• Journal of Korean Association for Spatial Structures
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• v.6 no.1 s.19
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• pp.65-73
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• 2006

In these days the floor vibration is beginning to make its appearance of the environmental dispute in dwelling building. Standard floor system are suggested for the settlement of this issue by government. The sound of floor impact sound is needed to secure comfortable quality in housing. Also, it is required an accurate analysis and a proper evaluation for floor vibration. Refine model is necessary for the floor system of housing to analyze accurately the floor vibration. But this refine model is not efficient because it is required so much running time for vibration analysis and it is difficult of modeling of standard floor slab. In this paper, new modeling methods of standard floor slab are proposed for the accurate rigidity evaluation. By using the new modeling method, the accurate vibration response can be obtained and can accurately evaluate the rigidity of standard floor system with resilient materials. Therefore the proposed modeling method is of practical use for vibration analysis of floor system of housing.

• Analytical Science and Technology
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• v.23 no.2
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• pp.109-118
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• 2010

Amended at the Law of indoor air quality management open a court according to the test method and excess standard of the fluid building material were changed. It used the paint and the putty in the fluid building material from this research and comparison of amended and original method it led and in about change direction of amended standard with change of the emission rate who is caused by in the amended test method and excess standard it examined. The reduction emission rate about 45% decreases in the change of test period of the paint, there was not an effect of the emission rate whom it follows in change of dry time. Also change of the emission rate whom it follows in change of application quantity the product which above $5\;mg/m^2h$ has the high emission rate the change of the emission rate is big but there was not change of the emission rate from the products of that others. The putty the emission rate about 61% decreases in case in the change of test period, there was not an effect of the emission rate whom it follows at dry time. The emission rate about 164% increased with increase of application quantity. It tried to compare two test methods, it compared in the paint and putty all current test method it was relaxed the possibility of knowing the thing there was a standard.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.2
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• pp.201-207
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• 2014

Objectives: Flow rate stability is very important for obtaining reliable measurements. However there is no easily used method for checking whether the flow rate set at the initial stage is sustained during sampling. The purpose of this study was to develop a method to evaluate the flow rate performance of gas sampling pumps with adsorbents commonly used to sample gases. Materials and methods: We tested the back pressure of gas sampling pumps commonly used in Korea with adsorbents such as charcoal and silica tubes and attempted to discover the combination conditions of adsorbents in accordance with back pressure required by ISO standard 13137. Results: We found the combination of sampling adsorbents to be applicable to the pressure drop required by the ISO standard for evaluating flow rate stability under increasing pressure drop and long term (eight-hour) performance. Conclusions: This evaluation method of using a sampling media matrix for checking flow rate stability as proposed by this study could be a highly useful tool for determining the reliability of the performance pumps before sampling.

• Korean Journal of Construction Engineering and Management
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• v.21 no.1
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• pp.21-31
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• 2020

Recently, interest and financial investment in community infrastructure have been growing. Accordingly, Korean Ministry of Land, Infrastructure and Transport suggested a standard for community infrastructure planning. The standard was based on time distance which represents citizens' accessibility to infrastructure facilities. This paper presents a method to use the navigation application programming interface (API) to calculate travel time. Buffer analysis using Euclidean distance has been widely used so far to evaluate accessibility. However, this method has limitation in that it does not reflect situations in the real world such as crosswalks and slope ways. The infrastructure accessibility indices of local towns in Yeonsu-gu, Incheon were computed based on the time obtained by navigation API. Also, Yeonsu-gu was spatially analyzed to reveal the resident units that are marginalized from community infrastructure facilities. Using navigation API enables to compute realistic accessibility indices and to find unbenefitted residential areas. The method presented in this paper can help community infrastructure planners for their facility spatial plan and budget distribution.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.12 no.4
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• pp.1-7
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• 2016

This paper presents a design method for the horizontal straight ground heat exchanger (GHE) based on the Kavanaugh design method. In order to examine suitability of the suggested design method, a horizontal line type GHE was installed in a steel box of which the size was $5m{\times}1m{\times}1m$ filled with dried Joomunjin standard, and a thermal response test (TRT) was conducted for 21 hours. A numerical analysis was performed for a simulation of a peak month operation and for its verification by finite element method (FEM). According to the simulation results, it was concluded that the suggested design method for a horizontal straight GHE is reliable for the estimation of a design length.

