• Journal of environmental and Sanitary engineering
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• v.17 no.1
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• pp.69-74
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• 2002

This study explored for treatment processes by investigating the treatment efficiency and reaction mechanism through oxidation reaction using UV and $O_3$ as oxidant in compensate the wastewater containing nitrobenzene that is non biodegradable organic. Also by modeling these reactions, we try to step explanation of optimum reaction rate and reaction mechanism as the development of the computer program predictable the reaction rate by modeling the reaction. By using this model, after kinetic constant for each reaction from an experimental data is made an optimization and for hardly contribute to reaction rate in reaction kinetic equation is made an ignorance and suppose the simplified reaction mechanism, examined the propriety of computer simulation model and simplified reaction mechanism by comparing and inspecting the reaction kinetic constant and masstransfer coefficient. An investigation results for destructional treatment of nitrobenzene in the wastewater as non-biddegradable organic using UV, $O_3{\;}O_2{\;}H_2O_2-UV$ as oxidant.

• Earthquakes and Structures
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• v.10 no.6
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• pp.1405-1428
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• 2016

Besides the complex instructions of guidance documents for seismic rehabilitation of existing buildings, some institutions have provided simple criteria in terms of simplified rehabilitations. ASCE 41-06 is one of documents that introduced a simple method for assessment of certain buildings that do not require advanced analytical procedures. Furthermore the New Zealand guideline has presented a simple lateral mechanism analysis that is a hand static analysis for determining the probable collapse mechanism, lateral strength and displacement capacity of the structure. The present study is focused on verifying the results of the simplified methods which is used by NZSEE and ASCE 41-06 in assessment of existing buildings. For this, three different special steel moment and braced frames are assessed under these two guidelines and the accuracy of the results is checked with the results of nonlinear static and dynamic analysis. After comparison of obtained results, suggestions are presented to improve seismic retrofit criteria.

• Magazine of korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.101-112
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• 2019

This case study presented a simplified failure mechanism approach used as a preliminary deformation prediction for the Mexico City's metro system expansion. Because of the Mexico City's difficult subsoils, Line 12 project was considered one of the most challenging projects in Mexico. Mexico City's subsurface conditions can be described as a multilayered stratigraphy changing from soft high plastic clays to dense to very dense cemented sands. The Line 12 trajectory crossed all three main geotechnical Zones in Mexico City. Starting from to west of the City, Line 12 was projected to pass through very dense cemented sands corresponding to the Foothills zone changing to the Transition zone and finalizing in the Lake zone. Due to the change in the subsurface conditions, different constructions methods were implemented including the use of TBM (Tunnel Boring Machine), the NATM (New Austrian Tunneling Method), and cut-and-cover using braced Diaphragm walls for the underground section of the project. Preliminary crown and excavation front deformations were determined using a simplified failure mechanism prior to performing finite element modeling and analysis. Results showed corresponding deformations for the crown and the excavation front to be 3.5cm (1.4in) and 6cm (2.4in), respectively. Considering the complexity of Mexico City's difficult subsoil formation, construction method selection becomes a challenge to overcome. The use of a preliminary results in order to have a notion of possible deformations prior to advanced modeling and analysis could be beneficial and helpful to select possible construction procedures.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.1
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• pp.31-38
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• 2016

In this paper, the deformation-energy curves of the plastic hinges and the vessel bow, which are the major energy dissipation mechanism of a pile protective structures, were estimated, and the parametric study was performed by using those curves to apply the simplified collision model which developed in the previous study. Considered parameters were the mass of slab, the number of piles, the mass of vessel and the collision speed. As results, the difference of energy dissipation mechanism of two pile types (filled and non-filled) were revealed, and the collision behaviors of the protective structures could be tuned by the control of the inertia mass of capping slab. Therefore the simplified collision model can be used in a primary design and optimal design.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1049-1052
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• 1998

A new simplified circuit model for the switching noise analysis of the complicated multi-layer IC package is developed. The current flowing mechanism on the ground and power planes of the package is simplified by using the dependent current soures and partial plane circuit model. The methodology is very cost-efficient as well as accurate. It is demonstrated that the nosie based on the simplified circuit model has an excellent agreement with that of the complicated full circuit model. However, the simplified model takes only 5 minutes for the switching noise simulation, while the full circuit model takes more than 4 hours.

