• Journal of Sericultural and Entomological Science
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• v.45 no.2
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• pp.96-102
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• 2003

This study was designed to develope the functional anti-diabetes drink, Dia-D using silkworm (Bombyx mori L) extract Sprague-Dawley (SD) male rats (160${\pm}$10g) were fed basic diet (control group), and experimental diets (SWE-l0, 30, 60 groups and Daonil-40, 80 groups) added silkworm extract 10, 30 and 60mg/day or diabetes drug prepared and marketed by Handok Pham. Co., Daonil 40 and 80 mg/day for 12 days. Blood glucose contents were significantly decreased 25-30％ in SWE-30 and SWE-60 groups, and about 35％ in Daonil 40 and Daonil 80 groups compared with control group. Triglyceride (TG) and lipid peroxide (LPO) contents were significantly inhibited 10-16％ and 8-13％, respectively, in SWE-30 and 60 groups, whereas these contents were 13-30％ and 15％, respectively, in Daonil-40 and 80 groups compared with control group. Hydroxyl radical (OH) contents were significantly inhibited 19-20％ in SWE-30 and 60 groups, and 7-12％ in Daonil-40 and 80 groups compared with control group. Superoxide dismutase (SOD) activities were significantly increased 11-14％ in SWE-30 and 60 groups, and 12-29％ in Daonil-40 and 80 groups compared with control group. In results of clinical test using normal subjects, blood glucose content tested in NIAST subjects as anti-diabetes drink, Dia-D willi 100mg/vial was significantly decreased 17.5％, and these content tested in PKNU subjects as anti-diabetes drink, Dia-D with 150mg/vial was significantly decreased 20.5％ compared with control group. These results suggest that administration of Dia-D as an anti-diabetes drink prepared with silkworm extract may playa very effective role in a decreasing of blood glucose in hyperglycemia patients.

• Journal of Welding and Joining
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• v.5 no.1
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• pp.64-72
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• 1987

The Weldability of gavannealed steel using spot welder has been studied. The Results obtained are a follows; 1) Welds size and strength were increased depending on the welding time and welding current. But, the increasing rate has been decreased. 2) Deposited zinc has affected on the wear of welding tips and growth of welds but has not affected the weld's structures. 3) On shear testing of the specimen, button fracture has been observed and the value was approximately 540Kg (welds dia. approximately .phi.4mm)

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.9
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• pp.1115-1125
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• 1997

Experiments have been conducted to obtain local and average heat transfer coefficients associated with impingement of a row of circular, free surface-water jets on a constant heat flux surface. Nozzle arrays are a row of 3 jets (nozzle dia.=4.6 mm) and a row of 5 jets (nozzle dia.=3.6 mm), and the nozzle configuration is Reverse cone type revealed good performance in heat transfer. Nozzle-to-plate spacings ranging from 16 mm to 80 mm were investigated for two jet center to center spacings 25 mm and 37.5 mm in the jet velocity of 3 m/s (R $e_{D}$=27000) to 8 m/s (R $e_{D}$=70000). For a row of 3 jets and a row of 5 jets, the stagnation heat transfer of the central jet is lower than that of adjacent jets. In the wall jet region between jets, for small nozzle-to-plate spacing and large jet velocity, the local maximum in the Nusselt number was observed, however, for small jet velocity or large nozzle-to-plate spacing, the local maximum was not observed. Except for the condition of $V_{O}$=8 m/s and H/D=10, the average Nusselt number reveals the following ranking: a row of 5 jets, a row of 3 jets, single jet. For a row of 3 jet, the maximum average Nusselt number occurs at H/D=8 ~ 10, and for a row of 5 jets, it occurs at H/D=2 ~ 4. Compared with the single jet, enhancement of average heat transfer for a row of 3 jets is approximately 1.52 ~ 2.28 times, and 1.69 ~ 3.75 times for a row of 5 jets.ets.s.

