• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.3
• /
• pp.1266-1273
• /
• 2013

The purpose of this study was to analysis the effect of form of outsole - complex function double rocker sole(CDR) vs. negative-heel rocker sole (NR) - on energy consumption and heart rate intensity during gait. 11 women, who had no medical history on musculoskeletal disease and surgery within 3 years prior to study, were participated. The walking energy cost per time (WECt) during 35minutes, heart rate intensity, and total calorie consumption were compared by using pair t-test. The WECt and total calorie consumption were found to be significantly higher(p<.05) in CDR than NR. However, there was no difference in HRi. Based on the present study, CDR shoe may have significant implications in shoe prescription for people who want to increase energy consumption.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.9 no.3
• /
• pp.410-425
• /
• 1997

Buildings are mostly under part load conditions causing an inefficient system operation in terms of energy consumption. It is critical to operate building air-conditioning system with a scientific or optimal manner which minimizes energy consumption and maintains thermal comfort by matching building sensible and latent loads. Little research has been performed in developing general methodologies for the optimal operation of air-conditioning system. Based on this research motivation, system simulation program was developed by adopting various equipment operating strategies which are energy efficient especially for humidity control in summer. A numerical optimization technique was utilized to search optimal solution for multi-independent variables and then linked to the developed system simulation model within a mam program. The main goal of the study is to provide a systematic framework and guideline for the optimal operation of air-conditioning system focusing on air-side. For given cooling loads and ambient outdoor conditions the optimal operating strategies of a commercial building are determined by minimizing a constrained objective function by a nonlinear programming technique. Desired space setpoint conditions were found through evaluating the trade-offs between comfort and system power consumption. The results show that supply airflow rate and compressor fraction play main roles in the optimization process. It was found that variable setpoint optimization technique could produce lower indoor humidity level demanding less power consumption which will be benefits for building applications of humidity problem.

• Korean System Dynamics Review
• /
• v.15 no.2
• /
• pp.51-74
• /
• 2014

Over the past few years Korea has achieved rapid economic growth, while the deepening polarization of income has negatively affected Korea economy and society. It can be the reason of this negative effect on economy that the increased income by the economic growth has not been distributed socially, but overly focused on one part of social class. One of the important and powerful solution of social polarization could be the strengthening of the income distribution. In these circumstances, the social interest and discussion on the universal welfare system and on the basic income as the means of income redistribution have been increasing. In this study, a system dynamic analysis was conducted to find how an universal cash payment as basic income providing cash benefits impacts on the promotion of consumption in private sector, of local jobs and of local economic organizations. Recently, the poor energy consumption ability of energy poverty became one of the social problems. Also it was analysed how an energy payment-in-kind as basic income influences on the energy consumption of the region, the energy production capacity, the promotion of local energy. The universal cash payment and energy payment-in-kind as the basic income policy showed similar and positive effects on the local economy system and on the local energy system respectively.

• Journal of the Architectural Institute of Korea Planning & Design
• /
• v.34 no.2
• /
• pp.41-48
• /
• 2018

This study is expected to provide some basic data on how to apply more economical and efficient eco-friendly factors to reduce the carbon emissions. It has been scrutinized and analyzed the environmental factors of passive eco-friendly elements along with active eco-friendly elements as more efficient factors for energy conservation based on the case of a newly constructed broadcasting building with the green building certification in Sangam-dong DMC area. The first analysis was the energy consumption trends in Korea and the necessity of energy saving. Secondly, it was examined the energy consumption in the current status of the broadcasting building. Thirdly, it was looked into the correlation between the eco-friendly design application factors applied to the broadcasting building and the energy consumption types. As a result of the analysis, the application of fan and feed pump inverter along with ventilation system of waste heat recovery ventilation system were more meaningful in accordance with the economic feasibility of broadcasting buildings rather than economical effect of passive elements such as rooftop garden, reinforcement of building insulation. Also, the application of lighting control had the economical feasibility. Therefore, when it is intended to change the green building certification energy related evaluation items of the similar broadcasting building types, it is necessary to change the direction of adding weight to the more economical active element items in the future.

• Journal of Communications and Networks
• /
• v.14 no.1
• /
• pp.75-90
• /
• 2012

Thin client computing trades local processing for network bandwidth consumption by offloading application logic to remote servers. User input and display updates are exchanged between client and server through a thin client protocol. On wireless devices, the thin client protocol traffic can lead to a significantly higher power consumption of the radio interface. In this article, a cross-layer framework is presented that transitions the wireless network interface card (WNIC) to the energy-conserving sleep mode when no traffic from the server is expected. The approach is validated for different wireless channel conditions, such as path loss and available bandwidth, as well as for different network roundtrip time values. Using this cross-layer algorithm for sample scenario with a remote text editor, and through experiments based on actual user traces, a reduction of the WNIC energy consumption of up to 36.82% is obtained, without degrading the application's reactivity.

