• Title/Summary/Keyword: H-section

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Phase Separation Characteristics of Low Temperature Bunsen Reactions In Sulfur-Iodine Hydrogen Production Process (황-요오드 수소 제조 공정에서 저온 분젠 반응의 상 분리 특성)

  • Han, Sang-Jin;Lee, Kwang-Jin;Kim, Hyo-Sub;Kim, Young-Ho;Park, Chu-Sik;Bae, Ki-Kwang;Lee, Jong-Gyu
    • Transactions of the Korean hydrogen and new energy society
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    • v.22 no.4
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    • pp.424-431
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    • 2011
  • The Sulfur-Iodine(SI) thermochemical hydrogen production process consists of three sections, which are so called the Bunsen reaction section, the $H_2SO_4$ decomposition section and the HI decomposition section. In order to identify the phase separation characteristics in the reaction conditions with the high solubility of $SO_2$, we conducted the Bunsen reaction at the low temperatures, ranging from 283 to 298K, with the $I_2/H_2O$ molar ratios of 2.5/16.0 and 3.5/16.0. The molar ratios of HI/$H_2SO_4$ products obtained from low temperature Bunsen reactions were ca. 2, indicating that there were no side reactions. The amount of reacted $SO_2$ was increased with decreasing the temperature, while the amounts of unreacted $I_2$ and $H_2O$ were decreased. In the phase separation of the products, the amount of a $H_2SO_4$ impurity in $HI_x$ phase was increased with decreasing the temperature, though the temperature has little affected on HI and $I_2$ impurities in $H_2SO_4$ phase.

Evaluation of Structural Stability at High Temperature for H-section Beams Made of Ordinary Strength Steels by Analytic Method (일반 구조용 강재 적용 H형강 보부재의 해석에 의한 고온내력 평가 연구)

  • Kwon, In-Kyu
    • Fire Science and Engineering
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    • v.28 no.2
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    • pp.76-81
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    • 2014
  • Structural stability of structural beams at high temperature had been evaluated though a horizontal furnace and a standard fire curve. If a structural method and a material are satisfied with the fire test, those are seemed to be guaranteed the safety of residences, fire services men, and properties of the buildings. However, that requires not only longer period but higher cost for making and testing of each structural element. That restrained from developing new methods and new fire protective materials. In this study, an analytic method was executed to demonstrate whether the analytic method using mechanical properties of structural steel at high temperature with heat transfer theory works is working. In this paper, the surface temperature rising and variance of structural stability of a simple H-section beam with a standard fire curve were evaluated and structural stabilities of H-section beam according to differences from length of beam were suggested.

Study on suitable substrate formulation for bottle and bag cultivation of Pleurotus pulmonarius (산느타리(Pleurotus pulmonarius) 병·봉지재배에 적합한 배지조성 연구)

  • Lee, Jae-Hong;Lee, Nam-Gil;Park, Young-Hak;Mun, Youn-Gi;Jeong, Tae-Sung;Kwon, Sun-Bae;Kim, Jae-Rok;Kim, Jin-Won
    • Journal of Mushroom
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    • v.12 no.4
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    • pp.275-279
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    • 2014
  • Pleurotus pulmonarius usually grows on the dead wood of deciduous trees from mid summer to early fall. Cultivation of this mushroom is recently increasing due to its good flavour and fragrance. This study was conducted to find out the favorable substrate formulation in the bottle and bag cultivation of P. pulmonarius. The V formulation (10 : 50 : 20 : 20 mixing ratio of poplar sawdust, cottonseed hull, cottonseed meal and beet pulp) showed the fastest mycelial growth in the test tube column medium and highest yields in both bottle cultivation and bag cultivation. Those chemical conditions were pH 5.52, 29.07% organic matter contents, 1.12% total nitrogen, 25.95 OM/N ratio, 0.16% CaO, 0.51% $K_2O$, 0.17 MgO and 0.26 $P_2O_5$.

