• Journal of Surface Science and Engineering
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• v.42 no.4
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• pp.179-185
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• 2009

Diamond-like carbon(DLC) films were deposited by linear ion source(LIS)-physical vapor deposition method changing the anode voltages from 800 V to 1800 V, and characteristics of the films were investigated using residual stress tester, nano-indentation, micro raman spectroscopy, scratch tester and Field Emission Scanning Electron Microscope(FE-SEM). The results showed that the residual stress and hardness increased with increasing the ion energy up to anode voltage of 1400 V. It was also found that the content of $SP^3$ carbon increased with increasing the anode voltage $SP^3/SP^2$ ratio through investigation of $SP^3/SP^2$ ratio by the micro-raman analysis. From these results, it can be concluded that the physical properties of DLC films such as residual stress and hardness are increased with increasing the anode voltage. These results can be explained that 3-dimensional cross-links between carbon atoms and Dangling bond are enhanced and the internal compressive stress also increased with increasing the anode voltage. The optimal anode voltage is considered to be around 1400 V in these experimental conditions.

• The Journal of the Acoustical Society of Korea
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• v.26 no.6
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• pp.235-242
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• 2007

The test and evaluation of floor impact sound is mainly conducted before move in the residence. Floor impact sound generating is actually the conditions in which a heavy load like a curtain and furniture is installed, the situation before and after move in the residence is different. In this study, we investigate the floor impact sound variations according to the live load installation like furniture in the source room. The vibration acceleration level and floor impact sound level variation were measured before and after live load ($200kg/m^2$) installation in the floor impact sound test building and the field. The difference was not large although the vibration acceleration level and the floor impact sound level were reduced through measurement result of load installation. Resonance frequency was not changed by load installation.

• The Journal of Sustainable Design and Educational Environment Research
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• v.16 no.2
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• pp.19-33
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• 2017

The purpose of this study is to derive education programs for safety training class, create unit spaces and present components and methods of utilizing the spaces for the development of facilities models closely related to various policy, operation plan and facility construction projects promoted by related institutions such as the Ministry of Education, schools, architects and companies. This study is divided into five steps. First, we reviewed the literature related basic directions for safety education and facility plan, second, field survey included both field conditions such as spatial size and facility configuration and analysis of operating conditions like hours of operation and personnel. Base on literature review and field survey, it were used to analyze strengths and weaknesses of existing safety training classes, and five facility models was developed based on the Delphi method and expert participatory design. The result show that the facility models (drafts) of safety training class were developed as follows: (1)the facility model for traffic safety(pedestrian safety, vehicle safety, subway safety) (2)the facility model for first aid(emergency rescue, how to report) (3)the facility model for disaster safety(fire evacuation safety, life earthquake safety) (4)the facility model for elevator safety(elevator safety, escalator safety) (5)the facility model for drugs and violence safety (smoking drinking, sexual harassment safety, food safety) The safety training class can be composed by combining or separating each module according to affordable space size of each school.

• Journal of Biosystems Engineering
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• v.38 no.2
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• pp.73-80
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• 2013

Purpose: This study was conducted to compare tillage and loads characteristics of three types of rotavators in farmland working condition of Korea. Methods: Tillage operations using three types of rotavators, i.e. rotary-type, crank-type and plow-type, were carried out in a dry field of Korea. The same prime mover tractor was used for driving three types of rotavators, and under several operational conditions, tillage characteristics such as actual working speed, rotavating depth, rotavating width, actual field capacity, flow of tilled soil, soil inversion ratio, and pulverizing ratio were measured. In addition, loads characteristics like torque and required power of Power Take-Off (PTO) shaft were calculated. Results: The average rotavating depth was smaller than the nominal value for all rotavators, and the difference was the greatest in the plow-type rotavator. Nevertheless, the plow-type rotavator showed the largest rotavating depth. The rotavating width was the same as the nominal value of all rotavators. The flow of tilled soil at the same operational conditions was the greatest in the plow-type rotavator and was the smallest in the rotary-type rotavator. In the most commonly used gear conditions of L2 and L3, the average soil pulverizing ratio was the greatest in the rotary-type rotavator, and followed by crank-type and plow-type rotavators in order. In the gear L2 and L3, the plow-type rotavator also had the lowest average soil inversion ratio while the rotary-type and crank-type rotavators had the same soil inversion ratio each other. The average torque and power of PTO shaft in the gear L2 and L3 were the highest in the plow-type rotavator. The load spectra of PTO shaft applying rain flow counting method and Smith-Waston-Topper equation to the measured torque showed that the modified torque amplitude was the greatest in the crank-type rotavator. This may come from the large torque fluctuation of crank-type rotavator during tillage operations. Conclusions: The three types of rotavators had different tillage and loads characteristics. The plow-type rotavator had the deepest rotavating depth, the smallest soil inversion ratio, the largest soil pulverizing ratio and required PTO power. Also, the crank-type rotavator showed a large torque fluctuation because of their unique operational mechanism. This study will help the farmers choose a suitable type of rotavator for effective tillage operations.

