• 한국전산유체공학회지
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• 제16권2호
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• pp.24-29
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• 2011

Immersed boundary lattice Boltzmann method has been applied to analyze the characteristics of the self-propelled fish motion swimming robot. The airfoil NACA0012 with caudal fin stroke model was considered to examine the characteristics. The foil in steady forward motion and a combination of steady-state harmonic deformation produces thrust through the formation of a flow downstream from the trailing edge. The harmonic motion of the foil causes unsteady shedding of vorticity from the trailing edge, while forming the vortices at the leading edge as well. The resultant thrust is developed by the pressure difference formed on the upper and lower surface of the airfoil. and the time averaged thrust coefficient increases as Re increase in the region of $Re{\leqq}700$. The suggested numerical method is suitable to develop the fish-motion model to control the swimming robot, however It would need to extend in 3D analysis to examine the higher Re and to determine the more detail mechanism of thrust production.

• 한국산업보건학회지
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• 제20권4호
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• pp.236-240
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• 2010

This study demonstrates the use of a chemical containing potassium superoxide (KO2) to convert carbon dioxide (CO$_2$) in air to oxygen (O$_2$). A oxygen generating closed-circuit SCBA (self contained breathing apparatus) removes carbon dioxide by a chemical reaction with potassium dioxide that consumes the carbon dioxide and produces oxygen. Considering the disasters, there is a need to develop strategies to enable the introduction of self-contained self rescuers (SCSR). The potassium superoxide reacts with the wears breath to produce oxygen and absorb carbon dioxide. If the respiration rate of a person is 5 MET (metabolic equivalent), to say 30 L/min, at disaster such as fire, mass of potassium superoxide was evaluated as 33.3 g with yield and safety factor. Four researchers tested on a laboratory treadmill breathing through SCSRs in a closed circuit, it appears useable for 9 minutes.

• 대한전자공학회논문지SD
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• 제44권12호
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• pp.85-92
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• 2007

메모리 설계 기술과 제조 공정의 발전에 따라, 고집적 메모리의 생산이 본격화 되었다. 이러한 메모리의 고집적화는 복잡하고 정밀한 설계와 제조 공정을 필요로 하기 때문에, 메모리 내에 더 많은 고장을 존재할 가능성을 낳았다. 이에 따라 메모리에서 발생하는 여러 고장을 분석하고 메모리를 수리하여 공정상의 문제를 수정하기 위해, BISR(Built-In Self-Repair) 회로의 중요성이 부각되고 있다. 본 논문에서는 주어진 예비 메모리를 효율적으로 사용하여 고장이 발생한 메모리를 효과적으로 수리할 수 있는 메모리 내장형 자체 수리 회로의 구조와 그 방법론에 대해서 소개하고자 한다. 제안하는 자체 수리 회로는 sign bit이라는 추가적인 저장 장치를 이용하여 메모리 수리를 수행한다. 이는 기존에 비해 좀 더 향상된 성능을 가지고 있다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2004년도 Annual Meeting of the Korean Society ofApplied Pharmacology
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• pp.18-34
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• 2004

This paper will review data obtained primarily from our preclinical investigations that show that exposure to stress has a significant impact on drug taking. Stress increases reward associated with psychomotor stimulants, possibly through a process similar to sensitization, and a growing clinical literature indicates that there is also a link between substance abuse and stress in human addicts. One explanation for the high concordance between stress-related disorders and drug addiction is the self-medication hypothesis, which suggests that a dually-diagnosed person often uses the abused substance to cope with tension associated with life stressors or to relieve symptoms of anxiety and depression resulting from a traumatic event. However, another characteristic of drug self-administration is that drug delivery and its subsequent effects on the HPA axis are under the direct control of the individual. This controlled activation of the HPA axis may result in the production of an internal state of arousal or stimulation that is actually sought by the individual (i.e., the sensation-seeking hypothesis). During abstinence, however, exposure to stressors or drug-associated cues can stimulate the HP A axis to remind the individual about the effects of the abused substance, thus producing craving and promoting relapse. Stress reduction, either alone or in combination with pharmacotherapies targeting the HPA axis may prove beneficial in reducing cravings and promoting abstinence in individuals seeking treatment for addiction. Of primary importance is to reduce the impact of cocaine-associated environmental stimuli on the HPA axis so that they no longer function as triggers for relapse.

• Journal of Microbiology and Biotechnology
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• 제29권12호
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• pp.1861-1872
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• 2019

In the present work, we isolated and identified Aspergillus sydowii NYKA 510 as the most potent laccase producer. Its medium constituents were optimized to produce the highest possible amount of laccase, which was after 7 days at 31℃ and pH 5.2. Banana peel and peptone excelled in inducing laccase production at concentrations of 15.1 and 2.60 g/l, respectively. Addition of copper sulfate elevated enzyme yield to 145%. The fungus was employed in a microbial fuel cell (MFC). The best performance was obtained at 2000 Ω achieving 0.76 V, 380 mAm^-2, 160 mWm^-2, and 0.4 W. A project to design a self-sufficient lighting unit was implemented by employing a system of 2 sets of 4 MFCs each, connected in series, for electricity generation. A scanning electron microscopy image of A. sydowii NYKA 510 was utilized in algorithmic form generation equations for the design. The mixed patterning and patterned customized mass approach were developed by the authors and chosen for application in the design.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.9-10
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• 2005

