• The Plant Pathology Journal
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• 제24권2호
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• pp.131-142
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• 2008

Magnaporthe oryzae, the causal agent of the rice blast disease, poses a worldwide threat to stable rice production. The large-scale functional characterization of genes controlling the pathogenicity of M. oryzae is currently under way, but little is known about heat shock protein 40 (Hsp40) function in the rice blast fungus or any other filamentous plant pathogen. We identified 25 genes encoding putative Hsp40s in the genome of M. oryzae using a bioinformatic approach, which we designated M. oryzae heat shock protein forty (MHF 1-25). To elucidate the roles of these genes, we characterized the functions of MHF16 and MHF21, which encode type ill and type n Hsp40 proteins, respectively. MHF16 and MHF21 expression was not significantly induced by heat shock, but it was down-regulated by cold shock. Knockout mutants of these genes $({\Delta}$mhf16 and ${\Delta}$mhf21) were viable, but conidiation was severely reduced. Moreover, sectoring was observed in the ${\Delta}mhf16$ mutant when it was grown on oatmeal agar medium. Conidial germination, appressorium formation, and pathogenicity in rice were not significantly affected in the mutants. The defects in conidiation and colony morphology were fully complemented by reintroduction of wild type MHF16 and MHF21 alleles, respectively. These data indicate that MHF16 and MHF21 play important roles in conidiation in the rice blast fungus.

• 보존과학회지
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• 제32권3호
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• pp.437-448
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• 2016

전지구적으로 일어나는 기후변화에 대응하기 위해 20세기 말부터 선진국을 중심으로 기후변화에 의한 문화유산 취약성 평가와 대책 연구가 활발히 이루어져 관련 연구방법이 정립되고 방대한 기후자료와 손상예측 자료가 축적되었다. 우리나라는 관련된 정책연구가 다수 수행된 반면 여전히 과학적인 근거자료를 확보해야 하는 당면 과제가 남아있다. 한반도 미래 기후자료를 반영한 국내 석조유산의 미래 손상양상은 물리적, 화학적 및 생물학적 풍화 측면에서 복합적으로 변화할 가능성이 높으며, 이는 문화유산 보존 분야의 산업과 행정관리에도 영향을 미칠 것으로 전망된다. 앞으로 기후변화에 의한 석조유산의 영향 연구는 지역과 자료주기의 다운스케일을 통해 정밀화된 방향으로 진행되어야 한다. 이를 통해 손상유형과 지역별로 미래 환경에 취약한 석조유산을 가려내고 대응방안을 마련하는 것이 필요하다.

• 디자인학연구
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• 제11권3호
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• pp.35-44
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• 1998

자급제용 공중전화기가 급속도로 증가하고 있는 추세에서 소비자의 디자인 감성을 파악하는 것은 소비자의 개성추구 경향을 반영한 제품을 만드는 토대가 되며, 이를 통해 제품 경쟁력을 높일 수 있다. 본 연구는 이러한 배경을 바탕으로 자급제용 공중전화기에 대한 소비자 욕구(감성)를 정량적으로 측정하였다. 1차 도출된 168개의 감성어휘를 SD척도로 실시한 결과 35개의 감성어휘가 추출되었으며 이를 대상으로 SD척도 7단 구성을 이용하여 남녀 대학생 30명에게 기존 10개의 제품 이미지에 대한 설문조사를 시행하였다. 감성어휘의 요인들간의 상관성을 파악하기 위해 요인분석을 실시하였고, 분류를 위해 군집분석을 실시하였으며, 디자인요소와 감성어휘와의 상관관계를 예측하기 위해 판별분석을 실시하였다. 그 결과 감성어휘는 심미성, 기능성, 안전성의 3가지 요인으로 구분되었고, 디자인요소인 몸체, 핸드 셋, 다이얼 조립 판, 다이얼 버튼, 제어버튼, 칼라(몸체), 재질에 대해서 소비자가 느끼는 감성어휘와의 상관관계를 규명하다. 본 연구는 기존의 디자이너 개인의 감각에 의존하는 것보다 더 체계적이고 과학적으로 소비자의 욕구를 파악하여 소비자의 감성을 만족시키는 공중전화기 디자인의 개발에 도움이 되리라 본다.

