• Title/Summary/Keyword: Frame Stress

Search Result 652, Processing Time 0.027 seconds

Alterations in hematological parameters in Republic of Korea Air Force pilots during altitude chamber flight (저압실 비행 훈련이 대한민국 공군 조종사의 혈액 성분에 미치는 영향)

  • Kim, Hyun-Soo;Jeon, Eun-Ryoung
    • Journal of the Korean Society for Aviation and Aeronautics
    • /
    • v.20 no.2
    • /
    • pp.58-63
    • /
    • 2012
  • An altitude chamber, also known as a hypobaric chamber, is a device used during aerospace or high terrestrial altitude research or training to simulate the effects of high altitude on the human body. Although data from altitude chamber researches using experimental animals have been accumulated, studies in the humans exposed to hypobaric conditions are seldomly reported. Despite the importance of altitude chamber flight training in the field of aviation physiology, the hematological analysis of post-flight physiological changes has rarely been performed. The aims of the present study were to investigate the alterations in blood components during altitude chamber flight and to determine whether the differences between pre- and post-flight values are significant. Sixty experienced pilots in the Republic of Korea Air Force were enrolled in the altitude chamber flight training. Venous blood samples were obtained before and immediately after the flight. Compared with the pre-flight values($6.32{\times}10^3/mm^3$, $5.02{\times}10^6/mm^3$, 15.61 g/dL, respectively), white blood cell count, red blood cell count and hemoglobin level were significantly increased after the flight($6.77{\times}10^3/mm^3$, $5.44{\times}10^6/mm^3$, 16.26 g/dL; p=0.006, p=0.012, p<0.001, respectively). These alterations may be attributable to the exposure to hypobaric hypoxia, 100% oxygen supply for denitrogenation, considerable rise and fall in altitude and psychophysical stress due to these factors. In further studies, experimental groups and methods should be individualized to ensure objectivity and diversification. In addition, multiple time-frame analyses regarding the changing pattern of each blood component are also required to elucidate the physiological process for adapting to the high terrestrial altitude exposure.

A Study on the Symbolic Recognition Structure System of Space Design of a Hotel (호텔 공간디자인의 상징적 인식구조체계에 관한 연구)

  • Kim, Jeong-Ah;Kim, Uk
    • Korean Institute of Interior Design Journal
    • /
    • v.17 no.4
    • /
    • pp.92-101
    • /
    • 2008
  • A new paradigm of design lays stress on the world of metaphysical concepts, and various attempts are being made to give meaning to psychological values. Hotel is a memorable place to remind of a special moment in one's life such as travel, marriage, meeting and so on. It also contains even more symbolism than other spaces as it is the place where the most primary and private act takes place apart from one's residence. As a result, it is also possible to communicate the message which a designer intends to convey through the user's recognition in the form of various symbolic expressions in space design. The designer communicates a meaning into a space through a symbolic system and creates a mutual consensus by means of the understanding structure of "designer-space-user". The user's diverse interpretations through a symbol are based on epistemology and consist of the primary, the secondary and the tertiary recognition structure system in the aspect of their contents. The primary structure depends on sensual perception, impressive idea and transcendental recognition based on metaphysical and perceptional association. The secondary structure includes casualty, continuous deduction and rational(integral) recognition. Finally, the tertiary structure is sublimation to the transcendental mental world beyond the boundary of emotion and it is classified into fundamental recognition structure on an object and archetypical recognition structure on an ego. These characteristics can derive systematic understandings and diverse interpretations on the symbol from the space of a hotel through the frame of analysis based on the artistic form of monosemous, polysemous and multidimensional frameworks and symbols. The framework of this analysis includes all the cases, and various methods which haven't been attempted in practice are presented. Therefore this study is not just a simple analysis of space but rather it will serve as a methodological tool for design that allows for various attempts of symbolic design concepts in the recognition structure system.

A Numerical Study on the Apartment Structure Using Crossed Wide Girder (교차형 와이드 거더를 이용한 아파트구조의 수치해석적 연구)

  • Park, Jung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.8 no.5
    • /
    • pp.1186-1191
    • /
    • 2007
  • The study uses the crossed wide girder(waffle slab type) in apartment structural system comparing with existing shear wall system. The crossed wide girder will be able to secure the span of the longest which is possible with minimum slab thickness by not increasing the height. The research sees continuity arranges the crossed wide girder in schedule interval following the stress distribution. Namely, it is to make the interior space with the space without column and wall in the minimum height. In order to check the numerical value of this study which it interpreted the ductile frame system due to the crossed wide girder and existing shear wall system used the Midas Gen is a program which 3-dimension laterial force designs are possible. Analysis results, the crossed wide girder system is not disadvantageously laterial drift, drift ratio and deflection of slab compares with existing shear wall system. Also the whole concrete amount is similar existing shear wall system. The crossed wide girder is advantage which secure a architectal variability.

