This paper is concerned with the mechanical design of hyperbaric oxygen chamber for multi-users using stress analysis. HBOT(Hyperbaric Oxygen Therapy) is very effective medical equipment for increasing the concentration of melted oxygen in human and animal body. The hyperbaric oxygen supplies to the impaired cell of human and animal to recover the healthy condition. This research reported the design specifications and mechanical safety of hyperbaric oxygen chamber using computational stress analysis with CATIA program. The result from this research can be used for making the practical HBOT equipment for multi-users and to manufacture the real model

Adhensively bonded joints in dissimilar materials have been widely applied in various engineering fields such as automobiles, space vehicle, semiconductor, vessel. To establish a fracture criterion and a reasonable strength evaluation method on adhensively interfaces in dissimilar materials, it is necessary to assess fracture parameters with various bonding conditions. In this paper, through stress analysis by using the 2-dimensional elastic boundary element method(BEM), the stress singularity factors on adhensively bonded joint in dissimilar materials were investigated quantitatively, and suggested the strength evaluation method by using fracture parameters

본 논문은 고온 스트레스가 우유 생산량에 미치는 영향을 분석했다. 분석을 위해 모형 2개를 구축했다. 모형 1은 우유생산량과 THI를 비선형관계로 가정하여 우유생산량이 가장 많아지는 최적의 THI를 추정했다. 이를 위해 고온 스트레스를 정량화 시킨 THI를 산출했다. 모형 2는 우유생산량과 평균기온과 습도의 관계를 분석했다. 습도는 우유생산량과의 통계적 상관관계가 존재하지 않아 배제하였다. 우유생산량과 평균기온은 비선형관계로 가정하여 최적의 기온, 기온 변화에 따른 우유생산량의 한계효과와 농가소득의 변화분까지 추정하였다. 분석 결과, 최적의 THI는 자기상관을 고려하지 않은 경우 17.79 고려한 경우 7.91로 나타났다. 최적의 평균기온은 자기상관을 고려하지 않은 경우 16.5℃. 고려한 경우 7.4℃로 나타났다. 기온에 의한 우유생산량의 한계효과는 최적 기온을 기점으로 양의 한계효과는 감소하다 최적 기온을 넘어서면 음의 한계효과로 바뀌며 온도가 상승할수록 음의 한계효과는 커지는 것으로 분석되었다. 농가소득 변화분은 농가의 착유우두수가 많고 기온 변화가 클수록 더욱 커지는 것으로 나타났다.

Firefighters receive extreme stress and suffer from PTSD in disaster. But we have not been paid attention to them. The purpose of this study is to analyze the problems of previous PTSD education programs in fire academy and to present the practical educational programs for firefighters to use in the disaster field. In the empirical analysis of this practical educational programs(EFT program), this program is more effective than existing theory-focused education training program.

Reactive oxygen and nitrogen species (ROS and RNS, respectively) are messengers that carry signals to alter the redox state in order to activate plant responses and other physiological processes, such as differentiation, aging, senescence, and pathogen defense. Quite a large number of genes are involved in this signaling and lead to oxidative stress in plants. Although the role of ROS/RNS during stress conditions is well documented, a comprehensive list of genes and comparative study of these genes has not yet been completed. Accordingly, the in silico identification of oxidative stress-related genes was performed for soybeans and Arabidopsis. These genes were also studied in relation to multiple domain prediction. The presence of domains like dehydogenase and ATPase suggests that these genes are involved in various metabolic processes, as well as the transportation of ions under optimal environmental conditions. In addition to a sequence analysis, a phylogenetic analysis was also performed to identify orthologous pairs among the soybean and Arabidopsis oxidative stress-related genes based on neighbor joining. This study was also conducted with the objective of further understanding the complex molecular signaling mechanism in plants under various stress conditions.

Friction welding in dissimilar materials is widely applied in various engineering fields such as automobiles, rolling stocks, machine tools. Since interface edges of Friction-welded materials have stress singularity by differences of mechanical properties and temperature changes, it is necessary to assess stress singularity with the variation of flash shape and length. In this paper, the influences which the flashes created by friction welding concern to the stress singularity at interface edges are investigated. Through stress analysis by the BEM and static experiments, the influences were studied quantitatively, the stress singularity greatly depends on the shape of the flash and its size.

Thermo-mechanical fatigue cracks on the turbine housing of turbochargers are often observed in currently developed gasoline engines for them to adopt lightness and higher performance levels. Maximum gas temperatures of gasoline engines usually exceed 950℃ under engine test conditions. In order to predict thermo-mechanical failures by simulation method, it is essential to consider temperature-dependent inelastic materials and inhomogeneous temperature distributions undergoing thermal cyclic loads. This paper presented the analytical methods to calculate thermal stresses and plastic strain ranges for the prediction of fatigue failures on the basis of motoring test mode, which is commonly used for accelerated engine endurance test. The analysis results showed that the localized critical regions with large plastic strains coincided well with crack locations from a thermal shock test.

