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Corporation's Adaptation to Climate Change Related Natural Disasters : Embedding Resiliency in Supply Chain - A Study on Climate Change Related Natural Disaster Adaptation for Corporations -

  • Pak, Myong Sop;Kim, In Sun
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.64
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    • pp.239-264
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    • 2014
  • Two types of responses to climate change exist. First is climate mitigation which includes efforts of reducing CO2 and GHG emissions. Second response is climate adaptation process which is establishing climate resilience in the supply chain. The two are inherently different since mitigation strategy focus on eliminating the source of climate change and is long term in nature but adaptation strategy is moderating the impact of potential or current climate change. In order to embed climate resilience in the supply chain, mitigation strategies and adaption strategies must be implemented simultaneously. Corporation's adaptation to climate change related natural disaster can be seen as a response that includes mitigation and adaptation strategies simultaneously. A comprehensive climate change resilience supply chain approach has to be developed. This paper illustrated guidelines and adaptation process framework businesses can utilize in order to build climate resilience. Screening process before the actual assessment of risk was introduced as well as the whole adaptation process of establishing information system and strengthening climate-related operational flexibility.

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A Study on the Concentration Characteristics of Atmospheric Polycyclic Aromatic Hydrocarbons (PAHs) in Chongju

  • Lee, Hak-Sung;Kang, Byung-Wook;Kwon, Dong-Hyuk;Yeo, Hyun-Gu;Chun, Man-Young
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.E2
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    • pp.89-97
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    • 2003
  • Ambient polycyclic aromatic hydrocarbons (PAHs) were measured during the winter and summer of 2002 in Chongju. A filter pack and polyurethane foam (PUF) system was employed to collect simultaneously the particulate and gas phase PAHs. The samples were then analyzed using a gas chromatograph equipped with mass spectrometer detectors (GC/MSD). A total of 29 samples were collected and 11 PAH species were identified. The lower molecular weight PAH compounds (3∼4 rings) dominated the total PAH mass. The higher molecular weight PAH compounds (5∼6 rings) were less abundant. The PAHs were showed to exhibit seasonal variations. The concentrations of all com-pounds were significantly higher in winter than summer. The lower molecular weight PAHs were mostly found in the gas phase whereas the heavier ones were mainly associated with particulate phase. Vehicle emissions are likely to be the primary contributor of PAHs in Chongju. This study also demonstrated that it is necessary to perform simultaneously particulate and gas phase measurements to determine the accurate concentrations of ambient PAHs.

A Study on Performance Improvement Measures of Pressurized Smoke Control Systems for Exit Passageways of High-Rise Buildings (고층건축물의 피난경로 가압제연시스템 성능개선대책에 관한 연구)

  • Son, Bong-Sae;Kim, Jin-Soo
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.21 no.12
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    • pp.703-714
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    • 2009
  • One of the biggest problems in smoke control systems for high-rise buildings is stack effect, but there are no recognized methods or measures to solve the problem of stack effect as yet. The stack effect can be overcome by forming the uprising current inside the stair hall properly, but there is a limit to the height in supplying into the stair hall the smoke control air volume to be supplied to a floor in case of escape from fire. The limit to the height can be extended by over-coming the stack effect by pressurizing the stair hall and the ancillary room simultaneously. It can also be anticipated that the stack effect can be overcome by connecting the air supply shaft to the stair hall at the top. As a result of computer simulations using a network type of tool, it is found that adequate performance can be achieved by pressurizing the stair hall only for a building of 190m or less, and up to 360m when pressurizing the stair hall and the ancillary room simultaneously. In all those cases, however, an overpressure venting damper is required which operates within a suitable range for venting the overpressure outside.

(Design of New Architecture for Simultaneously Computing Multiplication and Squaring over $GF(2^m)$ based on Cellular Automata) ($GF(2^m)$상에서 셀룰러 오토마타를 이용한 곱셈/제곱 동시 연산기 설계)

  • Gu, Gyo-Min;Ha, Gyeong-Ju;Kim, Hyeon-Seong;Yu, Gi-Yeong
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.39 no.3
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    • pp.211-219
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    • 2002
  • In this paper, a new architecture that can simultaneously process modular multiplication and squaring on GF(2$^{m}$ ) in m clock cycles by using the cellular automata is presented. This can be used efficiently for the design of the modular exponentiation on the finite field which is the basic computation in most public key crypto systems such as Diffie-Hellman key exchange, EIGamal, etc. Also, the cellular automata architecture is simple, regular, modular, cascadable and therefore, can be utilized efficiently for the implementation of VLSI.

Design of a Power and Area Efficient 1:4 Interpolation FIR Filter for W-CDMA Applications (W-CDMA 응용을 위한 전력과 면적에 효율적인 1:4 보간 저역통과 여파기 설계)

  • Ryoo, Keun-Jang;Chong, Jong-Wha
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.37 no.10
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    • pp.73-81
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    • 2000
  • This paper presents the design and simulation of a power and area efficient interpolation FIR filter with partitioned look up table (LUT) structure. Using the symmetry of the filters coefficients and the contents of the LUT, the area of the proposed filter is minimized. The two filters share the partitioned LUT and activate the LUT selectively to realize the low power operation. The proposed filter has been designed in a 5.0 Volts 0.6${\mu}m$ CMOS technology. Power consumption results have been obtained from Powermill simulations. Experimental results suggest that the proposed filter reduces both the power consumption by 28% and simultaneously the gate area by 5% simultaneously compared to the previously proposed filters.