• Transactions of the Korean Society of Mechanical Engineers
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• v.8 no.5
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• pp.442-449
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• 1984

Turbulent jet flow has been studied in many ways; a plane jet, a rectangular jet, an annular jet, a round jet, a wall jet, a parallel jet, a valve jet, a cross jet, a slit jet and etc. In this report, a 45.deg. cross jet flow was tried by using two same dimensioned nozzels(dia..phi.20)which were set up at the exit of the subsonic wind tunnel. Each jet flows to the direction of 22.5.deg. to the axis of downstream of the mixed flow. The centerline of each jet meets at the distance of 217.3mm and their mixing flow could be imagined to develop beyond that distance, so the measurement was effectuated at X/X$_{0}$=1.2-1.5. The section of the mixed flow a elliptic circle which is formed by the 22.5.deg. inclined flows to the X direction. This experimental study aimed at the investigation of the turbulent mixing process of two jets; the mean velocities, the turbulent shear stresses, the correlation coefficients, and the momentum were respectively measured. The mean velocity distribution profiles of the down-stream component measured in the Y direction coincide well with the empirical equation of Gortler and those measured in the Z direction agree with the equation of H. Schlichting. Other mean velocities V over bar and W over bar components were randomly distributed. The higher values with same order of the intensity of turbulence were largely distributed at the central part of the flow. The momentum was decreased up to 70% by the shock losses and the development of intense turbulences, but it kept its value constantly beyond X/d=14. Two-channel hot-wire anemometer systems (model 1050 series), X-type hot-wire made of tungsten (dia. .phi.e.mu.m, long 3mm, model 0252 T5), a computer(model HP 9845B0, and a plotter (model HP 9872C) were used for the experiments and the analyses.s.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.483-492
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• 2021

Agastachis Herba (AH) to treat anorexia and nausea and its antidiabetic efficacy was recently reported. This study examined the antioxidant activities and chemical constituents of AH and predicted the target proteins of each compound using in silico approaches. The results showed that EC50 values of AH methanol extract for DPPH and ABTS radical scavenging were 78.6 ㎍/mL and 31.0 ㎍/mL, respectively. Compared to the EC50 values of ascorbic acid (9.9 ㎍/mL, 5.2 ㎍/mL), the AH methanol extract possessed excellent antioxidant activities. Rosmarinic acid, tilianin, agastachoside, and acetin were confirmed as the major compounds of extracts by qualitative analysis performed with HPLC-PDA-MS/MS. The antidiabetic target proteins of these compounds were predicted by applying a structural similarity and inverse docking methodology using a DIA-DB server. The resulting target proteins were PPAR-γ, DPP IV, glucokinase, α-glucosidase, SGLT2, aldose reductase, and corticosteroid 11-beta-dehydrogenase, some of which have already been proven experimentally as target proteins. Therefore, the in silico methods can be considered valid. Finally, AH were extracted with various solvents to determine the optimal conditions for the extraction of active components. Methanol among organic solvents and 80% ethanol in ethanol-water mixtures were identified as the most effective solvent for the extraction.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1839-1850
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• 2009

The Korean railway system is a mass transit system in which a various types of trains such as common trains, high-speed train (KTX), Metropolitan Express Railway (EMU) are operated. It is operated based on a timetable and provides us with safety, regularity, quickness and comfortable service. The objective of this study is to propose a method for estimating line capacity considering high-speeding and diversification of trains. In particular, the focus of this study is on the closing gap between the result of the existing line capacity estimation method and the real-world line capacity of the operating agency of the Korean railway. For this, this study introduces a new railway capacity definition by considering TPS of line alignment according to the operation type, train control and signaling system, etc. The verification of the proposed method using a practical schedule diagram exemplification is discussed as well.

