• 제목/요약/키워드: Science box

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강재 플레이트 유한요소해석을 이용한 잔교 상부의 풀 박스 부재의 선정 (Design of Pull Box Members on the Landing Pier Using Finite Element Analysis of a Steel Plate)

  • 김성원;홍혜민;한택희;서승남
    • 한국연안방재학회지
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    • 제4권3호
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    • pp.111-118
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    • 2017
  • In this study, pull box members were designed by finite element analysis of a steel plate covering a pull box to secure its safety on the landing pier dedicated to the large research survey ship. It was assumed that the maximum load is due to the 250 tonf class crane used for unloading work when the working environment in the upper part of the landing pier was considered. The safety of the pull box was evaluated by the comparison between the yield strength of the steel plate and the result of stress analysis on the steel plate due to the crane load. It was found that the stress at the plate from the crane load exceeded the yield strength of the steel(205MPa) when the upper part of the pull box was protected by a $1950{\times}1950mm$ steel plate cover. In order to compensate for this, a concrete filled steel tube(CFT) column with a diameter of 150 mm and a steel thickness of 10 mm was reinforced at the center of the plate, and the finite element analysis was carried out. However, the maximum stress at the steel plate was higher than the yield strength of the steel in some load cases so that it was tried to find appropriate thickness of the steel plate and diameter of the CFT columns. Finally, the analysis results showed that the safety of the pull box was secured when the thickness of the steel plate and the diameter of the CFT column were increased to 30mm and 180mm, respectively.

($Zn(BOX)_{2}$$Zn(BTZ)_{2}$의 광발광 특성 및 전계발광 특성에 대한 전기 화학적 연구 (An Electrochemical Study on Photoluminescent and Electroluminescent Characteristics of $Zn(BOX)_{2}$ and $Zn(BTZ)_{2}$)

  • 박지영;권오관;최돈수;김영관;손병청;하윤경
    • 한국응용과학기술학회지
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    • 제17권1호
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    • pp.63-66
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    • 2000
  • Organic Electroluminescent devices(OELD) consisted of multilayer structures have been studied for the application the application to flat-panel display. Metal-chelate complexes, zinc bis(2-(2-hydroxyphenyl)benzoxazolate) ($Zn(BOX)_{2}$) and zinc bis(2-(2-hydroxyphenyl)benzothiazolate) ($Zn(BOX)_{2}$), have been intensively investigated as an white-light emitting layer and recognized to have good electroluminescent(EL) properties. In this study, ($Zn(BOX)_{2}$) and ($Zn(BTZ)_{2}$) were synthesized and characterized by FT-IR, $^{1}H-NMR$, UV-VIS and PL. Their EL properties were also studied and their ionization potential(IP) and electron affinity(EA) were also measured by cyclic voltammetry(CV).

Indirect displacement monitoring of high-speed railway box girders consider bending and torsion coupling effects

  • Wang, Xin;Li, Zhonglong;Zhuo, Yi;Di, Hao;Wei, Jianfeng;Li, Yuchen;Li, Shunlong
    • Smart Structures and Systems
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    • 제28권6호
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    • pp.827-838
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    • 2021
  • The dynamic displacement is considered to be an important indicator of structural safety, and becomes an indispensable part of Structural Health Monitoring (SHM) system for high-speed railway bridges. This paper proposes an indirect strain based dynamic displacement reconstruction methodology for high-speed railway box girders. For the typical box girders under eccentric train load, the plane section assumption and elementary beam theory is no longer applicable due to the bend-torsion coupling effects. The monitored strain was decoupled into bend and torsion induced strain, pre-trained multi-output support vector regression (M-SVR) model was employed for such decoupling process considering the sensor layout cost and reconstruction accuracy. The decoupled strained based displacement could be reconstructed respectively using box girder plate element analysis and mode superposition principle. For the transformation modal matrix has a significant impact on the reconstructed displacement accuracy, the modal order would be optimized using particle swarm algorithm (PSO), aiming to minimize the ill conditioned degree of transformation modal matrix and the displacement reconstruction error. Numerical simulation and dynamic load testing results show that the reconstructed displacement was in good agreement with the simulated or measured results, which verifies the validity and accuracy of the algorithm proposed in this paper.

