• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.4
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• pp.69-76
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• 2010

After feeding mixed samples, VS ranged from 60 to 80% of total costs in 15 days. EC ranged from1.21 to 2.45, 1.25 to 2.1 and 1.2 to 1.88mS/cm when worms were fed with a mixture of by-products of tidal current and sewage sludge, a mixture of by-products of algae producy, and food wastes and a mixture of by-products of algae producy, sewage sludge and food wastes. That means the kinds of mixture don't have any negative impacts on worms survival. With the feed with a mixture of by-products of algae producy and food wastes and a mixture of by-products of algae producy, sewage sludge and food wastes, pH shows stable 5.4 to 6.7, and 6.2 to 7.4 where is suitable for worms. But a mixture of by-products of algae producy and sewage sludge is out of proper scope for raising worms, in other words, extra care will be necessary. In case of Eh, a mixture of by-products of algae producy and sewage sludge make eh negative (-) in early stage so also when feeding worms, also extra care will be needed. NaCl ranged from 0.32 to 0.82% or form 0.23 to 0.61% when a mixture of by-products of algae producy and food wastes and a mixture of by-products of algae producy, sewage sludge and food wastes were fed. So taking care of salts will be essential whenever feeding.

• Journal of Energy Engineering
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• v.25 no.3
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• pp.41-50
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• 2016

This study examined the combustion characteristics and emissions, fuel economy, acceleration by selecting the two fuel with octane number difference to investigate the effect on the combustion characteristics and performance of the vehicle according to the octane number. First, a single-cylinder engine was used for the combustion characteristic experiment, Of the fuel, which is distributed on the market by the selection of two different octane fuel it is performed experiments. Single cylinder experiment examined the combustion characteristics that appear when you gradually advancing the ignition timing by the ignition timing and air-fuel ratio control for each fuel and through an output, emissions, pressure, hence examined the correlation between by octane number. In addition through the actual vehicle compared the changes in the fuel octane number difference, through acceleration tests examined the impact of the octane number requirements for high-performance segment. As a result, fuel of high octane number in accordance with the ignition timing the advancing showed a slightly stable combustion characteristics, a slight increase occurred in the acceleration test and power. However, both fuel does not significantly differ from the current mode, simulating the urban and highway fuel efficiency. Therefore, the operating conditions of the vehicle currently being sold on the Effects of high-octane fuel. fuel efficiency was found insufficient.

• Korean Security Journal
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• no.60
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• pp.175-196
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• 2019

The purpose of this study is to examine the role of safety sheriffs and their necessity in order to improve the activation of safety sheriff's professionalism. Seven security sheriffs were finally selected to discuss their activities and discuss ways to improve their effectiveness. We conducted semi - structured interviews and conducted in - depth interviews with limited data and inadequate prior research. The results of this study are as follows. First, the government should get the help of citizens, citizens and residents. If the state wishes to reduce the number of safety accidents and bring positive results to the public, it should not rely solely on the utilization of institutions. Second, in order to be a safe sheriff with a positive response from the local residents, the activities of the sheriff's sheriff are not only aimed at preventing risks in the environmental domain and reducing the number of accidents, Publicity should be provided to the landlord, tenant, and residents to inform them that the activity is preventive of accident prevention. Third, under the current law, it is necessary to disclose public facilities such as roads, airports, and harbors to the private sector in order to make it possible to monitor school facilities and youth training facilities. Fourth, the safety sheriff is expected to put forward the expectations and positive results of prevention through the beginning of the inspection activities, and the role of the Korean people in becoming psychological stable and efforts to be born as safety experts are required. Finally, it is necessary to establish a concrete manual, strategic safety inspection plan.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.1
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• pp.58-66
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• 2013