  • PDF

A Study on Stability Estimation of a Orchard Vehicle using Multi-Body Dynamic and Finite Element Analysis (다물체 동역학 및 유한요소 해석을 통한 과수원용 작업차량 안정성 평가에 관한 연구)

  • Han, Chang-Woo;Son, Jae-Hwan;Park, Kee-Jin;Jang, Eun-Sil;Woo, Seung-Min
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.14 no.9
    • /
    • pp.4142-4148
    • /
    • 2013
  • Because of effective fruit growing and management in the slope land, the use of orchard vehicle with lifting utilities has been increased. For this reason the study on the stability of that vehicle for worker's safety is needed. This study is investigated on the stability estimation of orchard vehicle with four wheels and dual rectangular-type lifting utilities which can be moved on the dirt sloping load. Through the multi-body dynamics analysis on the vehicle mechanism, overturning angles of 19.2 and $34.6^{\circ}$ in the right-left and front-rear direction can be calculated. It is determined tractive resistances and required powers of the wheels. And through the finite element analysis on the frame of lifting utility its maximum von-Mises stress is 146 MPa and it is structural stable. Therefore it is known that the orchard vehicle with wheels and lifting utilities has static and dynamic stability.

A Study on the Computational Design and Analysis of a Die Bonder for LED Chip Fabrication (LED칩 제조용 다이 본더의 전산 설계 및 해석에 대한 연구)

  • Cho, Yong-Kyu;Lee, Jung-Won;Ha, Seok-Jae;Cho, Myeong-Woo;Choi, Won-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.13 no.8
    • /
    • pp.3301-3306
    • /
    • 2012
  • In LED chip packaging, die bonding is a very important process which fixes the LED chip on the lead frame to provide enough strength for the next process. Conventional pick-up device of the die bonder is simply operated by up and down motion of a collet and an ejector pin. However, this method may cause undesired problems such as position misalignment and/or severe die damage when the pick-up device reaches the die. In this study, to minimize the position alignment error and die damage, a die bonder is developed by adopting a new pick-up head for precise alignment and high speed feeding. To evaluate structural stability of the designed system, required finite element model of the die bonder is generated, and structural analysis is performed. Vibration analysis of the pick-up head is also performed using developed finite element model at operation frequency range. As a result of the analysis, deformation, stress, and natural frequency of the die bonder are investigated.

Development of Structural Design Program to apply the Twin-Hull Car-ferry (쌍동형 카페리 구조설계용 프로그램 개발)

  • Lee, Jung-Ho;Oh, Jung-Mo;Seo, Kwang-Cheol
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.23 no.6
    • /
    • pp.731-738
    • /
    • 2017
  • Twin-hulls frequently incur structural damage at connecting members between the hull and deck induced by pitching motions during voyages. so, reasonable reinforcement is necessary around vulnerable spots such as corner knuckle, the chine bottom and inner hull. Since guidelines for structural design are not clear, engineers often respond by reinforcing plate thickness, changing stiffener sizes and reducing frame spacing, etc. These members constitute about 85 % of the longitudinal dimensions of the ship, so it is necessary to locally reinforce certain points to minimize weight stress, and also solve construction cost problems while securing the freeboard margin. Therefore, we developed a new program by analyzing the structural design procedures for the twin car-ferries based on Korean Register of Shipping (KR) High Speed Craft Rules, identifying items that need to be added. In order to ensure the reliability of buckling estimations for procedures and design programs, we conducted a comparative study with other standards and confirmed that differences were minimal.

Isolation and Characterization of Cyclophilin 1 (ClCyP1) Gene from Codonopsis lanceolata (더덕의 주근에서 유래한 Cyclophilin 1 (ClCyP1) 유전자의 분리 및 분석)

  • 양덕춘;이강;인준교;이범수;김종학
    • Korean Journal of Plant Resources
    • /
    • v.17 no.3
    • /
    • pp.239-247
    • /
    • 2004
  • A cyclophilin 1 cDNA clone(GenBank accession no.CF924191) was isolated from the taproot of C. lanceolata and designed as C1CyP1. Determination of the nucleotide sequence of C1CyPl identified an open reading frame of 525bp, which shared high homologies with cyclophilins that were previously reported in other organisms. The C1CyP1 amino acid sequence possesses 7 amino acid residue stretch(KSGKPLH) that is characteristic of plant cytosolic dehydrins. Currently available amino acid residues of plant cyclophilins were compared to examine their phylogenetic relationship to C1CyP1. In the phylogenetic analysis, based on the aligned sequences, C1CyP1 showed high homology with arabidopsis ROC2 and rice CyP1. The transcript that corresponded to C1CyP1 was abundant in callus, but only basal level of transcript was detected in stem, leaf and root. For the study in the defense mechanism against various stresses, we report expression patterns of this gene by quantative RT-PCR.

