• Title/Summary/Keyword: time use structure

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Use of Terminal Restriction Length Polymorphism (T-RFLP) Analysis to Evaluate Uncultivable Microbial Community Structure of Soil

  • Chauhan, Puneet Singh;Shagol, Charlotte C.;Yim, Woo-Jong;Tipayno, Sherlyn C.;Kim, Chang-Gi;Sa, Tong-Min
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.1
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    • pp.127-145
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    • 2011
  • Various environmental ecosystems are valuable sources for microbial ecology studies, and their analyses using recently developed molecular ecological approaches have drawn significant attention within the scientific community. Changes in the microbial community structures due to various anthropogenic activities can be evaluated by various culture-independent methods e.g. ARISA, DGGE, SSCP, T-RFLP, clone library, pyrosequencing, etc. Direct amplification of total community DNA and amplification of most conserved region (16S rRNA) are common initial steps, followed by either fingerprinting or sequencing analysis. Fingerprinting methods are relatively quicker than sequencing analysis in evaluating the changes in the microbial community. Being an efficient, sensitive and time- and cost effective method, T-RFLP is regularly used by many researchers to access the microbial diversity. Among various fingerprinting methods T-RFLP became an important tool in studying the microbial community structure because of its sensitivity and reproducibility. In this present review, we will discuss the important developments in T-RFLP methodology to distinguish the total microbial diversity and community composition in the various ecosystems.

Relationship between Ownership Structures and Earnings Management Behavior in Vietnamese Commercial Banks

  • TRAN, Thinh Quoc;LY, Anh Hoang;NGUYEN, Dung Khanh Ngoc
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.9
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    • pp.401-407
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    • 2020
  • Earnings management behavior is the use of accounting procedures, through accounting policies, to intentionally purposeful control in the provision of information to users. The purpose of this paper is to examine the relationship between ownership structure factors and earnings management behavior of 30 Vietnamese commercial banks. The paper uses the ordinary least square method to examine this relationship and employs time series data of 15 years from 2005 to 2019. The study also uses agency theory an asymmetric information theory. The authors examined six independent variables related to the ownership structure and these variables are typical of Vietnamese commercial banks. The results of the study show that the foreign ownership ratio is an opposite effect, while the ownership concentration variable has a positive effect on earnings management behavior of Vietnamese commercial banks. Based on that, the article proposes a number of policy suggestions for the State bank of Vietnam and Board of directors of commercial banks as well as investors to identify and to limit the earnings management behaviors of Vietnamese commercial banks. This contributes to ensuring information transparency as well as improving the quality of accounting information of Vietnamese commercial banks in the coming years.

An Experimental Study on the Evaluation of Mechanical Properties of CFT Column by Unstressed Test and Stub Specimen (비재하 가열시험 및 Stub 시험체를 활용한 CFT기둥의 역학적 특성평가에 관한 실험적 연구)

  • Lee, Dae-Hee;Lee, Tae-Gyu;Lee, Eui-Bae;Kim, Young-Sun;Kim, Gyu-Yong;Kim, Moo-Han
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2008.05a
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    • pp.209-213
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    • 2008
  • Recently, it increases in use of CFT(Concrete filled steel tube, below CFT) because material and method are required to be diversification and High-Performance according to increase the super-high structure. But, CFT column lose bearing capacity under fire because steel tube is exposed to outside. As a result, structure is collapsed and then it cause much damage. In case of the Europe, Japan and America, they have studied the fire-resistance performance of CFT under fire for a long time. However, it would have hardly studied it in domestic because it is much difficulty about experiment machine and cost. So it is needed base on fire-resist performance of CFT under fire. Therefore, this study dynamic specificity of stub column which made tester of stub column based on facts of strength and mixing fiber evaluated used heating and load testing machine. As a result, it is willing to propose fundamental data for quick and accurate diagnosis of deteriorated concrete structure by fire damage with experiment according to the design high strength concrete.

