• Title/Summary/Keyword: Anti- Design

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Longitudinal anti-cracking analysis for post-tensioned voided slab bridges

  • Zhou, Zhen;Meng, Shao-Ping;Liu, Zhao
    • Structural Engineering and Mechanics
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    • v.43 no.4
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    • pp.459-473
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    • 2012
  • Post-tensioned concrete voided slab girders are widely used in highway bridge constructions. To obtain greater section hollow rate and reduce the self-weight, the plate thickness of slab girders are designed to be small with the adoption of flat anchorage system. Since large prestress is applied to the anchor end section, it was found that longitudinal shear cracks are easy to occur along the voided slab girder. The reason is the existence of great shearing effect at the junction area between web and bottom (top) plate in the anchor end section. This paper focuses on the longitudinal anti-cracking problem at the anchor end of post-tensioned concrete voided slab girders. Two possible models for longitudinal anticracking analysis are proposed. Differential element analysis method is adopted to derive the solving formula of the critical cracking state, and then the practical analysis method for longitudinal anti-cracking is established. The influence of some factors on the longitudinal anti-cracking ability is studied. Results show that the section dimensions (thickness of bottom, web and top plate) and prestress eccentricity on web plate are the main factors that influence the anti-cracking ability. Moreover, the proposed method is applied into three engineering examples to make longitudinal anti-cracking verification for the girders. According to the verification results, the design improvements for these girders are determined.

The Anti-consumption Effect on the Car Sharing Utility: The Moderating Effect of Brand Luxury Level

  • LEE, Hee-Jung
    • Journal of Distribution Science
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    • v.18 no.6
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    • pp.63-75
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    • 2020
  • Purpose: This study examines the motivations that prompt customers to use commercial sharing services (CSSs), and the relationship between anti-consumption and the perceived utility of CSSs in the fashion-sharing business. This study tries to understand how the two types of anti-consumption can differentially affect consumers' perceived utility to use CSSs. In particular, as the types of CSS have diversified and many consumers have used them, it can be expected that the influence of anti-consumption on the perceived utility of CSSs can change, depending on the field where the CSS is applied. Research design, data and methodology: The structural equation modeling (SEM) with the SPSS 22.0 and AMOS 18.0 programs was used. Results: This study found that (i) two types of anti-consumption (voluntary and selective) differentially affect the perceived utilities to use CSSs; (ii) the two types of anti-consumption differentially affect the perceived utility to use CSSs depending on the level of the brand. Conclusions: In order to promote the spread of consumers' use in the sharing economy, it will be possible to identify what important utility is and make a meaningful contribution to the establishment of future marketing strategies.

The Formation of Resistance on Multi-culture Social Emotion and Countermeasures in Korea

  • Kim, Bo-Suk;Kim, Yeong-Ok;Jung, Myung-Hee
    • Journal of Distribution Science
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    • v.15 no.1
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    • pp.21-30
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    • 2017
  • Purpose - These days, Korean society with more than 2 million foreigners has made multi-cultural society quickly. Multi-cultural society has become popular and anti multi-cultural phenomenon has grown up gradually against Korea's traditional habits. Research design, data, and methodology - European countries that were said to be multi-cultural society had suffered from terror, riot and other social conflicts. The study examined Koreans' racism and anti multi-cultural emotion to investigate the conditions and causes of anti multi-cultural emotion. Further, this study investigates a prevention of the worst case such as Norway terror and the countermeasures compared to each country's social customs. Results - Koreans are not generous to the foreigners. Foreign countries' cases after failures in multi-cultural society might give future implications on multi-cultural society in Korea. Conclusions - Korean society have not produced new one by introducing another races, nationality and culture not cognizing failure experiences of multi-culturalism like Europe. Nonetheless, Korean society shall not give up multi-culturalism. Korean society shall prepare for multi-culturalism society to lessen social conflict as much as possible and not to neglect anti culturalism emotion producing social conflict, and shall investigate the related causes to lessen anti multi-culturalism emotion and to integrate Korean style of multi-culturalism society for Korea as a tool of nation management.

