• Title/Summary/Keyword: D-shaped stage

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Structural Design and Construction for Tall Damped Building with Irregularly-Shaped Plan and Elevation

  • Yamashita, Yasuhiko;Kushima, Soichiro;Okuno, Yuuichirou;Morishita, Taisei
    • International Journal of High-Rise Buildings
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    • v.7 no.3
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    • pp.255-264
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    • 2018
  • This paper introduces three distinctive means for the use of a 189-meter high damped structure ensuring safety against earthquake: 1. Realization of L-shaped elevational structural planning: The bottom and top of the tower have belt trusses and hat trusses respectively to restrain the bending deformation. Furthermore, large-capacity oil dampers (damping force 6,000 kN) are installed in the middle part of the tower to restrain the higher-mode deformation. 2. Realization of L-shaped planar structural planning: We devised a means of matching the centers of gravity and rigidity by adjusting planar rigidity. Moreover, viscous damping devices are located at the edges of the L-shaped plan, where torsional deformation tends to be amplified. We call this the "Damping Tail" system. 3. Composite foundation to equalize deformations under different loading conditions: We studied the vertical and horizontal deformations using sway-rocking and 3D FEM models including the ground, and applied multi-stage diameter-enlarged piles to the tower and a mat foundation to the podium to keep the foundations from torsional deformations and ensure structural safety.

An Experimental Research on Performance and Emission Characteristics of Direct-Injection Diesel Engines with Annular Two-stage Combustion Chamber (환상 2단연소실을 갖는 직접분사식 디젤기관의 성능 및 배출물 특성에 관한 실험적 연구)

  • Kim, D.H.;Bae, J.U.
    • Journal of Power System Engineering
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    • v.7 no.4
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    • pp.12-18
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    • 2003
  • Various measures have been tried to reduce the NOx emission from diesel engine, but with partial success because the mechanisms of NOx and PM formations appear to have trade-off relation between each other. Therefore it has been known to be difficult to reduce NOx emission and PM emission simultaneously. Two stage combustion method i,e. a combustion process which has rich combustion stage and lean combustion stage one by one, has been developed successfully to reduce NOx formation in the continuous combustion chambers such as in the boilers. But until yet it is not successful to apply the same method in intermittent combustion chamber like in the diesel engine cylinder, as it was, only several research works were carried out. In this study, devised was a uniquely shaped combustion chamber with reformed piston crown intended to keep fuel-rich condition during early stage of combustion and fuel-lean condition during next stage. It was found that the NOx emission decreased significantly at various conditions of operation with the two stage combustion type engines of PR20 type, but other values such as smoke, CO and specific fuel consumption deteriorated as usual.

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Connection between Acoustical Parameters and Solo Performance on a Concert Hall Stage (콘서트홀 무대에서 음향지표와 독주 연주와의 상관관계)

  • Kim, Yong-Hee;Lee, Chang-Woo;Seo, Chun-Ki;Jeon, Jin-Yong
    • The Journal of the Acoustical Society of Korea
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    • v.27 no.6
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    • pp.296-302
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    • 2008
  • This study investigated that the preference model of soloist performers for both vocal and instrumental types in terms of a stage support parameter, ST1. The test was carried out on a stage of a fan-shaped multi-purpose hall with orchestra shell. Objective measurements were carried out at 15 positions on the stage to evaluate various stage condition. The results showed that ST1 varies between -19.9 and -11.3 dB. Vocal and instrumental players participated in performance evaluation test as they played at 5 selected positions according to ST1 values. Players' preference was evaluated by 5-point rating and rank ordering method. As a result, it was found that the preference model of vocalist is different from that of instrumentalist. It was also found that the ST1 does not correlate well with the performer's preference.

Effect of Temperature, Salinity and Density on the Egg Development of the Sunray Surf Clam, Mactra chinensis (개량조개, Mactra chinensis의 난발생에 미치는 수온, 염분 및 수용밀도의 영향)

