• International Journal of Advanced Culture Technology
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• 제7권4호
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• pp.40-48
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• 2019

Indoor gardens tailored to suit individual tastes offer a place to enjoy plants and to relax to city dwellers to relieve stress from city life. However, there are technical issues to build such indoor gardens. To offer solutions to technical issues, this study aims to analyze development phases of indoor garden-related technologies by studying available patents in detail. Also, the study aims to understand current status and future direction of technologies by examining technological trends for introduction of indoor gardens. Brainstorming method was used to understand technology trends and as a result, two groups were identified for technical features of indoor gardens: indoor greening technology and rest area for users. An analysis on selected patents showed that the number of patents increased until 2010 and declined gradually afterwards. Korea ranked the highest in the number of patents grant followed by USA, Japan and Europe. Similar order was observed with the number of patents granted by nationality of applicants. The number of patents granted by nationality was the highest for Korean nationals. For indoor greening technologies, patents related to structure from 2007 were mostly concentrated in the areas of irrigation control and environment control for plants and vegetation. For rest area related technologies, patent related to structure showed a repetitive pattern of increasing and decreasing, but overall, on downtrend. For further development and dissemination of indoor gardening technology, more R&D work is needed with focus on environmental control technology for designing suitable environment for both human and plant.

• Journal of Power Electronics
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• 제11권3호
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• pp.335-341
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• 2011

This paper presents an improved orientation strategy for energy-efficiency in photovoltaic (PV) panels. Conventionally, PV panels are tilted with the site's latitude angle or the difference between the latitude angle and the solar declination angle. A monthly-based orientation strategy has been proposed and analyzed in this study. The proposed strategy implies that the PV panels are tilted with the monthly-based angle that achieves the maximum incident radiation. Furthermore, the impact of using the proposed orientation strategy and three conventional strategies on the produced power and on the PV system design features has been investigated in detail. A Japanese city (Fukuoka) and an Egyptian city (Al-Kharijah) have been considered as locations for the PV power system installation. The results showed that the proposed strategy achieved an increase in the power produced from the PV power systems at the two different sites, and consequently the required solar cells area can be saved. Therefore, the cost of the PV power system components can be reduced including the solar cells area and the land area.

• Wind and Structures
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• 제17권4호
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• pp.419-433
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• 2013

This paper investigates the vertical profiles of horizontal mean wind speed and direction based on the synchronized measurements from a Doppler radar profiler and an anemometer during 16 tropical cyclones at a coastal site in Hong Kong. The speed profiles with both open sea and hilly exposures were found to follow the log-law below a height of 500 m. Above this height, there was an additional wind speed shear in the profile for hilly upwind terrain. The fitting parameters with both the power-law and the log-law varied with wind strength. The direction profiles were also sensitive to local terrain setups and surrounding topographic features. For a uniform open sea terrain, wind direction veered logarithmically with height from the surface level up to the free atmospheric altitude of about 1200 m. The accumulated veering angle within the whole boundary layer was observed to be $30^{\circ}$. Mean wind direction under other terrain conditions also increased logarithmically with height above 500 m with a trend of rougher exposures corresponding to lager veering angles. A number of empirical parameters for engineering applications were presented, including the speed adjustment factors, power exponents of speed profiles, and veering angle, etc. The objective of this study aims to provide useful information on boundary layer wind characteristics for wind-resistant design of high-rise structures in coastal areas.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.37-38
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• 2022

During the past decades, the corrosion of the steel rebar embedded in concrete structure surrounding marine environment is actually problematic and required the suitable preventive method. An eco-friendly corrosion inhibitor mix is investigated to stifle the active corrosion in comparison with other commercial corrosion inhibitors. The hybrid inhibitor enhances the corrosion resistance and the workability of concrete. However, it reduces the compressive strength slightly after 28-day-age. The electrochemical studies and mechanical studies are pointed out the corrosion resistance property, corrosion kinetics, and the mechanical properties of all concrete samples. H-3 is the optimum dose of hybrid inhbitor that meets the demand of both electrochemical property and mechanical property. It performs the noble features due to the formation of optimum amount of P-Zwitterions-(Cl)-Fe complex onto the steel rebar surface.

• 생명과학회지
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• 제27권3호
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• pp.275-282
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• 2017

부산지역 급성호흡기감염증으로 내원한 환자에서 호흡기바이러스 검사를 시행하여 아데노바이러스 및 보카바이러스의 특징적인 임상증상 및 유행양상을 알아보고자 하였다. 3,230명의 환자에서 총 1,485건(46.0%)의 호흡기바이러스가 검출되었고 이 중 아데노바이러스 257건(8.0%), 보카바이러스 68건(2.1%)을 확인하였다. 성별 발생양상은 남자가 여자보다 아데노바이러스, 보카바이러스로 인한 호흡기감염증에 취약하였으며, 모두 1~5세 연령군에서 높은 검출률을 보여 영 유아의 주요 감염요인임을 확인할 수 있었다. 주요 임상증상으로 아데노바이러스는 발열, 두통이 보카바이러스는 천명음이 통계적으로 유의하였다. 아형분석결과, 아데노바이러스는 1~6, 8형의 혈청형을 확인하였고 기존 분리주와 97% 이상의 상동성을 보였다. 연도별 유행 혈청형은 2011년 아데노바이러스 1형, 2012년 3형과 4형, 2013년에는 3형이 우점적으로 유행하였다. 아데노바이러스 3형의 경우, 대유행을 유발하는 아형으로 보인다. 보카바이러스는 모두 1형으로 나타났다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제3권6호
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• pp.597-611
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• 2009