• Explosives and Blasting
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• v.39 no.3
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• pp.1-14
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• 2021

Rockburst is a sudden and violent failure of rock. During the failure process, excess energy is liberated as seismic energy, which in turn causes the surrounding rock mass to vibrate. The level of the ground vibration can reach a magnitude of over 4.5 in the Richter local scale. Thus, a rockburst can cause not only injury to persons, but also damage to both underground workings and surface structures. In this paper the source mechanism of rockburst is analyzed based mainly on the two reports of the Canadian Rockburst Research Program (CRRP). A simplified LS-DYNA modeling is also performed to identify the tensile failure patterns occurring in the remaining rock mass right after blasting in mine stope. The configuration of the simplified model will probably be useful in small-scale laboratory tests for investigating the source mechanism of rockburst.

• Structural Engineering and Mechanics
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• v.81 no.4
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• pp.513-522
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• 2022

Steel-concrete composite segments replacing the conventional reinforced concrete segments can provide the rectangular shield tunnel superiorities on bearing capacity, ductility and economy. A simplified model with high-efficiency on computation is proposed for investigating the nonlinear response of the rectangular tunnel lining composed of composite segments. The simulation model is developed by an assembly of nonlinear fiber beam elements and spring elements to express the transfer mechanism of forces through components of composite segments, and radial joints. The simulation is conducted with the considerations of material nonlinearity and geometric nonlinearity associated with the whole loading process. The validity of the model is evaluated through comparison of the proposed nonlinear simulation with results obtained from the full-scale test of the segmental tunnel lining. Furthermore, a parameter study is conducted by means of the simplified model. The results show that the stiffness of the radial joint at haunch of the ling and the thickness of inner steel plate of segments have remarkable influence on the behaviour of the lining.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.10a
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• pp.65-74
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• 1998

In seismic design procedure of precast concrete structure, it is important to assign ductility requirement on the connection element for a favorable failure mechanism. The purpose of this paper is to propose a simplified procedure to determine the required ductility of coupling beam in coupled precast shear wall for a lateral displacement ductility at the top of a structure. This study shows that an equation for ductility of cloupling beam is introduced on the basis of several basic assumption.

• Structural Engineering and Mechanics
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• v.56 no.6
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• pp.983-1001
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• 2015

This study focuses on the load carrying capacity and the force transfer mechanism of multi-hole perfobond shear connectors in steel-concrete composite structure. The behavior of multi-hole perfobond shear connector is more complicated than single-hole connector cases. 2 groups push-out tests were conducted. Based on the test results, behavior of the connection was analyzed and the failure mechanism was identified. Simplified iterative method and analytic solution were proposed based on force equilibrium for analyzing multi-hole perfobond shear connector performance. Finally, the sensitivity of design parameters of multi-hole perfobond shear connector was investigated. The results of this research showed that shear force distribution curve of multi-hole perfobond shear connector is near catenary. Shear forces distribution were determined by stiffness ratio of steel to concrete member, stiffness ratio of shear connector to steel member, and number of row. Efficiency coefficient was proposed to should be taking into account in different limit state.

• Proceedings of the Korea Information Processing Society Conference
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• 2024.05a
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• pp.137-140
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• 2024

가상 및 증강현실(VR/AR), 원격 제어, 산업 자동화를 위한 실시간 애플리케이션이 증가함에 따라 무선 통신 네트워크의 처리량과 지연시간 성능이 중요해졌다. 이에 따라 Wi-Fi 8 에서는 초고신뢰 (Ultra-High Reliable, UHR)을 목표로 표준화가 진행 중이며 다수의 AP가 협력하여 데이터를 전송하는 다중 AP 협력 기법이 핵심 기술로 논의되고 있다. 하지만 기존의 다중 AP 협력 환경에서 협력 전송을 위한 제어 정보로 인한 간섭 증가와 OBSS(Overlapped Basic Service Set) 간섭 문제를 고려하지 못하고 있다. 따라서 본 논문에서는 효율적인 다중 AP 협력 전송을 위한 단순화된 채널 관리 방법(Simplified Channel Management Mechanism, SCMM)을 제안한다. 실험 결과에 따르면, SCMM 이 종래모델 대비 처리량은 평균 21.23% 증가했고, 지연시간은 평균 51.02% 감소했다.