• Title/Summary/Keyword: Energy wastage

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A study on the applicability of green energy in the Aids to Navigation (해양교통시설의 친환경 에너지 시스템 적용 가능성에 관한 연구)

  • Han, Chaang-Soo;Yoon, Jung-In;Park, Jung-Gun
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2009.06a
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    • pp.397-401
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    • 2009
  • On the crisis of international economy, the government is making an effort to seek economic growing motivation with the method of overcoming economic crisis and 'low carbon green growth'. Furthermore, to promote maritime vessel traffic service related inefficient energy wastage was revealed and eco-friendly alternative energy was accepted because of high price of oil in the beginning of 2008. In this situation, I'm going to discuss the possibility of eco-friendly energy system in maritime vessel traffic service with the way of cutting the budget and expansion of solar power generation system which was promoted to meet governmental 'energy saving plan for high price of oil'.

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Plugging and Re-opening Phenomena of the 5Cr-1Mo Steel Leak Hole by Water Leakage in Sodium Atmosphere (소듐 분위기에서 물누출에 의한 5Cr-1Mo Ferrite강 구멍의 막힘과 재개방 현상)

  • Jeong, Kyung-Chai;Kim, Tae-Joon;Choi, Jong-Hyeun;Park, Jin-Ho;Hwang, Sung-Tai
    • Applied Chemistry for Engineering
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    • v.9 no.5
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    • pp.674-679
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    • 1998
  • Small water leak experiment was carried out in liquid sodium atmosphere using a specimen of ferrite steel, which will be expected to be a material of the heat transfer tube of liquid metal fast breeder reactor. Self-plugging phenomena of leak path could be explained by the products of reaction and corrosion by sodium-water reaction. Also, re-opening mechanism of self-plugged path could be explained by the thermal transient and vibration of heat transfer tube. As a result, perfect re-opening time of self-plugged leak path was observed to be 129 minutes after water leak initiation. Re-opening shape of a specimen was appeared with double layer of circular type, and re-opening size of this specimen surface was about 2 mm diameter on sodium side.

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Corrosion Characteristics of a 5Cr-1Mo Steel Specimen by Sodium-Water Reaction (나트륨-물 반응에 의한 5Cr-1Mo Steel 시편의 부식특성)

  • Jeong, Kyung-Chai;Jeong, Ji-Yeong;Park, Jin-Ho;Hwang, Sung-Tai;Kim, Eui-Sik
    • Applied Chemistry for Engineering
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    • v.9 no.7
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    • pp.1023-1029
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    • 1998
  • Small water leak experiment was carried out for the 5Cr-1Mo steel specimen in sodium atmosphere. Perfect re-open time for the leak path of a specimen, by micro leak, was 129 minutes, and its size observed about 2 mm diameter at sodium side. The halos phenomena appeared around of leak spot before the leak path has re-opened, and the size of halos observed was different from the real re-open size of a specimen. Also, the corrosion of a specimen initiated from sodium side, but it did not occur at steam side. In AES analysis, the segregation phenomena of Cr in the specimen was found much more than those of other elements. And also, the sodium compounds formed by sodium-water reaction and deposited onto the leak site of specimen were observed by EPMA analysis and SEM photograph. It is postulated that the corrosion products could be precipitated to form mixed Na Fe Cr compounds.

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Pre-treatment of textile wastewaters containing Chrysophenine using hybrid membranes

  • lehi, Arash Yunessnia;Mousavirad, Seyed Jalaleddin;Akbari, Ahmad
    • Membrane and Water Treatment
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    • v.8 no.1
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    • pp.89-112
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    • 2017
  • Dyeing wastewaters are the most problematic wastewater in textile industries and also, growing amounts of waste fibers in carpet industries have concerned environmental specialists. Among different treatment methods, membrane filtration processes as energy-efficient and compatible way, were utilized for several individual problems. In this research, novel hybrid membranes were prepared by waste fibers of mechanical carpets as useful resource of membrane matrix and industrial graphite powder as filler to eliminate Chrysophenine GX from dyeing wastewater. These membranes were expected to be utilized for first stage of hybrid membrane filtration process including (adsorption-ultrafiltration) and nanofiltration in Kashan Textile Company. For scaling of membrane filtration process, fouling mechanism of these membranes were recognized and explained by the use of genetic algorithm, as well. The graphite increased rejection and diminished permeate flux at low concentration but in high concentration, the performance was significantly worsened. Among all hybrid membranes, 18% wt. waste fibers-1% wt. graphite membrane had the best performance and minimum fouling. The maximum pore size of this optimum membrane was ranged from 16.10 to 18.72 nm.

