• KIEAE Journal
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• v.15 no.4
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• pp.69-76
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• 2015

Purpose: This study is to investigate the effects of facade insulation and window remodeling of an existing old middle school building on the reduction of energy consumption. Method: To analyze energy performance of building, using DesignBuilder v3.4, building energy simulation tool based EnergyPlus engine. Energy consumption and problem of target building was analyzed based on data and survey. Based on building energy simulations it analyzed the variation of energy demand for the building according to U-value of wall, glazing properties and external shading devices. Result: When insulation of building was reinforced, cooling and heating load was decreased. Glazing properties that minimize cooling and heating energy consumption were analyzed. In conclusion, it is important to choose SHGC and U-value of window fit in characteristic of target building. Setting external blind for cooling load decreases 5%.

• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.493-510
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• 2021

Mineral wool is an insulation material commonly used in passive fire protection (PFP) systems on offshore installations. Insulation materials have only been considered functional materials for thermal analysis in the conventional offshore PFP system design method. Hence, the structural performance of insulation has yet to be considered in the design of PFP systems. However, the structural elements of offshore PFP systems are often designed with excessive dimensions to satisfy structural requirements under external loads such as wind, fire and explosive pressure. To verify the structural contribution of insulation material, it was considered a structural material in this study. A series of material tensile tests was undertaken with two types of mineral wool at room temperature and at elevated temperatures for fire conditions. The mechanical properties were then verified with modified methods, and a database was constructed for application in a series of nonlinear structural and thermal finite-element analyses of an offshore bulkhead-type PFP system. Numerical analyses were performed with a conventional model without insulation and with a new suggested model with insulation. These analyses showed the structural contribution of the insulation in the structural behaviour of the PFP panel. The results suggest the need to consider the structural strength of the insulation material in PFP systems during the structural design step for offshore installations.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.293-300
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• 2014

This paper proposes a novel pattern recognition approach based on the radial basis function (RBF) neural network for identifying insulation defects of high-voltage electrical apparatus arising from partial discharge (PD). Pattern recognition of PD is used for identifying defects causing the PD, such as internal discharge, external discharge, corona, etc. This information is vital for estimating the harmfulness of the discharge in the insulation. Since an insulation defect, such as one resulting from PD, would have a corresponding particular pattern, pattern recognition of PD is significant means to discriminate insulation conditions of high-voltage electrical apparatus. To verify the proposed approach, experiments were conducted to demonstrate the field-test PD pattern recognition of cast resin current transformer (CRCT) models. These tests used artificial defects created in order to produce the common PD activities of CRCTs by using feature vectors of field-test PD patterns. The significant features are extracted by using nonlinear principal component analysis (NLPCA) method. The experimental data are found to be in close agreement with the recognized data. The test results show that the proposed approach is efficient and reliable.

• Fire Science and Engineering
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• v.32 no.4
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• pp.75-85
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• 2018

The Grenpell tower fire in England in June of 2016 is a representative example of damage caused by a vertical fire spreading through external insulation. Organic insulation materials, which are widely used in external insulation, have the disadvantage that they have good insulation performance but are vulnerable to fire. Aluminum composite panels are used as exterior wall finishing materials, and plastics used in aluminum are regarded as the cause of vertical fire spread. Due to the steel frame used to secure the aluminum composite panel to the outer wall, a cavity is formed between the outer wall and outer wall finish. When a fire occurs on the outer wall, the flammable outer wall as well as the flame generated from the heat-insulating material spreads vertically through the cavity, resulting in damage to people and property. In Korea, material unit performance tests are carried out by the Ministry of Land, Infrastructure and Transport notice 2015 - 744. However, in the UK, the BS 8414 test is used to measure the vertical fire spreading time on the outer wall in real scale fire tests. In this study, the risk of external wall fire was evaluated in an actual fire by conducting a real scale wall fire test (BS 8414), which was carried out in Europe, using aluminum composite panels of semi-noncombustible materials suitable for current domestic standards. The purpose of this study was to confirm the limitations of material unit evaluation of finishing materials and to confirm the necessity of introducing a system to prevent the spread of outer wall fire through an actual scale fire test.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.4
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• pp.287-292
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• 2017

A gas turbine is the main equipment used in a combined heat and power plant. It generates a high sound pressure noise level. To reduce the noise level, an enclosure is installed around the turbine. The sound insulation performance of the enclosure affects the amount of external noise reduction. In this study, a sound transmission loss analysis is performed using the boundary element method to predict sound insulation performance according to the numbers and shapes of the supporter. Radiated noise analysis is also performed for the main external points of the enclosure using ray-acoustics. The results of these analyses are presented and a design plan is proposed that reduces the sound pressure noise level of the enclosure.

