• Journal of Animal Environmental Science
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• v.16 no.2
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• pp.99-108
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• 2010

The principal objective of this study was to investigate the cooling effects of geothermal heat pump system (GHPS) in farrowing house. A total of 96 sows were allocated to 2 pig housings (GHPS and conventional housing) with 48 for four weeks in summer season. During the experimental period of four weeks, the highest outside temperature observed was approximately $34.1^{\circ}C$, GHPS decrease indoor temperature of pig housing up to $30.9^{\circ}C$, but conventional pig housing was similar to outside temperature. Dust concentrations (maximum 61.4%) of particulate matter less than $10{\mu}m$ (PM 10) in GHPS-housing were lower than the conventional housing. GHPS showed no signigicant difference in carbon dioxide emission, whereas the ammonia gas concentration was significantly decreased in GHPS-housing compared to that of conventional housing. Sows in GHPS-housing showed significantly lower respiratory rate than those of the control group. GHPS did not affect hormone level, litter size and birth weight, but weaning weight of piglets was influenced by GHPS. Feed consumption of sows was significantly increased in GHPS-housing compared to the conventional hosing. These results suggest that GHPS decrease dust concentration, ammonia gas emission and indoor temperature of pig housing and may affect performance in sows and weaned piglets.

• Journal of the Korea Concrete Institute
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• v.28 no.2
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• pp.187-196
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• 2016

The current seismic design code prescribes that coupling beam should be reinforced using diagonally bundled bars. However, the use of a diagonally bundled bars has a negative effect on constructability and economic efficiency. In the present study, the seismic performance of 4 coupling beams with the different details of reinforcement was evaluated through a cyclic reversal loading test. The specimens were constructed to measure the results of the experimental variable regarding the details of shear reinforcement. Next, the seismic performance of the coupled shear wall system evaluated by methods proposed in the FEMA P695. The cyclic reversal loading test results of this study showed that the performance of coupling beams with relaxed reinforcement detail was almost similar to that of a coupling beam with the ACI detail and meet the level which requested from standard. The result of the seismic evaluation showed that all coupling beams are satisfied with the design code and seismic performance.

• Journal of IKEEE
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• v.24 no.3
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• pp.766-776
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• 2020

Recently, as interest in machine learning (ML) has increased and research using ML has become active, it is becoming more important to find an optimal hyperparameter combination for various ML models. In this paper, among various hyperparameters, we focused on ML optimizers, and measured and compared the performance of major optimizers using various datasets. In particular, we compared the performance of nine optimizers ranging from SGD, which is the most basic, to Momentum, NAG, AdaGrad, RMSProp, AdaDelta, Adam, AdaMax, and Nadam, using the MNIST, CIFAR-10, IRIS, TITANIC, and Boston Housing Price datasets. Experimental results showed that when Adam or Nadam was used, the loss of various ML models decreased most rapidly and their F1 score was also increased. Meanwhile, AdaMax showed a lot of instability during training and AdaDelta showed slower convergence speed and lower performance than other optimizers.

• Land and Housing Review
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• v.4 no.4
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• pp.407-415
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• 2013

Although many certification works have been carried out since Green Building Certification was enforced in 2002, analyses of the effects and efforts to improve this system are still poor. In the certification system, the energy performance was usually assessed by Energy Performance Index(EPI) of the Energy Saving Design Standards for Buildings. However, due to the inadequacy of analyses on current situation of the Index, there are difficulties to reform it. In this research of green-certified apartments, the author examined correlations between energy performance indexes and aimed to improve the Index by analyzing the scores based on point distribution of respective fields. The average EPI score of green-certified apartments was 74.68, and there was wide variations in min 63.4 and max 90. Furthermore, the average score of energy consumption, which was allotted the most points, was 7.04 out of 12. Therefore, betterments in the Index such as reinforcement in grade ranges and adjustment of the calculation method are necessary.

