• Title/Summary/Keyword: static studies

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Formal Semantics for Processing Exceptions (예외 처리를 위한 형식 의미론)

  • Han, Jung-Lan
    • The KIPS Transactions:PartA
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    • v.17A no.4
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    • pp.173-180
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    • 2010
  • To specify a formal semantics is to do a significant part for design, standardization and translation of programming languages. The existing studies of a formal semantics for Java have a weak point to describe a clear and practical semantics for an efficient translation. It is necessary to do research for a formal semantics to specify a static and dynamic semantics clearly in order to do an efficient translation. This paper presents the improved Action Equation that specifies a formal semantics for Java to extend the research using Action Equation. The Action Equation is a practical and accurate specification that describes object-oriented programming features and handles exceptions. The specified Action Equation is compared to other descriptions, in terms of readability, modularity, extensibility, and flexibility and then we verified that Action Equation is superior to other formal semantics.

Application of the Method of Caustics into Anisotropic Materials (이방성재료에 대한 코스틱스법의 적용)

  • 백명철;최선호;황재석;김원현
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.12
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    • pp.2226-2240
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    • 1992
  • This paper studies the applicability of the method of caustics into anisotropic materials under mode I and mixed static loading conditions and introduces the procedure to obtain stress intensity factors(S.I.F.) in anisotropic materials by the method of caustics. The mapping equations for initial and caustic curves in anisotropic materials were introduced and their computer graphical images were compared to the experimental ones to check the validity of the mapping equations proposed in this paper. The agreement between them was found to satisfactory. Two kinds of method to determine S.I.F. in anisotropic materials by the method of caustics were proposed in this paper and applied into the orthotropic materials under various loading conditions. In the case of mode I loading condition, the S.I.F.'s obtained by this paper's methods were found to be quite similar to the results by other method, boundary element method(B.E.M) and in the case of mixed loading condtion, the S.I.F's by this paper and B.E.M. showed a little differences(2.2-24.4%) with respect to the slanted angle of crack.

Deflections, stresses and free vibration studies of FG-CNT reinforced sandwich plates resting on Pasternak elastic foundation

  • Bendenia, Noureddine;Zidour, Mohamed;Bousahla, Abdelmoumen Anis;Bourada, Fouad;Tounsi, Abdeldjebbar;Benrahou, Kouider Halim;Bedia, E.A. Adda;Mahmoud, S.R.;Tounsi, Abdelouahed
    • Computers and Concrete
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    • v.26 no.3
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    • pp.213-226
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    • 2020
  • The present study covenants with the static and free vibration behavior of nanocomposite sandwich plates reinforced by carbon nanotubes resting on Pasternak elastic foundation. Uniformly distributed (UD-CNT) and functionally graded (FG-CNT) distributions of aligned carbon nanotube are considered for two types of sandwich plates such as, the face sheet reinforced and homogeneous core and the homogeneous face sheet and reinforced core. Based on the first shear deformation theory (FSDT), the Hamilton's principle is employed to derive the mathematical models. The obtained solutions are numerically validated by comparison with some available cases in the literature. The elastic foundation model is assumed as one parameter Winkler - Pasternak foundation. A parametric study is conducted to study the effects of aspect ratios, foundation parameters, carbon nanotube volume fraction, types of reinforcement, core-to-face sheet thickness ratio and types of loads acting on the bending and free vibration analyses. It is explicitly shown that the (FG-CNT) face sheet reinforced sandwich plate has a high resistance against deflections compared to other types of reinforcement. It is also revealed that the reduction in the dimensionless natural frequency is most pronounced in core reinforced sandwich plate.

Numerical Study on the Hydrodynamic Performance Prediction of a Turbopump Inducer (인듀서 성능예측에 대한 수치해석적 연구)

  • Choi, Chang-Ho;Hong, Soon-Sam;Kim, Jin-Han
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.31 no.6
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    • pp.72-78
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    • 2003
  • In the present paper, computational studies on the hydrodynamic behavior of the inducer for the rocket-engine turbopump are presented including the effect of the mass flow rate. As the mass flow rate is increased, the inducer showed better performance with weak back flows which may have deleterious effects upon the anti-cavitation ability. But the adopted inducer showed low head rise with high volume flow rates, which may be caused by the small passage area near the trailing edge. The static pressure distributions at the shroud surface are compared with experimental results showing very good agreements except near the leading edge where strong back flows are present. The overall performance of the inducer such as, efficiency, head rise is also compared with experiments. The computational results are generally in good agreements with experimental ones near the design point, but two results show discrepancy at the high flow rate.