• Korean Institute of Interior Design Journal
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• v.21 no.4
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• pp.114-120
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• 2012

There are lots of buildings which were built before the Legislation on building energy rating system. Remodeling of the buildings would be required for an improvement of the building energy rating system was enforced by the government. In the Passive Building Design, Elements which will be used for the remodeling are Insulation, Window, External venetian blind, Heat exchanger. The Purpose of this study is to indicate a Method for the improvement of Energy saving by an analysis of Construction Cost, Cost Evaluation, Energy performance Efficiency in applied design elements. In this study, the remodeling of existing public buildings to improve energy efficiency rating was applied to extract the elements of design-specific energy performance, efficiency, and the application of the designs that has been analyzed. The results were as follows: applying the design-specific cost-effective investment that represents the economy (investment efficiency/%) surveyed the average insulation(7.0%), triple glazed windows(10.1%), double glazed windows(12.1%), external shading(24.5%), and Heat(77.2%) were analyzed in order to be more efficient. Analysis of the basis of information on the existing public buildings to improve energy efficiency rating for the remodeling depending on driving conditions at a degree of individual difference. The main effect, however, depending on economic investment, design elements, heat exchangers, external awning, double glazed windows, triple glazed windows, insulation, is recommended as review of the order shall be determined.

• Archives of Plastic Surgery
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• v.32 no.6
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• pp.753-756
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• 2005

In the cases of severe arrythmia and conduction failure, a permanent implanted pacemaker is considered an essential treatment modality with less complication rate, broad indications and low morbidity. However, some pacemakers needs to be removed or replaced due to infection, in need of a lead upgrade, elective replacement, conduction failure or insulation failure. The most common indication for pacemaker extraction is infection. Conservative treatments such as administration of intravenous antibiotics and limitation of debridement are not effective and the removal of the entire pacing system is considered to be the best approach to pacemaker pocket infection. Although a locking stylet, a laser sheath and other newer methods of transvenous lead extraction have been proven to be effective, all leads cannot be removed. Moreover, major complications such as, cardiac tamponade and respiratory arrest during leads extraction procedure should not be ignored. We experienced two cases of exposed pacemakers in the subclavicular region. After removing the pacemaker body, exposed proximal lead was pulled out and cut off. The end of remnant external insulation tube was tied to prevent infection propagation between external insulation tube and inner metalic coil. Wounds were covered by local flap coverage. No other problems were detected during the one-year follow-up. Since there are few reports on lead-preserving method of treating limited infection of exposed pacemakers, we would like to present our new method for treating exposed pacemakers.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.2 no.3
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• pp.243-255
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• 1990

The objective of this study is to present an efficient measurement method of the effective thermal diffusivity for the fibrous insulation material. The non-linear parameter estimation (NPE) method is adapted for this analysis because of its accuracy and its results are compared with those by other direct methods such as CTP, CHP and STD method. A experimental system is constructed with bell-jar vaccum chamber, diffusion pump, tube type furnace, control unit and data acquisition system included with A/D converter and IBM XT/AT personal computer. The typical results obtained from this study are as follows; 1) NPE method can be recommended as an useful and accurate method to measure the effective thermal diffusivity of insuation material because it is shown that the measurement error compared with those by other direct methods is reduced for standard material, NBS-1450b. 2) NPE method can minimize the effects of ill-measured temperature due to external disturbance, because the final value is found by point to point estimating. 3) NPE method dose not depend on the kinds of heat flux, since the surfac temperature are used to estimate the thermal diffusivity. 4) With NPE method, compared with the steady state method, a measuring time and a sample size could be reduced.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.3
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• pp.44-50
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• 2012

The noise reduction is important one of considerations in the process of a civil aircraft development program. External noise sources are classified into an air-born source and a structure-born source. Among these noise sources, the most affected noise source into a cabin is the air-born noise source from an engine or propeller. The external noise is transmitted into the cabin through the fuselage structure of airplane which are composed of an fuselage structure, an interior trim panel and an acoustic insulation layer between an fuselage structure and an interior trim panel. Therefore, appropriate fuselage structure and acoustic insulation layer is very important to reduce the internal noise level. In this paper, the vibro-acoustic coupled analysis of the cabin noise of the 80~90 seats regional turboprop aircraft is carried out to validate the acoustic analysis method using Direct BEM and FEM. The sound pressure level onto the fuselage skin is acquired by fan-source noise analysis using BEM, and which sound pressure is used as acoustic noise source in vibro-acoustic noise analysis for cabin noise analysis using FEM.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.2
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• pp.27-33
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• 2012

In this paper, we researched the heat transfer analysis of 1.2[kW] BLDC motor on the condition of the external flow. The BLDC motor is fallen under influence of some heat generated by rotationg motor speed and it changes the life and confidence of motor. The heat makes to reduce the life of insulation and the magnetization. So motor can't make own performance. Therefore we calculated the losses about number of revolutions of motor. And then, we analyzed the heat transfer of BLDC motor by using the results when a fan attached to motor makes the external flow or not. The results showed that the temperature of motor increased constant values irrespective of external air temperature. The temperature of motor decreased very lower values than prior researches when the fan makes the external flow. In this method we can analyze the performance, losses and heat transfer of motor applied in the many industries.