• 한국가구학회지
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• 제18권2호
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• pp.91-99
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• 2007

Modernity which is superficial phenomenon set off the mass scale for mass consumption and provide uniformly artificial environment. But natural destruction, environment pollution, resources exhaustion and so on has been caused by this and now ecology is threatened by destruction and damage beyond the limitation and human beings survival is even threatened. Accordingly furniture development for environment preservation considered environment problem is the urgent real situation. Recent paradigm is the concept of Eco-design which is the green design possible to live together in symbiosis, and new types of alternative furniture are needed in Korea as well. 'Furniture for disassembly' is presented as new method for alternative furniture. Furniture for disassembly can be presented by mainly two directions. The first main characteristic is what is assembled by the use of woodworking joints technique as an assembly structure system without any hardware. The second is what is presented as the structure possible to be assembled by simple manual tools with hardware without any glue. The advantages of furniture for disassembly are environment preservation, space application, transportation efficiency and shapeliness. In manufacture method which is different from present furniture, the application of traditional truss technique which uses various types of custom-made and connection technique in case of assemble structure system without hardware is the typical differences. This assembly method expects not only interest induction about assembly and disassembly of diagram per sub materials but also the development of emotion, the improvement of collaboration, space perception ability and shape sense, the improvement of solid body structure insight and so on, when it use in the furniture for children with the application to many kinds of structure with BANGDOOSANJ (Wedged), JUMUGJANGBU (Dovetail) or NABIEUNJANG (Dovetail Keys) and so on.

• 한국산학기술학회논문지
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• 제13권12호
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• pp.5696-5703
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• 2012

본 연구는 자동차용 에어백 장치를 구성하고 있는 필터의 압력변화 특성을 해석하였다. 에어백 필터를 통한 압력 변화는 에어백을 부풀게 하는 기체의 압력에 직접적인 영향을 미친다. 그러나 현제 필터의 어느 설계인자가 압력변화에 얼마나 영향을 미치는지에 대한 정확한 기준이 불분명 하다. 또한 에어백 필터의 특성에서 압력 손실계수는 실험적 방법으로 평가하기에는 많은 어려움이 따른다. 이를 해결하기 위해서, 시뮬레이션 해석을 이용한 필터의 압력손실계수 해석방법을 제시하였다. 그러나, 일반적인 시뮬레이션 해석에서 에어백 필터와 같이 순간적으로 갑자기 증가하는 압력변화 해석은 불가능하다. 따라서, 보간법과 축척 축소방법을 적용하여 에어백 압력 변화 해석을 수행하였다. 또한, 에어백 필터의 압력손실계수에 대한 시뮬레이션 해석을 통하여 필터 설계에 대한 가이드 라인을 제시할 수 있었다.

• Wind and Structures
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• 제20권3호
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• pp.449-468
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• 2015

Current wind-resistance designs of large-scale indirect dry cooling towers (IDCTs) exclude an important factor: the influence of the ventilation rate for radiator shutter on wind loads on the outer surfaces of the tower shell. More seemingly overlooked aspects are the effects of various ventilation rates on the wind pressure distribution on the tower surfaces of two IDCTs, and the feature of the flow field around them. In order to investigate the effects of the radiator shutter ventilation rates on the aerodynamic interference between IDCTs, this paper established the numerical wind tunnel model based on the Computational Fluid Dynamic (CFD) technology, and analyzed the influences of various radiator shutter ventilation rates on the aerodynamic loads acting upon a single and two extra-large IDCTs during building, installation, and operation stages. Through the comparison with the results of physical wind tunnel test and different design codes, the results indicated that: the influence of the ventilation rate on the flow field and shape coefficients on the outer surface of a single IDCT is weak, and the curve of mean shape coefficients is close to the reference curve provided by the current design code. In a two-tower combination, the ventilation rate significantly affects the downwind surface of the front tower and the upwind surface of the back tower, and the larger positive pressure shifts down along the upwind surface of the back tower as the ventilation rate increases. The ventilation rate significantly influences the drag force coefficient of the back tower in a two-tower combination, the drag force coefficient increases with the ventilation rate and reaches the maximum in a building status of full ventilation, and the maximum drag coefficient is 11% greater than that with complete closure.

