• Title/Summary/Keyword: simple system

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A Study on Improvement of Sound Quality of Vehicle Using the Vibrational Power Flow (진동 유동해석기법을 이용한 자동차 실내소음 저감 및 음질 개선)

  • Lee, Sang-Kwon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.208-214
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    • 2000
  • Reduction of structure-borne noise of the compartment in a car is an important task in automotive engineering. Transfer path analysis using vibroacoustic reciprocity technique or multiple path decomposition method has generally been used for structure-borne noise path analysis. These methods are useful in solving particular problem but do not quantify the effectiveness of vibration isolation of each isolator of a vehicle. To quantify the effectiveness of vibration isolation, the vibrational power flow has been used for a simple isolation system or a laboratory based isolation system. It is often difficult to apply the vibrational power flow technique to the complex isolation system like a car. In this paper, a simple equation is derived for calculation of the vibrational power flow of an isolation system with multiple isolators such as a car. It is successfully applied to not only quantifying the relative contributions of eighteen isolators but also reducing structure-borne noise of a passenger car. According to the results, the main contributor of eighteen isolators is the rear roll mount of an engine. The reduced structure-borne noise level is about 5dBA.

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Detoxification Properties of Guanidinylated Polyethyleneimine Treated Polypropylene Non-woven Fabric Against Chemical Warfare Agents (구아니딘화 폴리에틸렌이민이 처리된 폴리프로필렌 부직포의 군사용 화학 작용제 제독 특성)

  • Kim, Jiyun;Kwon, Woong;Kim, Changkyu;Jeong, Euigyung
    • Textile Coloration and Finishing
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    • v.33 no.1
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    • pp.1-9
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    • 2021
  • This study aims to prepare the fabric with detoxification properties against chemical warfare agent by the simple treatment. For this purpose, polypropylene non-woven fabric(PP) was treated with polyethyleneimine(PEI) and guanidinylated PEI and detoxification properties of the guanidinylated PEI treated PP were evaluated using diisopropylfluorophosphate(DFP), as a chemical warfare agent simulant, and compared with the untreated and PEI treated PP. The half-lives of DFP on guanidinylated PEI treated PP and untreated PP were 334 min and 714 min, respectively. The half-life of DFP with guanidinylated PEI treated PP was 53.22% shorter than with untreated PP. This result shows that guanidine group in guanidinylated PEI treated PP was acted as a base catalyst for hydrolysis of DFP and decreased half-life of DFP. Therefore, it is expected that guanidinylated PEI treatment can be an simple pathway to prepare the detoxification fabric material for protective clothing against chemical warfare agents.

A pressure based flow velocity estimation technique using inverse impedance for simple pressurized pipeline systems (피압 단순 관로 체제에서의 인버스 임피던스를 이용한 수압기반 유속추정기술)

  • Lee, Jeongseop;Ko, Dongwon;Choi, Dooyong;Kim, Sanghyun
    • Journal of Korean Society of Water and Wastewater
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    • v.36 no.4
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    • pp.219-228
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    • 2022
  • In this study, we propose a flow velocity evaluation scheme based on pressure measurement in pressurized pipeline systems. Conservation of mass and momentum equations can be decomposed into mean and perturbation of pressure head and flowrate, which provide the pressure head and flowrate relationship between upstream and donwstream point in pressurized pipeline system. The inverse impedance formulations were derived to address measured pressure at downstream to evaluation of flow velocity or pressure at any point of system. The convolution of response function to pressure head in downstream valve provides the flow velocity response in any point of the simple pipeline system. Simulation comparison between traditional method of characteristics and the proposed method provide good agreements between two distinct approaches.