데카르트의 심신론이 의학에 미친 영향 (The impact of Rene Descartes′s Mind-Body Theory on Medicin)

  • 반덕진
    • 보건행정학회지
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    • 제10권1호
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    • pp.31-56
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    • 2000
  • A purpose of this study is to study on Rene Descartes's mind-body theory in medical aspect. Though Rene Descartes was not so much a doctor as a philosopher, he had health and medical science at heart. When he came into the world in 1596, he was in poor health. Therefore, he suffered from his bad health. Descartes's ideas absolutely colored Western thought for three hundred years, especially, his mind-body theory, mechanistic life-view, and reductionism had important effect on medical study and science of public health. As a rule, we know that his mind-body theory was applicable to mind-body dualism, and his mind-body dualism was connected with biomedical model of medicine. But by this study, his mind-body theory was not only mind-body dualism but also mind-body monoism. And he asserted mind-body interaction too. In other words, he advocated mind-body dualism in scientific aspect, but he knew mind-body monoism from his experence. He confessed this fact to Princess Elizabeth of Bohemia, he wrote mind-body interaction in $\boxDr$Discours de la methode$\boxUl$, $\boxDr$Meditationes de prima philosophia$\boxUl$, and $\boxDr$Traite des passions de 1'ame$\boxUl$ etc. However, only mind-body dualism of his mind-body theories was written in our medical text book, morever mental realm was excluded from the persuit of learning Descartes advocated a mechanistic world-view and mechanistic life-view, he regarded human body as a machine part. And a paticent corresponds to a troubled machine, a doctor deserves a repairman. But this point of view made holistic understanding of man impossible. Descartes divide the whole into basic building blocks, we named the approach Reductionism. Reductionism led to ontological concept in medical science, bacteriology established 'specific cause-specific disease-specific therapy'. We examined medical influence of Descartes's thought, we need to draw out a philosophic basis of medical science and science of public health by a close study of his records.

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Genome-wide survey and expression analysis of F-box genes in wheat

  • Kim, Dae Yeon;Hong, Min Jeong;Seo, Yong Weon
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.141-141
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    • 2017
  • The ubiquitin-proteasome pathway is the major regulatory mechanism in a number of cellular processes for selective degradation of proteins and involves three steps: (1) ATP dependent activation of ubiquitin by E1 enzyme, (2) transfer of activated ubiquitin to E2 and (3) transfer of ubiquitin to the protein to be degraded by E3 complex. F-box proteins are subunit of SCF complex and involved in specificity for a target substrate to be degraded. F-box proteins regulate many important biological processes such as embryogenesis, floral development, plant growth and development, biotic and abiotic stress, hormonal responses and senescence. However, little is known about the F-box genes in wheat. The draft genome sequence of wheat (IWGSC Reference Sequence v1.0 assembly) used to analysis a genome-wide survey of the F-box gene family in wheat. The Hidden Markov Model (HMM) profiles of F-box (PF00646), F-box-like (PF12937), F-box-like 2 (PF13013), FBA (PF04300), FBA_1 (PF07734), FBA_2 (PF07735), FBA_3 (PF08268) and FBD (PF08387) domains were downloaded from Pfam database were searched against IWGSC Reference Sequence v1.0 assembly. RNA-seq paired-end libraries from different stages of wheat, such as stages of seedling, tillering, booting, day after flowering (DAF) 1, DAF 10, DAF 20, and DAF 30 were conducted and sequenced by Illumina HiSeq2000 for expression analysis of F-box protein genes. Basic analysis including Hisat, HTseq, DEseq, gene ontology analysis and KEGG mapping were conducted for differentially expressed gene analysis and their annotation mappings of DEGs from various stages. About 950 F-box domain proteins identified by Pfam were mapped to wheat reference genome sequence by blastX (e-value < 0.05). Among them, more than 140 putative F-box protein genes were selected by fold changes cut-offs of > 2, significance p-value < 0.01, and FDR<0.01. Expression profiling of selected F-box protein genes were shown by heatmap analysis, and average linkage and squared Euclidean distance of putative 144 F-box protein genes by expression patterns were calculated for clustering analysis. This work may provide valuable and basic information for further investigation of protein degradation mechanism by ubiquitin proteasome system using F-box proteins during wheat development stages.

