• Title/Summary/Keyword: Link capacity

Search Result 545, Processing Time 0.027 seconds

Evaluation of Structural Behavior of Precast-Concrete Column and H-Beam using Non-linear Finite Element Analysis (비선형 유한요소해석을 이용한 PC 기둥-H 형강보의 구조거동 분석)

  • Park Jeong-sim;Park Soon-kyu
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2004.11a
    • /
    • pp.425-428
    • /
    • 2004
  • Nonlinear finite element analysis is conducted to predict the structural behavior of precast concrete column and steel beam connected by using bolted connections. The Nonlinear FEM program is based on the modified compression field theory which has good accuracy in the concrete structures. The link element is properly used to model the discontinuity between precast concrete column and steel beam. Predictions from the proposed model are compared with experimental results and it is concluded that structural behaviors of the composite structures, such as strength capacity, crack pattern and failure mode, can be predicted quite successfully.

  • PDF

A Simple Approach for Determining No-Passing Zones in Two-Lane Rural Highways

  • Son, Bong-Soo
    • Proceedings of the KOR-KST Conference
    • /
    • 1998.09a
    • /
    • pp.141-151
    • /
    • 1998
  • Provision of Passing Sight Distance (PSD) is an important component in two-lane highway design and has a critical impact on capacity of highway and safety of drivers. Many models have been developed to estimate PSD reasonably. However, each of them has a number of shortcomings for reflecting the real traffic conditions. This paper introduces a revised model that reflects the characteristics of the passing maneuver. The changes in passing sight distances under different assumptions about acceleration and vehicle length, which are related to vehicle types, are presented. The results obtained by the revised model are compared with those obtained from the existing models. There is an important link between geometric design decisions which determine the available sight distance and the quality of service which the road provides. In this paper, we examine one aspect of this relationship. That is to determine whether the passing sight distance is provided by improving horizontal alignment for a specific roadway section or passing may be restricted to save the road construction cost. To do so, a simple method for estimating traffic delay in no-passing is introduced.

  • PDF

DC-link Ripple Reduction of Cascaded NPC/H-bridge Converter using Third Harmonic Injection (Cascaded NPC/H-bridge 컨버터의 DC링크 리플 저감을 위한 3차 고조파 주입 기법)

  • Park, Woo-Ho;Kang, Jin-Wook;Hyun, Seung-Wook;Hong, Seok-Jin;Won, Chung-Yuen
    • Proceedings of the KIPE Conference
    • /
    • 2016.11a
    • /
    • pp.218-219
    • /
    • 2016
  • This paper present Phase Shifted with carrier based on Sinusoidal PWM(SPWM) by using Cascaded NPC/H-birdge converter. The proposed Phase Shifted PWM method is adding third harmonic injection in switching signal. The advantage of the proposed method is reducing the voltage and capacity of the capacitor. This paper compare general Phase Shifted method with proposed Phase Shifted method that added the third harmonic injection. Each PWM method is tested without considering the switching loss by using PSIM 9.1.4 simulation.

  • PDF

Parametrical study of the behavior of exterior unreinforced concrete beam-column joints through numerical modeling

  • Silva, Matheus F.A.;Haach, Vladimir G.
    • Computers and Concrete
    • /
    • v.18 no.2
    • /
    • pp.215-233
    • /
    • 2016
  • Exterior beam-column joints are structural elements that ensure connection between beams and columns. The joint strength is generally assumed to be governed by the structural element of lowest load capacity (beam or column), however, the joint may be the weakest link. The joint shear behavior is still not well understood due to the influence of several variables, such as geometry of the connection, stress level in the column, concrete strength and longitudinal beam reinforcement. A parametrical study based only on experiments would be impracticable and not necessarily exposes the failure mechanisms. This paper reports on a set of numerical simulations conducted in DIANA$^{(R)}$ software for the investigation of the shear strength of exterior joints. The geometry of the joints and stress level on the column are the variables evaluated. Results have led to empirical expressions that provide the shear strength of unreinforced exterior beam-column joints.

Evaluation of performance and seismic parameters of eccentrically braced frames equipped with dual vertical links

  • Mohsenian, Vahid;Nikkhoo, Ali
    • Structural Engineering and Mechanics
    • /
    • v.69 no.6
    • /
    • pp.591-605
    • /
    • 2019
  • Investigations on seismic performance of eccentrically braced frames equipped with dual vertical links have received little attention. Therefore, the main goal of this paper is to describe design steps for such frames and evaluate nonlinear performance of this system according to the reliability analysis. In this study, four and eight story frame structures are analyzed and the response modification factors for different intensity and damage levels are derived in a matrix form based on a new approach. According to the obtained results, the system has high ductility and acceptable seismic performance. Moreover, it is concluded that using response modification factor equal to 8 in the design of system provides desirable seismic reliability under the design and maximum probable hazard levels. Due to desirable performance and significant advantages of the dual vertical links, this system can be used as a main lateral load bearing system, in addition to its application for rehabilitation of damaged structures.

Roadmapping for the Export of Space Segment Based on Portfolio Analysis: A Case of Korea

  • Kim, Jieun
    • Asian Journal of Innovation and Policy
    • /
    • v.9 no.3
    • /
    • pp.360-393
    • /
    • 2020
  • The space industry is a comprehensive and technology-intensive industry involving different converging technologies. However, most of the companies in Korea's space industry are small and medium-sized enterprises (SMEs) and need to strengthen global capacity to export their products. However, the link between the destination country and the product remains insufficient. Consequently, the purpose of this study is to propose an export roadmap for space products to provide SMEs with export opportunities and strategic guidelines. For this, technology roadmap and portfolio analysis are applied to this purpose. This study is expected to be helpful to SMEs and government agencies.