Isolation and Expression of Aluminum Induced Protein(ClAIP) Gene from Codonopsis lanceolata (더덕에서 Aluminum Induced Protein (ClAIP) 유전자의 분리 및 발현분석)

  • 양덕춘;김종학;인준교;이범수;이강
    • Korean Journal of Plant Resources
    • /
    • v.17 no.3
    • /
    • pp.289-296
    • /
    • 2004
  • A cDNA clone (GenBank accession no. CF924621) homologous to aluminum induced protein gene was isolated and characterized from Codonopsis lanceolata (ClAIP). The ClAIP is 906 nucleotides long and has an open reading frame of 711 bp with a deduced amino acid sequence of 236 residues. The ClAIP shows high homology to A. marina (84%), G. hirsutum(83%), V. radiata (83%), A. thaliana (80%), B. nap us (78%) and T. aestivum (68%). The deduced amino acid sequence of ClAIP also has homology to the N-terminal end of plant Asn synthetase. This region does not contain the active sites of the enzyme and the significance of this conservation is currently not clear. To investigate the expression of ClAIP against several heavy metal stresses, we treated the sliced tap root of C. lanceolata with various heavy metals. The expression of ClAIP was increased by 25 uM $Al_2$(SO$_3$)$_4$ in proportion to incubation time and also increased by 50 uM CdCl$_2$.

A Descriptive Study on the Function of Emotion in the Context of Eyewitness Testimony (목격자 증언 맥락에서 정서의 기능에 관한 서술적 고찰)

  • Lee, Seungjin
    • Journal of the Korea Convergence Society
    • /
    • v.13 no.5
    • /
    • pp.267-278
    • /
    • 2022
  • This paper was intended to examine the function of emotion that affects the accuracy of statements in the context of eyewitness testimony. The main emotion theories and concepts introduced in previous studies examining the relation between testimony accuracy and negative emotions were examined based on the characteristics of the research method. The results were presented in the order of emotion definition, emotion inducing method, and emotion measurement method. Specifically, the definition of emotion was described based on studies on negative emotions, arousal, stress, and mood. The emotion inducing method was mainly described based on images, virtual reality, and staged events designed by researchers, which have been mainly used in laboratories. Emotion measurement methods were described with respect to the self-report, behavioral checklist, and psychophysiology. In addition, the emotional approach for objective and scientific repeated verification, the importance of effective experimental design and appropriate scientific memory test, and the need for individual difference control were discussed. This paper reinterprets the contradictions shown by previous research by systematically structuring the function of emotion that affects the accuracy of testimony. It was meaningful to provide a frame for comparative analysis of related studies. Ultimately, it is expected that such knowledge will be used as basic documents for judging the reliability of eyewitness testimony in a legal context.

Vibration Analysis of Film Winding Core Automatic Supply System Using US Military Standards (미 군사규격을 적용한 권취 코어 자동공급장치의 진동해석)

  • Go, Jeong-Il;Park, Soo-Hyun;Hur, Jang-Wook
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.21 no.4
    • /
    • pp.91-99
    • /
    • 2022
  • By applying METHOD 514.8 of the US military standard MIL-STD-810H, vibration analysis of the winding core automatic feeding device was performed during vehicle transportation. The contact point between the LM guide and main support frame was weak in the vertical axis, transverse axis, and longitudinal axis during the transportation of the automatic winding core feeder vehicle, and the maximum equivalent stress was 236.31 MPa in the longitudinal axis. When random vibration was applied, the safety margin in the longitudinal direction was 0.26, indicating low safety. The safety margin was changed by increasing the damage factor to 0.1. Finally, the safety margin was improved to 3.48 to secure safety. Resonance occurred with a Q factor of 9.34 in the harmonic response to which the RMS value of the ASD data was input, and the vertical axis safety margin was derived as 0.16. When the damping factor was 0.15, the Q factor was 3.37, and resonance was avoided with a safety margin of 6.62.