In this study, the effect of milling time on the microstructure and phase transformation behaviors of Ni-12 wt.%B powders was investigated using vibratory ball milling process. X-ray diffraction patterns showed that the phase transformation of mixed Ni-B elemental powder occurred after 50 hours of milling, with a formation of nickel boride phases. Through the study of microstructures in mechanical alloying process, it was considered that ball milling strongly accelerates solid-state diffusions of the Ni and B atoms during mechanical alloying process. The results of X-ray photoelectron spectroscopy showed that most of B atoms in the powder were linked to Ni with a formation of nickel boride phases after 200 hours of milling. It was finally concluded that mechanical alloying using ball milling process is feasible to synthesize fine and uniform nickel boride powders.

본 연구는 연속철근 콘크리트 포장(CRCP: Continuously reinforced concrete pavement)에서 단부 앵커러그 유무에 따른 종방향 변위 비교를 통해 앵커러그의 필요성을 분석하고 내부 수평균열의 수직방향 변위 측정을 통해 이러한 균열이 CRCP의 공용성에 미치는 영향을 분석하기 위하여 수행되었다. 앵커러그 구간 절단 전 거동 측정은 6월 중에 12일간 계측하였으며, 앵커 러그 구간 절단 후의 측정은 절단 시 슬래브에 급격히 발생하는 변위가 사라진 이후 8월 중에 14일 동안 계측하였다. 이와 같은 단기간의 계측 결과 CRCP 단부의 종방향 변위는 앵커러그가 설치되어 있는 경우에는 모든 위치에서 일일 변위 변화가 0.1mm 이내로 종방향 거동이 거의 발생하지 않았다. 단부에 앵커러그가 설치되지 않은 경우에는 변위가 자유 단부 부근에서만 주로 발생하며 종방향 변위 변화가 작아서 팽창줄눈으로 처리하여도 적절할 것으로 예측되었으나, 향후 추가연구에 의해 사계절 온도변화에 따른 단부의 거동을 확인할 필요가 있을 것으로 판단된다. 내부 수평균열은 거동 측정 결과 거의 비활성균열이며 전체적인 슬래브의 수직변위에 영향을 미치지 않았다. 따라서 수평균열이 슬래브를 상하로 분리시켜 CRCP의 구조적인 성능 및 공용성의 저하를 유발하지는 않을 것으로 분석되었다.

The purpose of this study was to find discover the effects of self-efficacy and self-esteem on the appearance management behavior of female college students. As for the study method, questionnaire survey sheets on general traits like age, grade year, major and management cost, sense of self-efficacy, self-esteem, and appearance management behavior were distributed to female college students. The responses were measured based on a 5-points Likert scale. The results of this study are as follow: One’s sense of social self-efficacy and self-esteem were both found to affect appearance management behavior significantly. In other words, the greater one’s sense of social self-efficacy, which represents one's sense of confidence in inter-personal relations, the greater one’s appearance management behaviors to enhance her own value. Furthermore, the greater one’s self-esteem(the way one feels positively about oneself), the greater one’s appearance management behaviors. As a result, it can be judged that the more an individual wants to act more capable in different contexts, the more she tries to make up for her own disadvantage. To highlight her own advantages for the sake of greater positive social activities and inter-personal relation, the more she takes to improve her image through appearance management behaviors. It is anticipated that such an examination of appearance management behavior, sense of self-efficacy and self-esteem among female college students will serve as useful data for appearance-related industries by enabling them to properly under stand their clientele’s psychological traits.

