• Title/Summary/Keyword: Efficiency of operations

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The Relationship between Firms' Environmental, Social, Governance Factors and Their Financial Performance : An Empirical Rationale for Creating Shared Value (기업의 환경, 사회, 지배구조 요인과 재무성과의 관계 : 공유가치창출의 경험적 근거)

  • Min, Jae H.;Kim, Bumseok;Ha, Seungyin
    • Korean Management Science Review
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    • v.32 no.1
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    • pp.113-131
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    • 2015
  • We examine the relationship between firms' environmental (E), social (S), and governance (G) factors, with their financial performance in order to provide an empirical rationale for CSV (creating shared value) pursuing both of firms' profitability and CSR (corporate social responsibility). The financial performance is classified into four aspects such as profitability, stability, efficiency, and cash-flow, and each of these aspects is measured by two financial ratios respectively. To measure the firms' ESG performance, we employ the published performance grades by the Korea Corporate Governance Service for a three year span, from 2011 to 2013. Total of eight regression analyses are performed. The results show that firms' non-financial performance in general has statistically significant positive relationships with return on assets, return on net sales, and cash-flow from operating activities ratio, while it has negative relationships with net working capital ratio, asset turnover ratio, and cash-flow from investing activities ratio. It has no significant relationships with debt ratio and equity turnover ratio. The results imply that firms' non-financial performance may have a negative impact on some financial performance such as liquidity and efficiency in a short term, but it would eventually improve the firms' profitability and cash-generating ability, which provides an empirical evidence for the concept of CSV, and motivates the firms to participate in social contribution activities without sacrificing their profitability for their respective sustainablity management.

Energy-Efficient Operation Simulation of Factory HVAC System based on Machine Learning (머신러닝 기반 공장 HVAC 시스템의 에너지 효율화 운영 시뮬레이션)

  • Seok-Ju Lee;Van Quan Dao
    • Journal of Korea Society of Industrial Information Systems
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    • v.29 no.2
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    • pp.47-54
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    • 2024
  • The global decrease in traditional energy resources has prompted increasing energy demand, necessitating efforts to replace and optimize energy sources. This study focuses on enhancing energy efficiency in manufacturing plants, known for their high energy consumption. Through simulations and analyses, the study proposes a temperature-based control system for HVAC (Heating, Ventilating, and Air Conditioning) operations, utilizing machine learning algorithms to predict and optimize factory temperatures. The results indicate that this approach, particularly the prediction-based free cooling algorithm, can achieve over 10% energy savings compared to existing systems. This paper presents that implementing an efficient HVAC control system can significantly reduce overall factory energy consumption, with plans to apply it to real factories in the future.

Comparison of Blast Fragmentation Efficiencies from Conventional Bench and Double Air Deck Charge Blast Methods in Limestone Mine (석회석 광산에서 기존 일반발파와 이중분상 Air Deck 발파공법의 비교연구)

  • Kang, Dae-Woo;Hur, Won-Ho;Yang, Kook-Jung;Park, Dong-Chul
    • Explosives and Blasting
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    • v.29 no.2
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    • pp.13-31
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    • 2011
  • Air deck charge blast methods have been applied to improve the fragmentation in open cut bench blastings for mining developments. However, during large scale bench blasting operations, there exist some problems such as boulder productions due to explosive charge concentration. Especially, in case of lime stone mining, when air deck method is applied, there has been unintentionally concentrated on charging because the inside holes are often broken by erosion and decomposition. In this study, compared with general blasting, air deck blasting has been focused in lime stone mining. In other to maximize its efficiency, inside hole was examined by endoscope in advance and deck charge using air tube was applied to the section in which concentration might be taken place. Blasting efficiency, fragmentation, charging reduction rate, and total working hours (from charging to blasting) were the main object for comparing, and as a result, air deck was more efficient then the general blasting in all aspects except total working hours.

