• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.30 no.3
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• pp.116-122
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• 2018

The purpose of this study was to confirm the effects of flush-out in the reduction of formaldehyde concentration in newly built residential buildings. The field measurements were conducted on two complexes of multi-residential buildings which are located in the suburban area of Seoul. About eight samples of residential buildings were selected to measure the changes in formaldehyde concentrations after flush-out from the two apartment complexes. The concentration of formaldehyde was measured using DNPH cartridge and HPLC. From the results of the field measurements, it was established that indoor formaldehyde concentration decreases 27.6~54.2% in the samples after flush-out. The number of days that the flush-out were conducted was noted to have no significant influence on the reduction rate of formaldehyde concentration when the flush-out continued more than 7 days. The comparison with Bake-out showed that flush-out also can reduce formaldehyde in newly built buildings as same levels of it.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.479-479
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• 2003

We investigated the tyrosinase inhibitory effect using whitening materials such as arbutin, ethyl ascorbyl ether, glabridin, kojic acid, magnesium ascorbyl phosphate and ascorbic acid. Tyrosinase inhibition rate were determined varying the enzyme concentration, reaction time, reaction temperature and pH. The optimal conditions to measure the inhibitory efficacy were as follows. : enzyme concentration 1,500 or 2,000IU/mL, reaction time 15min(for the enzyme concentration 1,500 IU/mL) and l0min(for the enzyme concentration 2,000IU/mL), reation temperature 42$^{\circ}C$, pH 6.5. Under these conditions $IC_{50}$/ of arbutin, ethyl ascorbyl ether, glabridin, kojic acid, magnesium ascorbyl phosphate and ascorbic acid were calculated. In the case of magnesium ascorbyl phosphate, the inhibitory effect of tyrosinase was very low and the $IC_{50}$/ of magnesium ascorbyl phosphate could not be calculated. Other five materials showed good inhibitory effect of tyrosinase and can be used for the whitening materials.

• Journal of Pharmacopuncture
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• v.24 no.3
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• pp.142-151
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• 2021

Objectives: Although Korean Medicine (KM) subsidized by the National Health Insurance (NHI) has been used for a long time, there has been no active analysis using claims data. Therefore, the purpose of this study was to examine the NHI KM utilization trend using NHI statistics and to measure the level of market concentration by year. Methods: By restructuring the contents of NHI Statistics for Pharmaceuticals for 2010-2019, the claim cases, costs, and annual growth rates of KM were demonstrated by year, sex, age group, region, therapeutic group, and KM treatment. The proportion of highly used k treatments in cost was calculated as the concentration ratio (CR) k and its trend by year was investigated. Results: In 2019, the NHI cost on KM amounted to ₩38.2 billion KRW, increasing by 11.6% per year on average in 2010-2019. Notably, KM was used more frequently among women and patients aged ≥ 65 years, and the mixed formulation accounted for 95% of the total cost of KM. The CR of the simple formulation increased rapidly, whereas that of the mixed formulation remained constant. In 2019, three simple formulation treatments- peony, licorice, and ginseng- accounted for 93.8% of the total cost for KM (CR3 = 93.8%). Conclusion: NHI KM is rapidly increasing. Investigating the CR of KM confirmed that KM prescriptions have been concentrated in small numbers over the past 10 years.

• Journal of Wellbeing Management and Applied Psychology
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• v.5 no.3
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• pp.19-25
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• 2022

Purpose: As interest in odor increases, odor complaints are also rapidly increasing. Traditional markets are not included in malodor control areas and are not easy to manage, so measure the odor substances generated in traditional markets and analyze the cause of high concentration points. Research design, data and methodology: The average value was presented by continuously measuring the combined odor, TVOC, hydrogen sulfide, and ammonia for 5 minutes at 100m intervals in Joong-ang traditional market, Jayu traditional market, Doraemi traditional market, and Sundae Alley in Wonju, Gangwon-do. In each market, up to the third highest concentration point for each measurement item was marked and analyzed. Results: The Joong-ang traditional market, Doraemi traditional market, and Sundae Alley had high readings at the intersection. The Jayu traditional market had high measurements around restaurants and clothing stores. In addition, the concentration of complex malodors was also high at the points where the hydrogen sulfide concentration was measured. Conclusions: Odor generated in traditional markets is an important indicator for merchants and consumers. Therefore, in future studies, analysis that can supplement the limitations of measurement data and seasonal effects is needed.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.66-72
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• 2024

Determining the nutrient stoichiometry in plant organs is critical for understanding nutrient uptake and cycling in forest ecosystems. This study evaluated nutrient concentrations and stoichiometry in various plant organs (stem, bark, branches, and foliage) of species found in four warm-temperate forests in southern Korea. Cryptomeria japonica D. Don (CJ), Quercus serrata Thunb. (QS), evergreen broadleaved tree species (EB), and bamboo spp. (BB) were destructively sampled to measure nutrient (C, N, and P) concentrations in the plant organs. The mean C concentration in the stem was significantly higher in CJ than in QS, BB, or EB, whereas the C concentration in the foliage was the lowest in BB. The mean foliar N and P concentrations were higher in BB than in EB or CJ. The mean stem C:N and C:P ratios were highest in CJ but were lowest in the foliage of BB. Overall, stems of all species showed a strong positive correlation between C concentration and dry weight, but a negative correlation between N and dry weight. The N and P concentrations of foliage and bark were strongly correlated, whereas those of the stem and branches were poorly correlated. Positive correlations were detected between the C:N and C:P ratios in bark and foliage. These results indicate the existence of intraspecific differences in nutrient requirements in warm-temperate forest species and add to the understanding of nutrient uptake and storage patterns in the organs of species growing in warm-temperate forests.