Numerical Investigation of Anti-Diffusion Source Term for Free-Surface Wave Flow

  • Park, Sunho;Lee, Heebum;Rhee, Shin Hyung
    • Journal of Advanced Research in Ocean Engineering
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    • v.2 no.2
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    • pp.48-60
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    • 2016
  • Accurate simulation of free-surface wave flows around a ship is very important for better hull-form design. In this paper, a computational fluid dynamics (CFD) code which is based on the open source libraries, OpenFOAM, was developed to predict the wave patterns around a ship. Additional anti-diffusion source term for minimizing a numerical diffusion, which was caused by convection differencing scheme, was considered in the volume-fraction transport equation. The influence of the anti-diffusion source term was tested by applying it to free-surface wave flow around the Wigley and KCS model ships. In results, the wave patterns and hull wave profiles of the Wigley and KCS model ships for various anti-diffusion coefficients showed quite close patterns. While, the band width of the water volume-fraction values between 0.1 to 0.9 at the Wigley and KCS model hull surfaces was narrowed by considering the anti-diffusion term. From the results, anti-diffusion source term decreased free-surface smearing.

Gender Differences Regarding Parental Teasing of Korean Children's Weight and Anti-Fat Attitudes

  • Ra, Jin Suk;Cho, Kyung Seu;Cho, Yoon Hee
    • Journal of Korean Public Health Nursing
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    • v.34 no.2
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    • pp.289-300
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    • 2020
  • Purpose: This study aimed to identify gender differences associated with weight related teasing by parents, and development of anti-fat attitudes among Korean children aged 5 to 7 years. Methods: This study used a descriptive cross-sectional design. Questionnaire interviews were conducted by enrolling 222 healthy children having normal development and living with their parents in South Korea. Results: Results showed gender and parental weight-related teasing was significantly associated with anti-fat attitudes among children. Significance of the association between parental weight-related teasing and anti-fat attitudes among kindergarten children differed according to the child's gender. Among girls, the higher level of parental weight-related teasing was associated with greater anti-fat attitude. However, parental weight-related teasing was not associated with increased anti-fat attitude among boys. Conclusion: Considering our study results, we recommend developing programs aimed towards decreasing teasing in the family environment, such as changing the gender-specific weight norms to prevent anti-fat attitudes in Korean girls.

The Effect of Debt Characteristics on the Relationship between Anti-Takeover Provision and the Cost of Debt (부채특성이 경영권방어수단과 타인자본비용 간의 관계에 미치는 영향)

  • A-Young Lee;Sung-Hye Kim
    • Asia-Pacific Journal of Business
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    • v.14 no.3
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    • pp.205-219
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    • 2023
  • Purpose - This study examines the effect of corporate debt characteristics on the relationship between anti-takeover provision and the cost of debt. Design/methodology/approach - The study analyzes a sample of non-financial firms listed on the stock market with December fiscal year-end from 2011 to 2018. Debt default risk (debt size, liquidity ratio, interest coverage ratio, loss occurrence) and the issuance of bonds are utilized as measures of corporate debt characteristics. Findings - First, it is observed that creditors of firms with anti-takeover provision demand higher returns as the debt default risk of these firms increases. Second, for firms issuing bonds, it is found that bondholders in companies with anti-takeover provision also seek higher returns. Research implications or Originality - This study contributes by demonstrating that the effect of anti-takeover provision on creditors can vary depending on corporate debt characteristics. Particularly, the study highlights the importance of a firm's debt default risk and creditor distinction (bondholders vs. regular creditors) as significant factors that may influence perceptions of anti-takeover provision.

