• Title/Summary/Keyword: sidewall

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Optimal Design of Tire Sidewall Contour using Neural Network (신경회로망을 활용한 타이어 측벽형상의 최적설계)

  • Jeong, H.S.;Shin, S.W.;Cho, J.R.;Kim, N.J.;Kim, K.W.
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.378-383
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    • 2001
  • In order to improve automobile maneuverability and tire durability, it is very important for one to determine a suitable sidewall contour producing the ideal tension and strain-energy distributions. In order to determine such a sidewall contour, one must apply multi-objective optimization technique. The optimization problem of tire carcass contour involves several objective functions. Hence, we execute the tire contour optimization for improving the maneuverability and the tire durability using satisficing trade-off method. And, the tire optimization also requires long cup time for the sensitivity analysis. In order to resolve this numerical difficulty, we apply neural network algorithm.

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A Study on the Fluorine Effect of Direct Contact Process in High-Doped Boron Phosphorus Silicate Glass (BPSG)

  • Kim, Hyung-Joon;Choi, Pyungho;Kim, Kwangsoo;Choi, Byoungdeog
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.13 no.6
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    • pp.662-667
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    • 2013
  • The effect of fluorine ions, which can be reacted with boron in high-doped BPSG, is investigated on the contact sidewall wiggling profile in semiconductor process. In the semiconductor device, there are many contacts on $p^+/n^+$ source and drain region. However these types of wiggling profile is only observed at the $n^+$ contact region. As a result, we find that the type of plug implantation dopant can affect the sidewall wiggling profile of contact. By optimizing the proper fluorine gas flow rate, both the straight sidewall profile and the desired electrical characteristics can be obtained. In this paper, we propose a fundamental approach to improve the contact sidewall wiggling profile phenomena, which mostly appear in high-doped BPSG on next-generation DRAM products.

MOSFET Characteristics and Hot-Carrier Reliability with Sidewall Spacer and Post Gate Oxidation (Sidewall Spacer와 Post Gate Oxidation에 따른 MOSFET 특성 및 Hot Carrier 신뢰성 연구)

  • 이상희;장성근;이선길;김선순;최준기;김용해;한대희;김형덕
    • Proceedings of the IEEK Conference
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    • 1999.06a
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    • pp.243-246
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    • 1999
  • We studied the MOSFET characteristics and the hot-carrier reliability with the sidewall spacer composition and the post gate oxidation thickness in 0.20${\mu}{\textrm}{m}$ gate length transistor. The MOSFET with NO(Nitride+Oxide) sidewall spacer exhibits the large degradation of hot-carrier lifetime because there is no buffering oxide against nitride stress. When the post gate oxidation is skipped, the hot-carrier lifetime is improved, but GIDL (Gate Induced Drain Leakage) current is also increased.

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Thermal oxidation effect for sidewall roughness minimization of hot embossing master for polymer optical waveguides (고분자 광도파로용 핫엠보싱 마스터의 표면거칠기 최소화를 위한 열산화 영향)

  • 최춘기;정명영
    • Journal of the Korean Vacuum Society
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    • v.13 no.1
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    • pp.34-38
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    • 2004
  • Hot embossing master is indispensable for the fabrication of polymeric optical waveguides using hot embossing technology. Sidewall roughness of silicon master is directly related to optical loss of optical waveguides In this paper, a silicon master was fabricated by using a deep-RIE process. Additionally, thermal oxidation followed by oxide removal was carried out to minimize etched Si sidewall roughness. Thermal oxidation and oxide removal were performed with $H_2O_2$ atmosphere at $1050^{\circ}C$ and $NH_4$F:HF=6:l BOE, respectively, for the oxide thickness of 400$\AA$, 1000$\AA$, 3000$\AA$, 4500$\AA$, 5600$\AA$ and 6200$\AA$. The sidewall roughness was characterized by SEM and SPM-AFH measurements. We found that the roughness was improved from 12nm (RMS) to 6nm (RMS) for the scalloped sidewall and from 162nm (RMS) to 39nm (RMS) for the vertical striation sidewall, respectively.

High $f_T$ 30nm Triple-Gate $In_{0.7}GaAs$ HEMTs with Damage-Free $SiO_2/SiN_x$ Sidewall Process and BCB Planarization

  • Kim, Dae-Hyun;Yeon, Seong-Jin;Song, Saegn-Sub;Lee, Jae-Hak;Seo, Kwang-Seok
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.4 no.2
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    • pp.117-123
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    • 2004
  • A 30 nm $In_{0.7}GaAs$ High Electron Mobility Transistor (HEMT) with triple-gate has been successfully fabricated using the $SiO_2/SiN_x$ sidewall process and BCB planarization. The sidewall gate process was used to obtain finer lines, and the width of the initial line could be lessened to half by this process. To fill the Schottky metal effectively to a narrow gate line after applying the developed sidewall process, the sputtered tungsten (W) metal was utilized instead of conventional e-beam evaporated metal. To reduce the parasitic capacitance through dielectric layers and the gate metal resistance ($R_g$), the etchedback BCB with a low dielectric constant was used as the supporting layer of a wide gate head, which also offered extremely low Rg of 1.7 Ohm for a total gate width ($W_g$) of 2x100m. The fabricated 30nm $In_{0.7}GaAs$ HEMTs showed $V_{th}$of -0.4V, $G_{m,max}$ of 1.7S/mm, and $f_T$ of 421GHz. These results indicate that InGaAs nano-HEMT with excellent device performance could be successfully fabricated through a reproducible and damage-free sidewall process without the aid of state-of-the-art lithography equipment. We also believe that the developed process will be directly applicable to the fabrication of deep sub-50nm InGaAs HEMTs if the initial line length can be reduced to below 50nm order.