The purpose of this study was to investigate the snack and beverage intake patterns of students by body mass index groups (BMI 〈18.5, 18.5-23, 23-30, ≥30). Questionnaires were completed by 1381 high school students in Seoul, Incheon, and Gyeonggi-do, the area of Korea's capital region. There were no significant differences in skipping meals for overweight (BMI 23-30 and ≥30) or under-nourished (BMI 〈18.5) students. Girls skipped dinner more frequently than boys. Boys and girls both preferred meat and disliked fish regardless of BMI. Girls with BMI 23-30 disliked vegetables. Boys and girls would rather have crackers, candies, and chocolates than potatoes as snacks regardless of BMI. Obese boys (BMI ≥30) preferred flour-based food, fast food, and other food as snacks. Girls liked fruits more than boys. Snacks were eaten 2-3 times per week, when students were hungry or bored. There were no significant differences in the frequency or reasons (habitual, stressed) for snack consumption by BMI. Girls liked juice more than boys did, and boys preferred soda water more than girls did. Both the under-nourished (BMI 〈18.5) boy and girl groups had more juice than the overweight (BMI 23-30 and ≥30) groups. Obese (BMI ≥30) boys did not more drink soda water than other BMI groups. The under-nourished (BMI 〈18.5) boy group had more soda water than the normal (BMI 18.5-23) and overweight (BMI 23-30) groups. Girls in the overweight (BMI 23-30) group had 2 more cups of soda water a day than the normal group (BMI 18.5-23). Therefore, skipping meals and beverage intake patterns might influence BMI.

Six plant essential oils, vanillin, and their mixtures were tested for repellent activities against a dengue virus vector mosquito, Aedes aegypti. Their repellency was verified with two conditions: different doses and an addition of vanillin. Among the plant essential oils, lemongrass, lemoneucalyptus and xanthoxylum oils were selected as the potential oils for tertiary mixtures. In bioassays using tertiary mixtures with two essential oils with vanillin, the composition of 1:3:1 (v/v/w) consisted of lemongrass oil, xanthoxylum oil and vanillin provided 270 min-CPT. As a practical application into spatial repellent, the mixture of 1:1:1 formulation containing lemongrass oil, xanthoxylum oil, and vanillin (v/v/w) was enclosed into the Viscopearl, porous cellulose beads that provide gradual release of volatile compounds. We composed this Viscopearl into a module and installed into the air conditioner. Apparently, repellent activity was shown that average repellency of 83.5% was observed for an hour through the chamber test. We confirmed via GC-chromatogram that linalool, geraniol, citral and vanillin were the main compounds of our oil mixture. Our study indicates that personal repellents were possibility applicable to spatial repellents.

Historically the rise of contagious diseases and epidemics has been mainly caused by lack of food safety knowledge and negligence in personal hygiene. Food poisoning is an example that have been caused by lack of proper knowledge in food safety and personal hygiene. In order to prove this hypothesis, our team distributed a total of 225 survey sheets to middle school students. Survey questions mainly focused on the students' food safety knowledge, personal hygiene and regular dietary habits. We used 12 items to determine the stages of change in teenagers and divided into 3 stages of change: precontemplation stage (poor problem recognition), contemplation and preparation stage (some problem recognition), and action stage. Out of the 225 students surveyed, 105(47.1%) were male and 118 (52.9%) were female; 44.0% were in 7th grade, 33.0% in 8th grade, and 24.0% in 9th grade. In stages of change model, 3.8% were classified in pre-contemplation stage, 31.1% in preparation stage, and 65.1% in action stage. The awareness of the significance of food safety has a strong positive correlation with the stages of change food safety behavior (P<0.001), which suggesting our questionnaires regarding stages of change and food safety behavior were quite credential. Stages of change were also correlated with the consumption of unsanitary foods (P<0.01) and with the frequent hand washing (P<0.05). The stages of change showed a positive correlation with the food safety knowledge level (P<0.05). The four questions (out of 10) with the least percentage of correct answers were questions about the meaning of Norovirus (23.6%), the meaning of expiration date (43.6%), the meaning of food poisoning (36.4%), and proper food-handling (36.0%).

본 논문은 노후교량바닥판 대체용으로서 하이브리드 GFRP-강재 바닥판의 휨거동을 구조적 거동특성을 기술하고 있 다. 하이브리드 GFRP-강재 바닥판의 구조적 특성을 조사하기 위해 정적하중의 실험적 연구를 수행하였다. 하이브 리드 바닥판의 파괴모드는 초기항복을 지나서 연성거동을 나타내었다. 결과는 유한요소프로그램 ANSYS의 값과 비 교하였다. 제안된 하이브리드 바닥판이 교량적용에 유용함을 확인하였다. 하이브리드 바닥판의 두께는 유사한 휨 강성을 갖는 완전복합신소재 바닥판께와 비교하였을 때 감소될 수 있었다.