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Time Synchronization Using Mutual Interference in Two FMCW Radars (두 대의 FMCW 레이다에서 레이다간 상호 간섭 신호를 이용한 시간동기화 방법)

  • Cho, Byung-Lae;Lee, Jung-Soo;Lee, Jong-Min;Sun, Sun-Gu
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.11
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    • pp.1323-1326
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    • 2012
  • In military applications, many radar systems are simultaneously operated at a close range. In particular, the frequency allocation must be executed for operating the homogeneous radar systems at the same time. As many radar systems are simultaneously operated with overlapping frequency bands, interference between systems inevitably occurs. Because interference can degrade radar performance, suppression of interference is a critical issue in radar systems. In this letter, we analyze the interference between two FMCW radars. In addition, time synchronization method between radars using mutual interference is proposed. Experiments are carried out to validate the proposed method. The results demonstrate that the proposed method is suitable for real radar systems.

A Method of Progress Management of Projects Based on Schedule for Small and Medium Enterprises (중소기업을 위한 일정 기반의 프로젝트 진도 관리 방안)

  • Oh, Joseph;Kim, Bo-Hyun;Baek, Jae-Yong;Jung, So-Young;Choi, Young-Jae
    • IE interfaces
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    • v.25 no.2
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    • pp.276-282
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    • 2012
  • Earned value management(EVM) based progress management was designed to systematically manage large or huge projects with budget based criteria. For this reason, existed methods of EVM based progress management have a practical difficulty to apply to small and medium enterprises(SMEs) not possessing enough human resource, time, and cost. In other words, SMEs have performed simultaneously many small-sized projects emphasizing more project delivery than project budget. This study focuses on the area of project management applying to many small-sized projects simultaneously conducted by SMEs. Thus, the method proposed in this study is to manage only the progress of projects after removing cost factor in order to reduce man powers required for allocating the budget of projects to their all activities in detail in the stage of project planning. This study reveals that SMEs are able to manage progress of many projects easily and intuitively using the proposed method.

Binary Power Control for Sum Rate Maximization of Full Duplex Transmission in Multicell Networks

  • Vo, Ta-Hoang;Hwang, Won-Joo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.583-585
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    • 2016
  • The recent advances in wireless networks area have led to new techniques, such as small cells or full-duplex (FD) transmission, have also been developed to further increase the network capacity. Particularly, full-duplex communication promises expected throughput gain by doubling the spectrum compared to half-duplex (HD) communication. Because this technique permits one set of frequencies to simultaneously transmit and receive signals. In this paper, we focus on the binary power control for the users and the base stations in full-duplex multiple cellulars wireless networks to obtain optimal sum-rate under the effect interference and noise. We investigate with a scenario in there one carrier is assigned to only one user in each cell and construct a model for this problem. In this work, we apply the binary power control by the its simplification in the implemented algorithm for both uplink and downlink simultaneously to maximize sum data rate of the system. At first, we realize the 2-cells case separately to check the optimal power allocation whether being binary. Then, we carry on with N-cells case in general through properties of binary power control.

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A Simulation-Based Study of FAST TCP Compared to SCTP: Towards Multihoming Implementation Using FAST TCP

  • Arshad, Mohammad Junaid;Saleem, Mohammad
    • Journal of Communications and Networks
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    • v.12 no.3
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    • pp.275-284
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    • 2010
  • The current multihome-aware protocols (like stream control transmission protocol (SCTP) or parallel TCP for concurrent multipath data transfer (CMT) are not designed for high-capacity and large-latency networks; they often have performance problems transferring large data files over shared long-distance wide area networks. It has been shown that SCTP-CMT is more sensitive to receive buffer (rbuf) constraints, and this rbuf-blocking problem causes considerable throughput loss when multiple paths are used simultaneously. In this research paper, we demonstrate the weakness of SCTP-CMT rbuf constraints, and we then identify that rbuf-blocking problem in SCTP multihoming is mostly due to its loss-based nature for detecting network congestion. We present a simulation-based performance comparison of FAST TCP versus SCTP in high-speed networks for solving a number of throughput issues. This work proposes an end-to-end transport layer protocol (i.e., FAST TCP multihoming as a reliable, delaybased, multihome-aware, and selective ACK-based transport protocol), which can transfer data between a multihomed source and destination hosts through multiple paths simultaneously. Through extensive ns-2 simulations, we show that FAST TCP multihoming achieves the desired goals under a variety of network conditions. The experimental results and survey presented in this research also provide an insight on design decisions for the future high-speed multihomed transport layer protocols.

Correlation of wind load combinations including torsion on medium-rise buildings

  • Keast, D.C.;Barbagallo, A.;Wood, G.S.
    • Wind and Structures
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    • v.15 no.5
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    • pp.423-439
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    • 2012
  • Three common medium- rise building forms were physically tested to study their overall wind induced structural response. Emphasis was placed on the torsional response and its correlation with other peak responses. A higher correlation was found between the peak responses than between the general fluctuating parts of the signals. This suggests a common mechanism causing the peak event, and that this mechanism is potentially different to the mechanism causing the general load fluctuations. The measurements show that about 80% of the peak overall torsion occur simultaneously with the peak overall along wind drag for some generic building shapes. However, the peak torsional response occurs simultaneously with only 30%-40% of the peak overall drag for the rectangular model. These results emphasise the importance of load combinations for building design, which are often neglected in the design of medium sized rigid buildings for which the along-wind drag is dominant. Current design wind loading standards from around the world were evaluated against the results to establish their adequacy for building design incorporating wind-induced torsion effects. Although torsion is frequently neglected, for some structural systems it may become more important.