• Korean Journal of Construction Engineering and Management
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• v.18 no.4
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• pp.27-35
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• 2017

Based on Income-approach, this study develops the evaluation model which reflects construction industry's traits. Using Income approach, we derive future income's present value and evaluates the technological value by contribution to future income. As there exist more random variables in construction technology than in standardized manufactured products, we cannot help relying on not only quantitative estimation method but also qualitative evaluation by technology and market experts when we estimates construction technology value. Also, conservative estimation is needed for discount rate and cash-flow estimation, because of high uncertainty in sales and profits in construction industry. In empirical analysis, we applied economic periods of duration and cash-flow based on the standard guideline, and analyzed discount rate and technology factor based on characteristics of construction industry. The discount rate is estimated to 15% because of risk-premium increase by conservative evaluation. Technology factor is estimated to 46.7%, because technological intensity is estimated to 72% by technological superiority. Such implications can be inferred. Firstly, we need to build a database to diversify categories for division of sectors by activity or industrial classification which is now categorized only by two sectors in standard guideline. Secondly, the roles of experts who participate in technology evaluation are important because of volatility of construction technology.

• Korean Journal of Plant Taxonomy
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• v.42 no.1
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• pp.50-63
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• 2012

A comparative study of the petiole anatomy in the tribes Forsythieae (Abeliophyllum, Forsythia) and Fontanesieae (Fontanesia), including one related genus Myxopyrum belonging to Myxopyreae, was carried out using light microscopy. The anatomical characteristics of the distal, medial and proximal parts of the petiole were studied to document any differences. We are described in detail based on their quantitative and qualitative characteristics. Three crystal types (acicular, druse, and prismatic crystals) were found in both Fontanesia and Myxopyrum within all of the studied taxa. Uni-cellular non-glandular trichomes were found in Abeliophyllum and three Forsythia taxa (F. europaea, F. giraldiana, and F. japonica). All features were compared and the vascular patterns of the petiole were distinguished in two types: Type 1A: Trace continuous arc - without crystals (Abeliophyllum, Forsythia), 1B: with crystals (Myxopyrum), Type 2: Trace invaginating at ends with crystals (Fontanesia). A detailed anatomical description of the studied taxa is provided, and its systematic importance is also briefly discussed. In conclusion, some petiole anatomical characteristics (e.g., the main vascular patterns, the presence/absence of crystals) can be useful for diagnostic features as well as partly for supporting the recently proposed molecular phylogeny.

• Korean Journal of Veterinary Research
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• v.43 no.4
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• pp.541-549
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• 2003

The present study investigated the effects of aging on Leydig cells of Sprague Dawley rats. Rats of 3, 6, 12 and 18 months of age were used. Testes of rat were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in epon-araldite. Using $1{\mu}m$ sections stained with methylene blue, qualitative and quantitative morphological studies were performed. Testis incubations were used to determine luteinizing hormone (LH; 100 ng/ml) stimulated testosterone secretory capacity per testis in vitro. Testosterone levels in the incubation medium, and testosterone and luteinizing hormone levels in serum of these four groups of rats were determined by radioimmunoassay. Morphological studies revealed that Leydig cells were more abundant in the testis interstitium at 6, 12 and 18 months when compared with 3 months. The volumes of Leydig cells per testis was significantly higher, at 6, 12 and 18 months of age than those at 3 months. The number of Leydig cells per testis was doubled at 6, 12 and 18 months of age compared with 3 months. The average volume of a Leydig cell was not significantly different between 3 and 6 months of age, however, at 12 and 18 months a significantly lower value was observed. LH-stimulated testosterone production per testis in vitro was reduced by 45% at 6 months of age compared with 3 months; a further significant reduction was observed at 12 and 18 months. Serum testosterone and LH levels were not significantly different between 3 and 6 months of age but at 12 and 18 months a significantly lower value was observed in both groups for these hormones. These results showed that signs of aging are apparent in Leydig cells of Sprague Dawley rats at 12 months of age.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.5
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• pp.559-569
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• 2007

