• Journal of Sensor Science and Technology
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• v.2 no.1
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• pp.109-115
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• 1993

A CdS single crystal was grown by using sublimation method. Lattice constants, $a_{o}$ and $c_{o}$, obtained by using extrapolation were $4.131{\underline{8}}{\AA}$ and $6.712{\underline{2}}{\AA}$, respectively. The carrier density was${\sim}10^{23}m^{-3}$ and the mobility was $2.93{\times}10^{-2}m^{2}$/V sec from measured Hall data at room temperature. The mobility has a increasing tendency in proportion to $T^{1/2}$ from 33 K to 150 K and a decreasing tendency in proportion to $T^{-2}$ from 180 K to room temperature. The short wavelength band peak measured from photocurrent was due to intrinsic transition, and the energy value of this peak was equal to the energy band gap of CdS photoconductor.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.584-589
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• 1995

To select new useful plants with antibacterial activity, ninety five sample of eighty different species of wild plants were collected, and extracted with methanol. Antibacterial activity of the methanol extracts was tested against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Vibrio parahaemolyticus. The methanol extracts from Artemisia capillaris, Hemistepta lyrata, Youngia japonica, Prunella vulgaris, Lamium amplexicaule and Juniperus chinensis was effective against all bacterial strains tested, and eight methanol extracts including Ixeris dentata, Gnaphalium affine, Chelidonium majus and Spiraea prunifolia exhibited the antibacterial activity against at least 3 bacterial strains. Methanol extracts from leaf of Syringa vulgaris, Drava nemorosa and clove of Erythronium japonicum showed a selective antibacterial activity against two gram negative bacteria, V. parahaemolyticus, and B. subtilis, respectively. With investigations on antibacterial activity against a certain bacterial strains tested, metahnol extracts from clove of Erythronium japonicum, Spiraea prunifolia, leaf and twig of Camelia japonica, and Drava nemorosa showed strongest activities against B. subtilis, S. aureus, E. coli, and V. parahaemolyticus, respectively. Nine methanol extracts based on the results were successively fractionated with n-hexane, chloroform, ethyl acetate and water portions, which were examined antibacterial activity against B. subtilis and V. parahaemolyticus. Among the all fractions tested, chloroform fractions of Hemistepta lyrata showed strongest antibacterial activity against both B. subtilis (17mm) and V. parahaemolyticus (29 mm). Chloroform fractions of Youngia japonica, n-hexane fractions of Artemisia capillaris, Iexeris dentata and Prunella vulgaris, and ethyl acetate fraction of leaf and twig of Camelia japonica showed relatively a strong antibacterial activity. On the other hand, Juniperus chinensis and Equisetum arvense was distributed to all fractions except for water fraction.

• Journal of Wetlands Research
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• v.20 no.1
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• pp.94-104
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• 2018

In general, the rainfall-runoff simulation is performed using rainfall data from meteorological and observational rain gauge stations. However, if we only use rainfall data from meteorological and observational rain gauge stations for runoff simulation of a large watershed, the problem in the reliability of the simulated runoff can be occurred. Therefore, this study examined the influence of the rainfall data on the simulated runoff volume by a Semi-distributed model. For this, we used rainfall data from meteorological stations, meteorological and observational stations, and a spatially distributed rainfall data from hypothetical stations obtained by kriging method. And, we estimated the areal rainfall of each sub-basin. Also the estimated areal rainfall and the observed rainfall were compared and we compared the simulated runoff volumes using SWAT model by the rainfall data from meteorological and observational rain gauge stations and runoff volume from the estimated areal rainfall by Kriging method were analyzed. This study was performed to examine the accuracy of calculated runoff volume by spatially distributed areal rainfall. The analysis result of this study showed that runoff volume using areal rainfall is similar to observed runoff volume than runoff volume using the rainfall data of weather and rain gauging station. this means that spatially distributed rainfall reflect the real rainfall pattern.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.800-812
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• 2005

