• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.33-39
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• 2009

Asphalt waterproofing method has a long history over 80years since introduce to domestic market. This method has a good point as high water proofing not permeable to water by material performance of bitumen, In spite of high waterproofing, the application has become decreased. This asphalt method has some problem such as work safety, low workability by complicated work process, environmental problem in job site, it should be solve by complementary measures. 'Therefore, in this paper, suggest the principle of high pressure spray by heat cycle type equipment by analysis of exist problem and materials investigation. And. study and examine the spray type degeneration rubberized asphalt membrane materials to adopt job site. Moreover, suggest the evidence by inspection about waterproofing performance by Korean Industrial Standard through the performance test of the spray type degeneration rubberized asphalt membrane materials.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.58-58
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• 2022

With the development of advanced technology, automation of agricultural work is spreading. In association with the 4th industrial revolution-based technology, research on field smart farm technology is being actively conducted. A state-of-the-art unmanned automated agricultural production demonstration complex was established in Naju-si, Jeollanam-do. For the operation of the demonstration area platform, it is necessary to build a sophisticated, advanced, and intelligent field smart farming model. For the operation of the unmanned automated agricultural production demonstration area platform, we are building data on the growth of soybean for smart cultivated crops and conducting research to determine the optimal time for agricultural work. In order to operate an unmanned automation platform, data is collected to discover digital factors for water management immediately after planting, water management during the growing season, and determination of harvest time. A subsurface drip irrigation system was established for smart water management. Irrigation was carried out when the soil moisture was less than 20%. For effective water management, soil moisture was measured at the surface, 15cm, and 30cm depth. Vegetation indices were collected using drones to find key factors in soybean production prediction. In addition, major growth characteristics such as stem length, number of branches, number of nodes on the main stem, leaf area index, and dry weight were investigated. By discovering digital factors for effective decision-making through data construction, it is expected to greatly enhance the efficiency of the operation of the unmanned automated agricultural production demonstration area.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.26 no.3
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• pp.31-38
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• 2003

There is boner process of stone manufacturing to become quality down of stone to consolidated micro crack appearance of stone surface and biotite by fire that is to be route process in stone surface by flame of LPG. And then, it is develop that stone surface process equipment by automation for the work method of boner process can be substitute work method by water jet To development of equipment, There is to be down noise and dust. According to remove calamity growth hazardous substance in the work environment, there is to solve workplace avoidance factor.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.4
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• pp.391-397
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• 2004

This paper presented results of experimental and numerical work for natural convection in a square enclosure by using PIV technique. 2D PIV technique and liquid crystal are employed for velocity and temperature measurement in water. The numerical method used this work is a CFD corde, STAR-CD. The experimental work are compared with these of numerical results.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.3
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• pp.59-66
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• 1997

Although it produces well-treated water in water treatment plant, water quality at the tap can be changed depending on the state of pipes. It is because water quality deteriorates as plant water passes through pipeline networks. Therefore, the improvement of not only water treatment technology but also O & M of water pipelines is required to supply good water to consumers. The purpose of the study was to obtain the basic data of control technology for water quality in pipes through investigating water quality in distribution system. We selected 11 sampling sites and investigated water quality from plant to endpoint of distribution system. we also simulated decreasing tendency of free chlorine through pipeline network. As the result of water quality test, all parameters were below allowable levels, but some parameters had the possibility of being over levels. So there must be more work to set up proper countermeasure for violable parameters.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.4
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• pp.185-194
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• 2017

Currently, in comparison with other architectural estimations, the estimation work regarding building mechanical-service systems is time-consuming, and the process is continuously becoming more difficult because of the increased usage of the attached piping materials such as fittings and hangings in addition to their complicated construction processes. To improve this problem, the Korean authority provides a simple estimation method for the attached-material rate regarding the main piping material, which is the most time-consuming work in the architectural-mechanical estimation. However, to be an applicable method on construction sites, a proper conversion rate of the attached-piping material is still required for the proposed method regarding building usage and working types. Therefore, the purpose of this research is the calculation of the rate of the attached-piping materials such as the fittings and supports through the building of the mechanical-service work types of mechanical rooms, air conditioning, domestic water and hot-water supplies, and the drain-, vent-, and gas-piping work in office buildings that have been designed after 2010.