  • Min, Byeong-Hee;Kim, Tae-Jin
    • The Korean Journal of Malacology
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    • v.26 no.4
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    • pp.297-302
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    • 2010
  • Water temperature, salinity and density on egg development of the sunray surf clam, Mactra chinensis were investigated for artificial seedling production. The required time from fertilization to D-shaped larvae were 33.8 hours in $18^{\circ}C$, 20.6 hours in $23^{\circ}C$, 18.2 hours in $28^{\circ}C$ and 15.0 hours in $33^{\circ}C$. The development duration was reduced with increasing temperature. The relationships between temperature and the required time from egg to each developmental stage were described as follows: 2-cell, 1/h = 0.1051WT - 1.4782; 8-cell, 1/h = 0.037WT - 0.3686; gastrula, 1/h = 0.008WT - 0.0521; trochophore, 1/h = 0.0041WT - 0.0235; D-shaped larva, 1/h = 0.0024WT - 0.0102. Biological minimum temperature for the egg development was estimated to be $8.0^{\circ}C$ in average. The possible range of temperature for the development of D-shaped larvae was $18-28^{\circ}C$ and optimum of water temperature for the development of egg was $23^{\circ}C$. The possible range of salinity for the development of D-shaped larvae was 20-35 psu and optimum of salinity for the development of egg was 30-35 psu over 25 psu at least. The density of fertilized egg was below 40 per 1 ml in rearing seawater for elevating the development rate from fertilized egg to D-shaped larva.

Studies on the Artificial Seedling Production of Geoduck Clam, Panope japonica II. Development of Egg and larvae (코끼리조개의 인공종묘생산에 관한 연구 II. 난발생과 유생의 발달)

  • Lee, Chae-Sung;Rho, Sum
    • Journal of Aquaculture
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    • v.10 no.1
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    • pp.25-32
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    • 1997
  • Develoment precess and characteristics of eggs of the geoduck clam, Panope japonica are reporting in this study. Eggs and sperm were excised from gonad, artificially fertilized in an aquarium, reared under various temperature regimes, and record and record the larval period and the time need to reach a certain larval stage from ferilization. Unfertilized eggs of P. japonica appeared to be oval with a mean diameter of $70\mu$m and they became spherical after fertilization. The eggs of P. japonica can be classified as demersal. At a constant water temperature of $ 11^{citc}C$, it took 4 hours form fertilization to become four-cell stage, two days to become trochophore larvae, three days to become D-shape larvae, twenty-three days to become umbo stage, and thirty-six days to become fully grown veliger ready form settlement. A negative correlation was observed between the water temperature and the larval period of P. japonica. From fertilization to D-shape larvae, it took five days at 8$^{\circ}C$, while it was only two days to become D-shape larvae at $ 17^{citc}C$. Time required to D-shape larvae from fertilization was proportional to temperature, and the relationships were expressed as follows : To 8-cell stage, 1/t=0.0209 w-0.1167 (r=0.9967) To blastula stage, 1/t=0, 0055 w-0.0192 (r=0.9825) To trochophore stage, 1/t=0.0034 w-0.0155 (r=0.9907) To D-shape larvae stage, 1/t=0.0014 w-0.0023 (r=0.9843) (t, time in hours ; w, water temperature) Bioligical minimum temperature for egg development was calculated as 3.82$^{\circ}C$ in average.

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Fabrication and characterization of the 0.25 ${\mu}m$ T-shaped gate P-HEMT and its application for MMIC low noise amplifier (0.25 ${\mu}m$ T형 게이트 P-HEMT 제작 및 특성 평가와 MMIC 저잡음 증폭기에 응용)

  • Kim, Byung-Gyu;Kim, Young-Jin;Jeong, Yoon-Ha
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.1
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    • pp.38-46
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    • 1999
  • o.25${\mu}m$ T-shaped gate P-HEMT is fabricated and used for design of X0band three stage monolithic microwave integrated circuit(MMIC) low noise amplifier(LNA). The fabricated P-HEMT exhibits an extrinsis transconductance of 400mS/mm and a drain current of 400mA/mm. The RF and noise characteristics show that the current gain cut off frequency is 65GHz and minimum noise figure(NFmin) of 0.7dB with an associated gain of 14.8dB at 9GHz. In the design of the three stage LNA, we have used the inductive series feedback circuit topology with the short stub. The effects of series feedback to the noise figure, the gain, and the stability have been investigated to find the optimal short stub length. The designed three staage LNA showed a gain of above 33dB, a noise figure of under 1.2dB, and ainput/output return loss of under 15dB and 14dB, respectively. The results show that the fabricated P-HEMT is very suitable for a X-band LNA with high gain.

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Development of Vehicle Members with Spot Welded Thin-wall Section for Optimum Impart Characteristic -Based on Collapse Characteristics on the Varied Impact Velocities- (최적 충격특성에 갖는 차체구조용 점용접 박육단면부재의 개발 -충격속도변화에 따른 압궤특성을 중심으로-)

  • Yang, In-Yeong;Cha, Cheon-Seok;Gang, Jong-Yeop
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.25 no.7
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    • pp.1131-1138
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    • 2001
  • This paper concerns the crashworthiness of the widely used vehicle structure, the spot welded hat and double hat shaped section members, which are excellent on the point of the energy absorbing capacity and low production cost. The target of this paper is to analyze the energy absorption capacity of the structure against the front-end collision, and to obtain useful information for designing stage. Changing the spot weld pitches on the flanges, the hat and double hat shaped section members were tested on the axial collapse loads in impact velocities of 4.72m/sec, 6.54m/sec, 7.19m/sec and 7.27m/sec. To efficiently review the collapse characteristics of these sections, the simulation have been carried out using explicit FEM package, LS-DYNA3D. The solutions are compared with results from the impact collapse experiments.