Color Application on Sign System Typography for Dynamic Expression (색채를 활용한 사인시스템 활자의 동적표현 연구)

  • Park, Seong-Hyeon;Kim, Young-Kook
    • The Journal of the Korea Contents Association
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    • v.7 no.4
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    • pp.250-258
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    • 2007
  • Typography is the combination of language of formative art. It is indeed the core means of human communication through understanding of language and formative values. Studies began on introduction of various techniques to overcome the phenomenon of the 'reaction of language', which appears as an impediment in delivery and sharing of information as the most fundamental roles. Successively, mobile printing types more readable and effective in delivering of meanings have been developed, thus widely distributed for general use. However, although such printing types might be easily used in image and digital media, such as in computer monitors, screens and mobile phone LCDs, etc., it is in fact difficult to use these printing types in printed surfaces, the traditional medium of information delivery, or in sign systems frequently encountered in our surrounding environment. As a solution for this, it is intended to create an effect of communication closer to dynamic typography expression by approaching visual message delivery system from the essence and substance of the color application, which corresponds to the visual spatial expression effect, the core element of expression in dynamic typography to possess significantly more powerful effect in terms of both message delivery capacity and readability than the conventional means of static typography.

The Effects of City Brand Image on City Brand Recognition and City Loyalty (도시 브랜드 이미지가 도시 브랜드 인지도와 도시 충성도에 미치는 영향)

  • Kim, Do-Heon
    • The Journal of Industrial Distribution & Business
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    • v.9 no.3
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    • pp.69-79
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    • 2018
  • Purpose - Competition among cities around the world are rapidly shifting from competition of production factors such as labor costs and quality of raw materials to competition between the consumption factors such as quality of life, settlement environment, culture, and place. The entry into the era of competition between consumption factors is not only attracting investment for strengthening city competitiveness, but also actively inducing urban image reconstruction and new image making. Therefore, various studies related to urban marketing are being carried out. The object of this study is to investigate the effect of city brand image on city brand recognition and city loyalty based on the questionnaire of external citizens about Changwon city. Research design, data, and methodology - The data were collected from 200 Seoul and Busan citizens. Reliability and exploratory factor analysis were conducted through the SPSS program, and confirmatory factor analysis and structural equation modeling were conducted by using the AMOS program. Results - As a result of the hypothesis test, six hypotheses were adopted among the nine hypotheses. In summary, pleasant image, dynamic image, and good administrative image have a significant positive impact on city brand recognition. The magnanimous image did not have a significant effect on city brand recognition. In the impact of city brand image on city loyalty, magnanimous image and good administrative image had significant positive impact on city loyalty. Pleasant images and dynamic images did not significantly affect city loyalty. In addition, city brand recognition positively influenced city loyalty. Conclusions - First, it is possible to say that there is an academic significance of this research in its contribution to regional revitalization by investigating mutual influences in urban aspect by combining place marketing with image, recognition, and loyalty. Secondly, kinetic images such as pleasant image and dynamic image have more influence on recognition, and static images such as magnanimous images have more influence on loyalty. So, further research will be necessary to establish theories. Finally, In order to increase city brand recognition and city loyalty to local city, efforts should be made to improve urban images such as pleasant image, magnanimous image, dynamic image, and good administrative image.

Structural damage detection through longitudinal wave propagation using spectral finite element method

  • Kumar, K. Varun;Saravanan, T. Jothi;Sreekala, R.;Gopalakrishnan, N.;Mini, K.M.
    • Geomechanics and Engineering
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    • v.12 no.1
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    • pp.161-183
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    • 2017
  • This paper investigates the damage identification of the concrete pile element through axial wave propagation technique using computational and experimental studies. Now-a-days, concrete pile foundations are often common in all engineering structures and their safety is significant for preventing the failure. Damage detection and estimation in a sub-structure is challenging as the visual picture of the sub-structure and its condition is not well known and the state of the structure or foundation can be inferred only through its static and dynamic response. The concept of wave propagation involves dynamic impedance and whenever a wave encounters a changing impedance (due to loss of stiffness), a reflecting wave is generated with the total strain energy forked as reflected as well as refracted portions. Among many frequency domain methods, the Spectral Finite Element method (SFEM) has been found suitable for analysis of wave propagation in real engineering structures as the formulation is based on dynamic equilibrium under harmonic steady state excitation. The feasibility of the axial wave propagation technique is studied through numerical simulations using Elementary rod theory and higher order Love rod theory under SFEM and ABAQUS dynamic explicit analysis with experimental validation exercise. Towards simulating the damage scenario in a pile element, dis-continuity (impedance mismatch) is induced by varying its cross-sectional area along its length. Both experimental and computational investigations are performed under pulse-echo and pitch-catch configuration methods. Analytical and experimental results are in good agreement.

