• Title/Summary/Keyword: System form

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Cultural Implications of Science and Technology (과학기술의 문화적 함의)

  • Lim Hy-Sop
    • Journal of Science and Technology Studies
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    • v.3 no.1 s.5
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    • pp.1-17
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    • 2003
  • Though science and technology can understood as a part of cultural system, the relationship of science/technology with culture is often viewed as contradictory or mutually exclusive by many scholars. Therefore, in the first section of the present paper, the nature of science and technology as a cultural form is examined. Here, science is viewed as a form of symbolic culture, while technology is regarded as a form of instrumental culture. In the second section, the contradictory relationship and/or tensions between science-technological system (instrumental culture) and cultural system (symbolic culture) within a society is discussed. In the final section of this paper, 'science culture' is conceptualized as a dynamic social process in which contradictory science sub-cultures of political system(state), economic system(cooperations), civil society (including academic community of scientists and other social organizations and movements), and cultural system are supposed to be coordinated. In conclusion, establishment of 'humanized science culture' and 'democratic science-culture movement' is proposed as an alternative way of resolving contradictory relationship between cultural system and science-technological system in the modern world.

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THREE DIMENSIONAL FINITE ELEMENT STRESS ANALYSIS OF FIVE DIFFERENT TAPER DESIGN IMPLANT SYSTEMS (3차원 유한요소법적 분석을 이용한 5종의첨형 임플랜트에 발생하는 응력의 비교연구)

  • Byun, Sang-Ki;Park, Won-Hee;Lee, Young-Soo
    • The Journal of Korean Academy of Prosthodontics
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    • v.44 no.5
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    • pp.584-593
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    • 2006
  • Statement of problem : Dental implant which has been developed gradually through many experiments and clinical applications is presently used to various dental prosthetic treatments. To conduct a successful function of implant prosthesis in oral cavity for a long time, it is important that not only structure materials must have the biocompatibility, but also the prosthesis must be designed for the stress, which is occurred in occlusion, to scatter adequately of load support. Therefore, it is essential to give the consideration about the stress analysis of supporting tissues for higher successful rates. Purpose : Recently, many implant manufacturing company produce various taper design of root form implant, the fixture is often selected. However, the stress analysis of taper form fixture still requires more studies. Material and method : This study we make the element models that five implant fixture; Branemark system(Nobel Biocare, Gothenberg, Sweden), Camlog system(Altatec, Germany), Astra system(Astra Tech, Sweden), 3i system(Implant Innovations Inc, USA), Avana system(Osstem, Korea) were placed in the area of mandibular first premolar and prosthesis fabricated, which we compared with stress distribution using the three-dimension finite element analysis under two loading condition. Results : This study compares the aspect of stress distribution of each system with the standard of Von mises stress, among many resulted from finite element analysis so that this research gets the following results. 1. In all implant system, oblique loading of maximum Von mises stress of implant, alveolar bone and crown is higher than vertical loading of those. 2. Regardless of loading conditions and type of system, cortical bone which contacts with implant fixture top area has high stress, and cancellous bone has a little stress. under the vertical loading, maximum Von mises stress is more higher in order of Branemark, Camlog, Astra, 3i, Avana. under the horizontal loading, maximum Von mises is more higher in order of Camlog, Branemark, Astra, 3i, Avana.

On-line Motion Synthesis Using Analytically Differentiable System Dynamics (분석적으로 미분 가능한 시스템 동역학을 이용한 온라인 동작 합성 기법)

  • Han, Daseong;Noh, Junyong;Shin, Joseph S.
    • Journal of the Korea Computer Graphics Society
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    • v.25 no.3
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    • pp.133-142
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    • 2019
  • In physics-based character animation, trajectory optimization has been widely adopted for automatic motion synthesis, through the prediction of an optimal sequence of future states of the character based on its system dynamics model. In general, the system dynamics model is neither in a closed form nor differentiable when it handles the contact dynamics between a character and the environment with rigid body collisions. Employing smoothed contact dynamics, researchers have suggested efficient trajectory optimization techniques based on numerical differentiation of the resulting system dynamics. However, the numerical derivative of the system dynamics model could be inaccurate unlike its analytical counterpart, which may affect the stability of trajectory optimization. In this paper, we propose a novel method to derive the closed-form derivative for the system dynamics by properly approximating the contact model. Based on the resulting derivatives of the system dynamics model, we also present a model predictive control (MPC)-based motion synthesis framework to robustly control the motion of a biped character according to on-line user input without any example motion data.