In order to improve the weak mechanical properties of cast Mg alloys, Mg- (at%) alloy powders were synthesized using gas atomization, a typical rapid solidification process. The powders consist of fine dendrite structures less than 3 in arm spacing. In order to fabricate a bulk form, the Mg powders were compacted using magnetic pulse compaction (MPC) under various processing parameters of pressure and temperature. The effects of the processing parameters on the microstructure and mechanical properties were systematically investigated.

The scope of this work investigates the relationship between the amount of oxygen-functional groups and hydrogen adsorption capacity with different concentrations of phosphoric acid. The amount of oxygen-functional groups of activated carbons (ACs) is characterized by X-ray photoelectron spectroscopy. The effects of chemical treatments on the pore structures of ACs are investigated by N2/77 K adsorption isotherms. The hydrogen adsorption capacity is measured by H2 isothermal adsorption at 298 K and 100 bar. In the results, the specific surface area and pore volume slightly decreased with the chemical treatments due to the pore collapsing behaviors, but the hydrogen storage capacity was increased by the oxygen-functional group characteristics of AC surfaces, resulting from enhanced electron acceptor-donor interaction at interfaces.

본 연구는 웃음요법이 아동의 스트레스 대처행동 향상을 위해 어떤 영향을 미치는지를 알아보기 위하여, 서울시 중랑구의 ○○지역아동센터를 이용하는 4학년에서 6학년까지의 아동 19명을 대상으로 웃음요법 프로그램을 진행하였다. 프로그램 참여 아동 중 설문조사에 응답이 가능한 12명에 대해 스트레스 대처행동에 대한 사전․사후 검사를 진행하였으며, 본 연구를 통해 사용한 웃음요법 프로그램이 아동의 스트레스 대처행동에 효과가 있을 확인하였다. 이러한 연구결과는 본 연구에 활용한 웃음요법이 스트레스 대처행동을 향상시키는 프로그램이기에, 아동을 지도하는 기관에서 적극 활용한다면, 부적응 행동을 보이거나 의사소통에 어려움을 겪는 아동들의 불안한 마음을 진정시킬 뿐만 아니라 스트레스 해소 및 이에 대한 대처기술을 증진시키고 더불어 자존감 향상에도 유용하게 이용될 수 있음을 알려준다.

EMT-3D 모델을 사용하여 내분비계 장애물질인 Dioxins를 대상으로 울산만 에서의 적용성을 검토하였으며 민감도 분석 및 오염부하에 대한 해역의 응답성 분석을 수행하여 영향인자를 판별하고 대안에 따른 영향을 평가하였다. 대상해역의 실측치와 모델의 계산치를 비교한 결과 상관계수(R)값은 0.7951, 결정계수(R2) 값은 0.6265로 나타나 계산치가 비교적 잘 재현된 것으로 사료된다. 민감도 분석을 실행한 결과 수층의 용존 Dioxins와 입자성 유기물질내 Dioxins의 경우 분배계수와 침강속도의 순으로 영향이 큰 것으로 나타났으며, 식물플랑크톤 체내 Dioxins의 경우 생물농축계수의 증감에 따른 농도변화가 가장 큰 것으로 나타나 이들 계수에 대한 정밀한 고찰이 필요할 것으로 사료된다. 하천 및 대기로부터 유입되는 오염부하 저감에 따른 해역의 용존 Dioxins 및 입자성 유기물질내 Dioxins의 응답성을 평가하였다.

본 연구는 하이브리드 FRP로 보강된 철근 콘크리트 보의 구조거동 예측을 목표로 구조해석을 수행하여 기존에 발 표된 실험 연구 데이터와 비교하였다. 보다 정확한 구조해석을 위하여 현존하는 다양한 부착강도 모델을 검토한 후, 이 중 콘크리트 피복분리를 예측하는 Teng and Yao model과 FRP 탈락 현상을 예측할 수 있는 Smith and Teng model을 유한요소 해석 모델에 포함시켰다. 비선형 재료 및 형상 역시 구조해석 모델에 포함되었으며 이렇게 해석 된 결과는 실험결과와 비교하여 유사한 경향을 나타냈다. 그러나 다양한 하이브리드 FRP로 보강한 철근 콘크리트 보의 파괴모드를 보다 정확하게 예측하기 위하여 현존하는 수치식의 수정 및 도입이 필요하다.

