• Title/Summary/Keyword: Environment-free

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Typological Analysis of the Flexibility Concept for Sustainable Housing (지속가능한 주거 개발을 위한 가변성 개념의 유형학적 분석)

  • Mo, Jeong-hyun;Lee, Yeun-sook
    • KIEAE Journal
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    • v.3 no.3
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    • pp.59-66
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    • 2003
  • From an sustainable perspective, one unique characteristic of Open Housing is its ability to individualize variable elements (infill) from the permanent elements (support) in accordance with the residents' needs. Such environment-friendly elements of Open Housing can contribute to increasing the life span of the building, reducing the scope of reconstruction, and minimizing the amount of disposed building materials during demolition. The purpose of this research is to analyze the flexibility concept from a typological perspective, so that the concept of open housing can be better understood and its development can be promoted. The main method of this study was content analysis. Based on literature review of flexibility concept in a typological approach, a primary categories were established to describe the flexibility concept such as time for flexibility, scope, and the degree of openness. Subsequently each criterion was elaborated as follows: planning, supply, and utility in the time stage; internal and external flexibility in its scope; and fixed, semi-free, and free flexibility in its openness degree. This research exposes the lack of comprehensive knowledge of Open Housing caused by rather uniform features of previous studies. This research establishes and promotes a systematic approach for a more holistic meaning of Open Housing. This approach should contribute to the proper utilization and further development of sustainable housing.

Characteristics of Polymer irradiated by Low energy Ion Beam

  • sung Han;Yoon, Ki-Hyun;Jung, Hyung-Jin;Koh, Seok-Keun
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.109-109
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    • 1999
  • Recently, low energy ion beam irradiation has been adopted for surface modification. Low energy ion beam irradiation has many advantages in polymer engineering such as weak damage, good adhesion, noticeably-enhanced wettability(less than 15 degree), good reproducibility and so on. In this experiment, chemical reactions between free radicals and environment gas species have been investigated using angle-resolved XPS and TRIM code. In the case of low ion beam energy (around 1 keV), energy loss in polymer is mainly originated from atomic collisions instead of electronic interference. Atomic collisions could generated displaced atoms and free radicals. Cold cathode-ion source equipped with 5cm convex grid was used in an O2 environment. Base and working pressure were 5$\times$10-6 and 2.3$\times$10-4 Torr. Flow rates of argon and oxygen were fixed at 1.2 and 8 sccm. target materials are polyethylene polyvinyidenefluoride and polytetrafluoroethylene.

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Performance Analysis of Block Write Operation of File Systems on Linux Environment (리눅스 환경에서 파일 시스템들의 블록 쓰기 연산 성능 분석)

  • Choi, Jin-Oh
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.1
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    • pp.136-140
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    • 2015
  • Linux environment that is commonly used at embedded systems supports various file systems as Ext2, FAT, NTFS, etc. The file system that is equiped on the embedded system is mostly implemented on mini hard disk or flash memory. The types of the file system of the system make an effect on the performance of a application programs. The factors of file system performance on a same media are block read, block write and block free time. On these factors, block read and block free time are not so different according to the type of file systems. This paper evaluates the performance benchmark of file systems supported by linux about block allocation and write performance. The results obtained from various experiments shows the characteristics of each file system.

Nitritation of Anaerobic Digester Supernatant from Sludge Processing in MWTP (하수처리장 혐기성 소화조 상징액의 아질산화 반응 연구)

  • Gil, Kyung-Ik
    • Journal of Korean Society on Water Environment
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    • v.22 no.3
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    • pp.540-545
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    • 2006
  • The anaerobic digester supernatant (ADS) with high $NH_4-N$ concentration often results in a $NH_4-N$ overloading to the mainstream process of municipal wastewater treatment plant (MWTP). The nitrogen removal from the ADS is therefore important in order to achieve a stable mainstream process performance as well as to prevent $NH_4-N$ overloading due to ADS. Recently because of several advantages compared to the full nitrification, many works have shown interests in controlling the build-up of $NO_2-N$ in nitritation processes. The application of nitritation could save the aeration power compared to the full nitrification processes. In addition, the denitrification of $NO_2-N$ could reduce organic carbon requirements compared to the $NO_3-N$ denitrification. The purpose of this research was to find out the characteristics of the ADS nitritation and $NO_2-N$ accumulating factors from the laboratory reactor study. As a result based on the long-term laboratory experiment, it can be concluded that the degree of nitritation was closely related with the availability of alkalinity, free ammonia (FA), solid retention time (SRT) and solid concentration in the nitritation reactor.

Performance Analysis of Block Allocation of File Systems on Linux Environment (리눅스 환경에서 파일 시스템들의 블록 할당 성능 분석)

  • Choi, Jin-oh
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.05a
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    • pp.355-357
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    • 2014
  • Linux environment that is commonly used at embedded systems, supports various file systems as Ext2, FAT, NTFS, ets. The file system that is equiped on the embedded system is mostly implemented on mini hard disk or flash memory. The types of the file system of the system make an effect on the performance of a application programs. The factors of file system performance on a same media are block allocation and block free time. On these factors, block free time is not so different according to the type of file systems. This thesis performs the performance benchmark of a Ext2, FAT and NTFS file systems about block allocation performance. As the result, it is discussed that what file system is better at which case.