The purposes of this study were to find the main foulant of membrane and the optimal chemical cleaning method for MF(microfiltration) drinking water treatment system using D dam water as water source. The MF pilot plant which can treat maximum $500m^3/d$ consisted of 3 racks and was operated for 10 months under various operation conditions. After 10 months operation, $1^{st}$ and $2^{nd}$ rack of membrane pilot plant system were cleaned chemically and the degree of the restoration of the fouled membrane in terms of the pure water flux was detemnined. Inorganic compounds which contained in chemical cleaning waste was analyzed by Inductively Coupled Plasma (ICP). One membrane module for 3rd rack was disjointed and membrane fouling materials, especially inorganic compounds were investigated by Electron Probe Microanlysis (EPMA) to elucidate the reason of TMP increase. And also, the various chemical reagents (1N HCl or $H_2SO_4$, oxalic acid as acid and 0.3% NaOCl as alkali) were tested by combination of acid and alkali to determine the optimal chemical cleaning method for the MF system using micro-modules manufactured using the disjointed module. It was verified that the inside and outside of membrane module was colorized with black. As a result of the quantitative and semi-qualitative analysis of membrane foulant by ICP, most of inorganic foulant was manganese which is hard to remove by inorganic acid such as HCI. Especially, it was observed by EPMA that Mn was attached more seriously in inside surface of membrane than in outside surface of that. It was supposed that Mn fouling in inside surface of membrane might be caused by the oxidation of soluble manganese (Mn(II)) to insoluble manganese ($MnO_2$) by chlorine containing in backwashing water. The optimal cleaning method for the removal of manganese fouling was consecutive cleaning with the mixture of 1N HCl and 1% of oxalic acid, 0.3% NaOCl, and 1N HCl showing 91% of the restoration of the fouled membrane.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.3
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• pp.82-92
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• 2006

As beaches throughout Korea have suffered great losses of sand due to artificial developments and meteorological phenomena, particularly typhoons, it is necessary to monitor beaches that are prone to erosion continuously, establish and enforce a comprehensive plan to attack coastal erosion with the object of the long-term management. However, debates and temporary measures, not based on accurate coastal zone surveys and analyses, have been established up to now. Therefore, with Haeundae sand beach as a case study, we proposed methods to collect accurate spatial data of the coastline and the sand beach through GPS survey. And we detected and analyzed topographic changes resulting from Typhoon Nabi quantitatively and qualitatively, by using GIS technique. Results showed a mean elevation of 1.95 m, a total area of 53,441 $m^2$, and a total volume of 104,639 $m^3$ after Typhoon Nabi. Mean elevation rose 0.06 m between the pre- and the post-typhoon surveys by a protective shore wall. However, strong winds and north-northeast surges brought by the typhoon caused erosion of the area and the volume, by 3,096 $m^2$ and 2,320 $m^3$. Accurate spatial databases of coastal zones based on integrated GPS GIS techniques and quantitative and qualitative analyses of topographical changes will help Korea develop systematic and effective countermeasures against coastal erosion.

• Geophysics and Geophysical Exploration
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• v.14 no.4
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• pp.274-281
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• 2011

We analysed ground motions form Mw 4.3 earthquake around Backryoung Island for the seismic source focal mechanism and horizontal response spectrum. Focal mechanism of the Backryoung Islands area was compared to existing principal stress orientation of the Korean Peninsula and horizontal response spectrum was also compared to those of the US NRC Regulatory Guide (1.60) and the Korean National Building Code. The ground motions of 3 stations, including vertical, radial, and tangential components for each station, were used for grid search method of moment tensor seismic source. The principal stress orientation from this study, ENE-WSW, is consistent fairly well with that of the Korean Peninsula. The horizontal response spectrum using 30 observed ground motions analysed and then were compared to both the seismic design response spectra (Reg Guide 1.60), applied to the domestic nuclear power plants, and the Korean Standard Design Response Spectrum for general structures and buildings (1997). Response spectrum of 30 horizontal ground motions were used for normalization with respect to the peak acceleration value of each ground motion. The results showed that the horizontal response spectrum revealed higher values for frequency bands above 3 Hz than Reg. Guide (1.60). The results were also compared to the Korean Standard Response Spectrum for the 3 different soil types and showed that the vertical response spectra revealed higher values for the frequency bands below 0.8 second than the Korean Standard Response Spectrum (SD soil condition). However, through the qualitative improvements and quantitative enhancement of the observed ground motions, the conservation of horizontal seismic design response spectrum should be considered more significantly for the higher frequency bands.

• Journal of Korean Traditional Oncology
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• v.16 no.1
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• pp.41-53
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• 2011