An equivalent linear SDOF system for prediction of nonlinear displacement demands of non-ductile reinforced concrete buildings with shear walls

  • Saman Yaghmaei-Sabegh;Shabnam Neekmanesh;Nelson Lam;Anita Amirsardari;Nasser Taghizadieh
    • Structural Engineering and Mechanics
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    • v.85 no.5
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    • pp.655-664
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    • 2023
  • Reinforced concrete (RC) shear wall structures are one of the most widely used structural systems to resist seismic loading all around the world. Although there have been several efforts to provide conceptually simple procedures to reasonably assess the seismic demands of structures over recent decades, it seems that lesser effort has been put on a number of structural forms such as RC shear wall structures. Therefore, this study aims to represent a simple linear response spectrum-based method which can acceptably predict the nonlinear displacements of a non-ductile RC shear wall structure subjected to an individual ground motion record. An effective period and an equivalent damping ratio are introduced as the dynamic characteristics of an equivalent linear SDOF system relevant to the main structure. By applying the fundamental mode participation factor of the original MDOF structure to the linear spectral response of the equivalent SDOF system, an acceptable estimation of the nonlinear displacement response is obtained. Subsequently, the accuracy of the proposed method is evaluated by comparison with another approximate method which is based on linear response spectrum. Results show that the proposed method has better estimations for maximum nonlinear responses and is more utilizable and applicable than the other one.

A Study on the Thermodynamic Cycle of OTEC system (해양 온도차발전 시스템의 열역학 사이클에 대한 연구)

  • Kim, Nam-Jin;Shin, Sang-Ho;Chun, Won-Gee
    • Journal of the Korean Solar Energy Society
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    • v.26 no.2
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    • pp.9-18
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    • 2006
  • In this paper, the thermodynamic performance of OTEC cycle was examined. Computer simulation programs were developed for simple Rankine cycle, regenerative Rankine cycle, Kalina cycle, open cycle and hybrid cycle. For the simple Rankine cycle, the results show that newly developed fluids such as R410A and R32 that do not cause stratospheric ozone layer depletion perform as well as R22 and ammonia. Also, simple Rankine cycle OTEC power plant can practically generate electricity when the difference in warm and cold sea water inlet temperatures are greater than $14^{\circ}C$. The regenerative Rankine cycle showed a 1.5 to 2% increase in energy efficiency compared to the simple Rankine cycle while the Kalina cycle employing ammonia/water mixture showed a 2-to-3% increase in energy efficiency, and the overall cycle efficiencies of hybrid cycle and open cycle were 3.35% and 4.86%, respectively.

Device Description Repository System Based on DDR Simple API

  • Cho, Yong-Soon;Lee, Young-Il;Jung, Hoe-Kyung
    • Journal of information and communication convergence engineering
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    • v.7 no.2
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    • pp.203-208
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    • 2009
  • Recently, improved capabilities of the mobile device is represented in a demand for same level services with the desktop device services but the service that is developed for desktop device is not compatible with mobile devices. To fulfill these demands, it is needed to provide services with considering features of mobile devices. This means that CP(Contents Provider) must do contents transformation in order to make suitable contents on mobile device. For managing some information that is required to do contents transformation, we need the DDR(Device Description Repository) which can store and search a variety of device information to grasp the constraints on the mobile device as compared with desktop devices. Also, defining standard API is required to offer a service regardless of platforms. Hereupon W3C(World Wide Web Consortium) introduced DDR Simple API. However that specifies the limited functions of DDR, which is inevitable to be added for more precise search services. In this paper, we expanded DDR Simple API and implemented DDR that supports DDL(Device Description Language) conversion and storing and searching device information.