This study selected and classified the representative foods for diversifying Korean traditional foods in the globa1 market and derived the superior factor of each food by consumer survey (n=744). The superiority of Korean traditional foods was generally recognized as being in the order of 'Nutritional value' > 'Dietary culture' > 'Material' > 'Taste.' Kimchi, Tteok/Hangwa, and grilled foods were regarded as potent Korean traditional foods for global consumers. The survey about the superior factors of representative Korean traditional foods produced the following results. The superior factor of Bibimbap, Mandu, Jangachi, Joeotgal, Namul muchim Salad, Naengchae, and Ganjang was 'Variety of material or cuisine', that of Bap, Jut Samguetang, Seolleongtang, Kimchi, Doenjang, and Sikcho was 'Nutritional value', that of Naengmyeon, Kalguksu, Bulgogi, Pyeonyuk, Jeongol, Gochujang, Tteot and Sjkhae/Sujeonggwa was Taste', and that of Hangwa, Hwachae, Gujulpan, and Sinsunro was 'Appearance'. The superior factors of representative Korean traditional foods showed the following differences by age and gender, The superior factor in Mandu was 'Taste' by the subjects aged below 30 but 'Variety' by the subjects aged above 30; that in Pyeonyuk and Jeongol was 'Variety' in 31-40 year olds and those aged above 51, while it was 'Taste' in others. The superior factor of Kimchi was 'Nutritional value' by the subjects aged below 40,'Taste'in 41-50 year. olds, and 'Variety' by the subjects aged above 50, that of Namul muchim was 'Nutritional value' by the subjects aged below 20 and 'Variety'by the subjects aged above 20, and that of Naengchae was' Taste'by the subjects aged below 20 and 'Variety' by the subjects aged above 20. The superior factor of Gochujang was 'Taste' by the subjects aged below 50 and 'Variety 'by the subjects aged above 50, that of Ganjang was 'Variety' by the subjects aged below 30 and 'Taste' by the subjects aged above 30, that of Sikcho was 'Variety' by the subjects aged below 30 and 'Nutritional value' by the sutjects aged above 30. The superior factor of Doenjang was 'Nuttritional value' in all ages. The superior factors of Hangwa and Sikhae/Sujeonggwa were 'Appearance' and 'Taste' in all ages, and that of Hwachae was 'Taste' by the subjects aged below 30 and' Appearance' by the subjects aged above 30. The perception by gender was statistically differed for traditional foods such as Bap, Bibimbap, Kalguksu, Bulgogi, Pyeonyuk Jangachi, Gochujang, Ganjang, Sikhae/Sujeonggwa, Hwachae, and Gujulpan.

• Fire Science and Engineering
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• v.31 no.5
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• pp.63-69
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• 2017

This study describes the development of a long-distance hose for ultra-high pressure operation, which can be used in conjunction with an ultra-high pressure pump and can be effectively applied to the fire suppression of high-rise buildings and a long, large tunnels. Also, it has phosphorescent properties, which can help to secure the withdrawal route of the fire-fighters when they are threatened by the fire. We developed an ultra-high pressure hose aiming at a pressure of 3 MPa and a flow rate of 2000 lpm and developed an ultra-high pressure fire hose that can withstand this very high pressure by using a double jacket, triple polyurethane coating and warf (Wp) of 52. In order to ensure the performance of the developed ultra-high pressure hose, its structure, appearance, leakage at high pressure, length and elongation were inspected by a certified certification agency, who also subjected it to a peeling test, friction test, breaking pressure test and free fall test. Also, it was studied in addition to the luminescent high-pressure hose for fire-fighting. In the phosphorescence test, the luminance measurement value was more than the reference value of the luminance test after 40 minutes, which confirmed that its performance was satisfactory for fire-fighting products. In the future, if such an ultra-high pressure fire hose were commercialized and applied in the field, it could contribute to securing improved fire suppression and safer exit from fires, as compared to the fire hoses currently used in the suppression of fires in skyscraper buildings and long tunnels.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3704-3712
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• 2012

Recently, antiwashout underwater concrete has been increasingly used for marine foundations of long span bridges. However, to shorten the construction period of antiwashout underwater concrete used in marine foundations, high fluidity antiwashout underwater concrete should be manufactured largely improving fluidity than the previous one. Thus, the objective of this experimental research is to suggest optimum mix proportions of high fluidity antiwashout underwater concrete. For this purpose, concrete specimens containing ground granulated blast furnace slag were manufactured according to the dosage of antiwashout admixture for unit binder contents of 550 and 600kg/$m^3$, respectively. And then, their quality performances such as slump flow, setting time, underwater segregation resistance, and ratio of compressive strength were evaluated according to the related specification of Korea Concrete Institute. It was observed from the test results that the minimum dosage of antiwashout admixture was necessary to satisfy the related specification.