Aphids feed on host plants by penetrating the stems or leaves with stylets. The feeding behavior of aphids consists of probing, penetration, salivation, and sap ingestion. To assess the effects of sound on feeding behavior, we monitored the stylet activity of the green peach aphid, Myzus persicae (Sulzer), using electrical penetration graph (EPG). The use of EPG was critical for determining the stage, frequency, and duration of feeding in aphids. We played back three acoustic stimuli of sine waves with frequencies of 100, 1000, and 5000 Hz to adult aphids. In the sound treatment group, the frequencies of probing, penetration, and salivation increased, whereas the duration of sap ingestion decreased. The results of EPG revealed that the acoustic stimuli may restrict aphid feeding by inhibiting sap ingestion.

The green peach aphid, Myzus persicae (Sulzer), is one of the most important insect pests in the world. We have explored the possibility of using sounds as a control agent in this species. Sine waves with four different frequencies (100, 500, 1000, 5000 Hz) were used as acoustic stimuli in the playback experiments. As a behavioral bioassay, we recorded honey dew production (HDP), wagging, and walking. HDP occurs regularly at each stage of nymphal and adult periods, and the rate of HDP may indicate a degree of food consumption. Aphids conduct wagging to determine a host plant or to find a feeding site. Walking may be regarded as dispersal. All acoustic stimuli significantly reduced the rates of HDP and increased the rates of wagging. There were no significant effect of acoustic stimuli on walking. Based on the bioassay, the acoustic stimulus with 5000 Hz seemed to be the most effective on inhibiting feeding behavior of this aphid species at an individual level.

The fiber reinforced polymer (FRP) strengthening is significantly effective for enhancing the performances of concrete to the high strain rate loadings. However, the FRP retrofitted concrete members show different behaviors comparing to quasi-static cases. This study presents experimental observation on behaviors of meso-scale concrete members retrofitted with FRP sheets under low-velocity drop-weight impact loadings. Concrete specimens with the dimensions of 100×100×400 mm were fabricated and various FRP sheets were attached. The specimens with a reinforced bottom surface and the doubly reinforced specimens showed much higher energy absorptions. Also, reinforced concrete (RC) members were cast and reinforced with CFRP sheets. The FRP flexural and shear strengthening RC beams has weakness in the spalling failure because the impact load concentrated the concrete face which is not strengthened with FRP sheets.

This paper presents the flexural behavior of a hybrid Glass Fiber-Reinforced Polymer(GFRP)-steel decks for use in deteriorated bridge decks replacement. Static load tests were conducted to investigate the structural characteristics of the hybrid FRP-steel deck. The tested deck panel satisfied the design criteria. The failure mode of the hybrid deck was demonstrated ductility with deformation beyond initial yielding. The responses were compared with the ANSYS finite element predictions. It was found that the presented hybrid deck was efficient for use in bridges. The thickness of the hybrid deck may be decreased when compared to that of the all FRP deck with similar flexural rigidity.

Cosmetic industry is a typical industry for domestic demand and is closely connected with domestic demand growth. In 2006, domestic cosmetics market is showing high growth rate due to the recovery of domestic demand and the market reorganization of sales channels is proceeding rapidly due to the recent global economic slowdown, Due to the situation, many companies are launching low-priced brand shop. The purpose of this study was to clarify the impact of marketing strategy of cosmetic brand-shop on consumers' purchasing intention. As the result of analyses, it was found that product, place, promotion factors of cosmetic brand-shop affect brand image. Also only product factor affects corporate image, perceived quality. And using regression analysis between brand image, corporate image, perceived quality and customer behaviors. Brand image and perceived quality factors influence consumers purchasing intention. Brand image has a positive impact on corporate image. And corporate image affects the perceived quality.