and difficult weed management. To select an applicable mat for mulching system of water seeded rice, weed occurrence, growth and yield performances of rice, and soil temperature were evaluated in several kinds of biodegradable mulching material. Field studies were conducted at the experimental farm of National Crop Experiment Station in 1999 and 2000. Among the mats tested in 1999, Safer-mat had the greatest effect on inhibiting weed occurrence and Lawn-mat demonstrated the least efficacy of weed control (EWC) value. In Safer-mat treatment, Ludwigia prostrata was the dominant weed species but Echinochloa crus-galli was not observed. Different kinds of mulching material from the mats studied in 1999 were tested in 2000. Biodegradable polyester (PES) coated on the recycled paper for newspaper press (RP) treatments showed similar or higher EWC values than non-mulched broadcast seed rice with 2 times of herbicide application (BC-herbicide) and Safer-mat that was the most effective mat on preventing weed appearance in 1999. Immediately after mat mulching on the surface of paddy soil, five pregerminated rice seeds were manually sown in each 3cm-hole formerly punctured at 30${\times}$14 cm spacing in 2000. All the 3 kinds of mulching material tested in 2000 had better seedling stand than BC-herbicide treatment. Rice yield in PES coated with 10 thickness on RP (PES10 $\mu\textrm{m}$＋RP) was a little higher than in BC-herbicide treatment but the former produced less panicles in unit land area than the latter. PES10 $\mu\textrm{m}$＋RP demonstrated a great effect on raising soil surface temperature than non-mulching treatment throughout the period of seedling establishment.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2008년도 춘계학술발표대회 논문집
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• pp.203-208
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• 2008

The purpose of the study is to establish the concept of residential standard, and at the same time to investigate the area of the minimum residential standard in the countries of the world through the preceding studies. In addition, it also aims at establishing the objective residential standard by comparing the residential standard of Korea with that of foreign countries, examining the problems and finding out the matters to be improved through the comparison of the residential standard in advanced countries with the minimum residential standard of Korea. The standard residential area, derived from the process of examining the minimum residential standard, will be used as the basic material for the calculation of the reasonable area in the surface plan for the study of low-cost housing development. The method of the study is to establish the concept of residential standard and at the same time to find out the problems in the minimum residential standard of Korea and improvement methods through the comparison of the residential standards in other countries. As the result of the studies focused on the area among the residential standards, it is found out that the Korea's residential area per capita is established as the least in comparison with that of advanced countries. The real area decided depending on the size of social space suitable for living can play a role in improving the degree of satisfaction in the person's living in the residential area. Therefore, it is urgently necessary to make a depth study on the surface area of the minimum residential standard, and it is also required to propose the residential standard and directions for the improvement of the qualitative level rather the quantitative expansion of residential structures.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권5호
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• pp.355-361
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• 2000

A recycling reactor system operated under sequential anoxic and oxic conditions for the treatment of swine wastewater has been developed, in which piggery slurry is fermentatively and aerobically treated and then part of the effluent is recycled to the pigsty. This system significantly removes offensive smells (at both the pigsty and the treatment plant), BOD and others, and may be cost effective for small-scale farms. The most dominant heterotrophic were, in order, Alcaligenes faecalis, Brevundimonas diminuta and Streptococcus sp., while lactic acid bacteria were dominantly observed in the anoxic tank. We propose a novel monitoring system for a recycling piggery slurry treatment system through the use of neural networks. In this study, we tried to model the treatment process for each tank in the system (influent, fermentation, aeration, first sedimentation and fourth sedimentation tanks) based upon the population densities of the heterotrophic and lactic acid bacteria. Principal component analysis(PCA) was first applied to identify a relationship between input and output. The input would be microbial densities and the treatment parameters, such as population densities of heterotrophic and lactic acid bacteria, suspended solids(SS), COD, NH$_4$(sup)+-N, ortho-phosphorus (o-P), and total-phosphorus (T-P). then multi-layer neural networks were employed to model the treatment process for each tank. PCA filtration of the input data as microbial densities was found to facilitate the modeling procedure for the system monitoring even with a relatively lower number of imput. Neural network independently trained for each treatment tank and their subsequent combined data analysis allowed a successful prediction of the treatment system for at least two days.

• KIEAE Journal
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• 제14권3호
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• pp.5-13
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• 2014