With the advent of ubiquitous computing society, many advanced technologies have enabled wireless sensor networks which consist of small sensor nodes. However, the sensor nodes have limited computing resources such as small size memory, low battery life, short transmission range, and low computational capabilities. Thus, decreasing energy consumption is one of the most significant issues in wireless sensor networks. In addition, numerous applications for wireless sensor networks are recently spreading to various fields (health-care, surveillance, location tracking, unmanned monitoring, nuclear reactor control, crop harvesting control, u-city, building automation etc.). For many of them, supporting security functionalities is an indispensable feature. Especially in case wireless sensor networks should provide a sufficient variety of security functions, sensor nodes are required to have more powerful performance and more energy demanding features. In other words, simultaneously providing security features and saving energy faces a trade-off problem. This paper presents a novel energy-efficient security architecture in an IEEE 802.15.4-based wireless sensor network called the Hybrid Adaptive Security (HAS) framework in order to resolve the trade off issue between security and energy. Moreover, we present a performance analysis based on the experimental results and a real implementation model in order to verify the proposed approach.

• 한국농촌건축학회논문집
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• 제13권1호
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• pp.21-28
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• 2011

The main purpose of this study is to analyze construction of space through the investigation of the cases of school community library through Gangneung-si's life-learning project and the findings from the analysis could be summarized as below. Firstly, most space used for school community library has the size of two classes in school on average and locals use generally space for reference and learning at school community library. Secondly, the construction of space of school community library is categorized into one for book-returning, references, reading, group learning and information, and an audio-visual space is also used for group learning and reading. A space for book-returning has features based on the location of its entrance and a space for reading features stand-up and sitting-on space considering size and usability. And a space for group learning has the feature of space planning that makes it possible for local people to get library programs and seminars and a space for information shows its feature of space planning that uses the wall.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 학술대회 논문집 전문대학교육위원
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• pp.154-158
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• 2006

The switching-mode power converter has been widely used because of its features of high efficiency and small weight and size. These features are brought by the ON-OFF operation of semiconductor switching devices. However, this switching operation causes the surge and EMI(Electromagnetic Interference) which deteriorate the reliability of the converter themselves and entire electronic systems. This problem on the surge and noise is one of the most serious difficulties in AC-to-DC converter. Random Pulse Width Modulation (RPWM) is peformed by adding a random perturbation to switching instant while output-voltage regulation of converter is performed. RPWM method for reducing conducted EMI in single switch three phase discontinuous conduction mode boost converter is presented. The more white noise is injected, the more conducted EMI is reduced. But output-voltage is not sufficiently regulated. This is the reason why carrier frequency selection topology is proposed. In the case of carrier frequency selection, output-voltage of steady state and transient state is fully regulated. A RPWM control method was proposed in order to smooth the switching noise spectrum and reduce it's level. Experimental results are verified by converter operating at 300v/1kW with $5%{\sim}30%$ white noise input. Spectrum analysis is performed on the Phase current and the CM noise voltage. The former is measured with Current Probe and the latter is achieved with LISN, which are connected to the spectrum analyzer respectively.

• 한국생활과학회지
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• 제22권6호
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• pp.659-672
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• 2013

Nowadays, sports and outdoor market has been popular and expanding since the implementation of the five-day workweek and change of lifestyle. Outdoor clothing considered exclusive property of the middle-aged individuals in the past. Recently there is a drift towards having outdoor looking at the age of 10-20. The purpose of this study was to analyze the features of purchasing behaviors and demographics by each groups targeting middle school and high school students. The study was conducted with questionnaires towards people who live in the city of Busan and who have experiences of buying outdoor clothing. Data analysis was conducted via SPSS 18.0 with factor analysis, cluster analysis, ANOVA, cross tabulation, frequency analysis and Duncan's multiple range test. The results showed that there were five factors sought for outdoor wear benefits: Individuality/Fashion, Brand, Attractive appearance, Economic value, Comfort/Functional. Cluster analysis showed that there were four groups of outdoor wear benefits sought. Overall, the four groups were different in regard to purchasing behaviors and demographics. Based upon the results mentioned above, this study summarizes the key features of each group and can provide applicable suggestion for conducting strategic marketing activities.

• Clinical and Experimental Pediatrics
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• 제63권4호
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• pp.119-124
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• 2020

A cluster of severe pneumonia of unknown etiology in Wuhan City, Hubei province in China emerged in December 2019. A novel coronavirus named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was isolated from lower respiratory tract sample as the causative agent. The current outbreak of infections with SARS-CoV-2 is termed Coronavirus Disease 2019 (COVID-19) by the World Health Organization (WHO). COVID-19 rapidly spread into at least 114 countries and killed more than 4,000 people by March 11 2020. WHO officially declared COVID-19 a pandemic on March 11, 2020. There have been 2 novel coronavirus outbreaks in the past 2 decades. The outbreak of severe acute respiratory syndrome (SARS) in 2002-2003 caused by SARS-CoV had a case fatality rate of around 10% (8,098 confirmed cases and 774 deaths), while Middle East respiratory syndrome (MERS) caused by MERS-CoV killed 861 people out of a total 2,502 confirmed cases between 2012 and 2019. The purpose of this review is to summarize known-to-date information about SARS-CoV-2, transmission of SARS-CoV-2, and clinical features.