• KIEAE Journal
• /
• v.12 no.3
• /
• pp.101-106
• /
• 2012

Lighting energy accounts for approximately 20% of the electrical energy used worldwide. Thus, High efficiency Light emitting diode(LED)lighting is getting more popular as the next generation lighting replaced to traditional lighting fixtures. Also, LED lighting not only has a long lifetime but also can realize a variety visual environments through the wavelengh control. The lighting energy varies depending on the Spectral Power Distribution(SPD) even though the Illuminance level is same. Therefore, This study indicates that the difference of indoor energy consumption under the same illuminance level when Spectral Power Distribution(SPD) is different. As a result, Lighting energy consumption under red-color emphasizing SPD is about 10% lower than under blue-color emphasizing SPDs.

• Journal of the Korean Society of Industry Convergence
• /
• v.25 no.6_3
• /
• pp.1135-1145
• /
• 2022

Due to increase in concerns related to the climate change, state-wide promotion of the carbon neutrality has been in progress thus far. Smart City could be one of the measures as the initiative to mitigate the missions process. The primary purpose of Smart City can be summarized to be maximization of the social net-beneift to be returned for the local citizens and derivation of the optimal pattern of the energy consumption could belong to one of the elements included in the net-benefit. Currently, the energy consumption by the buildings has been determined to be responsible for the greatest consumption among the sectors considered to be energy-intensive. Moreover, considering the fact that the consumption by operations of HVAC is responsible for nearly 40% in the commercial buildings, it is virtually not possible to optimize schedules for the energy consumption with considerable deliverables from the perspective of the urban planners. Thus, the methods to implement the optimal schedules for the HVAC commissioned with the OHUs were concluded to be the suitable candidate resources for the simulation by EnergyPlus capable of monitoring the thermal changes in each subject space in the present research.

• Journal of Korean Physical Therapy Science
• /
• v.15 no.1
• /
• pp.39-45
• /
• 2008

This study was undertaken to identify the influence which affect on gait speed and energy consumption regarding putting on arm sling during gait of the 40 hemiplegic patients selected from University Hospital and rehabilitation center in seoul during two months. The analysis of data was performed using the paired samples ttest to compare the differences of gait velocity, heart rate, oxygen consumption and oxygen cost in gait of preand post－ arm sling. The results of this study were as follows; 1. When comparing the result before putting on arm sling in the gait of hemiplegic patient, gait velocity after putting on arm sling was statistically significantly increased(p<.05). 2. When comparing the result before putting on arm sling in the gait of hemiplegic patient, heart rate after putting on arm sling was statistically significantly decreased(p<.05). 3. When comparing the result before putting on arm sling in the gait of hemiplegic patient, oxygen consumption per weight after putting on arm sling was statistically significantly decreased(p<.05). 4. When comparing the result before putting on arm sling in the gait of hemiplegic patient, oxygen consumption rate per weight after putting on arm sling was statistically significantly decreased(p<.05). When putting together the above result, the gait with arm sling in comparison with the gait without arm sling was to increase gait velocity, decrease heart rate, decrease oxygen consumption and was finally to decrease energy consumption in the gait of hemiplegic patient.

• KIPS Transactions on Software and Data Engineering
• /
• v.5 no.5
• /
• pp.209-220
• /
• 2016

While the services of mobile devices like smart phone, tablet, and smart watch have been increased and varied, the software embedded into such devices has been also increased in size and functional complexity. Therefore, increasing operation time of mobile devices for serviceability became an important issue due to the limitation of battery power. Recent studies focus on the software development having efficient behavioral patterns because the energy consumption of mobile devices is caused by software behaviors which control the hardware operations. However, it is often difficult to develop the embedded software with considering energy-efficiency and behavior optimization due to the short development cycle of the mobile services in many cases. Therefore, this paper proposes the refactoring techniques for reducing energy consumption, and enables to fulfill the energy requirements during software development and maintenance. We defined energy bad smells with the code patterns that can excessively consume the energy, and our refactoring techniques are to remove these bad smells. We performed some case studies to verify the usefulness of our refactoring techniques.

• Journal of Urban Science
• /
• v.11 no.1
• /
• pp.15-20
• /
• 2022

The issue of hotel energy use is growing more significant as the hotel industry expands. It is important to take into account the electrical installation and space-specific features in a room unit in order to comprehend the energy consumption of a hotel guestroom. In light of this, this study aimed to analyze standby power for enhancing the energy efficiency of a hotel guestroom during check-out status. This study was conducted in three steps: (i) data collection; (ii) analysis of energy consumption patterns; and (iii) analysis of energy efficiency improvement plan. The main findings of this study can be summarized as follows. First, 32.24% of energy was used in fan coil unit) during check-out status. Second, a hotel guestroom had a 4.30% energy saving potential, based on energy consumption patterns during check-out status. This study can contribute to support hotel management to operate guestrooms differently by helping them identify patterns in energy use and realize potential savings.