• Analytical Science and Technology
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• v.22 no.6
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• pp.439-448
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• 2009

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.4
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• pp.368-371
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• 2006

The standard procedure outlined by the United States Environmental Protection Agency (US EPA) in Method 1623 for analyzing Giardia lamblia cysts and Cryptosporidium parvum oocysts in water samples consists of filtration, elution, centrifugal concentration, immunomagnetic separation (IMS), and immunofluorescence assay (IFA) followed by microscopic examination. In this study, the extent of (oo)cyst loss in each step of this procedure was evaluated by comparing recovery yields in segmented analyses: (i) IMS + IFA, (ii) concentration + IMS + IFA, and (iii) filtration/elution + concentration + IMS + IFA. The complete (oo)cyst recovery by the full procedure was $52{\sim}57%$. The (oo) cyst loss in the IMS step was only $0{\sim}6%$, implying that IMS is a fairly reliable method for (oo)cyst purification. Centrifugal concentration of the eluted sample and pellet collection before IMS resulted in a loss of $8{\sim}14%$ of the (oo)cysts. The largest (oo)cyst loss occurred in the elution step, with $68{\sim}71%$ of the total loss. The permeated loss of (oo)cysts was negligible during filtration of the water sample with a $1.0-{\mu}m$ pore polyethersulfone (PES) capsule. These results demonstrated that the largest fraction of (oo)cyst loss in this procedure occurred due to poor elution from the filter matrix. Improvements in the elution methodology are therefore required to enhance the overall recovery yield and the reliability of the detection of these parasitic protozoa.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.7
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• pp.485-494
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• 2013

An efficient extraction method was developed for the analysis of 16 perfluorinated compounds (PFCs) in fish samples. We compared the recoveries from the Ion-Pairing Extraction (IPE), Liquid-Liquid Extraction (LLE), Solid-Phase Extraction (SPE), IPE + SPE method with varying the injection time of the internal standard. As a result, IPE method with the internal standard before extraction was evaluated as the most effective pretreatment method. The RPM (Revolution Per Munite) and pH in IPE-before method were additionally adjusted and the more efficient pretreatment method was established. The total 33 fish samples including liver and gut samples were collected from Korean markets and analyzed PFCs with developed pretreatment method of this study. Total 16 PFC levels in fish samples ranged from ND to 1.67 ng/g with 100% detection frequency. The average PFCs concentrations of muscle, liver and gut samples from fish were compared and showed the following trend: liver (17.8 ng/g) > gut (13.3 ng/g) > muscle (1.67 ng/g). The PFC levels in fish samples were similar or lower than other available previous results of foreign studies.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.811-815
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• 1998

Currently in Korea, standard operating procedure for the analyses of phenolic compounds in water is the spectrometric comparison of colors developed by 4-amino antipyrin with phenolic compounds. It is however that this method cannot identify individual compound and that some phenolic compounds do not react with 4-amino antipyrin. Spectrometric determinations of phenolic compounds were compared with chromatographic analyses of gas chromatography (GC) and high pressure liquid chromatography (HPLC) of various phenolic compounds. Individual phenolic compounds could be determined by both chromatographic methods but HPLC methods were more precise with lower detection levels in general.

• International Journal of Quality Innovation
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• v.5 no.2
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• pp.45-62
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• 2004

Any business activities may have impact on environment to a certain extent. Enterprises must find appropriate approaches to measure the impact on these environmental aspects, which can be used as the basis to direct enterprises' efforts to improve the environmental impact. The method used to evaluate significant factors in life cycle assessment standards is the one most commonly used by enterprises in general to measure environmental impact. By this method, the decisive factors of each environmental aspect are given scores according to the preset scoring standard of the organization. The scores are added up for each aspect and ranked to assess major environmental aspects. The drawback of this assessment method, that is, it ignores the degree to which each of these factors affects the environment, results in poor credibility. Therefore, this study attempts to solve some qualitative problems by applying to fuzzy theory, in particular, by identifying appropriate fuzzy numbers through fuzzy sets and membership function. Moreover, the study seeks to obtain a crisp value in the process of defuzzifization in order to make up for the shortfall of the original method in dealing with relative weight of decisive factors and thus increase its applicability and credibility. The department of light production of an electronics company is used as an example in this study to measure environmental aspects by employing both the traditional significant factor method and the fuzzy environmental impact assessment model proposed in this study. Based on verification and comparison of results, the model proposed in this study is more feasible as it reduces partiality in decision-making by taking the relative weights of decisive factors into consideration.