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Crash Optimization of an Automobile Frontal Structure Using Equivalent Static Loads (등가정하중을 이용한 차량 전면구조물 충돌최적설계)

  • Lee, Youngmyung;Ahn, Jin-Seok;Park, Gyung-Jin
    • Transactions of the Korean Society of Automotive Engineers
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    • v.23 no.6
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    • pp.583-590
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    • 2015
  • Automobile crash optimization is nonlinear dynamic response structural optimization that uses highly nonlinear crash analysis in the time domain. The equivalent static loads (ESLs) method has been proposed to solve such problems. The ESLs are the static load sets generating the same displacement field as that of nonlinear dynamic analysis. Linear static response structural optimization is employed with the ESLs as multiple loading conditions. Nonlinear dynamic analysis and linear static structural optimization are repeated until the convergence criteria are satisfied. Nonlinear dynamic crash analysis for frontal analysis may not have boundary conditions, but boundary conditions are required in linear static response optimization. This study proposes a method to use the inertia relief method to overcome the mismatch. An optimization problem is formulated for the design of an automobile frontal structure and solved by the proposed method.

A Study on the Expressional Characteristic of Glass outer Skin in Contemporary Space Design - Focusing on the case after 2000 - (현대 공간디자인에 있어서 유리외피의 표현특성에 관한 연구 - 2000년 이후의 사례를 중심으로 -)

  • Kim, Eun-Jung;Hong, Kwan-Seon
    • Korean Institute of Interior Design Journal
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    • v.17 no.3
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    • pp.123-130
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    • 2008
  • This study is about the Characteristic of glass outer skin expressions in space designs of contemporary society, due to the rapid development of information and digital technology. These days, the glass outer skin show the various images and space expressions which symbolize the informations and the society. The contemporary space designers focus on the glass as the structure materials, and purposely use the glass to achieve the structure concept which satisfies the needs of contemporary society. Therefore, it is a valuable work to analyze the meaning of glass, which has been used for the structure. Throughout the work which has been experienced by glass outer skin, theoretical studies have been achieved and recently the 14 examples were chosen as the glass structures based on the experimental research and frequency featured in magazines after year 2000, which we have analyzed in detail. Glass outer skin reflect the phrases of time in modern society, and throughout the meaning of it, we could see that the glass outer skin serve the roles in informations, interface, imaginary modernization, and as a landmark position. Therefore, in this study, we can make a definition of glass outer skin expression based on the situations of modem times by analyzing the symbolic meaning of glass outer skin in contemporary space designs.

Seismic Reliability Analysis of Offshore Wind Turbine Jacket Structure Using Stress Limit State (응력한계상태를 이용한 해상풍력발전기 재킷구조물의 지진신뢰성해석)

  • Lee, Gee-Nam;Kim, Dong-Hyawn
    • Journal of Ocean Engineering and Technology
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    • v.30 no.4
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    • pp.260-267
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    • 2016
  • Considering the effect of dynamic response amplification, a reliability analysis of an offshore wind turbine support structure under an earthquake is presented. A reliability analysis based on the dynamic response requires a large amount of time when using not only a level 3 approach but also level 2 such as a first order reliability method (FORM). Moreover, if a limit state is defined by using the maximum stress at a structural joint where stress concentration occurs, a three-dimensional element should be used in the finite element analysis. This makes the computational load much heavier. To deal with this kind of problem, two techniques are suggested in this paper. One is the application of a quasi-static structural analysis that takes the dynamic amplification effect into account. The other is the use of a stress concentration factor to estimate the maximum local stress. The proposed reliability analysis is performed using a level 2 FORM and verified using a level 3 simulation approach.

Spectrally encapsulated OFDM: Vectorized structure with minimal complexity

  • Kim, Myungsup;Kwak, Do Young;Jung, Jiwon;Kim, Ki-Man
    • ETRI Journal
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    • v.43 no.4
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    • pp.660-673
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    • 2021
  • To efficiently use frequency resources, the next 6th generation mobile communication technology must solve the problem of out-of-band emission (OoBE) of cyclic prefix (CP) orthogonal frequency division multiplexing (OFDM), which is not solved in 5th generation technology. This study describes a new zero insertion technique to replace an existing filtering scheme to solve this internal problem in OFDM signals. In the development of the proposed scheme, a precoder with a two-dimensional structure is first designed by generating a two-dimensional mapper and using the specialty of each matrix. A spectral shaping technique based on zero insertion instead of a long filter is proposed, so it can be applied not only to long OFDM symbols, but also very short ones. The proposed method shows that the transmitted signal is completely blocked at the bandwidth boundaries of signals according to the current standards, and it is confirmed that the proposed scheme is ideal with respect to bit error rate (BER) performance because its BER is the same as that of CP-OFDM. In addition, the proposed scheme can transformed into a real time structure through vectorizing process with minimal complexity.