• International journal of advanced smart convergence
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• v.5 no.2
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• pp.73-79
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• 2016

Remote sensing and measurement are of paramount importance of providing information on the state of water quality in water bodies. The formation and growth of cyanobacteria is of serious concern to in land aquatic life forms and human life. The main cause of water quality deterioration stems from anthropogenic induced eutrophication. The goal of this research to quantify and determine the spatial distribution of cyanobacteria concentration in the water using remote sensing technique. The standard approach to measure water quality based on the direct measurement of the fluorescence of the chlorophyll a in the living algal cells and the same approach used to detect the phycobilin pigments found in blue-green algae (a.k.a. cyanobacteria), phycocyanin and phycoerythrin. This paper propose the emerging sensor design to measure the water quality based on the optical analysis by fluorescence of the phycocyanin pigment. In this research, we developed an method to sense and quantify to derive phycocyanin intensity index for estimating cyanobacteria concentrations. The development of the index was based on the reflectance difference between visible light band 620nm and 665nm. As a result of research this paper presents, an optical biological sensor design information to measure the Phycocyanin parameters in water content.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.3 s.234
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• pp.376-383
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• 2005

In the paper we investigate characteristics of a transitional behavior from a premixed flame to a triple flame in a lifted flame according to the change of equivalence ratio. In previous study, we showed that the stabilized laminar lifted flame regime is categorized by regimes of premixed flame, triple flame and critical flame. A gas-chromatograph is used to measure concentration field, a smoke-wire system is used to measure streak line, and a PIV system is used to measure velocity field in lifted flame. In the visualization experiment of smoke wire, the flow divergence and redirection reappeared in premixed flame as well as triple flame. Thus we cannot express the flame front of lifted flame has a behavior of triple flame with only flow divergence and redirection. In PIV measurement, flow velocity for those three flames has minimum value at the tip of flame front. To differentiate triple flame and premixed flame, $\Phi$ value of partially premixed fraction is employed. The partially premixed fraction $\Phi$ was constant in premixed flame. In critical flame small gradient appears over the whole regime. In triple flame, typical diffusion flame shape is obtained as parabolic distribution type due to diffusion flame trailing.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.99-104
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• 2007

Tracer gas technique is widely used to measure the ventilation rates and/or ventilation effectiveness of building spaces. However, the conventional method using a single tracer gas can measure only outdoor air change rates in a single zone. This paper deals with the multi-gas tracer technique to measure air exchange rates between rooms. Interzonal air movements are important to characterize overall ventilation performance of complicated multi-zone buildings. Experiments are conducted in a simple two-room model with known airflow rates using tracer gases of SF6 and R134a. The concentration decays of two tracer gases are measured after simultaneous injections in each room. The governing equations are derived from the continuity and the mass balance of each room. The data reduction procedure are developed to obtain the inter-room airflow rates using the governing matrix inversion, and various data manipulation methods are tested, such as data shift, interpolation, smoothing, and etc, to improve the estimate and interpretation of the results.

• Journal of Adhesion and Interface
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• v.21 no.1
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• pp.20-26
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• 2020

Single lap-shear joints (SLJ) specimens with and without partial round fillets were fabricated to measure the average shear strength of adhesives. The effects of the length of the adherend on the SLJ specimens were also investigated. An epoxy adhesive was used to bond aluminum alloy. Tensile tests were performed on the adhesive bulk specimens to measure the mechanical properties. The finite element analysis (FEA) method was used to measure the adhesive stress distributions, i.e., the peel and shear stresses, on the bonded part. The experimental results revealed that the specimen consisting short length of adherend and without the partial round fillets exhibited the smallest average shear strength of adhesive among the investigated specimens. FEA revealed that the low average shear strength for the specimen with a short adherend length was caused by high stress concentrations on the adhesive at the edge of the bonded part.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.71-76
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• 2002

A survey of radon concentrations in both indoor and outdoor atmospheres was carried out using EIRM and Cup Monitor for the period of February 1996 to March 1997. EIRM were used to measure the indoor and outdoor radon concentration at five major cities university. Cup Monitor were also used to measure the indoor radon concentrations at shopping store, office building, apartment, hospital and house in Seoul. The mean indoor and outdoor radon concentrations at the five major cities(Seoul, Daegu, Daejon, Cwangiu and Busan) were 24.1 Bq/m$^3$and 8.62 Bq/m$^3$, respectively. The ratio of indoor to outdoor radon concentrations ranged front 1.7 to 3.9. Inspection of its seasonal distribute pattern indicates the enhancement during winter relative to summer, consistently for both indoor and outdoor air. The results of the survey showed that the concentrations in basements were clearly higher than those in usual living/working places.