Fundamental Studies on the Net-Shape of the Drag Net-II On the Section Shape of the Simplified Model of the Bag Net in Four-Point Suspension (저예망의 어구형상에 관한 기초적 연구-II 단순화모형에 의한 4폭짜리 자루그물의 단면형상)

  • Lee, Ju-Hee
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.20 no.2
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    • pp.65-71
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    • 1984
  • As a primary step in studying the relationship between the arrangement of netting and the section shape of the bag net in the four-seam trawling net, a series of experiments were performed with the simplified model of the bag net made of vinyl film. This model was suspended horizontally in circularly flowing water, with two pairs of suspending threads to four points of symetry at the border of the bag mouth in place of both wing nets. And then, the area distribution of each panel in the bag net was arranged by the portion of the length of the side panel, q to that of the lower or upper panel, p at the border of bag mouth. In the experiments, the section shape of the bag mouth photographed and the tensions on both pairs of suspending threads were measured with two loadcells in circularly flowing water. From the results that the section shape of the bag mouth in circularly flowing water is controlled by the area distribution of panels in the bag net, the author estimated an experimental equation. h/w=k sub(1) e super(k) 2 super(q/p)+C, where h is the central height of the bag mouth, and w is the lateral width of that.

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Study on the Difference of Pulse Waveform Parameter with Applied Variations of Pressure (측정가압에 의한 좌관부위(左關部位) 맥파요인 변화에 대한 실험 연구)

  • Kim, Gyeong-Cheol;Lee, Jeong-Won;Ryu, Kyeong-Ho;Kang, Hee-Jung;Yim, Yun-Kyoung
    • Korean Journal of Acupuncture
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    • v.27 no.4
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    • pp.59-72
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    • 2010
  • Objectives : In the study on the waveform analysis of radial artery pulse diagnosis, we need to establish fundaments of contemporary pulse diagnosis research, and to find the change of pulse waveform parameter with applied variation pf pressure. Methods : As we will to do experimental research on the difference of pulse waveform on the radial artery with applied variations of pressure(5 stage-pressure) and measuring position(left KWAN). In this research, we analyzed the change of the waveform according to five stage pressure. Results : The results were as follows; When we analyzed the change of the waveform according to pressure in the left KWAN, E, hl, h2 and A were the difference between 8ths pressure grades in 95% trust section. And t2, t4 were the difference between 8ths pressure grades in 95% trust section. W was the difference between 8ths pressure grades in 95% trust section. And h2/h1 was the difference between 6ths pressure grades in 95% trust section. There is the difference between 1st and 2nd grade & between 2nd and 5th grade in the case of t4/t2 in 95% trust section. And there is the difference between 1st and 5th grade, between 3rd and 4th grade, between 3rd and 5th grade & between 4th and 5th grade in the case of W/A in 95% trust section. And there is the difference between 1st and 2nd grade, between 2nd and 3rd grade, between 2nd and 4th grade, between 3rd and 4th grade, between 3rd and 5th grade & between 4th and 5th grade in the case of A/E in 95% trust section. Conclusions : We found the statistically resonable differences between each pulse depending on the applied pressure. And Analysing the radial pulse(left KWAN) at 5 applied pressure levels may be useful to study on the pulse waveform diagnosis.

Design and Fabrication of Miniaturized Chipless RFID Tag Using Modified Bent H-shaped Slot (변형된 구부러진 H-모양 슬롯을 이용한 소형 Chipless RFID 태그 설계 및 제작)