The relationship between carbon dioxide, crop and food production index in Ghana: By estimating the long-run elasticities and variance decomposition

  • Sarkodie, Samuel Asumadu;Owusu, Phebe Asantewaa
    • Environmental Engineering Research
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    • v.22 no.2
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    • pp.193-202
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    • 2017
  • The study estimated the relationship between carbon dioxide, crop and livestock production index in Ghana: Estimating the long-run elasticities and variance decomposition by employing a time series data spanning from 1960-2013 using both fit regression and ARDL models. There was evidence of a long-run equilibrium relationship between carbon dioxide emissions, crop production index and livestock production index. Evidence from the study shows that a 1% increase in crop production index will increase carbon dioxide emissions by 0.52%, while a 1% increase in livestock production index will increase carbon dioxide emissions by 0.81% in the long-run. There was evidence of a bidirectional causality between a crop production index and carbon dioxide emissions and a unidirectional causality exists from livestock production index to carbon dioxide emissions. Evidence from the variance decomposition shows that 37% of future fluctuations in carbon dioxide emissions are due to shocks in the crop production index while 18% of future fluctuations in carbon dioxide emissions are due to shocks in the livestock production index. Efforts towards reducing pre-production, production, transportation, processing and post-harvest losses are essential to reducing food wastage which affects Ghana's carbon footprint.

Assessment of Ultimate Longitudinal Strength of a VLCC considering Kinematic Displacement Theory (기하학적 변위 이론을 적용한 VLCC 최종종강도 평가)

  • Choung, Joonmo;Nam, Ji-Myung;Tayyar, Gokhan Tansel;Yoon, Sung-Won;Lee, Kangsu
    • Journal of the Society of Naval Architects of Korea
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    • v.50 no.4
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    • pp.255-261
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    • 2013
  • This paper presents prediction of ultimate longitudinal strength of a VLCC, "Energy Concentration" for which many benchmark studies have been carried out, based on kinematic displacement method proposed by Tayyar and Bayraktarkatal (2012). Kinematic displacement theory provides semi-analytical solution of average compressive strengths for various kinds of stiffened panels. The accuracy of average compressive strengths obtained from formulas of CSR(common structural rules) for tankers and kinematic displacement method are discussed in the fore part of this paper. Hull girder ultimate strengths using Smith method are also compared for different average compressive strengths. By comparing them with other benchmark results, it is concluded that the new method provides lower bounds, because hull girder strengths under the sagging and hogging moment conditions approach nearly lower bounds.

Global Corporate Citizenship: Cross-cultural Comparison of Best Practices in the Global Automotive Industry

  • Lee, Jung Wan;Tan, Wie Nie
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.1
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    • pp.261-271
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    • 2019
  • The study aims to investigate corporate social responsibility (CSR) best practices of the world automotive industry - Peugeot, BMW, Ford, Hyundai and Toyota among others - and recommend that they plan their business strategies and managerial responses accordingly. Based on the comparative research and case studies, this research finds that all five automobile manufacturers have taken very similar measures and actions in order to establish and maintain a high level of CSR practices. Sustainability was a core value in all five companies and served as a guiding principle in every aspect and approach of their business. This study finds that all five companies have CSR strategies in place to increase energy efficiency as well as reduce the usage and wastage of water in their production and plants. This research also finds that all companies monitor their suppliers and their own production process to ensure that they maintain their CSR standards. More impressively, this sustainable management practice is transferred along the companies' supply chain through education and training. Their suppliers and business partners are closely monitored to make sure that their high CSR standards are respected and followed. However, we find that there also are some differences in terms of their CSR deliveries and activities.

