• Journal of the Korea Society of Computer and Information
• /
• v.16 no.4
• /
• pp.29-42
• /
• 2011

This study deals with the assessment indices about greening performance of datacenter. To do this, we survey existing standards and guidelines about datacenter. Those are used constructing new model of datacenter regarding greening performance. In this model, the relationship between major components will be represented by job-energy-thermal notation. Items, criteria and methods are created in order to complete the assessment indices. The existing assessment indices of the datacenter level and equipment level are investigated. Parameters, the degree of virtualization and energy efficiency also affects the performance of the green performance. Finally, to determine the improvements, the proposed indices is compared with the existing assessment tools.

• 월간 기계설비
• /
• s.282
• /
• pp.73-77
• /
• 2014

정부가 건축물의 에너지 성능을 20% 이상 끌어올리는 그린리모델링 사업 활성화를 목적으로 올해부터 공공건축물을 그린리모델링 할 경우 설계비와 시공비를 지원하는 등의 사업을 추진한다. 지난해 12월 30일 국토연구원 대강당에서 개최된 그린리모델링 사업설명회에 약 400여명이 참석하는 등 업계의 뜨거운 관심을 받고 있다. 국토교통부는 정부가 추진하는 그린리모델링 사업에 참여할 수 있는 사업자를 오는 1월 17까지 모집할 예정이다.

• 월간 기계설비
• /
• s.239
• /
• pp.24-25
• /
• 2010

국토해양부(장관 정종환)는 한국토지주택공사(LH)의 노후 영구임대주택 중 7개 단지, 8,808세대를 대상으로 지난 4월 23일부터 그린홈 시범사업(120억)에 들어갔다. 2025년까지 제로에너지 주택건설을 목표로 한 저탄소 녹색성장을 위한 그린홈 건설추진 사업의 일환으로 지난 해 10월 신규 공동주택(20세대 이상)에 대해 그린홈 건설을 의무화[("친환경 주택 건설기준 및 성능"('09.10월 국토해양부 고시)] 하는 건설기준이 마련되었다. 이에 따라 국토부는 기존주택의 그린홈화를 위해 금년부터 우선적으로 공공부문의 노후화된 영구임대주택을 그린홈 개선 시범사업으로 개보수 시행에 들어간다고 밝혔다.

• Applied Chemistry for Engineering
• /
• v.22 no.4
• /
• pp.367-375
• /
• 2011

Succinic acid ester derivatives have been used as additives for the base oil of metal working fluids and pressure working oils. In this paper, a series of succinic acid alkyl half-esters were synthesized with over 97% yields by ring-opening reaction of succinic anhydride and fatty alcohol and were soluble in 100 N base oil within 1 wt% concentration. The structures and purities of ester derivatives were confirmed by $^1H-NMR$ and FT-IR spectrum and GC analysis. Anti-corrosion properties of the esters in sea water were evaluated through ASTM D665 method and weight loss method and compared to that of succinic alkyl esters without carboxylic acid group in the molecule. As the results, anti-corrosion properties of succinic acid alkyl half-esters with carboxylic acid group were better than those of succinic acid alkyl esters without carboxylic acid group. And, Anti-corrosion properties of the esters with a shorter alkyl chain of high concentration showed better performance than those with longer alkyl chain of low concentration. Inhibition efficiency % (IE%) of the esters was over 95% in the concentration of 80 ppm and corrosion rate (CR) was below 0.3 mm/year at the same concentration. Thus, the corrosion properties of succinic acid alkyl half-esters result from the carboxylic acid groups in molecules.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.27 no.1
• /
• pp.78-85
• /
• 2023

This study evaluates the performance of reinforced concrete columns using hybrid fiber sheets for structural behavior. The purpose of this method is to improve the load-bearing capacity of the reinforced structure by impregnating a hybrid fiber sheet, which is woven by arranging aramid and glass fibers uniaxially and attached to an aged concrete structure requiring reinforcement with epoxy. In particular, not only the weight reduction of the material obtained by using a fiber lighter than the steel material, but also the low-strength, high-toughness fiber element among the fibers used delays the brittle fracture of the high-strength, low-toughness fiber element. The low-strength, high-toughness fiber element among the fibers used delays the brittle fracture of the high-strength, low-toughness fiber element, resulting in weight reduction compared to steel. The study conducted structural tests on four specimens, with the hybrid reinforcement method and failure mode as main variables. Specimen size and loading conditions were chosen to be comparable with previous studies. The structural performance of the specimen was evaluated using energy dissipation capacity and ductility. Analysis shows that excellent results can be obtained with the hybrid fiber sheet reinforcement.