The purpose of this study was to examine the dietary habits of boarding high school students in Gangwon based on gender and stress levels. Questionnaires were distributed to 571 boarding high school students and collected from 491 students from June 28 to July 20, 2011. The statistical data analyses were completed using SPSS (ver. 19.0) for the descriptive analysis, independent sample t-test and 2-test. The mean stress score was 23.7 out of 40, and male's stress was significantly higher than female's (p〈0.05). The rates of having daily breakfast and dinner were significantly influenced by gender (p〈0.01), and the regularity of lunch was significantly different depending on the stress level (p〈0.05). Female students consumed less flour based foods (p〈0.01), carbonated drinks (p〈0.01), juices (p〈0.05) and functional drinks (p〈0.01) than male students, but male students consumed less cookies and breads (p〈0.01). Dietary habits that boarding high school students should improve were an unbalanced diet (38%), too much intake at once (17%) and prejudice against foods (11%), and their primary value in dietary life was preference (33%), followed by staving off hunger (18%) and pleasure (18%). The average level of interest in dietary life was 2.46 (on a Likert-type 3-point scale) and it was significantly higher for female students (2.53) than male (2.40) (p〈0.05). About 54% of students washed their hands before a meal when they thought of it, but only 25% of students always scrubbed up. The regularity of breakfast and dinner, frequency of snack intake, dietary habits that need to improve, intrest in dietary life, and washing hands before meals showed significant difference by gender but not by stress levels.

This study analyzes lifes and damages at automotive tie rod through the structural analyses with fatigue. The structural result of this study can be effectively utilized with the design of automotive tie rod by investigating prevention and durability against its damage.

In this paper, an efficient yet accurate method for the thermal stress analysis using a first order shear deformation theory(FSDT) is presented. The main objective herein is to systematically modify transverse shear strain energy through the mixed variational theorem(MVT). In the mixed formulation, independent transverse shear stresses are taken from the efficient higher-order zigzag plate theory, and the in-plane displacements are assumed to be those of the FSDT. Moreover, a smooth parabolic distribution through the thickness is assumed in the transverse normal displacement field in order to consider a transverse normal deformation. The resulting strain energy expression is referred to as an enhanced first order shear deformation theory, which is obtained via the mixed variational theorem with transverse normal deformation effect(EFSDTM_TN). The EFSDTM_TN has the same computational advantage as the FSDT_TN(FSDT with transverse normal deformation effect) does, which allows us to improve the through-the-thickness distributions of displacements and stresses via the recovery procedure. The thermal stresses obtained by the present theory are compared with those of the FSDT_TN and three-dimensional elasticity.

고주파 처리는 파밤나방(Spodoptera exigua)의 생리변화를 유발시켜 섭식행동, 발육 및 면역반응의 변화를 초래한다. 본 연구는 이러한 고주파의 영향을 파밤나방의 생화학적 변화를 통해 분석했다. 고주파(5,000 Hz, 95 dB) 처리는 중장 상피세포의 단백질 합성과 분비를 억제시켰다. 또한 이 고주파 처리는 중장의 인지질분해(phospholipase ) 소화효소의 활성을 현격하게 억제시켰다. 고주파 처리는 세 종류의 열충격단백질과 지질운송단백질(apolipophorin III)의 유전자 발현을 변동시켰고 이러한 변화는 중장 조직에서 뚜렷했다. 혈림프 혈장에 존재하는 지질 및 유리당의 함량이 고주파 처리에 의해 현격하게 증가했다. 이러한 결과는 고주파 처리가 파밤나방의 체내 생화학적 변화를 유발시켜 생리적 교란을 유도하는 스트레스로 작용한다는 것을 제시하고 있다.

With increasing use of SUH35/SUH3 dissimilar materials for automotive engine valves, it is required that stress singularities under residual stress on an interface for friction welded dissimilar materials analyzed to establish strength evaluation. The stress singularity index() and stress singularity factor( ) were calculated by using the results of stress analysis considering residual stress and loads. The stress singularities on variations for temperatures and loads acting from outside were analyzed and discussed. This paper suggested that the strength evaluation by using the stress singularity factors as fracture parameters, considering the stress singularity on an interface edge of friction welded dissimilar materials will be useful.

플라스틱 Pallet와 함께 많이 사용되고 있는 골판지는 다른 포장 재료에 비해 무게가 가벼워 물류비 절감 효과를 가져 온다. 수출품의 형태와 조건에 맞는 다양한 강도와 형태 제작이 가능해 성형성이 좋고, 외부 충격에 대한 손상을 방지 할 수 있다. 그러나 기존에 골판지의 물성치가 알려지지 않아 구조해석이 어려워 구조적인 설계가 어려웠다. 골판지를 이용한 구조물 설계는 경험과 노하우에만 의존하여 포장 용기를 제작하여 정밀한 계산을 할 수 없었다. 본 논문의 연구목적은 골판지를 소재로 한 구조물 설계에서 정확도를 높이고자 설계해석 프로그램을 이용하여 응력해석을 하는데 있다. 골판지 소재로 물품의 받침대로 이용되어 상품을 적재할 때 사용되는 Pallet을 설계하고 구조를 해석 프로그램을 통해 좀 더 안전하고 신뢰성 있게 제작할 수 있도록 골판지의 물성치 값을 적용하여 응력해석을 수행한다.