  • Junho Yeo;Jong-Ig Lee
    • Journal of Advanced Navigation Technology
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    • v.27 no.6
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    • pp.815-820
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    • 2023
  • In this paper, the design method of a miniaturized chipless RFID tag using a modified bent H-shaped slot was proposed. The proposed modified bent H-shaped slot was appended on the rectangular conductor plate printed on one side of a 20 mm × 50 mm FR4 substrate with a thickness of 0.8 mm. The resonant dip frequency of the bistatic RCS for the proposed modified bent H-shaped slot was compared with the cases when the H-shaped, U-shaped slot, and bent H-shaped slots were added, respectively, on the conductor plate. The simulated resonant dip frequencies for H-shaped, U-shaped, and bent H-shaped slots were 5.907 GHz, 4.918 GHz, and 4.364 GHz, respectively. When the proposed modified bent H-shaped slot was added, the resonant dip frequency was decreased to 3.741 GHz, and, therefore, the slot length was reduced by 36.7% compared to the H-shaped slot case. Experiment results show that the resonant dip frequency of the fabricated modified bent H-shaped slot was 3.9 GHz.

A Study On Lateral Buckling Of H-Section Steel Beams (H형(形) 강(鋼) 보의 횡좌굴(橫挫屈)에 관(關)한 연구(硏究))

  • Kim, Seok-Jung
    • Journal of Industrial Technology
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    • v.4
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    • pp.29-35
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    • 1984
  • Buckling is a significant behavior to be considered whenever we design steel structures. In the case of H-shape beams, the lateral buckling occured by bending moment must be considered. Because of the lateral buckling of H-shape beams, the bending strength of the beams are determined by the lateral buckling stress instead of the allowable bending stress. Lateral buckling stress equation, consisting of two terms, i. e. ${\sigma}_{cr}({\nu},{\omega})={\sqrt{[{\sigma}_{cr}({\nu})]^2+[{\sigma}_{cr}({\omega})]^2}}$ has been using, but for the practical purpose of use the following equations are using two, i. e. ${\sigma}_{cr}({\nu})={\frac{0.65E}{{\ell}_h/A_f}}$, ${\sigma}_{cr}({\omega})={\frac{{\pi}^2E}{({\ell}_b/i_b)^2}}$. When we use the above equations, the results are different according to the shape of beam section, and they a re rather complex. In this study lateral buckling stress equation is derived, and the proposed formula$({\sigma}_{cr}(t))$ is compared with above mentioned two basic and practical equations. To verify the proposed formula experimentaly, 16H-shape beams which have different slender ratios arc tested by applying pure bending momet. Through the experiments the buckling behavior of H-shape beams is clarified, and the results shows that the proposed formula$({\sigma}_{cr}(t))$ is accurate enough for practical purpose.

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An Experimental Study on the Local Buckling of Welded H-Shape Steel Beam (용접(熔接)H형강(型鋼) 보의 국부좌굴(局部挫屈)에 관한 실험적(實驗的) 연구(硏究))

  • Kim, Seok-Jung
    • Journal of Industrial Technology
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    • v.1
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    • pp.9-16
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    • 1981
  • In the steel Structural design, buckling is the main factor to determine size, particularly in compression member. Buckling may sometimes occur in the form of wrinkles in thin elements, such as webs, flanges, and other parts that make up a section. This phenomenon is called local buckling. The strength of the steel and the rigidity of the frame are considerably deteriorated by the local buckling. The specimens used for this experiments, H-Shape Steel beams composed by fillet-welding, are dessified classified into two groups, ie one for web test and another for flange fest. The aim of this study is to define the influences by the local bucking on the vesisting forces, deformation and the phenomena of the internal forces in the section, and to collect the basic data for design of steel beams.

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Control System Design of Electric Operated Adjustable Bed for Body Posture Stability (체간 안정성을 위한 전동침대의 제어시스템 설계)

  • Bae, J.H.;Moon, I.
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.6 no.2
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    • pp.55-62
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    • 2012
  • In this paper we propose a control system to preserve the interior angle between back section and upper leg section to be larger than 90 degrees using a single limit switch. To design the control system we analyze the kinematics of actuation mechanisms for the back section and the upper leg section, and find out an optimal solution for the controller design. Using a prototype control system we perform experiments to test the controller performance, and show that the interior angle between the back section and the upper leg section is always preserved larger than 90 degree. From the experimental results, we show the proposed control system is feasible to keep the body posture stability.

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