This paper introduces emergy(spelled with "m") that is a new environmental indicator in architecture, aiming to clarify conflicting claims of building design components in the process of energy-retrofit. Much of design practitioners' attention on low energy use in operational phases, may simply shift the lowered environmental impact within the building boundary to large consumption of energy in another area. Specifically, building energy reduction strategies without a holistic view starting from natural formation, may lead to the depletion of non-renewable geobiological sources (e.g. minerals, fossil fuels, etc.), which leaves a building with an isolated energy-efficient object. Therefore, to overcome the narrow outlook, this research discusses the total ecological impact of a building which embraces all process energy as well as environmental cost represented by emergy. A case study has been conducted to explore emergy-driven design work. In comparison with operational energy-driven scenarios, the results elucidate how energy and emergy-oriented decision-making bring about different design results, and quantify building components' emergy contribution in the end. An average-size ($101.9m^2$) single family house located in South Korea was sampled as a benchmark case, and the analysis of energy and material use was conducted for establishment of the baseline. Adoption of the small building is effective for the goal of study since this research intends to measure environmental impact according to variation of passive design elements (windows size, building orientation, wall materials) with new metric (emergy) regardless of mechanical systems. Performance simulations of operational energy were developed and analyzed separately from the calculation of emergy magnitudes in building construction, and then the total emergy demand of each proposed design was evaluated. Emergy synthesis results verify that the least operational energy scenario requires greater investment in indirect energy in construction, which clearly reveals that efficiency gains are likely to be overwhelmed by increment of material flows. This result places importance on consideration of indirect energy use underscoring necessity of emergy evaluation towards the environment-friendly building in broader sense.

• 한국통신학회논문지
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• 제35권11B호
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• pp.1596-1606
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• 2010

본 논문에서는 산재-부분-제한영역 파장 변환 방식의 파장분할다중화 광통신망의 불통 확률을 정확하게 계산할 수 있는 수학적 성능분석 모형을 제안하고, 이를 기반으로 파장 변환기를 효율적으로 배치하는 파장 변환기 배치 알고리듬을 제시한다. 제안하는 성능분석 모형은 파장 변환기의 제한된 파장 변환 영역으로 발생하는 영역 불통(Range Blocking)과 파장 변환기의 개수 제약으로 발생하는 용량 불통(Capacity Blocking)을 이론적으로 도출하는 최초의 성능분석 모형이다. 유럽 광통신망에서 수행한 시뮬레이션 결과를 통해 제안하는 성능분석 모형이 광통신망의 불통확률을 정확히 예측함을 보인다. 또한, 기존에 알려진 산재 파장 변환 방식, 부분 파장 변환 방식, 또는 제한영역 파장 변환 방식들과 비교할 때, 이들을 효율적으로 결합한 산재-부분-제한영역 파장 변환 방식이 최소의 파장 변환 비용으로 주어진 광통신망의 불통 성능을 달성할 수 있음을 보인다.

• KDI Journal of Economic Policy
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• 제35권2호
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• pp.133-166
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• 2013

본 논문은 2008년 6월~2011년 11월 기간 동안 우리나라 주식형 펀드의 자료를 이용하여 소프트달러(위탁매매수수료)와 펀드 특성 사이의 관계 및 위탁매매수수료와 투자수익률 사이의 관계에 대한 분석을 수행하였다. 분석 결과, 운용보수 및 판매보수는 위탁매매수수료와 음(-)의 관계를 가지는 것으로 확인되었는데, 이는 투자자가 상대적으로 명확하게 인지할 수 있는 운용보수 및 판매보수 수준을 높이기보다는 숨겨진 비용인 위탁매매수수료를 통해 간접적으로 보상이 이루어짐을 시사한다. 한편, 위탁매매수수료와 펀드성과 사이의 관계를 살펴본 결과, 위탁매매수수료가 높을수록 현재의 성과와 음(-)의 관계를 가지며, 단기적으로 미래의 성과를 제고하는 데 기여하지 못하는 것으로 확인되었다. 이러한 분석 결과는 투자자와 운용사의 이해상충의 완화와 대리인 문제의 효과적인 통제를 위한 제도 정비의 필요성을 시사하는 것으로 생각된다.

• 한국전자파학회논문지
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• 제11권2호
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• pp.294-301
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• 2000

RF(radio frequency) 시스템의 송신탄을 설계할 때 고려해야 할 중요한 요소 중의 하나인 EMI(Electro magnetic interference)의 규격시험에서 항상 문제시되는 것이 송신기의 출력 스펙트럼에서 나타나는 불요 신호(Spurious interference) 이다. 이 불요 성분들 중 특히 문제가 되고 있는 것이 국부발진기(LO; Local oscillator)로부터 누설되는 LOL(Local oscillator leakage) 성분이다. 이 LOL성분은 국부발진기에서 누설(leakage)되어 RF단의 증폭기를 통하여 증폭되어 최종 출력에서 매우 높은 선호의 크기로 나타난다. 일반적으로 LOL을 제거하기 위해 서 너치필터(Notch filter) 또는 대역통과필터 (Band pass filter)를 사용해왔다. 본 논문에서는 국부발진기로부터 누설되는 불요 성분, 즉 LOL성분을 제거하는 방법으로 LOL과 동일한 크기를 가지고 위상 차이가 $180^{\circ}$인 신호를 국부발전기의 출력에서 만들어 믹서( Mixer)의 출력단에 더함으로써 LOL성분을 효과적으로 제거한다. 본 방 식을 무선랜(WLAN; Wireless 1$\infty$al area network) 시스템에 적용한 결과. 기존의 방식보다 30 dB 이상 LO 누설선호플 감쇄시킬 수 있었다 또한 본 방식은 RF 시스댐을 소형화 및 MMIC(Monolithic microwave integrated C circuit)화 할 경우 종전의 방법보다 효과적일 것으로 기대된다.