Development of Self-microemulsifying Drug Delivery System for Enhancing the Bioavailability of Atorvastatin

  • Jin, Shun-Ji;Cho, Won-Kyung;Park, Hee-Jun;Cha, Kwang-Ho;Park, Jun-Sung;Koo, Ja-Seong;Wang, Hun-Sik;Kim, Jeong-Soo;Kim, Min-Soo;Hwang, Sung-Joo
    • Journal of Pharmaceutical Investigation
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    • v.41 no.2
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    • pp.103-109
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    • 2011
  • The objective of the study was to prepare self-microeulsifying drug delivery system (SMEDDS) incorporating atorvastatin calcium and evaluate its properties and oral bioavailability. Solubility of atorvastatin in various vehicles was determined. Pseudo-ternary phase diagrams were constructed to identify the good self-emulsification region. The droplet size distributions of the resultant emulsions were determined by dynamic light scattering measurement. The mean droplet size of chosen formulation (20% ethyl oleate, 40% tween-80, 40% Carbitol$^{(R)}$) was $23.4{\pm}1.3$ nm. The SMEDDS incorporating atorvastatin calcium appeared to be associated with better performance in dissolution and pharmacokinetic studies, compared with raw atorvastatin calcium. In dissolution test, the release percentage of atorvastatin from SMEDDS mixture could rapidly reach more than 95% within 3 min. Oral $AUC_{0{\rightarrow}8hr}$ values in SD rats was $1994{\pm}335\;ng{\cdot}hr/mL$, which significantly increased (P<0.05) compared with raw atorvastatin calcium. The SMEDDS formulation was relatively stable when stored at $4^{\circ}C$ during 3 months. Our studies illustrated the potential use of SMEDDS for the delivery of hydrophobic compounds, such as atorvastatin, by the oral route.

Quantified Evaluation on the Qualitative Criteria for the Selection of Appropriate Concrete Slab Form-works for Residential Buildings (델파이 기법을 이용한 정성적 공법 선정 요인의 정량적 평가 분석)

  • Lee, Kyung-Suk;Lee, Tae-Hee;Shin, Young-Keun;Kim, Tae-Hyung;Han, Seung-Woo
    • Journal of the Korea Institute of Building Construction
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    • v.11 no.2
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    • pp.136-144
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    • 2011
  • The form-work operation of concrete structures is a major element determining the period and cost of construction projects. However, the selection of the appropriate form-work system is dependent on the experience of the site personnel only. In this paper, existing methods (Aluminum form, Sky deck) and new slab form-work methods (AFB: Aluminum panel Form with dropping Beam) were selected. Each method was estimated by means of Delphi techniques based on the qualitative analysis data. This paper suggests an evaluation methodology of slab form-work application in construction sites by calculating qualitative evaluation scores. The methodology finding quantified scores of qualitative criteria can be available to be applied to other construction operation evaluation methods.

A Study on Digital design process of the materialization of Free form Design Architecture (비정형 건축 구현을 위한 디지털 디자인 프로세스에 관한 연구)

  • Lee, Jae-Kook;Lee, Kang-Bok
    • Journal of The Korean Digital Architecture Interior Association
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    • v.11 no.2
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    • pp.13-19
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    • 2011
  • Starting in modern times by Le Corbusier, architectures made by concretes are still developing in these times. For several decades, the shape of box architecture has been the most familiar type of buildings. Of course "The concrete is the type of box building" isn't always right, but what we have most seen was the buildings which has been stylized and made by concretes. Through modern times to these days based on international style and functionalism, the type of box building was the most effective and good profit type of architecture which has not disregarded the capitalism. Free-form building are becoming a common place, and many of these are designed and constructed using sophisticated techniques. The main technique being used is Generative Technology of Form for free-form construction. People's interest is growing in this, and it is becoming widely used both abroad and domestically. The purpose of this paper is to investigate the use of Generative Technology of Form which is a digitally adapted design methodology in architecture. The digital design process used for contemporary buildings share many typical features that exist within a standard digital template, but also an increasing amount of mass customization that has to be produced at an additional cost. This paper will summarize these features in terms of free-form architecture, and in terms of the digital design process. In fact, 3D models have to be conceded as main design products considering features of Free Form Design Architecture. However it is practical to design twice over, because all forms of architectural drawings are 2D. From now on, design of Free Form Design Building is not to separate between design process and practical process, but to compound them as unified design system applied the process to communicate information interactively. For this, it should be required to impose unified digital design process and perform researches about effective way to apply in the field of Free-form Design Architecture.