• Journal of Ginseng Research
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• v.24 no.3
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• pp.134-137
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• 2000

Spontaneous bursting activity was studied in rat thalamocortical slices using extracellular field potential recording to test the potential utilization of ginsenoside Rb$_1$ in controlling overactivated neural systems. In order to induce bursting activity, slices were perfused with Mg$\^$2+/-free artificial cerebrospinal fluid (ACSF). Two major types of spontaneous bursting activity, simple thalamocortical burst complexes (sTBCs) and complex thalamocortical burst complexes (cTBCs), were recorded in Mg$\^$2+/ -free ACSF. Ginsenoside Rb$_1$ selectively suppressed cTBCs. Duration and occurrence rate of cTBCs were reduced by 87.3${\pm}$10.2% and 85.3${\pm}$ 14.7% in the presence of 90 ${\mu}$M ginsenoside Rb$_1$ respectively, while amplitude and intraburst frequency were slightly changed by ginsenoside Rb$_1$. In contrast, ginsenoside Rb$_1$was much less effective in reducing duration and occurrence rate of sTBCs. We also tested effects of ginsenoside Rb$_1$ on bursting activity in the presence of a GABA$\sub$A/ receptor antagonist, bicuculline methiodide (BMI). Ginsenoside Rb$_1$ had no effect in suppressing BMI-induced bursting activities. These results suggest that ginsenoside Rbi may be useful in controlling seizure-like bursting activity under pathological conditions.

• Geomechanics and Engineering
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• v.12 no.5
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• pp.739-752
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• 2017

This study was intended to evaluate the improved strength of the ground by applying the bio grouting method to a loose sandy ground. The injection material was prepared in the form of cement-like powder, with the bio injection material produced by microbial reactions. The grouting test was conducted under the conditions similar to the field where the bio injection material can be applied. In addition, the injection materials (cement and sodium silicate No. 3) used for Labile Waterglass (LW) method and the conventional grouting methodwere prepared through a two-solution one-step process. The injection into the specimens was done at a pressure of 150 kPa and then, with a bender element, their moduliof elasticity were measured on the 7th, 14th, 21st and 28th curingdays to analyze their strengths according to the duration of curing. It was confirmed that in all injection materials the moduli of elasticity increased over time. In particular, when 30% of the bio injection material was added to 100% cement, the modulus of elasticity tended to increase by about 15%. This confirmed that the applicability became higher when the bio injection material was used in place of the conventional sodium silicate.

• Journal of Animal Science and Technology
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• v.57 no.9
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• pp.29.1-29.9
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• 2015

This review provides an overview of the published data on the canola meal and its suitability for duck as an alternative plant-origin protein source to soybean meal. Canola meal is a legume origin protein source containing comparable amino acid profile to soybean meal and rich in essential minerals and vitamins. Nonetheless, it is known to contain less in energy content than soybean meal. Factors like field conditions and processing methods creates compositional variations among canola meal. Presence of anti-nutritional factors such as phenolic substances, phytate and glucosinolates which are known to reduce growth performance in livestock animals, are the major drawbacks for canola meal to be a competitive plant-origin protein source in the feed industry. This review is focused to address i) nutritional characteristics and feeding value of canola meal for ducks and ii) impacts of feeding canola meal on performances of ducks.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.363-369
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• 2002

Orifice meter is the most widely used flowmeter in custody transfer between KOGAS and city gas companies. Absolute pressure value is needed to calculate the gas flow of orifice metering system, but the gauge pressure transmitters are mainly used in the field. In case that the gauge pressure transmitters are used, the fixed value as standard atmospheric pressure(101.325kPa) is applied for the absolute pressure value. The real, local atmospheric pressures of each metering station are different from the standard condition as the altitude and weather conditions. In this study the flow calculation errors were quantitatively analyzed through examining the atmospheric pressures of 50 stations of KOGAS. The data for analysis are such like the time data of supplied gas amount, the altitude of each metering station, the time data of atmospheric pressures and altitudes of each weather observatory. The results showed that the local atmospheric pressures were different from the standard value and the gas flow calculation errors were distributed between $-0.024\%{\~}0.025\%$ based on the supplied gas amount in the year 1999 and 2000.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.4
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• pp.379-386
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• 2016

As well as to operate a high-speed rail, our country with capability to produce high-speed train has developed a number of techniques, such as for a riding comfort improvement, automatic diagnosis for major electrical or mechanical parts, on board measurement for catenary systems and noise reduction of running rolling-stocks are still under development. In this paper, we describe the current status of operation technologies not only traditional railway wireless communication systems but also Long Term Evolution systems which would be deployed as soon as possible, like as in Europe, China and the United States. In addition, we produced the domestic wireless communication networks for railway which KORAIL Corp. has been operating and the schemes and the plans of HSR field test for the fourth generation mobile communication which should be enforced by national research and development.

• The International Journal of Costume Culture
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• v.12 no.2
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• pp.121-128
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• 2009

The goal of this study is to investigate the current conditions of apparels for the handicapped, identify the problems and recommend what are appropriate and functional apparels for the handicapped. The research method was to statistically process a survey on 200 handicapped by frequency analysis and cross tabulations. The study results are as follows. First, the degree of discomfort in daily activities was shown during toilet use and eating. Among clothes categories owned by the handicapped, most discomfort was felt in the order of everyday clothes, workout clothes, underwear, athletic shoes and working clothes. Second, children's clothing was most commonly preferred clothing style by handicap for the dwarfism. Comfortable clothes was preferred and relaxed, decent, and unique styles were preferred in the order. Soft feeling texture and absorbency was considered important as preferred clothing material. Third, sizes and designs were improvements wanted by the handicapped in apparel in the order. In addition, they wanted to wear apparel sensitive to the fashion just like the non-handicapped without showing the handicapped parts. There is a necessity for the government or municipalitiesto establish and run protected workplaces or independent workplaces for those who have studied apparel. The field is thought to require continuous and numerous follow-up studies such as researches on different physiques, standardization of apparel, segmentation of sizes and methods of producing custom apparel by function and handicap.