Can antioxidants be effective therapeutics for type 2 diabetes?

  • Park, Soyoung;Park, So-Young
    • Journal of Yeungnam Medical Science
    • /
    • v.38 no.2
    • /
    • pp.83-94
    • /
    • 2021
  • The global obesity epidemic and the growing elderly population largely contribute to the increasing incidence of type 2 diabetes. Insulin resistance acts as a critical link between the present obesity pandemic and type 2 diabetes. Naturally occurring reactive oxygen species (ROS) regulate intracellular signaling and are kept in balance by the antioxidant system. However, the imbalance between ROS production and antioxidant capacity causes ROS accumulation and induces oxidative stress. Oxidative stress interrupts insulin-mediated intracellular signaling pathways, as supported by studies involving genetic modification of antioxidant enzymes in experimental rodents. In addition, a close association between oxidative stress and insulin resistance has been reported in numerous human studies. However, the controversial results with the use of antioxidants in type 2 diabetes raise the question of whether oxidative stress plays a critical role in insulin resistance. In this review article, we discuss the relevance of oxidative stress to insulin resistance based on genetically modified animal models and human trials.

A Study on Analytical Simulation Technique for Link Capacity Planning (링크 용량계획을 위한 분석적 시뮬레이션 기법 연구)

  • Jang, Taek-Soo;Han, Jung-Gyu
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2011.11a
    • /
    • pp.504-506
    • /
    • 2011
  • 네트워크 관리자는 트래픽 증가에 따른 네트워크 성능저하 문제를 해결하기 위해 개별 링크에 필요한 용량을 산정해야할 때가 있다. 대규모 네트워크의 경우 이산 사건 시뮬레이션만을 수행하여 용량을 산정하는 것보다 분석적 시뮬레이션을 함께 사용하여 용량을 산정한다면 시뮬레이션에 필요한 시간을 줄일 수 있다. 본 논문에서는 링크 용량계획을 위한 분석적 시뮬레이션의 활용방안을 논하고 그 기법을 기술하였다. 제안한 분석적 시뮬레이션 기법은 정상상태의 네트워크 분석이기 때문에 이산 사건 시뮬레이션에 비해 시뮬레이션에 소요되는 시간은 작지만 정확도는 낮다. 하지만 대규모 네트워크의 상태를 빠르게 파악하고 문제를 해결해야 한다면 좀 더 정밀한 시뮬레이션이나 분석을 위한 사전자료를 만들기에 충분할 것이다.

The Lack of Judicial Politics and Challenge of Democracy in Korea (법의 지배와 한국정치학의 빈 구멍)

  • Kang, Miongsei
    • Analyses & Alternatives
    • /
    • v.1 no.1
    • /
    • pp.3-16
    • /
    • 2017
  • This paper aims to emphasize the necessity of beginning and developing judicial politics in Korea. Law is constitutive of politics, and judicial politics is vital in understanding how politics is influenced by law. Disappointingly, social science in Korea has not recognized the importance of judicial politics. Judicial branch in Korea does not have the capacity to constrain the executive or other government agencies governed by elected officials. The rule of law does not work. Judicial politics has not yet been introduced in Korea, despite its enormous importance in shaping political economy. The rule of law and courts are believed to be the institutional foundation for economic growth. Law embodied in "no one is above the law" is recognized to provide fairness and stability with a democracy. Little attention to judicial politics results in leaving behind a missing link in a polity. The fortification of the rule of law is necessary to make democracy consolidated in Korea, as shown in impeachment of former president Park Geunhae. A new scholarship in Korea on judicial politics is in need to discuss what conditions under which the rule of law is possible and how to make it sustainable.

  • PDF

Capacity Building Programs for Emerging Countries by the Korean Regional Innovation Model: Policy Analysis and Suggestions (한국형 지역혁신모델의 신흥국 전수사업 : 정책분석과 제안)

  • Kim, Hak-Min
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.3
    • /
    • pp.75-82
    • /
    • 2018
  • Recently, emerging countries have been paying attention to Korean economic development policy, trying to adopt the Korean regional innovation model. Korea is also interested in exporting its regional innovation model and enhancing economic cooperation with those countries. This paper aims to analyze the capacity-building programs of the Korean regional innovation model for emerging countries and suggests policies for it. For this purpose, the local innovators' participation patterns in the process of collaborative learning/networking/interaction are investigated with a focused group-interview method. From an analysis of the programs supported by Korean organizations, this study finds that the correlation coefficient between the training time of capacity building and the participation rate of local members' collaborative learning is very high (0.975). Since the correlation coefficient between the participation rates of collaborative learning and networking is relatively low (0.667), a policy to link local collaborative learning to networking should be provided. As the correlation coefficient between the participation rates of networking and interaction is high (0.950), networking is a key to regional innovation. This study recommends activity programs to promote networking among local innovators, rather than training and consulting programs. As introduced in the Chungnam Techno Park case, this study suggests that the capacity-building program should include programs to initiate a collaborative learning network, to create a local-demand, regional innovation model, and to operate the regional innovation platform, which should be done by local innovators in the emerging countries.