The Influence of Developmental Stages and Different Kinds and Concentrations of Protective Additives in Cryopreservation of Surf Clam (Spisula Sachalinensis) Larvae

  • Park, Youn-Hee;Jo, Pil-Gue;Chang, Young-Jin
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2002.11a
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    • pp.104-104
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    • 2002
  • This study was performed to find out the optimal larval stage among trochophore, D-shaped and umbo stage larvae and the desirable protective additive such as fructose, glucose, sucrose and trehalose with cryoprotectant for cryopreservation of surf clam, Spisula sachalinensis larvae. Dimethyl sulfoxide and ethylene glycol were used as cryoprotectant and each cryoprotectant was made to 2.0 M with previous protective additives. The larvae were immersed in the preparations waited for 15 minutes to reach equilibration, and then frozen in a program freezer (-35$^{\circ}C$) and liquid nitrogen (-196$^{\circ}C$). The freezing rate of 1.0$^{\circ}C$ /min. was used for cryopreservation of trochophores before seeding temperature (-12$^{\circ}C$). The survival rate of frozen-thawed larvae increased as larval developing and that of umbo stage larvae was the highest as 96.1 ${\pm}$ 1.0%. The presence of lower concentration of disaccharides as sucrose or trehalose significantly enhanced survival rate when mixed with cryoprotectants (P<0.05). The results of our study indicate that desirable developmental stages of larvae and protective additive for cryopreservation are the umbo stage larvae and 0.2 M sucrose, respectively.

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A High Gain V-band CPW Low Noise Amplifier

  • Kang, Tae-Sin;Sul, Woo-Suk;Park, Hyun-Chang;Park, Hyung-Moo;Rhee, Jin-Koo
    • Proceedings of the IEEK Conference
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    • 2002.07b
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    • pp.1137-1140
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    • 2002
  • A V-band low-noise amplifiers (LNA) based on the Millimeter-wave monolithic integrated circuit (MIMIC) technology were fabricated using high performance 0.1 $\mu\textrm{m}$ $\Gamma$-shaped pseudomorphic high electron mobility transistors (PHEMT's), coplanar waveguide (CPW) structures and the integrated process for passive and active devices. The low-noise designs resulted in a two-stage MIMIC LNA with a high S$\sub$21/ gain of 14.9 dB and a good matching at 60 ㎓. 20 dBm of IP3 and 3.9 dB of minimum noise figure were also obtained from the LNA. The 2-stage LNA was designed in a chip size of 2.3 ${\times}$1.4 mm$^2$by using 70 $\mu\textrm{m}$ ${\times}$2 PHEMT’s. These results demonstrate that a good low-noise performance and simultaneously with a high gain performance is achievable with GaAs PHEMT's in the 60 ㎓ band.

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A Prototype Implementation for 3D Animated Anaglyph Rendering of Multi-typed Urban Features using Standard OpenGL API

  • Lee, Ki-Won
    • Korean Journal of Remote Sensing
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    • v.23 no.5
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    • pp.401-408
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    • 2007
  • Animated anaglyph is the most cost-effective method for 3D stereo visualization of virtual or actual 3D geo-based data model. Unlike 3D anaglyph scene generation using paired epipolar images, the main data sets of this study is the multi-typed 3D feature model containing 3D shaped objects, DEM and satellite imagery. For this purpose, a prototype implementation for 3D animated anaglyph using OpenGL API is carried out, and virtual 3D feature modeling is performed to demonstrate the applicability of this anaglyph approach. Although 3D features are not real objects in this stage, these can be substituted with actual 3D feature model with full texture images along all facades. Currently, it is regarded as the special viewing effect within 3D GIS application domains, because just stereo 3D viewing is a part of lots of GIS functionalities or remote sensing image processing modules. Animated anaglyph process can be linked with real-time manipulation process of 3D feature model and its database attributes in real world problem. As well, this approach of feature-based 3D animated anaglyph scheme is a bridging technology to further image-based 3D animated anaglyph rendering system, portable mobile 3D stereo viewing system or auto-stereo viewing system without glasses for multi-viewers.