Color Media Instructions for Embedded Parallel Processors (임베디드 병렬 프로세서를 위한 칼라미디어 명령어 구현)

  • Kim, Cheol-Hong;Kim, Jong-Myon
    • Journal of KIISE:Computer Systems and Theory
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    • v.35 no.7
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    • pp.305-317
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    • 2008
  • As a mobile computing environment is rapidly changing, increasing user demand for multimedia-over-wireless capabilities on embedded processors places constraints on performance, power, and sire. In this regard, this paper proposes color media instructions (CMI) for single instruction, multiple data (SIMD) parallel processors to meet the computational requirements and cost goals. While existing multimedia extensions store and process 48-bit pixels in a 32-bit register, CMI, which considers that color components are perceptually less significant, supports parallel operations on two-packed compressed 16-bit YCbCr (6 bit Y and 5 bits Cb, Cr) data in a 32-bit datapath processor. This provides greater concurrency and efficiency for YCbCr data processing. Moreover, the ability to reduce data format size reduces system cost. The reduction in data bandwidth also simplifies system design. Experimental results on a representative SIMD parallel processor architecture show that CMI achieves an average speedup of 6.3x over the baseline SIMD parallel processor performance. This is in contrast to MMX (a representative Intel's multimedia extensions), which achieves an average speedup of only 3.7x over the same baseline SIMD architecture. CMI also outperforms MMX in both area efficiency (a 52% increase versus a 13% increase) and energy efficiency (a 50% increase versus an 11% increase). CMI improves the performance and efficiency with a mere 3% increase in the system area and a 5% increase in the system power, while MMX requires a 14% increase in the system area and a 16% increase in the system power.

Steady-State Analysis of ZVS and NON-ZVS Full-Bridge Inverters with Asymmetrical Control for Induction Heating Applications

  • Yachiangkam, Samart;Sangswang, Anawach;Naetiladdanon, Sumate;Koompai, Chayant;Chudjuarjeen, Saichol
    • Journal of Power Electronics
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    • v.15 no.2
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    • pp.544-554
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    • 2015
  • This paper presents a steady-state operation analysis of full-bridge series-resonant inverters focusing on the distorted load current due to low-quality-factor resonant circuits in induction heating and other applications. The regions of operation based on the zero-voltage switching (ZVS) and non-zero-voltage switching (NON-ZVS) operations of the asymmetrical voltage-cancellation control technique are identified. The effects of a distorted load current under a wide range of output powers are also analyzed for achieving a precise ZVS operating region. An experimental study is performed with a 1kW prototype. Simulation and experimental studies have confirmed the validity of the proposed method. An efficiency comparison between the variable frequency method and the conventional fixed-frequency method is provided.

Study on Effect of Shell Plate Deformation to Radar Cross Section of Warship (선체외판의 변형이 수상함 RCS에 미치는 영향 연구)

  • Kim, Kook-Hyun;Cho, Dae-Seung
    • Journal of the Society of Naval Architects of Korea
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    • v.48 no.6
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    • pp.509-515
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    • 2011
  • The radar cross section (RCS) of warships is a crucial design factor to improve the survivability in terms of not only low observablity of the platform but also efficiency of on-board sensors and jamming devices against enemy threat. In design stage, numerical models are generated in order to quantitatively assess RCS, of which hull surfaces are modeled with the finite number of the flat plate. However, in practice, hull surfaces are permanently deformed by various kinds of loads such as winds and ocean waves faced during operations. In this paper, the effect of these shell plate deformation to RCS is numerically investigated. For this purpose, RCS calculations are carried out for various kinds of numerical models, such as single plates, dihedrals, large-sized undulate plates, and virtual warships, with some extent of permanent deformation. The results are compared with those of corresponding models without permanent deformation. It is concluded that the permanent deformation of hull surface highly influences RCS characteristics of warships, therefore they should be considered in the RCS analysis.

Advanced Membrane Systems for Seawater Desalination. Kinetics of Salts Crystallization from RO Brines Promoted by Polymeric Membranes