Changes in Fire Characteristics according to the Distance Between the Fire Source and Sidewall in a Reduced-Scale Compartment (축소 구획실에서 화원과 측벽의 거리에 따른 화재특성 변화)

  • Yun, Hong-Seok;Hwang, Cheol-Hong
    • Fire Science and Engineering
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    • v.33 no.1
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    • pp.50-59
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    • 2019
  • Experimental and numerical studies on the fire characteristics according to the distance between the fire source and sidewall under the over-ventilated fire conditions. A 1/3 reduced ISO 9705 room was constructed and spruce wood cribs were used as fuel. Fire Dynamics Simulator (FDS) was used for fire simulations to understand the phenomenon inside the compartment. As a result, the mass loss rate and heat release rate were increased due to the thermal feedback effect of the wall in the compartment fire compared to the open fire. As the distance between the fire source and sidewall was reduced, the major fire characteristics, such as maximum mass loss rate, heat release rate, fire growth rate, temperature, and heat flux, were increased despite the limitations of air entrainment into the flame. In particular, a significant change in these physical quantities was observed for the case of a fire source against the sidewall. In addition, the vertical distribution of temperature was changed considerably due to a change in the flow structure inside the compartment according to the distance between the fire source and sidewall.

In-depth exploration of machine learning algorithms for predicting sidewall displacement in underground caverns

  • Hanan Samadi;Abed Alanazi;Sabih Hashim Muhodir;Shtwai Alsubai;Abdullah Alqahtani;Mehrez Marzougui
    • Geomechanics and Engineering
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    • v.37 no.4
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    • pp.307-321
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    • 2024
  • This paper delves into the critical assessment of predicting sidewall displacement in underground caverns through the application of nine distinct machine learning techniques. The accurate prediction of sidewall displacement is essential for ensuring the structural safety and stability of underground caverns, which are prone to various geological challenges. The dataset utilized in this study comprises a total of 310 data points, each containing 13 relevant parameters extracted from 10 underground cavern projects located in Iran and other regions. To facilitate a comprehensive evaluation, the dataset is evenly divided into training and testing subset. The study employs a diverse array of machine learning models, including recurrent neural network, back-propagation neural network, K-nearest neighbors, normalized and ordinary radial basis function, support vector machine, weight estimation, feed-forward stepwise regression, and fuzzy inference system. These models are leveraged to develop predictive models that can accurately forecast sidewall displacement in underground caverns. The training phase involves utilizing 80% of the dataset (248 data points) to train the models, while the remaining 20% (62 data points) are used for testing and validation purposes. The findings of the study highlight the back-propagation neural network (BPNN) model as the most effective in providing accurate predictions. The BPNN model demonstrates a remarkably high correlation coefficient (R2 = 0.99) and a low error rate (RMSE = 4.27E-05), indicating its superior performance in predicting sidewall displacement in underground caverns. This research contributes valuable insights into the application of machine learning techniques for enhancing the safety and stability of underground structures.

A Study on the Fatigue Characteristics and Life Prediction of the Tire Sidewall Rubber (타이어 사이드월 고무의 피로특성 및 수명예측에 관한 연구)

  • Moon, Byungwoo;Kim, Yongseok;Jun, Namgyu;Koo, Jae-Mean;Seok, Chang-Sung;Hong, Ui Seok;Oh, Min Kyeong;Kim, Seong Rae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.7
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    • pp.629-634
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    • 2017
  • In the case of the UHP (Ultra high performance) tire that the demand has increased rapidly, compared with the commonly used tire, severe deformation has been observed because of the low aspect ratio. When repeated deformations are applied to the sidewall rubber, accumulated fatigue damage may cause fatigue failure. Thus, the evaluation of the durability of the tire sidewall rubber has become a very important issue to prevent accidents that occur while the vehicle is running. However, the research and design criteria for the durability performance of the tire sidewall rubber hardly exist. In this study, we suggest a lifetime prediction formula using strain energy density obtained by performing tensile tests and fatigue tests on two different kinds of the tire sidewall compounds. Additionally, the applicability of our findings for low fuel consumption tires was reviewed by converting the fatigue life of the sidewall rubber into the expected mileage of the tire.

An Experimental Study on Ship-Bank Hydrodynamic Interaction Forces (선박에 작용하는 측벽영향에 관한 실험적 연구)

  • Lee, Chun-Ki
    • Journal of Navigation and Port Research
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    • v.37 no.3
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    • pp.251-256
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    • 2013
  • This paper is mainly concerned with the ship-bank interaction by model test. The experiments for the characteristics of hydrodynamic interaction forces and moments between vessel and bank with a mound were carried out in the seakeeping and maneuvering basin. A series of tests were carried out with ship model in parallel course along a vertical sidewall with a mound with varying lateral spacing between model ship and sidewall, length of sidewall and water depth. From the experimental results, it indicated that the hydrodynamic interaction effects increase as length of sidewall with a mound increases. Furthermore, for lateral spacing less than about 0.2L between vessel and bank, it can be concluded that the bank effects increase largely as the lateral spacing between vessel and bank decreases. However, for spacing between vessel and bank more than about 0.3L, the interaction effects increase slowly as lateral spacing decreases. Also, for the water depth to draft ratio(h/d) less than about 1.5, the hydrodynamic interaction effects increase dramatically as h/d decreases.