• Title/Summary/Keyword: Stacking

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Study of Dynamic Characteristics of Stacking and Transfer System for the Solid freeform fabrication System (임의형상가공시스템의 적층 및 이송장치 동특성연구)

  • 엄태준;주영철;민상현;김승우;공용해;천인국;방재철
    • Proceedings of the KAIS Fall Conference
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    • 2002.11a
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    • pp.246-248
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    • 2002
  • This paper presents computer simulations of the stacking and transfer system for the fast freeform fabrication system. The stacking and transfer system is essential for the fast freeform fabrication system and its stable motion is very important fer the consistent stacking of the cut slices. The stacking and transfer system cane be modeled as a pneumatic system. The system consists of air compressor, the control valve, and the cylinder. The governing parameters have been changed and the simulation results are shown to predict the time response of the system. The results shows some parameters should be correctly tuned to obtain stable system response.

The Effect of Air Vent Holes and Stacking Methods of Fruits and Vegetables Boxes on Static Pressure Drop in Pressure Cooling System (청과물상자의 통기공 및 상자적재방법이 정압강하에 미치는 영향)

  • 김의웅;김병삼;남궁배;정진웅;김동철;금동혁
    • Journal of Biosystems Engineering
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    • v.20 no.4
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    • pp.360-367
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    • 1995
  • The effect of air vent holes, stacking methods of boxes and clearance between boxes on static pressure drop, were measured to design of pressure cooling system. Static pressure drops in air vent hole of carton box were measured for different hole opening ratio from 1% to 5%. Static pressure drop was expressed as a function of superficial velocity as second-degree polynomial. At given static pressure in plenum chamber, static pressure drop in boxes was shown as second-degree polynomial of the number of carton box in series stacking method, as first-degree polynomial in height and parallel stacking method. In pressure cooling of 24 boxes of Tsugaru apple, air flow rates through clearance between the boxes were shown 1.27 and 1.65 times than those of through the inside of boxes at the plenum pressure of 10mmAq and 20mmAq, respectively.

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Processing and Characterization of a Direct Bonded SOI using SiO$_2$ Thin Film (SiO$_2$ 박막을 이용한 SOI 직접접합공정 및 특성)

  • 신동운;최두진;김긍호
    • Journal of the Korean Ceramic Society
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    • v.35 no.6
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    • pp.535-542
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    • 1998
  • SOI(silicon oninsulator) was fabricated through the direct bonding of a hydrophilized single crystal Si wafer and a thermally oxidized SiO2 thin film to investigate the stacking faults in silicon at the Si/SiO2 in-terface. At first the oxidation kinetics of SiO2 thin film and the stacking fault distribution at the oxidation interface were investigated. The stacking faults could be divided into two groups by their size and the small-er ones were incorporated into the larger ones as the oxidation time and temperature increased. The den-sity of the smaller ones based critically lower eventually. The SOI wafers directly bonded at the room temperature were annealed at 120$0^{\circ}C$ for 1 hour. The stacking faults at the bonding and oxidation interface were examined and there were anomalies in the distributions of the stacking faults of the bonded region to arrange in ordered ring-like fashion.

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Load and Capacitor Stacking Topologies for DC-DC Step Down Conversion

  • Mace, Jules;Noh, Gwangyol;Jeon, Yongjin;Ha, Jung-Ik
    • Journal of Power Electronics
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    • v.19 no.6
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    • pp.1449-1457
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    • 2019
  • This paper presents two voltage domain stacking topologies for powering integrated digital loads such as multiprocessors or 3D integrated circuits. Pairs of loads and capacitors are connected in series to form a stack of voltage domains. The voltage is balanced by switching the position of the capacitors in one case and the position of the loads in the other case. This method makes the voltage regulation robust to large differential load power consumption. The first configuration can be named the load stacking topology. The second configuration can be named the capacitor stacking topology. This paper aims at proposing and comparing these two topologies. Models of both topologies and a switching scheme are presented. The behavior, control scheme, losses and overall performance are analyzed and compared theoretically in simulation and experiments. Experimental results show that the capacitor stacking topology has better performance with a 30% voltage ripple reduction.

Effect of stacking sequence on thermal stresses in laminated plates with a quasi-square cutout using the complex variable method

  • Chaleshtari, Mohammad H. Bayati;Khoramishad, Hadi
    • Structural Engineering and Mechanics
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    • v.77 no.2
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    • pp.245-259
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    • 2021
  • In this research, the influence of the laminate stacking sequence on thermal stress distribution in symmetric composite plates with a quasi-square cutout subjected to uniform heat flux is examined analytically using the complex variable technique. The analytical solution is obtained based on the thermo-elastic theory and the Lekhnitskii's method. Furthermore, by employing a suitable mapping function, the solution of symmetric laminates containing a circular cutout is extended to the quasi-square cutout. The effect of important parameters including the stacking sequence of laminates, the angular position, the bluntness, the aspect ratio of cutout, the flux angle and the composite material are examined on the thermal stress distribution. It is found out that the circular shape for cutout may not necessarily be the optimum geometry for all stacking sequences. The finite element analysis results are used to validate the analytical solution.

Predicting movie audience with stacked generalization by combining machine learning algorithms

  • Park, Junghoon;Lim, Changwon
    • Communications for Statistical Applications and Methods
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    • v.28 no.3
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    • pp.217-232
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    • 2021
  • The Korea film industry has matured and the number of movie-watching per capita has reached the highest level in the world. Since then, movie industry growth rate is decreasing and even the total sales of movies per year slightly decreased in 2018. The number of moviegoers is the first factor of sales in movie industry and also an important factor influencing additional sales. Thus it is important to predict the number of movie audiences. In this study, we predict the cumulative number of audiences of films using stacking, an ensemble method. Stacking is a kind of ensemble method that combines all the algorithms used in the prediction. We use box office data from Korea Film Council and web comment data from Daum Movie (www.movie.daum.net). This paper describes the process of collecting and preprocessing of explanatory variables and explains regression models used in stacking. Final stacking model outperforms in the prediction of test set in terms of RMSE.

Dynamic Weight Adjustment Algorithms for Deriving Stacking Policies of Automated Container Terminals (자동화 컨테이너터미널의 장치 위치 결정을 위한 동적 가중치 조정 알고리즘)

  • Kim, Young-Hun;Park, Tae-Jin;Ryu, Kwang-Ryel
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2007.12a
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    • pp.255-256
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    • 2007
  • In case of inappropriate stacking position of the container taking in container yard, the working time for the container would be delayed in taking out because of the occurrence of the re-handle and the increase of the crane moving time. We have to take into account a variety of elements like the crane interference, the container group and stacking height in order to determine the optimal stacking position and decide the weight reflecting the importance of these criteria. We propose the dynamic weight adjustment algorithm for the stacking policy criteria employing the online search in this research.

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A Study of Dynamic Characteristics of Stacking and Transferring System for the Solid Freeform Fabrication System (임의형상가공시스템의 적층 및 이송장치 동특성연구)

  • 엄태준;주영철;민상현;김승우;공용해;천인국;방재철
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.3 no.4
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    • pp.280-284
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    • 2002
  • This paper presents computer simulations of the stacking and transferring system for the fast freeform fabrication system. The stacking and transferring system is essential for the fast freeform fabrication system and its stable motion is very important for consistent stacking of the cut slices. The stacking and transferring system can be modeled as a pneumatic system. The system consists of air compressor, the control valve, and the cylinder. The governing parameters have been changed and the simulation results are shown to predict the time response of the system. The results show some parameters should be correctly tuned to obtain stable system response.

  • PDF