  • Curcio, Efrem;Obaidani, Sulaiman Al;Macedonio, Francesca;Profio, Gianluca Di;Gualtieri, Silvia;Drioli, Enrico
    • Membrane Journal
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    • v.17 no.2
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    • pp.93-98
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    • 2007
  • The reliability of innovative membrane contactors technology (i.e. Gas/Liquid Membrane Contactors, Membrane Distillation/Crystallization) is today increasing for seawater desalination processes, where traditional pressure-driven membrane separation units are routinely operated. Furthermore, conventional membrane operations can be integrated with membrane contactors in order to promote possible improvements in process efficiency, operational stability, environmental impact, water quality and cost. Seawater is the most abundant aqueous solution on the earth: the amount of dissolved salts covers about 3% of its composition, and six elements (Na, Mg, Ca, K, Cl, S) account for more than 90% of ionic species. Recent investigations on Membrane Distillation-Crystallization have shown the possibility to achieve significant overall water recovery factors, to limit the brine disposal problem, and to recover valuable salts (i.e. calcium sulphate, sodium chloride, magnesium sulphate) by combining this technology with conventional RO trains. In this work, the kinetics of $CaSO_4{\cdot}2H_2O,\;NaCl\;and\;MgSO_4{\cdot}7H_2O$ crystallization is experimentally investigated in order to improve the design of the membrane-based crystallization unit.

On the Loading Plan of Container Ship (컨테이너선의 적재계량에 관한 연구)

  • 강기중;이철영
    • Journal of the Korean Institute of Navigation
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    • v.14 no.4
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    • pp.1-15
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    • 1990
  • With increasing ship's speed turnround and port time becomes a large percentage of total roundtrip time and this causes to accelerate the introduction of the various kind of modern handling equipment, the standardization of cargoes, and the improvement of the ship. However, it is still a drag on efficient operation of ship. Similarly, the turnround time at the container port is very important as a measure for the decision of the efficiency of port. To decrease operating coasts, the minimization of the time need to cargo handling at the ports of call must be achieved. Thus the optimization of the time need to cargo handling at the ports of call must be achieved. Thus the optimized Container Loading Plan is necessary, especially under the rapid speed of container operations. For the container loading plan, in this thesis, we use the hungarian method and the branch and bound method to get the initial disposition of both maximization of ship's GM and minimization of shift number to the obstructive container in a yard area. We apply the dynamic programming algorithm to get the final disposition for minimizing total turnroudn time and finally we analyzed the results to check whether the initial disposition is proper or not.

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Modal Analysis of Resonance and Stable Domain Calculation of Active Damping in Multi-inverter Grid-connected Systems

  • Wu, Jian;Chen, Tao;Han, Wanqin;Zhao, Jiaqi;Li, Binbin;Xu, Dianguo
    • Journal of Power Electronics
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    • v.18 no.1
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    • pp.185-194
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    • 2018
  • Interaction among multiple grid-connected inverters has a negative impact on the stable operations and power quality of a power grid. The interrelated influences of inverter inductor-capacitor-inductor filters constitute a high-order power network, and consequently, excite complex resonances at various frequencies. This study first establishes a micro-grid admittance matrix, in which inverters use deadbeat control. Multiple resonances can then be evaluated via modal analysis. For the active damping method applied to deadbeat control, the sampling frequency and the stable domain of the virtual damping ratio are also presented by analyzing system stability in the discrete domain. Simulation and experimental results confirm the efficiency of modal analysis and stable domain calculation in multi-inverter grid-connected systems.

A Study on the Railway Intelligent Transportation System, Developed Detailed Research Strategy (철도분야 지능형교통체계 세부추진전략 수립연구)

  • Lee, Jun;Jin, Il-Kyoung;Moon, Dae-Sub;Eom, Jin-Ki
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.614-620
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    • 2011
  • Railway intelligent transportation systems and related Ministry of Land and rail operating agency's railway informatization planning of information technology, effective through the use of management strategies to establish or run to support the systematic informatization investment that you want to execute work in progress, during and yet the institutional informatization of operations mainly in the form of efficiency is Chinhae. Accordingly, in order to promote the details of the final challenge of providing real-time information and the usefulness of this information collection is clearly for the railway sector by function of the components is necessary to distinguish. In this paper, the details of the plan goals, promoting convenient rail-based real-time information, to promote optimal gohyoeuleul railways, railway safety and comfort, was defined as three. Selection of each goal, because the direction of vision and ITS around the railroad center of road users by highlighting the benefits of the railroad's traffic information center user switching, real-time delivery of information diversity (enhanced content) that can increase the capacity of line train operating systems, enhancing the safety management system introduced in the monitoring system and is a railroad crossing. Because urban railway project in accordance with the goal of decreasing the annual rate of the train support, and the average passenger wait time savings, increased future demand for railway, rail safety, including securing the expected effects may occur.

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