A kart is a vehicle without the suspension system and the differential gear. The kart frame as an elastic body plays the role of a spring. By the cornering of a kart, rolling, pitching and twisting motions are induced in the kart frame. Also the slip or noncontact of the wheel and a permanent deformation of the kart frame can be induced. In order to examine closely this phenomenon of the twisting deformation, measurement and analysis on torsion working stress with strain gage and tracking system are needed. According to the measurement result, while steady state driving in a curve in general the torsion working stress of the kart frame will be increased depending on the vehicle velocity, but the kart frame will be not permanent deformed. However, analysis of the torsion working stress in comparison with torsion fatigue limit shows that while unsteady state driving as clash with same drive condition the racing kart frame will be deformed more quickly as the leisure kart frame.

The safety at this study is investigated by flow or stress analyses due to configuration or installation direction of fuel tank in the existing CNG bus. In case of the lower ceiling with sharp type, the equivalent stress due to the explosion of fuel tank is less than the type of flat or arc. it becomes safer on passenger. In case of the installation direction of fuel tank in the existing CNG bus, the stress applied on the lower ceiling at transverse direction becomes less than at longitudinal direction. It is more stable on the safety of passenger. The harm on the explosion accident can be prevented by use of the analysis result at this study.

선박에 사용되는 TEMA 열교환기 전열관의 확관 공정에서 발생되는 탄소성 응력과 변형량의 거동을 유한요소법으로 해석하였다. 열교환기의 관판 구명의 홈 깊이와 롤러 익스팬더의 작용압력을 변화시켜 해석한 결과, 전열관의 관판 구멍의 홈 깊이가 커지면 탄소성 압축응력은 감소하였고, 롤러 익스팬더 압력이 높을수록 관판 구멍의 홈 모서리 부분의 탄소성 응력이 증가되었다.

This study investigated the adverse effects of sound treatment on physiological processes of the American leafminer, Liriomyza trifolii, during several developmental stages. Larval feeding activity was analyzed by measuring feeding tunnel length. It was significantly suppressed by sound treatment (5,000 Hz, 95 dB). Sound treatment delayed the pupal period at 315 - 5,000 Hz and prevented adult emergence at 1,000 - 5,000 Hz. Female oviposition was also inhibited by the stress sound treatments. However, phototactic adult movement was not affected by sound treatment. Pupae treated with 5,000 Hz showed marked changes in protein pattems analyzed by two dimensional electrophoresis. MALDI-TOF analysis of specific protein spots indicated that trafficking protein particle complex I, triosephosphate isomerase, hypothetical protein TcasGA2_TC013388, polycystin-2, paraneoplastic neuronal antigen MAl, and tropomyosin I (isoform M) were predicted in the control insects and disappeared in the insects treated with sound. By contrast, DOCK9, cytoskeletal keratin II, and F0F1-ATP synthase beta subunit were predicted only in the sound-treated insects. Furthermore, stress sound significantly increased the susceptibility of L. trifolii to insecticides. These results suggest that physiological processes of L. trifolii are altered by sound stress, which may be exploited to develop a novel physical control tactic against L. trifolii.

프로테오믹스 기법을 이용하여 벼 고온 스트레스 관련 단백질을 분리 동정하기 위하여 에서 고온처리한 벼의 줄기로부터 단백질을 분리하였다. 분리한 단백질로부터 Rubisco 단백질을 제거하기 위해 15% PEG fractionation을 실시한 후 상등액 분획의 단백질을 이차원전기 영동한 후, CBB 염색을 통해 차별적 발현을 보이는 단백질을 분석하였다. 총 46개의 단백질 spot이 발현양에 변화를 보였으며, 그 중 24개의 단백질이 고온 스트레스에 의해

A system approach for studying the engine dynamic characteristics requires a cranktrain flexible body dynamic model including crankshaft, connecting rod and piston. By using a multi-body dynamics code, LMS Virtual Lab, rigid body dynamic model and flexible multi-body dynamic model were established. From these models, the dynamic loads acting on the crankshaft were calculated. Rigid model for V12 engine cranktrain with components connected by kinematical constraints was transformed into a flexible model by replacing rigid crankshaft and connecting rods with flexible ones. And to secure the credibility of flexible body model, three kinds of flexible models were tried, i.e. a model with a fully flexible crankshaft, model with a partially flexible crankshaft(1/6 of the whole length), and a partial detailed flexible model(with finer meshes). The results from each model were compared, and a partial detailed model with finer meshes was found to give reasonable stress values within relatively short period of computing time.