This study was conducted in order to develop slaughterhouse rumen content (SRC) as a potential feed additive. The moisture content of SRC can reach 80%, and therefore an appropriate dewatering process is required before it can be used. In this study, the effects of heating temperature, heating time, and filler content during the dewatering process on the activity of various enzymes in SRC were investigated. The Box-Behnken experimental design was employed, involving a total of 45 experimental runs, consisting of three variables (heating time, heating temperature, and filler content) with three levels per variable (12, 30 and 48 hr; 60, 75 and $90^{\circ}C$; 12, 22.5 and 33% for heating time, heating temperature, and filler content, respectively). For enzyme activities, xylanase, cellulase, and amylase were examined, and the results were subjected to an analysis of variance. Heating time, heating temperature and filler content had significant effects on the activity of each enzyme (p<0.05). Cellulase and amylase activities decreased (p<0.05) at elevated heating temperatures, whereas xylanase was reasonably stable around $90^{\circ}C$. The activities of all enzymes decreased (p<0.05) with increased heating time. Optimum filler contents for xylanase, cellulase, and amylase activities were 22.5, 12 and 33%, respectively. However, optimum conditions for all variables that simultaneously maximize the activity of all three enzymes could not be ascertained in this study. Nevertheless, the results from the current study can be useful as basic information for the development of SRC as a feed additive enriched with improved major enzymes for livestock feed digestion.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.3
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• pp.207-217
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• 2008

The SSTop (Sea Surface Topography) provides an estimate of the large scale structure of the deviations between the geoid height and the mean sea surface in terms of a normalized surface spherical harmonic series. The SSTop is the key information which has been used to determine the shape of earth, geoid, current and tide etc. Also, the SSTop is a basic source for the unification of vertical datums at the different height systems which were established according to the their respective purposes. In order to unify the vertical datum around the East-Asian (E-A) region (covers the area: $20^{\circ}-45^{\circ}N$ and $110^{\circ}-140^{\circ}E$), we estimated the value of SSTop in the E-A region using the predicted values of mean sea surface (from KMSS04) and geoid height (from EGM96 and EIGEN-GL04C) and analyzed to aspect of SSTop at 5 tidal stations (InCheon, JeJu, QingDao, Aburatsubo, KeeLung) with the estimated values of each station previously. The result from this study indicates that the SSTop in the E-A region is relatively stable except for the area around the Japanese and Ryukyu deep, and also shows that the distribution of values of SSTop is ranged from 40 to 60 cm at tidal stations except InCheon station.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.360-369
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• 2008

The solar cells should be operated at the maximum power point because its output characteristics were greatly fluctuated on the variation of insolation, temperature and load. It is necessary to install an inverter among electric power converts by means of the output power of solar cell is DC. The inverter is operated supply a sinusoidal current and voltage to the load and the interactive utility line. In this paper, the proposes a photovoltaic system is designed with a step up chopper and single phase PWM voltage source inverter. Synchronous signal and control signal was processed by one-chip microprocessor for stable modulation. The step up chopper is operated in continuous mode by adjusting the duty ratio so that the photovoltaic system tracks the maximum power point of solar cell without any influence on the variation of insolation and temperature for solar cell has typical dropping character. The single phase PWM voltage source inverter is consists of complex type of electric power converter to compensate for the defect, that is, solar cell cannot be develop continuously by connecting with the source of electric power for ordinary using. It can be cause the efect of saving electric power, from 10 to 20%. The single phase PWM voltage source inverter operates in situation, that its output voltage is in same phase with the utility voltage. The inverter are supplies an ac power with high factor and low level of harmonics to the load and the utility power system.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2008.05a
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• pp.47-70
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• 2008

Cost efficiency is today the primary requirement in the paper and board industry. This has led therefore, to a greater preponderance of products with specifically designed functionality to take account of current industry needs. Continually increasing machine coating speeds together with these new coating colour components have put more emphasis on the importance of the correct rheology and water retention of the coating colours to achieve good runnability and end product quality. In the coating process, some penetration of the aqueous phase, to the base paper or board must occur to anchor the pre-coating to the base or the topcoat to the pre-coat. The aqueous phase acts as a vehicle not only for the binder, but also for the other components. If this water or material penetration is not controlled, there will be excessive material shift from the coating colour to the base, before immobilization of the coating colour will stop this migration. This can result in poor machine runnability, unstable system and uneven coating layer, impacting print quality. The performance of rheology modifiers or thickeners on the coating color have tended to be evaluated by the term, "water retention". This simple term is not sufficient to explain their performance changes during coating. In this paper we are introducing a new concept of "material retention", which takes note of the total composition of the coating colour material and therefore goes beyond the concept of only water retention. Controlled material retention leads to a more uniform z-directional distribution of coating colour components. The changes that can be made to z-directional uniformity will have positive effects on print quality as measured by surface strength, ink setting properties, print gloss, mottling tendency. Optical properties, such as light scattering, whiteness and light fastness delivery should also be improved. Additionally, controlled material retention minimizes changes to the coating colour with time in re-circulation giving less fluctuation in quality in the machine direction since it more closely resembles fresh coating for longer periods. Use of the material retention concept enables paper and board producers to have more stable runnability (i.e. lower process costs), improved end product quality (i.e. better performance of used chemicals) and/or optimized use of coating colour components (i.e. lower total formulation cost)