We report on the fabrication and characterization of self- and artificially-controlled ZnO nanostructures have been investigated to establish nanostructure blocks for ZnO-based nanoscale device application. Systematic realization of self- and artificially-controlled ZnO nanostructures on $SiO_2/Si$ substrates was proposed and successfully demonstrated utilizing metalorganic chemical vapor deposition (MOCVD) in addition with a focused ion beam (FIB) technique. Widely well-aligned two-dimensional ZnO nanodot arrays ($4{\sim}10^4$ nanodots of 130-nm diameter and 9-nm height over $150{\sim}150{\mu}m^2$ with a period of 750 nm) have been realized by MOCVD on $SiO_2/Si$ substrates patterned by FIB. A low-magnification FIB nanopatterning mode allowed the periodical nanopatterning of the substrates over a large area in a short processing time. Ga atoms incorporated into the surface areas of FIB-patterned nanoholes during FIB engraving were found to play an important role in the artificial control of ZnO, resulting in the production of ZnO nanodot arrays on the FIB-nanopatterned areas. The nanodots evolved into dot clusters and rods with increasing MOCVD growth time.

• 한국조리학회지
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• 제14권2호
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• pp.115-127
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• 2008

The purpose of this study is to validate the evaluation of stock, which has relation with self-esteem and career for the development of commercial stock. This study conducted a survey of purchasing attitudes & receptiveness in order to hold an accurate course for developing stock. According to the analysis, the results are as follows. It examined the cuisiniers of deluxe hotels who mainly use stock of Seoul and the capital region. A total of 350 samples were distributed and 289 samples were selected for the research. Statistical analysis of collected data executed frequency, percentage, average, reliability analysis, factor analysis using SPSSWIN 12.0 PC package programs. Making stock, cooking skills, cooking methods, quality of food ingredients and cooking recipes are important. Also, sensory characteristics such as color, odor, and taste should be considered. Career and self-esteem act on the purchase accommodation attitude of commercial stock. Commercial stock products more than 1,000 mL or 2,000 mL of liquid styles need packing of vacuum pack(vinyl). Based on the result of this study, we will make efficient use of research data for the development of commercial stock products and we will be able to improve conservation of taste with good quality by making by hand through standardization and mass production of traditional culinary skills.

• 한국지역사회생활과학회지
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• 제22권3호
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• pp.327-339
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• 2011

This study aims to investigate relationships between benefit sought and selection attributes of green tea consumers. For data collection, a total of 595 copies of questionnaires were collected by convenience sampling in the Seoul and Gyeonggi-do area. The data were analyzed by using SPSS 15.0. The factor analysis identified four dimensions of the benefit sought : health benefit, sensory, sociality, and self-esteem. Six dimensions of selection attributes were identified as manufacturing, design, sensory appeal, recommendation, utility and brand. The results of the canonical correlation analysis indicated that health benefit, sensory, sociality of benefit sought and manufacturing, design, sensory appeal, recommendation, utility, brand of selection attributes were highly correlated, and the self-esteem of benefit sought and recommendation of selection attribute were highly correlated. This means it is important to place an emphasis on safety production, package design, sensory characteristics, product description, utility and brand for consumers who seek health benefit, flavor and sociality. It is also important to place an emphasis on product description for consumers who pursue self-esteem benefits. Green tea marketers should consider benefit sought aspects as the most important factors affecting selection attributes on green tea purchasing.

• Computers and Concrete
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• 제20권4호
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• pp.461-468
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• 2017

With the increasing demand in the production of concrete, there is a need for adopting a feasible, economical and sustainable technique to fulfill practical requirements. Self-Compacting Concrete (SCC) is one such technique which addresses the concrete industry in providing eco-friendly and cost effective concrete. The objective of the present study is to develop a mix design for SCC with Crushed Rock Fines (CRF) as fine aggregate based on the plastic viscosity of the mix and validate the same for its fresh and hardened properties. Effect of plastic viscosity on the fresh and hardened properties of SCC is also addressed in the present study. SCC mixes are made with binary and ternary blends of Fly Ash (FA) and Ground Granulated Blast Slag (GGBS) with varying percentages as a partial replacement to Ordinary Portland Cement (OPC). The proposed mix design is validated successfully with the experimental investigations. The results obtained, indicated that the fresh properties are best achieved for SCC mix with ternary blend followed by binary blend with GGBS, Fly Ash and mix with pure OPC. It is also observed that the replacement of sand with 100% CRF resulted in a workable and cohesive mix.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.643-643
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• 2012

Increasing energy prices and growing concerns about global warming address the need to improve energy self-sufficiency in many industrial and municipal sectors. Wastewater treatment plants (WWTPs) are representative of energy-consuming facilities in Korea, accounting for 5% of national energy consumption. We present renewable energy technologies and energy self-sufficiency scenarios in a municipal WWTP ($30,000m^3d^{-1}$) located in Yongin, South Korea. By employing photovoltaics (PV, 135 kW), small hydropower turbine (10 kW), and thermal energy from treated effluent (25 RT: refrigeration ton) within the WWTP, a total of 142 tonne of oil equivalent (toe) of energy was estimated to be generated, accounting for $365ton\;CO_2\;yr^{-1}$ of greenhouse gas emission reduction. Core renewable technologies under consideration include 1) hybrid solar PV system consisting of fixed PV, dual-axis PV, and building integrated PV, 2) low-head small hydropower plant specifically designed for treated effluent, 3) effluent heat recovery system for heating and air conditioning. In addition to these core technologies, smart operation and management scheme will be presented for enhancing overall energy savings and distribution within the WWTP.