After-fracture redundancy in simple span two-girder steel bridge

  • Park, Yong-Myung;Joe, Woom-Do-Ji;Hwang, Min-Oh;Yoon, Tae-Yang
    • Structural Engineering and Mechanics
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    • v.27 no.6
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    • pp.651-670
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    • 2007
  • An experimental study to evaluate a redundancy capacity in simple span two plate-girder bridges, which are generally classified as a non-redundant load path structure, has been performed under the condition that one of the two girders is seriously damaged. The bottom lateral bracing was selected as an experimental parameter and two 1/5-scale bridge specimens with and without bottom lateral bracing have been prepared. The loading tests were first performed on the intact specimens without cracked girder within elastic range. Thereafter, the ultimate loading tests were conducted on the damaged specimens with an induced crack at the center of a girder. The test results showed that the cross beams and concrete deck redistributed partly the applied load to the uncracked girder, but the lateral bracing system played a significant role of the load redistribution when a girder was damaged. The redundancy was evaluated based on the test results and an appropriate redundancy level was evaluated when the lateral bracing was provided in a seriously damaged simple span two-girder steel bridge.

A Study on Efficient Simple Water Supply System in Rural Areas (농촌지역의 효율적인 간이 상수처리에 관한 연구)

  • 이홍근;백남원;백도현
    • Journal of Environmental Health Sciences
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    • v.22 no.3
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    • pp.103-115
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    • 1996
  • The purpose of this study was to establish acceptable criteria for the design of simple water treatment plant in rural areas. To develop efficient simple water treatment methods for rural areas, water quality in the study areas was investigated and rapid and slow filtrations in pilot-scale were tested under various conditions. The main results of this study are as follows. It was found that the water qualities of the study areas exceed the drinking water standards, which implies that some treatments are required in rural areas. Treatment efficiencies of both rapid sand and dual-media (sand and anthracite) filtration without pre-treatment such as flocculation and sedimentation are very low, which were turned out to be unadequate for the rural areas. Treatment efficiencies of both vertical and horizontal slow filtration without chlorination are very high for consumed $KMnO_4, NH_3-N, NO_3-N$, turbidity, and very low for coliform and bacteria. Treatment efficiencies of both vertical and horizontal slow filtration with chlorination are very high over the most pollutants. A slow filtration with chlorination is efficient for the rural areas. An adequate depth of sand layer is over 60 cm. A horizontal filtration is more economical than a vertical filtration. A horizontal filtration can be operated for a relatively long periods of time without sand washing or replacement because clogging is removed by simple back-washing.

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Establishment of a Simple and Rapid Gene Delivery System for Cucurbits by Using Engineered Zucchini Yellow Mosaic Virus

  • Kang, Minji;Seo, Jang Kyun;Choi, Hoseong;Choi, Hong Soo;Kim, Kook Hyung
    • The Plant Pathology Journal
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    • v.32 no.1
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    • pp.70-76
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    • 2016
  • The infectious full-length cDNA clone of zucchini yellow mosaic virus (ZYMV) isolate PA (pZYMV-PA), which was isolated from pumpkin, was constructed by utilizing viral transcription and processing signals to produce infectious in vivo transcripts. Simple rub-inoculation of plasmid DNAs of pZYMV-PA was successful to cause infection of zucchini plants (Cucurbita pepo L.). We further engineered this infectious cDNA clone of ZYMV as a viral vector for systemic expression of heterologous proteins in cucurbits. We successfully expressed two reporter genes including gfp and bar in zucchini plants by simple rub-inoculation of plasmid DNAs of the ZYMV-based expression constructs. Our method of the ZYMV-based viral vector in association with the simple rub-inoculation provides an easy and rapid approach for introduction and evaluation of heterologous genes in cucurbits.

Analysis of the simpleRTJ Class File Format (simpleRTJ 클래스 파일의 형식 분석)

  • 양희재
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.11a
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    • pp.373-377
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    • 2002
  • Unlike desktop systems, embedded systems usually meet a strict restriction on using memory. It is required to allocate several class files on memory to run a Java program. A Java class file contains such data including a constant pool, class overview, fields information, and methods information. Some of them are used merely for a debugging purpose, others for a program execution. This paper analyzes the internal structure, or format of the class files used for embedded Java systems. We also investigate how much memory will be necessary for each part of the class files when the files are allocated in memory. The experiment was performed on the simpleRTJ, an open-source commercial embedded Java system.

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