• Journal of Korea Port Economic Association
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• v.25 no.2
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• pp.247-258
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• 2009

Rail transportation system are needed to develop proper corresponds to satisfy various demands in freight transportation since there are many problems in rail transportation infrastructure and operation. This paper analyzes characteristics of rail transportation consumers and develops policy for vitality of rail transportation by survey of rail transportation consumers and AHP methodology. This paper is organized as follows. Section 1 presents the description of the objective and the methods for this study. Section 2 presents the description of the methods for analysis of characteristics of consumers of rail freight transportation. Section 3 presents the characteristics of rail transportation consumers by analysis the survey results of rail transportation consumers. Section 4 summarizes our conclusions and discusses further research topics.

• Food Science and Preservation
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• v.11 no.1
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• pp.106-110
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• 2004

The objective of this study was carried out to investigate nutritional characteristics and biological activities effects of Korean leaf of Rosa davurica Pall. in vitro. They were extracted with methanol and then further fractionated to n-hexane, chloroform, ethyl-acetate, n-butanol and water from methanol extracts. Methods of the antigenotoxic used in this experiment were UVA/UVB absorption property and DPPH radical scavenge. The proximate compositions of leaves of Rosa dauvrica Pall were 67.5％ of crude Moisture, 0.7％ of crude fat, 6.8％ of crude protein, 6.1％ of crude ash, and 20.8％ of crude fiber. The major minerals were K (1637.2 mg％), Ca (219.5 mg％), P (182.1 mg％), and Mg (135.1 mg％). Most of the fractions of methanol extract which leaves of Rosa dauvrica Pall. have strong absorbency at UVB region (308 nm) and UV A region (350nm). These fractions have a good absorbency property as synthetic filter and could be served as substitutes for synthetic UV sunscreen agents. All fractions (n-hexane, ethyl-acetate, n-butanol and water) from methanol extracts except chloroform fraction exhibited DPPH radical scavenging activity with IC$\_$50/ of 35.3, 6.0, 14.0, and 18.0 $\mu\textrm{g}$/mL.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.5
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• pp.325-337
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• 2021

On the road and rail tunnels, the evacuation pathway and facilities such as smoke-control and fire suppression system are essential in tunnel fire. In the long twin tunnels, the cross-connection tunnel is usually designed to evacuate from the tunnel where the fire broke out to the other tunnel. In twin shield tunnels, the segment lining has to be demolished to construct the cross-connection tunnel. Considering the modern shield TBM is mostly the closed chamber type, the exposure of underground soil induced by removal of steel segment lining is the most danger construction step in the shield tunnel construction. This case study introduces the excavation method using the thrust of large steel pipe and reviews the measured data after the construction. The large steel pipe thrust method for the cross-connection tunnel can stabilize the excavated face with the two mechanisms. Firstly, the soil in front of excavated face is cylindrically pre-supported by the large steel pipe. Secondly, the excavated face is supported by the plugging effect caused by the soil pressed into the steel pipe. It was reviewed that the large steel pipe thrust method in the cross-connection tunnel is enough to secure the construct ability and stability in soil from the measurement results about the deformation and stress of steel pipe.

• 한국노년학
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• v.36 no.3
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• pp.883-903
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• 2016

The purpose of the study is examining the mediation effect of caregiver burden's segmentalized sub factors between dementia caregivers on the relationship between Symptom extent of dementia patients and Suicidal Ideation of dementia caregiver, and suggesting social welfare intervention methods for dementia caregiver The survey is targeted to demented elderly people and caregivers, and currently using medical care institution and day care center in Seoul, Gyeonggi Province and Pusan city. As a result of the survey, 415 cases were collected for the final analysis. In data analysis process, we used SPSS 21.0 for the mediation effect of conversational satisfaction and its significance, and the results are following. First, 21% of the caregivers responded that they had thoughts of suicide in the past year. Second, Symptom extent of dementia patients was positively related to caregiver burden. Third, worse in family relationships, which is sub factors of mediate variable, has partial mediate effect on the model. Based on these outcomes, we suggest the importance and necessity of improved approach about dementia elderly and caregiver between elderly couple as way to reduce caregiver burden and proposed social work-based intervention program for enhancing this.