The Effects of Core Program Exercise on Balance in Patients with Chronic Low Back Pain (코어 프로그램 운동이 만성요통 환자의 균형에 미치는 영향)

  • Choi, Won-Jye;Park, Beom-Seok;Yoo, Byung-Kook;Jeon, Jae-Keun;Son, Kyung-Hyun
    • Journal of Korean Physical Therapy Science
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    • v.25 no.1
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    • pp.1-10
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    • 2018
  • Background: The purpose of this study was to ascertain the effects of core program exercise on balance in patients with chronic low back pain. Thirty-four subjects participated in this study, these subjects were assigned into two groups, a control group(n=17) and an experimental group(n=17). Methods: The subjects in the control group were received a conservative physical therapy and in the experimental group carried out the core program exercise for 30 minutes per day, three times a week during 6 weeks. In order to evaluate the progresses of balance ability, corresponding variables were measured at two times, pre and 6th week. The balance ability was assessed using GOOD BALANCE system. The collected data were analyzed by using the paired t-test and ANCOVA. In all statistical analyses, significance level, ${\alpha}$ was set by 0.05. Results: The results of this study were as follows: 1) In the position of left standing eye closed, there were significant difference of Y in the control group and X, Y, V in the experimental group. 2) In the position of right standing eye closed, there were significant difference of Y in the control group and X, Y, V in the experimental group. 3) In the position of dynamic balance 1, there were significant difference APV in experimental groups. 4) In the position of dynamic balance 2, there were significant difference MLV in experimental groups. 5) There were significances between the two group of X, V in static balance and APV in dynamic balance. Conclusion: The above results indicated that a core program exercise improved balance abilities in patients with chronic low back. The further studies should be focused at development of various modified forms of the core program exercise in keeping up the improvement effect of this exercise.

Studies on the Development of the Automatic Blood Analyzer with Silicone Rubber-Based Solid-State $K^+$- and $Na^+$-Selective Electrodes (실리콘러버 지지체의 $K^+$$Na^+$ 선택성 고체형 전극을 이용한 자동혈액분석기의 개발에 대한 연구)

  • Kang, Myung-Sung;Jeon, Woo-Sung;Kim, Sun-Kwan;Kim, Dea-Hoon;Cha, Geun-Sig;Nam, Hak-Hyun;Cho, Han-Ik;Park, Sung-Sup
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.11
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    • pp.26-33
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    • 1995
  • Silicone Rubber (SR)-based potassium- and sodium-selective solid-state electrodes have been developed for the portable blood electrolyte analyzer system. The electrochemical performance of these electrodes have been evaluated with a static experimental setup and with the newly developed blood electrolyte analyzer system (model; HS603). It has been shown that their potentiometric properties are essentially comparable to those of PVC-based ion-selective electrodes, but with greatly improved lifetime (200 and 40 days for potassium and sodium sensors, respectively) and potential stability (within $\pm0.1$ mV). Clinical tests have been performed with real serum samples and the results have been compared with those obtained from Ciba-Corning BGA 288 system; correlations were excellent, proving its practical utility as a new commercial system.

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Improvement of the Avoidance Performance of TCAS-II by Employing Kalman Filter (Kalman Filter를 적용한 TCAS-II 충돌회피 성능 개선)

  • Jun, Byung-Kyu;Lim, Sang-Seok
    • Journal of Advanced Navigation Technology
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    • v.15 no.6
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    • pp.986-993
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    • 2011
  • In this paper we consider the problem of the existing TCAS-II systems that fail to be satisfactory solution to mid-air collisions (MACs) and near mid-air collisions (NMACs or near misses). This is attributed to the fact that the earlier studies on the collision avoidance mainly have focused on determination logic of avoidance direction and vertical speed, reversal of the avoidance direction, multiple aircraft geometry, and availability in certain air spaces. But, the influence of sensor measurement errors on the performance of collision avoidance was not properly taken into account. Here we propose a new TCAS algorithm by using Kalman filter instead of '${\alpha}-{\beta}$' tracker to improve the avoidance performance under the influence of barometric sensor errors due to air-temperature, pressure leaks, static source error correction, etc.