Realization and Canonical Representation of Linear Systems through I/O Maps

  • Fadali, M. Sami;Oloomi, Hossein M.
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1593-1598
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    • 2004
  • In this paper, we use the input and output maps and develop simple procedures to obtain realizations for linear continuous-time systems. The procedures developed are numerically efficient and yield explicit formulae for the state space matrices of the realization in terms of the system parameters, notably the system modes. Both cases of the systems with distinct modes and repeated modes are treated. We also present a procedure for converting a realization obtained through the input or output map into the Jordan canonical form. The transformation matrices required to bring the realization into the Jordan canonical form are specified entirely in terms of the system modes.

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Connected Korean Digit Recognition Using Neural Networks and Lexical Analysis (신경망과 구문분석을 이용한 한국어 연결 숫자음 인식)

  • 이종석;이상욱
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.12
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    • pp.21-30
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    • 1993
  • In this paper, we propose a connected Korean digit recohnition system employing neural networks and lexical constraints of the Korean digits. In the proposed recognition system, firstly, each frame of digit string is labelled by phoneme classification neural networks.which are trained with the reference phoneme segments extracted form an isolated digit based on the position information. And, the frame labels are combined with each other for constructing the phoneme segments. Then, these segments are combined to form a digit candidate using the digit combination rules. The digit candidate is decided based on the condition for digit decision. If the condition is not satisfied, the digit candidate is further recognized using the digit decision neural network in the next step. In our approach, the neural networks are trained with 10 isolated digits uttered by 5 male speakers. To investigate the performance of the proposed recognition system, an intensive computer simulation on the 30 connected digit strings uttered by 5 male speakers is performed. The simulation result indicates that 95.6% digit recognition rate and 82% digit string recognition rate are provided by the proposed Korean digit recognition system.

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Evaluation of slope stability with Fabric Form (섬유거푸집을 적용한 비탈면의 안정성 평가)

  • Ahn, Kwang-Kuk;Choi, Young-Keun
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.10a
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    • pp.689-697
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    • 2005
  • The soil nailing system at permanent slope reinforcement is used with various facing methods in Korea. Also, pressure-injected grout technique is variously applied to many structures. However, most design of the pressure-injected grout technique have been carried out empirically because of complicated mechanisms associated with the behavior of surrounding soils and the hardening process of cement grout. Therefore this study, a newly modified soil nailing technology named as the PGSN (Pressure Grouting Soil Nailing) system with fabric form is developed to increase the global stability. Up to now, the PGSN system has been estimated mainly focusing on an establishment of the design procedure. In the present study, numerical study are carried out to evaluate potential failure surface and minimum factor of safety including facing stiffness and expanded radius of cemented grout by SSR (Shear Strength Reduction) technique. Also, results of numerical analysis are carried out for the typical section of soil nails slope using $FLAC^{2D}$ program for expanded effective radius by pressure grouting.

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A New Robust Integral Variable Structure Controller for Uncertain More Affine Nonlinear Systems with Mismatched Uncertainties (부정합조건 불확실성을 갖는 비선형 시스템을 위한 새로운 강인한 적분 가변 구조 제어기)

  • Lee, Jung-Hoon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.6
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    • pp.1173-1178
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    • 2010
  • In this note, a systematic design of a new robust nonlinear integral variable structure controller based on state dependent nonlinear form is presented for the control of uncertain more affine nonlinear systems with mismatched uncertainties and matched disturbance. After an affine uncertain nonlinear system is represented in the form of state dependent nonlinear system, a systematic design of a new robust nonlinear integral variable structure controller is presented. To be linear in the closed loop resultant dynamics and remove the reaching phase problems, the linear integral sliding surface is suggested. A corresponding control input is proposed to satisfy the closed loop exponential stability and the existence condition of the sliding mode on the linear integral sliding surface, which will be investigated in Theorem 1. Through a design example and simulation studies, the usefulness of the proposed controller is verified.