Assessment of heavy metals in sediments of Shitalakhya River, Bangladesh

  • Al-Razee, A.N.M.;Abser, Md. Nurul;Mottalib, Md. Abdul;Rahman, Md. Sayadur;Cho, Namjun
    • Analytical Science and Technology
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    • v.32 no.5
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    • pp.210-216
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    • 2019
  • Concentrations of Cu, Zn, Fe, Mn, Ni and Cr have been estimated in sediments of the Shitalakhya River at Polash-Ghorashal area, Narsingdi, Bangladesh. 36 samples of sediments from nine sampling point at different locations of Shitalakhya River were collected to determine the concentration of Cu, Zn, Fe, Mn, Ni, Cr and the samples were analyzed by atomic absorption spectrophotometer (AAS). The obtained results were compared with national and international guidelines. The levels of heavy metal concentrations in sediments were found to decrease in the order of Fe > Mn > Zn > Ni > Cu > Cr, respectively. The heavy metal concentration in sediment of Shitalakhya was below the recommended safe limits of heavy metals by WHO, FAO and other international standards. Contamination factor (CF) of Zn and Cu at sampling point Fsd2 show higher (> 1) values due to the influence of external discrete sources like wastage catalysts of ZnO and CuO. Geo-accumulation index values of the study indicate as non-contaminated to moderately contaminate.

Key Re-distribution Scheme of Dynamic Filtering Utilizing Attack Information for Improving Energy Efficiency in WSNs (무선 센서 네트워크에서 에너지 효율성 향상을 위해 공격정보를 활용한 동적 여과 기법의 키 재분배 기법)

  • Park, Dong-Jin;Cho, Tae-Ho
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.2
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    • pp.113-119
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    • 2016
  • Wireless sensor networks are vulnerable to an adversary due to scarce resources and wireless communication. An adversary can compromise a sensor node and launch a variety of attacks such as false report injection attacks. This attack may cause monetary damage resulting in energy drain by forwarding the false reports and false alarms at the base station. In order to address this problem, a number of en-route filtering schemes has been proposed. Notably, a dynamic en-route filtering scheme can save energy by filtering of the false report. In the key dissemination phase of the existing scheme, the nodes closer to the source node may not have matching keys to detect the false report. Therefore, continuous attacks may result in unnecessary energy wastage. In this paper, we propose a key re-distribution scheme to solve this issue. The proposed scheme early detects the false report injection attacks using initially assigned secret keys in the phase of the key pre-distribution. The experimental results demonstrate the validity of our scheme with energy efficiency of up to 26.63% and filtering capacity up to 15.92% as compared to the existing scheme.

Effects of the Duration of Liquid Feeding on Performance and Nutrient Digestibility in Weaned Pigs

  • Han, Yung-Keun;Thacker, P.A.;Yang, Joo-Sung
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.3
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    • pp.396-401
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    • 2006
  • A total of 72 castrated, crossbred ($Landrace{\times}Yorkshire$) piglets ($5.7{\pm}0.7kg$ BW) were allotted to one of three treatments including: a dry crumbled feed fed for 40 days; liquid feed provided for 10 days followed by dry crumbled feed for 30 days; and liquid feed provided for 20 days followed by dry crumbled feed for 20 days. Liquid feed was produced fresh each day by mixing water with dry crumbled feed at a ratio of 3:1. Pigs fed liquid feed for 10 days had a higher weight gain during the first 10 days (+16.8%; p = 0.01) and over the entire experimental period (+4.9%; p = 0.07) than pigs offered dry feed. Pigs fed liquid feed for 20 days also had a higher weight gain during the period from d 0 to 10 (+12.8%; p = 0.01), from d 10 to 20 (+8.5%; p = 0.06) and from d 0 to 20 (+9.7%; p = 0.01) than pigs offered dry feed. Pigs fed liquid feed for the first 10 days had higher feed intakes from d 0 to 10 (+22.6%; p = 0.01) and from d 0 to 40 (+5.3%; p = 0.02) than pigs offered dry feed. Pigs fed liquid feed for the first 20 days had a higher feed intake from d 0 to 10 (+21.8%; p = 0.01), from d 10 to 20 (+10.6%; p = 0.06), from d 0 to 20 (+14.6%; p = 0.01) and from d 0 to 40 (+6.6%; p = 0.02) than pigs offered dry feed. Feed conversion from d 0 to 40 tended to be poorer for pigs fed liquid feed during the first 20 days (p = 0.08) indicating an increase in feed wastage with liquid feeding. Nutrient digestibility at day 10 was unaffected by dietary treatment. However, at day 30, pigs fed liquid feed for 10 days had higher digestibility of dry matter (p = 0.08), energy (p = 0.10), crude protein (p = 0.03) and neutral detergent fibre (p = 0.05) than pigs fed liquid feed for 20 days. In conclusion, liquid feeding for 10 or 20 days increased the performance of weaned pigs during the specific time period that liquid feeding occurred but there were no carry over effects into subsequent production periods.