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Coupled evaluation of the free vibration characteristics of magneto-electro-elastic skew plates in hygrothermal environment

  • Mahesh, Vinyas;Kattimani, Subhaschandra;Harursampath, Dineshkumar;Trung, Nguyen-Thoi
    • Smart Structures and Systems
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    • v.24 no.2
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    • pp.267-292
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    • 2019
  • The present article addresses the coupled free vibration problem of skew magneto-electro-elastic plates (SMEE) considering the temperature-moisture dependent material properties. The plate kinematics follows Reddy's higher order shear deformation theory. With the aid of finite element methods, the governing equations of motion are derived considering the Hamilton's principle and solved by adopting condensation technique. The influence of different temperature and moisture dependent empirical constants on the frequency response of SMEE plate has been assessed. In addition, the natural frequencies corresponding to various fields are evaluated and the effect of empirical constants on these coupled frequencies is determined. A detailed parametric study has been carried out to assess the individual effects of temperature and moisture dependent empirical constants along with their combined effect, aspect ratio, length-to-width ratio, stacking sequence and boundary conditions. The results reveal that the external environment as well as the geometrical skewness has a significant influence on the stiffness of the SMEE plates.

Empirical Analysis of the Factors Affecting FTA Utilization by Exporting SMEs: Evidence from the South Korean Textile Industry

  • Song, Joon-heon
    • East Asian Economic Review
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    • v.26 no.3
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    • pp.227-253
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    • 2022
  • Despite the proliferation of free trade agreements (FTAs), many exporting firms are still confronted with several challenges in utilizing the FTA preferential tariffs. Based on the Technology-Organization-Environment (TOE) framework, this study empirically examines the factors affecting the utilization of FTA schemes by exporting firms. To clarify the key factors influencing FTA utilization, this study develops a conceptual model from the perspective of the adoption of information technology innovations. Eight factors derived from the TOE framework are proposed to explore the determinants of FTA utilization in export. Partial least squares structural equation modeling is employed to analyze the data collected from 162 exporting small- and medium-sized enterprises in the South Korean textile industry. The findings reveal that compatibility and trading partner influence are positively associated with FTA utilization, while complexity is negatively related. Factors of organizational context do not show any relationship with FTA utilization. This study is the first to theoretically analyze and empirically test the determinants of FTA utilization from the perspective of technological innovation adoptions. By examining the relative importance of TOE factors in the utilization of FTA schemes, this study expects to advance a holistic understanding on the perceived factors that could potentially affect the utilization of FTA schemes.

A Theoretical Approach: the Worker's task Stress and its Association with Job Performance

  • KIM, Ji-Hye
    • The Journal of Economics, Marketing and Management
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    • v.9 no.5
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    • pp.1-13
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    • 2021
  • Purpose: Purpose - This study investigates and aims to discuss regarding the employee's work stress and its relationship with employee's workability based on literature content analysis. Finally, this study will provide how employees can manage it and coexist while enjoying the benefits of a stress-free working environment. Research design, data, and methodology - The author collected many textual contexts from mostly peer-reviewed academic journals, which means that academic comprehensive integrity can be obtained by qualitative approach for this study with discussing and following a constructive review analysis. The content analysis aims to determine a textural dataset in the longtime frame from the newest textural information. Result - There is little doubt that this study was significant and relevant to the relationship between employee work stress and workability, indicating how organizations that manage their employees in a stress-free working environment. the present researcher separate the solutions into five categories according to the person or body responsible for the answers. Conclusion - The numerous solutions on how to deal with various stresses, the theoretical aspect of the solutions involving the theories developed by multiple past articles on how to solve work stress. In general, workability and work stress is a very large field of study. Another consideration is the numerous professionalisms in the world, and each has different ways stress is induced in the organization.

Vision and Lidar Sensor Fusion for VRU Classification and Tracking in the Urban Environment (카메라-라이다 센서 융합을 통한 VRU 분류 및 추적 알고리즘 개발)

  • Kim, Yujin;Lee, Hojun;Yi, Kyongsu
    • Journal of Auto-vehicle Safety Association
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    • v.13 no.4
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    • pp.7-13
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    • 2021
  • This paper presents an vulnerable road user (VRU) classification and tracking algorithm using vision and LiDAR sensor fusion method for urban autonomous driving. The classification and tracking for vulnerable road users such as pedestrian, bicycle, and motorcycle are essential for autonomous driving in complex urban environments. In this paper, a real-time object image detection algorithm called Yolo and object tracking algorithm from LiDAR point cloud are fused in the high level. The proposed algorithm consists of four parts. First, the object bounding boxes on the pixel coordinate, which is obtained from YOLO, are transformed into the local coordinate of subject vehicle using the homography matrix. Second, a LiDAR point cloud is clustered based on Euclidean distance and the clusters are associated using GNN. In addition, the states of clusters including position, heading angle, velocity and acceleration information are estimated using geometric model free approach (GMFA) in real-time. Finally, the each LiDAR track is matched with a vision track using angle information of transformed vision track and assigned a classification id. The proposed fusion algorithm is evaluated via real vehicle test in the urban environment.

Feasibility Study on the Two-dimensional Free Surface Simulation Using the Lattice-Boltzmann Method (Lattice Boltzmann Method를 이용한 2차원 자유수면 시뮬레이션 기법연구)

  • Jung, Rho-Taek
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.4
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    • pp.273-280
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    • 2012
  • The numerical simulation using the Lattice Boltzmann Method in the field of computational fluid dynamics becomes wider in the engineering applications because of its simplicity of update rules compared to the conventional Navier-Stokes solvers. Here, a two-dimensional D2Q9 LB model is numerically tested with a few new computational treatment on the free surface. The single relaxation time is applied under the gravitational field where applied only in the higher density fluid because of its big density difference. At the free surface, the reconstruction techniques in combination with boundary conditions is adopted in order to get some distribution function coming into the fluid site from the air one, and surface tension, early stable test for the gravitional field is considered in it. With the implementation of the gravitational profile, conserving the overall mass and grid dependency are observed during the calculations and freesurface advance track is well captured with an experiment.