• Land and Housing Review
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• v.11 no.1
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• pp.87-94
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• 2020

To implement the planning of zero-energy buildings, their energy performance must be improved, and renewable energy applications must also be included. To accelerate the use of renewable energies in such buildings, BIPVs should be actively used in windows and on roofs. Window-type BIPVs are being developed in various forms depending on the size, composition, area ratio of the window, specification of glass, and so on. To analyze the applicability of various solar cells as window-type BIPVs, in this study, we evaluated their applicability, at the current development level, by analyzing the indoor illuminance, heat gain and heat loss; the cooling, heating, and lighting energy levels; and the generation performance of the various solar cells. To enhance the future applicability of window type BIPV, we analyze the overall energy performance of the building, according to changes in visible light transmittance and generation efficiency. The main research results are as follows. The area ratios above the standard illuminance, based on the window type and according to the VLT, were in order of low-e glazing, a-Si window, DSSC window, and c-Si window. The heat gain of the semi-transparent solar cell winodw was remarkably low. The energy consumption of buildings was highest in the order of c-Si window, DSSC window, a-Si window, and clear low-e window. However, in the case of including the power generation performance of the solar cell, the energy consumption was found to be high in order of DSSC window, c-Si window, a-Si window, and clear low-e window. In the future, if a window-type BIPV is developed, we believe that improvement in power generation performance and improvement in visible light transmittance will be needed.

• Land and Housing Review
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• v.14 no.2
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• pp.109-124
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• 2023

The purpose of this study was to implement a mobile application to evaluate the residential performance of Hanoks anytime and anyplace free of time and space constraints made possible by mobile devices such as smart phones. To effectively evaluate the performance of Hanoks, the mobile application includes architectural information and help functions to ease the usability by the general public. In addition, it is designed to be intuitively understood through the presentation of field photos through empirical cases in line with the functional characteristics of smart phones. To test the functionality of the mobile application, a field evaluation was conducted at the Set-yi-seo Literature Center in Eunpyeong Hanok Village. The findings of this study provide a basis for using smart phone based applications for evaluating buildings such as Hanoks in the future. It can be used as a model for developing future user-friendly performance evaluation applications for public Hanok research and development.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2004.11a
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• pp.367-371
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• 2004

The purpose of this research is furnishing of basic material for acoustic planning hereafter, after understanding the acoustic merits and demerits through measuring and analyzing on room acoustic of small performance hall. As the result of the measurement, those physical evaluation indexes such as SPL, RT, EDT, $D_{50}$, $C_{80}$, RASTI have being kept the satisfiable acoustic condition for the service of performance hall. Therefore, as small performance hall is regarded as equipped with sufficient volume of sound, reverberatory feeling and diffusive feeling, it judges as an excellent performance place, also it is considered that it could be utilized as a useful material when design so similar performance hall, hereafter.

• Land and Housing Review
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• v.5 no.4
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• pp.315-323
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• 2014

In this study, thermal transmittance which is a parameter to measure the thermal performance was evaluated for an internal insulation versus an external insulation. Then the ISO regulation was applied to evaluate it, and the superiority of an external insulation was verified by the thermal transmittance values. The three zones of apartment housing were selected to evaluate the performance. (1) The junction of an outer wall and a protruded slab : If there is no a thermal bridge protection system, then the values are about same in the two insulation systems, so the protection system should certainly be installed. If it is installed, then the value for the external insulation is 2 times lower than internal system. (2) The junction of a side wall and a flat slab: The value is 0.509W/mK for the internal insulation and about zero for the external insulation. (3) The junction of an outer wall and a division wall: The value is 0.451W/mK for the internal insulation and also about zero for the external insulation. A domestic regulation that could evaluate a thermal transmittance has to be established by applying the ISO regulation for the evaluation of external insulation systems in apartment housing in the future. Additionally, the government must decide which length should be used for the national standard.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.226-229
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• 2001

Recently the impact sound insulation performance is regarded as one of the most import factors in determining the quality of housing environment. In order to reduce the impact sound level transmitted through the floors and structures, establishing the standard level of impact sound insulation performance is needed. In this consideration, The effecting facts for the standard insulation level is reviewed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.368.2-368
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• 2002

It is increasing the interest on the comfortable dwelling environment, while sound insulation performance of materials and elements used in building is falling down as they become thicker and lighter Therefore, sound insulation performance in building has become the most important factor determining the level of housing, especially for apartment that has common wall and floor with next neighbors. (omitted)