• Land and Housing Review
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• v.3 no.4
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• pp.423-431
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• 2012

The trends of Green growth and environmentally-friendliness came to be the key development indicator for sustaining global environment for the future. Korean government reflected these trends in the main flows of the national development index. Korean construction industry is concentrating investment on fields related to these trends such as technologies for carbon dioxide deduction, materials or products for environmentally-friendly building and alternative energy development, as well. However, efforts to follow these trends during the construction process as a step for production phrase are not being considered enough. In this study, we analysed current status and points to be improved of on-site environment management by surveying major project owners and representatives of the environmental affairs in the leading companies of those fields. Also, we suggested organizational structure and operation model as a solution for enhancing environmentally-friendliness for systematic approach to manage on-site environment in public construction sites. In addition to these solutions, further approaches such as shifting paradigm of project owners and contractors, securing workforce and practical budget for efficient management activities, developing environmental management manuals, setting standards for evaluation of activities are needed for the stable settlement of on-site environmental management.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.240-240
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• 2011

The first neutral beam injector (NBI-1) has been developed for the Korea Superconducting Tokamak Advanced Research (KSTAR) tokamak. A first long pulse ion source (LPIS-1) has been installed on the NBI-1 for an auxiliary heating and current drive of KSTAR core plasmas. Performance of ion and neutral beam extractions in the LPIS-1 was investigated initially on the KSTAR NBI-1 system, prior to the neutral beam injection into the main plasmas. The ion source consists of a JAEA magnetic bucket plasma generator with multi-pole cusp fields and a set of KAERI prototype-III tetrode accelerators with circular apertures. The inner volume of plasma generator and accelerator column in the LPIS-1 is approximately 123 liters. Final design requirements for the ion source were a 120 kV/ 65 A deuterium beam and a 300 s pulse length. The extraction of ion beams was initiated by the formation of arc plasmas in the LPIS-1, called as an arc-beam extraction method. A stable ion beam extraction of LPIS-1 has been achieved up to an 100 kV/42 A for a 4 s pulse length and an 80 kV/25 A for a 14 s pulse length. Optimum beam perveance of 1.21 microperv has been found at an accelerating voltage of 80 kV. Neutralization efficiency has been measured by using a water flow calorimetry (WFC) method of calorimeter and an operation of bending magnet. The full-energy species of ion beams have been detected by using the diagnostic method of optical multichannel analyzer (OMA). An arc efficiency of the LPIS was 0.6~1.1 A/kW depending on the operating conditions of arc discharge.

• Korean Journal of Materials Research
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• v.4 no.2
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• pp.143-151
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• 1994

On PT/Ti/Si substrates, PZT thln fllms are deposited at $300^{\circ}C$ by rf magnetron sputtering uslng a $(PbZr_{52}, Ti_{48})O_{3}$ composltc cerarnlc target. To abtaln, the stable phase, perovskltc structure, furnace annealmg techmque had been cmplo:~d In PbO amb~ent for the $550^{\circ}C$-$750^{\circ}C$ temperature ranges. On Pt(250$\AA$)/Ti(500$\AA$)/Si, Pt(1000)$\AA$/Ti(500$\AA$)/Si substrates, effects of Ti layer and Pt thickness are studled. Though thickness of the Pt layer 1s 1000$\AA$). oxygen diffusion is not prevented and accelerated by Ti layer actlng for oxygen sink sites durmg furnace annealing. The upper TI layer 1s transformed Into TIOX by oxyen dlffuslon and lower Ti layer Into silicide with in-diffused Pt. The formation of TiOx layer seems to affect the orlentatton of the PZT layer. Furnace annealed f~lm shows ferroelectr~c and electrical properties wth a remanent polarlzation of 3.3$\mu A /\textrm{cm}^2$, , coerclve fleld of 0.15MV/cm, a=571 (10kHz), leakage current 32.65$\mu A /\textrm{cm}^2$, , breakdown voltage of 0.4OMV/cm.