• Advances in environmental research
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• 제4권3호
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• pp.155-172
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• 2015

In this study, a complete set of recirculating cooling water system and the required instruments were built in a semi-industrial-scale and a 50 g/h ozone generation plant and a chlorine system were designed for cooling water treatment. Both chlorination and ozonation treatment methods were studied and the results were analyzed during two 45-days periods. The concentrations of ozone and chlorine in recirculating water were constant at 0.1 mg/lit and 0.6 mg/lit, respectively. In ozone treatment, by increasing the concentration cycle to 33%, the total water consumption decreased by 26% while 11.5% higher energy efficiency achieved thanks to a better elimination of bio-films. In case of Carbon Steel, the corrosion rate reached to 0.012 mm/yr and 0.025 mm/yr for the ozonation and chlorination processes, respectively. Furthermore, consumptions of the anti-corrosion and anti-sedimentation materials in the ozone cooling water treatment were reduced about 60% without using any oxidant and non-oxidant biocides. No significant changes in sediment load were seen in ozonation compared to chlorination. The Chemical Oxygen Demand of the blow-down in ozonation method decreased to one-sixth of that in the chlorination method. Moreover, the soluble iron and water turbidity in the ozonation method were reduced by 97.5% and 70%, respectively. Although no anaerobic bacteria were seen in the cooling water at the proper concentration range of ozone and chlorine, the aerobic bacteria in chlorine and ozone treatment methods were 900 and 200 CFU/ml, respectively. The results showed that the payback time for the ozone treatment is about 2.6 years.

• Structural Engineering and Mechanics
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• 제61권2호
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• pp.245-253
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• 2017

The increasing lack of good quality soils allowing the development of roadway, motorway, or railway networks, as well as large scale industrial facilities, necessitates the use of reinforcement techniques. Their aim is the improvement of the global performance of compressible soils, both in terms of settlement reduction and increase of the load bearing capacity. Among the various available techniques, the improvement of soils by incorporating vertical stiff piles appears to be a particularly appropriate solution, since it is easy to implement and does not require any substitution of significant soft soil volumes. The technique consists in driving a group of regularly spaced piles through a soft soil layer down to an underlying competent substratum. The surface load being thus transferred to this substratum by means of those reinforcing piles, which illustrates the case of a piled embankment. The differential settlements at the base of the embankment between the soft soil and the stiff piles lead to an "arching effect" in the embankment due to shearing mechanisms. This effect, which can be accentuated by the use of large pile caps, allows partial load transfer onto the pile, as well as surface settlement reduction, thus ensuring that the surface structure works properly. A technique for producing rigid piles has been developed to achieve in a single operation a rigid circular pile associated with a cone shaped head reversed on the place of a rigid circular pile. This technique has been used with success in a pile-supported road near Bourgoin-Jallieu (France). In this article, a numerical study based on this real case is proposed to highlight the functioning mode of this new technique in the case of industrial slabs.

• Journal of Multimedia Information System
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• 제1권1호
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• pp.67-75
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• 2014

Nowadays as video services grow rapidly, it is important for the service providers to provide customized services. Video ranking plays a key role for the service providers to attract the subscribers. In this paper we propose a weekly video ranking mechanism based on the quantified user engagement. The traditional QoE ranking mechanism is relatively subjective and usually is accomplished by grading, while QoS is relatively objective and is accomplished by analyzing the quality metrics. The goal of this paper is to establish a ranking mechanism which combines the both advantages of QoS and QoE according to the third-party data collection platform. We use data mining method to classify and analyze the collected data. In order to apply into the actual situation, we first group the videos and then use the regression tree and the decision tree (CART) to narrow down the number of them to a reasonable scale. After that we introduce the analytic hierarchy process (AHP) model and use Elo rating system to improve the fairness of our system. Questionnaire results verify that the proposed solution not only simplifies the computation but also increases the credibility of the system.

• 한국철도학회논문집
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• 제16권1호
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• pp.47-51
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• 2013

본 논문은 연약지반 쉴드 TBM 축소 모형실험을 통하여 슬러리에 의해 가해지는 막장 지보압의 변화에 따른 터널 막장면 안정성 변화 양상을 파악하고자 토피고에 따라 0.5D, 0.75D, 1.0D, 1.25D, 1.5D의 총 5개 Case에 대하여 모형실험을 수행하였으며, 이론적인 터널 막장면 지보압 및 모형실험으로 선정된 적정 지보압 값을 상호 비교하였다. 암반 쉴드 TBM과 달리 연약지반 쉴드 TBM의 경우 균질한 지반조건임에 따라 모형실험으로부터 산정된 적정 지보압이 터널 심도에 따른 막장면 토압 및 수압으로부터 이론적으로 산정된 막장압 범위($P_{min}{\leq}P_{slurry\;pressure}{\leq}P_{max}$)와 잘 일치하고 있음을 확인하였다.