• Polymer(Korea)
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• v.29 no.1
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• pp.102-105
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• 2005

Photoinitiated polymeric dental restorative nanocomposites (PDRNC) were designed to be useful for the variety of dental restoration. Hybrid-filler composed of barium silicate (avg. dia.:1 ${\mu}m$) and nano-sized silica (avg. dia: 40 and 7 nm) was adopted as a filler system. To improve the interfacial behavior with the resin matrix of bisphenol A glycerolate methacrylate/triethyleneglycol dimethacrylate (60/40 wt%), the surface of the filler was hydrophobically treated with a silane coupling agent. A visible light system of camphorquinone photo-initiator and 2-(dimethylamino)ethyl methacrylate photo-accelerator was utilized to activate the PDRNC. Esthetic properties of PDRNC was investigated by measuring the Hunter L, a, b values and it was discovered that PDRNC produced in this work showed excellent esthetic properties with an increase in 7 nm nanofiller content.

• Journal of the Korean Society for Railway
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• v.12 no.5
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• pp.623-630
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• 2009

The Korean railway system is a mass transit system consisting of a variety of train types such as common trains, high-speed train (KTX) and Metropolitan Express Railway (EMU). Its operation is based on the official timetable and it provides us with safe, accurate, quick and comfortable service. The objective of this study is to propose and prove more practical method for estimating line capacity by considering high-speeding and diversification of trains. In particular, the focus of this study is to reduce the discrepancy between the result of the theoretical line capacity estimation and the real line capacity of the operating agency of the Korean railway. In order to achieve the object, this study introduces a new railway capacity notion by considering TPS of line alignment, the operation type, train control and signaling system, etc. Through a practical schedule diagram exemplification, the result of the proposed method is verified as well.

• Advances in concrete construction
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• v.8 no.3
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• pp.207-215
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• 2019

Application of nanotechnology can be used to tailor made cementitious composites owing to small dimension and physical behaviour of resulting hydration products. Because of high aspect ratio and extremely high strength, carbon nanotubes (CNTs) are perfect reinforcing materials. Hence, there is a great prospect to use CNTs in developing new generation cementitious materials. In the present paper, a parametric study has been conducted on cementitious composites reinforced by two types of multi walled carbon nanotubes (MWCNTs) designated as Type I CNT (10-20 nm outer dia.) and Type II CNT (30-50 nm outer dia.) with various concentrations ranging from 0.1% to 0.5% by weight of cement. To evaluate important properties such as flexural strength, strain to failure, elastic modulus and modulus of toughness of the CNT admixed specimens at different curing periods, flexural bending tests were performed. Results show that composites with Type II CNTs gave more strength as compared to Type I CNTs. The highest increase in strength (flexural and compressive) is of the order of 22% and 33%, respectively, compared to control samples. Modulus of toughness at 28 days showed highest improvement of 265% for Type II 0.3% CNT composites. It is obvious that an optimum percentage of CNT could exists for composites to achieve suitable reinforcement behaviour and desired strength properties. Based on the parametric study, a tentative optimum CNT concentration (0.3% by weight of cement) has been proposed. Scanning electron microscope image shows perfect crack bridging mechanism; several of the CNTs were shown to act as crack arrestors across fine cracks along with some CNTs breakage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.5
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• pp.695-699
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• 2003

Traditional soybean sprouting bucket has some problems which are putrefaction and growing inhibition by the high temperature and carbon dioxide in the bucket during culturing. To solve this problems we developed the new soybean sprouting bucket. The new bucket consisted a square shaped bottom which has 5 draining holes (each 10 mm in dia, 2 mm in height) and four side wall which has two rectangular shaped holes (10 cm long, 0.5 cm wide), and the support vessel which 592 tiny draining holes whose center attached a pipe with 36 small holes (each 2 mm in dia). The new one showed lower temperature and carbon dioxide content during culturing, and the putrefaction was lower, whereas growing degree was higher during culturing at 25$\pm$1$^{\circ}C$ than the traditional bucket.