Background and Objectives: Iodine is an essential constituent of the thyroid hormones associated with the growth and development of humans and animals as an inorganic nutrition. This element may be accumulated in human blood, tissues and body through the intake of foodstuffs, a beverage, a nutritional supplement and a medicine, among others. The aim of the research is to find out a better medicinal stuff for the thyroid cancer patient who required a low level of iodine diet. Methods: Neutron activation analysis (NAA) used for the iodine analysis is one of nuclear analytical techniques using radiation and radioisotopes and very useful as sensitive analytical technique for performing both qualitative and quantitative multi-elemental non-destructive analysis of major, minor and trace components in variety of environmental and biological materials. In this study, iodine contents in ten kinds of oriental herb medicinal products, which is frequently used to cancer patients are determined by using instrumental neutron activation analysis (INAA) at the HANARO research reactor. The samples prescribed are manufactured as powdered form for taking medicine easily. The analytical quality control is performed to assure an uncertainty of the measurement and to compensate the measured data using a biological certified reference material, NIST SRM 1572, Citrus Leaves. The measured value is $1.89{\pm}0.35mg/kg$, and the relative error is 2.88%, and relative standard deviation is 19 % due to high counting error by small counts of gamma ray spectrum. The standard deviations for other elements such as Cl, K, Mn and Na were in the range of 2 to 8%. Result: The level of iodine contents of Biki-huan, Chungryong-huan and Chungcho-huan, samples detected is less than 6 mg/kg except Hangam Plus sample (more than 210 mg/kg) and six samples were not detected. Iodine in the samples of Shoxiho-tang, Shopunghualhyl-tang, Shocungryong-tang, Banhasaxim-tang, Insampaedox-san and Myunyuk Plus were not measured, but possible level of content can be estimated from the detection limits. In addition, the concentrations of some major elements like Cl, K, Mn, Na, in the samples were determined with the detection limits. Conclusions: Most of samples showed low iodine contents of less than 6 mg/kg but it turned out that most of testing samples can be used to classify the level of iodine diet samples considering the recommended low level of iodine diet 50 ${\mu}g$/day, and a better medicinal stuff for the thyroid cancer patient can be found.

• Journal of the Korean Society of Radiology
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• v.9 no.5
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• pp.307-314
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• 2015

This study was conducted in reducing the involuntary motion artifacts because of lungs and heart movements as well as the aliasing artifacts generated during the use of the reduced-FOV EPI technique while performing breast MRI. Performed on a total of 38 obesity female subjects who visited the clinic for pre-examination before surgery within the period from August 1 to November 30, 2014. The 3.0T MRI scanner equipped with a breast scanning coil. Qualitative and quantitative analyses were each used for the evaluation of the acquired images while an Paired T-test and Wilcoxon rank test were performed to check the statistical significance. The variation ratio rose by 15.69% with the additional application of a pre-saturation pulse in the lesion, by 13.72% near the lesion, and 20.63% in the fat and the contrast-to-noise ratio rose by 10.58% in and near the lesion and by 12.03% in the lesion and fat, respectively. there were increases of 22.05% and 21.42% at 0 and 1000 respectively in qulitative evaluation and growth of 16.10% in apparent diffusion coefficient. it showed a statistically significant result(p<0.05) in signal to noise ratio, contrast to noise ratio, diffusion slope coefficient and apparent diffusion coefficient. The involuntary movements artifacts that occur in the phase encoding direction and the aliasing artifacts are considered to be reduced to obtain the best image in the additional use of the pre-saturation pulse as DWI is acquired.

• Korean Journal of Childcare and Education
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• v.11 no.3
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• pp.149-167
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• 2015

This study aims to propose the future direction of research of the Nuri-Curriculum, a national level curriculum, analyzing the subjects, the research methods, and the contents of Nuri-Curriculum studies, and current research trends. For these purposes, 102 Nuri-Curriculum articles in major child care-related journals from 2012-2015 are reviewed. PASW 18.0 program was used to calculate frequency and percentage rate. The major findings are as follows. First, a considerable amount of research has been carried out despite a relatively short implementation period. Second, many research topics dealt with include curriculum-related material. Third, 74.5 percent of the articles used quantitative methods, and content-analysis was the most widely used method among them. On the contrary, there was relatively less research which used the experimental method applying the curriculum to real practice, observational or qualitative method. Fourth, most of the research contents focus on the direction of making of the curriculum. Therefore, this paper proposes the necessity of supplementary research including its application to real practice as the research approaches on the Nuri-Curriculum performed so far have been limited.

• Spatial Information Research
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• v.5 no.1
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• pp.27-41
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• 1997

Urban land use planning is the most important core-part, and it is the start and synthetical plan of the other part, in the urban planning. For the desirable urban land use planning draw out the spatial locational character and change of urban land use. The propose of tills study is building methodology of Parcel-based Urban Land use Information Svstem(P-bULlS) and it's apphcation methodology that can be used urban planning or land use planning. To this end, each and all of the land parcels of Kangnam area was analyzed. P-bULIS should be able to easily analyze the spatial locational character and change of land use in the region. And It should be able to the qualitative, quantitative and spatial analysis, and spatial multi-variate statistical analysis can be done at relatively low cost by linking the software of statics to P-bULlS.