Beyond design basis seismic evaluation of underground liquid storage tanks in existing nuclear power plants using simple method

  • Wang, Shen
    • Nuclear Engineering and Technology
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    • v.54 no.6
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    • pp.2147-2155
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    • 2022
  • Nuclear safety-related underground liquid storage tanks, such as those used to store fuel for emergency diesel generators, are critical components for safety of hundreds of existing nuclear power plants (NPP) worldwide. Since most of those NPP will continue to operate for decades, a beyond design base (BDB) seismic screening of safety-related underground tanks in those NPP is beneficial and essential to public safety. The analytical methodology for buried tank subjected to seismic effect, including a BDB seismic evaluation, needs to consider both soil-structure and fluid-structure interaction effects. Comprehensive analysis of such a soil-structure-fluid system is costly and time consuming, often subjected to availability of state-of-art finite element tools. Simple, but practically and reasonably accurate techniques for seismic evaluation of underground liquid storage tanks have not been established. In this study, a mechanics based solution is proposed for the evaluation of a cylindrical underground liquid storage tank using hand calculation methods. For validation, a practical example of two underground diesel fuel tanks in an existing nuclear power plant is presented and application of the proposed method is confirmed by using published results of the computer-aided System for Analysis of Soil Structural Interaction (SASSI). The proposed approach provides an easy to use tool for BDB seismic assessment prior to making decision of applying more costly technique by owner of the nuclear facility.

The Evolution and Structural Characteristics of Scaffolding Constructions in Macao Area from Historical Documents and Visual Materials (문헌 및 도상(圖像) 사료를 통해 본 마카오 '붕식(棚式)' 건축의 연원(淵源)과 구조 형식)

  • Hong, Shu-ying;Han, Dong-Soo
    • Journal of architectural history
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    • v.32 no.1
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    • pp.7-20
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    • 2023
  • The construction method of scaffolding structures is different from Mortise and Tenon and bucket arch structure of traditional large woodwork. It forms an independent construction system-fixing nodes with knots, a large number of diagonal braces are used to fix shelves and the structures mostly contain X-shape and triangular shape details. Simple ones include stalls, sheds, rain sheds, altars, lamp racks etc. But the scaffolding with larger scale and more complicated structure are modeled on archways, theatres and other buildings which are used in commercial and festival activities. At present, Macao, Hong Kong, Guangdong, Sichuan, Shanxi and other places in China have retained the custom of using scaffolding structures in important festival activities, but their uses, techniques and building types are slightly different from place to place. Due to building and demolishing at any time, the construction and service cycle is short. As a result, there are almost no physical objects left. We can only deduce the use and technical characteristics of ancient scaffolding skills through the colorful building styles that have been preserved with folk activities in various parts of China, the craftsmanship handed down from generation to generation by the scaffolding guild and artisans, and the description of cultural and historical materials and the mutual corroboration of visual materials.

A Collision detection from division space for performance improvement of MMORPG game engine (MMORPG 게임엔진의 성능개선을 위한 분할공간에서의 충돌검출)

  • Lee, Sung-Ug
    • The KIPS Transactions:PartB
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    • v.10B no.5
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    • pp.567-574
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    • 2003
  • Application field of third dimension graphic is becoming diversification by the fast development of hardware recently. Various theory of details technology necessary to design game such as 3D MMORPG (Massive Multi-play Online Role Flaying Game) that do with third dimension. Cyber city should be absorbed. It is the detection speed that this treatise is necessary in game engine design. 3D MMORPG game engine has much factor that influence to speed as well as rendering processing because it express huge third dimension city´s grate many building and individual fast effectively by real time. This treatise nay get concept about the collision in 3D MMORPG and detection speed elevation of game engine through improved detection method. Space division is need to process fast dynamically wide outside that is 3D MMORPG´s main detection target. 3D is constructed with tree construct individual that need collision using processing geometry dataset that is given through new graph. We may search individual that need in collision detection and improve the collision detection speed as using hierarchical bounding box that use it with detection volume. Octree that will use by division octree is used mainly to express rightly static object but this paper use limited OSP by limited space division structure to use this in dynamic environment. Limited OSP space use limited space with method that divide square to classify typically complicated 3D space´s object. Through this detection, this paper propose follow contents, first, this detection may judge collision detection at early time without doing all polygon´s collision examination. Second, this paper may improve detection efficiency of game engine through and then reduce detection time because detection time of bounding box´s collision detection.