• Applied Chemistry for Engineering
• /
• v.18 no.6
• /
• pp.599-602
• /
• 2007

23 F/cc grade new type of high density activated carbon from crystalline green cokes type of mesocarbon microbeads has been synthesized by chemical and electrochemical activation. In order for these materials to have high performance, electrochemical behavior during electrochemical activation has been investigated by sequential voltage applying schemes. These results showed that the effective voltage for electrochemical activation was about 2.7~3.2 V irrelevant to applying voltage due to the decrease of surface activation of activated carbon with high specific surface area.

• Proceedings of the Korean Information Science Society Conference
• /
• 2010.06b
• /
• pp.410-413
• /
• 2010

최근 그린 IT, 콜라우드 컴퓨팅 등이 새롭게 주목 받음에 따라 이들의 기반 기술인 가상화 기술이 더욱 활발히 연구되고 있다. 이에 따라 본 논문에서는 다양한 시스템을 손쉽게 운영할 수 있는 전가상화의 장점을 극대화하기 위해 새로운 동적 코드 변환기법에 대하여 제안한다. 이를 위해 동적 주소 변환 기법과 베이직 블록의 특성에 따라 동적 코드를 경량화하는 기법을 설계하였다. 기존의 동적 코드 변환 기법과의 성능 비교를 통해 제안한 기법의 안정성과 경량성를 확인할 수 있었다.

• Journal of the Korean Institute of Gas
• /
• v.25 no.6
• /
• pp.66-73
• /
• 2021

In this study, The full load test and WHTC mode test were performed to examine the effect on a heavy duty natural gas engine according to the type of standard gas for certification to check engine performance and exhaust characteristics. Two types of standard gas (G_r, G₂₃) and commercially available natural gas were applied as the fuel used. As a result of the test results of three natural gases with different fuel compositions, G₂₃ with a high nitrogen content was inferior in torque, fuel consumption, and thermal efficiency conditions. In addition, when evaluated in the WHTC mode it was possible to obtain a result that satisfies the EURO VI regulation. However, compared to the other two fuels, the emission characteristics of G₂₃ decreased CO2 and CO, but increased CH4, NOx and PN emissions.

• Korean Chemical Engineering Research
• /
• v.61 no.4
• /
• pp.576-583
• /
• 2023

This study aimed to investigate the impact of enhancing the electrode conductivity and mitigating the production of hydrogen peroxide - a by-product arising from lactate oxidation - on the performance of lactate electrodes. The electrical conductivity of the electrode was improved by modifying the surface of carbon paper with single-walled carbon nanotubes. Catalase was introduced to effectively eliminate the hydrogen peroxide produced during the lactate oxidation reaction. The carbon paper electrode, with simultaneous immobilization of both lactate oxidase and catalase, yielded a current 1.7 times greater than the electrode where only lactate oxidase was immobilized. The electrode in which lactate oxidase and catalase were co-immobilized on the surface of carbon paper modified with single-walled carbon nanotubes, produced a current of 171 µA, which was more than twice as much current as the carbon paper with only lactate oxidase immobilized. The optimized electrode showed a linear response up to lactate concentration of 20 mM, confirming that it can be used as a sensor electrode.

• Journal of Internet Computing and Services
• /
• v.15 no.3
• /
• pp.1-10
• /
• 2014

The cloud computing paradigm introduced pay-per-use models in which IT services can be created and scaled on-demand. However, service providers are still concerned about the constraints imposed by their physical infrastructures. In order to keep the required QoS and achieve the goal of upholding the SLA, virtualized resources must be efficiently consolidated to maximize system throughput while keeping energy consumption at a minimum. Using ANN, we propose a predictive SLA-aware approach for consolidating virtualized resources in a cloud environment. To maintain the QoS and to establish an optimal trade-off between performance and energy efficiency, the server's utilization threshold dynamically adapts to the physical machine's resource consumption. Furthermore, resource-intensive VMs are prevented from getting underprovisioned by assigning them to hosts that are both capable and reputable. To verify the performance of our proposed approach, we compare it with non-optimized conventional approaches as well as with other previously proposed techniques in a heterogeneous cloud environment setup.