Coupled Motion Simulation of the Mobile Harbor and Anti-Rolling Devices in Waves

  • Yoon, Hyeon-Kyu;Kang, Joo-Nyun;Lew, Jae-Moon;Moon, Seok-Joon;Chung, Tae-Young
    • Journal of Navigation and Port Research
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    • v.34 no.4
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    • pp.271-279
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    • 2010
  • The Mobile Harbor(MH) is a new transportation platform that can load and unload containers to and from very large container ships in the sea. This loading and unloading by crane can be performed with only very small movements of the MH in waves because MH is operated outside of the harbor. For this reason, an anti-rolling tank(ART) and an active mass driving system(AMD) were designed to reduce MH's roll motion, especially at the natural frequency of MH. In the conceptual design stage, it is difficult to confirm the design result of theses anti-rolling devices without modeling and simulation tools. Therefore, the coupled MH and anti-rolling devices' dynamic equations in waves were derived and a simulation program that can analyze the roll reduction performance in various conditions, such as sea state, wave direction, and so on, was developed. The coupled equations are constructed as an eight degrees of freedom (DOF) motion that consists of MH's six DOF dynamics and the ART's and AMD's control variables. In order to conveniently include the ART's and AMD's control dynamics in the time domain, MH's radiated wave force was described by an impulse response function derived by the damping coefficient obtained in the frequency domain, and wave exciting forces such as Froude-Krylov force and diffraction force and nonlinear buoyancy were calculated at every simulation time interval. Finally, the roll reduction performances of the designed anti-rolling devices were successfully assessed in the various loading and wave conditions by using a developed simulation program.

USN Channel Establishment Algorithm for Sensor Authentication and Anti-collision (센서 인증과 충돌 방지를 위한 USN 채널 확립 알고리즘)

  • Rhee, Kang-Hyeon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.44 no.3
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    • pp.74-80
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    • 2007
  • Advances in electronic and computer technologies have paved the way for the proliferation of WSN(wireless sensor networks). Accordingly, necessity of anti-collusion and authentication technology is increasing on the sensor network system. Some of the algorithm developed for the anti-collision sensor network can be easily adopted to wireless sensor network platforms and in the same time they can meet the requirements for sensor networks like: simple parallel distributed computation, distributed storage, data robustness and auto-classification of sensor readings. To achieve security in wireless sensor networks, it is important to be able to establish safely channel among sensor nodes. In this paper, we proposed the USN(Ubiquitous Sensor Network) channel establishment algorithm for sensor's authentication and anti-collision. Two different data aggregation architectures will be presented, with algorithms which use wavelet filter to establish channels among sensor nodes and BIBD (Balanced Incomplete Block Design) which use anti-collision methods of the sensors. As a result, the proposed algorithm based on BIBD and wavelet filter was made for 98% collision detection rate on the ideal environment.

Design and Properties Related to Anti-reflection of 1.3μm Distributed Feedback Laser Diode (1.3μm 분포 괴환형 레이저 다이오드의 무반사 설계 및 특성)

  • Ki, Hyun-Chul;Kim, Seon-Hoon;Hong, Kyung-Jin;Kim, Hwe-Jong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.3
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    • pp.248-251
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    • 2009
  • We have investigated the effect of the quality of 1.3 um distributed feed back laser diode (DFB-LD) on the design of anti-reflection (AR) coatings. Optimal condition of AR coating to prevent internal feedback from both facets and reduce the reflection-induced intensity noise of laser diode was simulated with Macleod Simulator. Coating materials used in this work were ${Ti_3}{O_5}$ and $SiO_2$, of which design thickness were 105 nm and 165 nm, respectively. AR coating films were deposited by Ion-Assisted Deposition system. The electrical and optical properties of 1.3 um laser diode were characterized by Bar tester and Chip tester. Threshold current and slop-efficiency of DFB-LD were 27.56 mA 0.302 W/A. Far field pattern and wavelength of DFB-LD were $22.3^{\circ}(Horizontal){\times}24.4^{\circ}$ (Vertical), 1313.8 nm, respectively.

Position and swing angle control for loads of overhead cranes (천정크레인 부하의 위치 및 흔들림 제어)

  • Lee, Ho-Hoon;Cho, Sung-Kun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.2
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    • pp.297-304
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    • 1997
  • This paper presents a systematic design method of an anti-swing control law for overhead cranes. A velocity servo system for the trolley of a crane is designed based on the dynamics of the trolley and its load. The velocity servo system compensates for the effects of load swing on the trolley dynamics so that the velocity servo is independent of load swing. The velocity servo system is used for the design of a position servo system for the trolley via the loop shaping method. The position servo system and the swing dynamics of the load are then used to design an angle control system for load swing based on the root locus method. The combined position servo and the angle control systems constitute the overall control system. In the presence of low frequency disturbances, the proposed control law guarantees accurate position control for the trolley and fast damping for load swing. Furthermore, the performance of the proposed control law is independent of the mass of the load. Experimental results on a prototype crane show the effectiveness of the proposed anti-swing control law.