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재생페트를 이용한 고단열 패키징 개발과 기존의 스티로폼 및 종이 박스와의 단열성능 비교 (Development of High-insulation Packaging using Recycled PET and Comparison of Insulation Performance with Existing Styrofoam and Paper Boxes)

  • 류재룡;육세원;갈승훈;신양재
    • 한국포장학회지
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    • 제25권3호
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    • pp.111-116
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    • 2019
  • Thermal insulation performance of new insulation packaging made of recycled PET nonwoven (thickness : 10 mm) was verified by conducting comparative experiment with an EPS box (thickness : 25 mm) and a double wall corrugated box (thickness : 7 mm). Three ice packs (300 g) were positioned 200 mm above the bottom inside each box, all of which are placed side by side and temperature change of 2 points (5mm under middle icepack and 130 mm under middle icepack) was recorded by data logger (GL-840, Graphtec) for 16 hours under the environment of 29℃. The new packaging box showed 75% higher insulation performance than the EPS box and 180% higher than the corrugated box. In order to figure out the reason for insulation performance difference among boxes, thermal conductivities of each box material were measured using heat flow meter (HFM436 lamda, Netzsch). U-value (thermal conductivity divided by thickness) of EPS was lower than recycled pet nonwoven by 57%, which seemed to be opposite to the result of insulation test of boxes. This was explained by high water vapor transmission rate of EPS (6 times higher than PET insulation) and air pocket effect of PET insulation.

Cut-out이 있는 Box형 차체의 하부구조 소재대체 경량화 설계 방법 (A Weight-reduction Design Method by Underframe Material Substitution in a Box-type Bodyshell with Cut-outs)

  • 조정길;구정서;정현승
    • 한국자동차공학회논문집
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    • 제21권2호
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    • pp.45-54
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    • 2013
  • In this paper, a theoretical weight-reduction method was suggested to substitute an underframe material of a box-type bodyshell having cut-outs with an alternative light-weight material. To utilize the material substitution method previously developed for a box-type hybrid bodyshell not having cut-outs, we derived a box-type baseline model without cut-outs which is similar to the stiffness condition of a box-type bodyshell having cut-outs. To do this, the thicknesses of roof and walls of the baseline model were determined such that the deflection of the baseline model under a distributed vertical load condition is equal to the sum of the theoretical section deflections of the original box model with cut-outs. Next, to derive a hybrid bodyshell by under-frame material substitution, the material substitution method for a box-type hybrid bodyshell without cut-outs was applied to the box-type baseline model. Finally, we compared the FE simulation results of the derived hybrid bodyshells having cut-outs for various materials with the theoretical results of the suggested method, and we obtained their good correlations.

농산물 포장용 골판지상자의 수송 중 진동에 의한 압축강도 변화 (Effect of Vibration during Distribution Process on Compression Strength of Corrugated Fiberboard Boxes for Agricultural Products Packaging)

  • 신준섭;김종경
    • 한국포장학회지
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    • 제27권2호
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    • pp.91-100
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    • 2021
  • Agricultural corrugated fiberboard packaging boxes frequently experience damage due to loading and unloading, vibration during transport, and shock by dynamic distribution condition change. This study was carried out to estimate effect of vibration during distribution process on compression strength of corrugated fiberboard boxes for agricultural products. In order to identify the degradation caused by vibration, after box packaging the agricultural products(tangerine or cucumber), the natural frequencies of the packaging boxes were measured by varying the relative humidity(50, 70 and 90%) at 25℃ temperature. Various types of corrugated fiberboard boxes were packed with tangerines and cucumbers, and the PSD plot vibration tests were conducted by utilizing the actual vibration recording results of the Gyeongbu Expressway section between Seoul and Gimcheon. As a result of the experiment, the decrease in compression strength of the box was relatively low in DW-AB, and the decrease in compression strength of the SW-A 0201(RSC) type box was the highest at 20.49%. In particular, both SW-A and DW-AB showed low compression strength degradation rates for open folder type boxes. The moisture content varies depending on the type of the box or agricultural products, and the enclosed 0201(RSC) type box was generally higher than the open folder or bliss type box, which is believed to be the reason for the decrease in compression strength of RSC type box due to humidity. By the agricultural product, the percentage of decrease in compression strength of box packed with cucumbers was especially high.