• Journal of the Korean Solar Energy Society
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• v.31 no.1
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• pp.15-22
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• 2011

It is a great interest to convert more energy in the heat source into the power and to improve the efficiency of power generating processes. Since the efficiency of power generating processes becomes poorer as the temperature of the source decreases, to use an ammonia-water mixture instead of water as working fluid is a possible way to improve the efficiency of the system. In this work performance of ammonia-water regenerative Rankine cycle is investigated for the purpose of extracting maximum power from low-temperature waste heat in the form of sensible energy. Special attention is paid to the effect of system parameters such as mass fraction of ammonia and turbine inlet pressure on the characteristics of system. Results show that the power output increases with the mass fraction of ammonia in the mixture, however workable range of the mass fraction becomes narrower as turbine inlet pressure increases and is able to reach 16.5kW per unit mass flow rate of source air at $180^{\circ}C$.

• Corrosion Science and Technology
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• v.12 no.2
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• pp.85-92
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• 2013

This work is concerned with an evaluation of dynamic boric acid corrosion (BAC) of low alloy steel for reactor pressure vessel of a pressurized water reactor (PWR). Mockup test method was newly established to investigate dynamic BAC of the low alloy steel under various conditions simulating a primary water leakage incident. The average corrosion rate was measured from the weight loss of the low alloy steel specimen, and the maximum corrosion rate was obtained by the surface profilometry after the mockup test. The corrosion rates increased with the rise of the leakage rate of the primary water containing boric acid, and the presence of oxygen dissolved in the primary water also accelerated the corrosion. From the specimen surface analysis, it was found that typical flow-accelerated corrosion and jet-impingement occurred under two-phase fluid of water droplet and steam environment. The maximum corrosion rate was determined as 5.97 mm/year at the leakage rate of 20 cc/min of the primary water with a saturated content of oxygen within the range of experimental condition of this work.

• Advances in nano research
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• v.5 no.3
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• pp.245-251
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• 2017

Multiwalled carbon-nanotubes (MWCNT) and micro-structured carbon, such as biochar or activated carbon (AC), have been seen to significantly increase the growth indices of certain plant species such as maize (Zea mays L.). Seed imbibition is the stage where environmental factors that affect water transport across the seed coat barrier, make a large impact. This work explores the effect on water imbibition by maize seeds when the aqueous environment surrounding the seed is diluted by small concentrations (10 and 20 mg/l) of pristine MWCNT (p-MWCNT), carboxylate functionalized MWCNT (COO-MWCNT) and AC. The degree of sensitivity of the process to (i) large structural changes is seen by utilizing the nano (the MWCNT) and the micro (the AC) allotropic forms of carbon; (ii) to small changes in the purity and morphology of the p-MWCNT by utilizing 95% pure and 99% pure p-MWCNTs of slightly differing morphologies; and (iii) to MWCNT functionalization by using highly pure (97%) COO-MWCNT. Water imbibition was monitored over a 15 hour period by Near Infrared Thermography (NIRT) and also by seed weighing. Seed surface topography was seen by SEM imaging. Analysis of the NIRT images suggests rapid seed surface topological changes with the quantity of water imbibed. While further work is necessary to arrive at a conclusive answer, this work shows that the imbibition phase of the maize seed is sensitive to the presence of MWCNT even to small differences in the purity of the p-MWCNT and to small differences in the physicochemical properties of the medium caused by the hydrophilic COO-MWCNT.

• Clean Technology
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• v.7 no.3
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• pp.215-223
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• 2001

A present semiconductor cleaning technology is based upon RCA cleaning technology which consumes vast amounts of chemicals and ultra pure water(UPW) and is the high temperature process. Therefore, this technology gives rise to the many environmental issues, and some alternatives such as electrolyzed water(EW) are being studied. In this work, intentionally contaminated Si wafers were cleaned using the electrolyzed water. The electrolyzed water was generated by an electrolysis system which consists of three anode, cathode, and middle chambers. Oxidative water and reductive water were obtained in anode and cathode chambers, respectively. In case of NH4Cl electrolyte, the oxidation-reduction potential and pH for anode water(AW) and cathode water(CW) were measured to be +1050mV and 4.8, and -750mV and 10.0, respectively. AW and CW were deteriorated after electrolyzed, but maintained their characteristics for more than 40 minutes sufficiently enough for cleaning. Their deterioration was correlated with CO2 concentration changes dissolved from air. Contact angles of UPW, AW, and CW on DHF treated Si wafer surfaces were measured to be $65.9^{\circ}$, $66.5^{\circ}$ and $56.8^{\circ}$, respectively, which characterizes clearly the eletrolyzed water. To analyze the amount of metallic impurities on Si wafer surface, ICP-MS was introduced. It was known that AW was effective for Cu removal, while CW was more effective for Fe removal. To analyze the number of particles on Si wafer surfaces, Tencor 6220 were introduced. The particle distributions after various particle removal processes maintained the same pattern. In this work, RCA consumed about $9{\ell}$ chemicals, while EW did only $400m{\ell}$ HCl electrolyte or $600m{\ell}$ NH4Cl electrolyte. It was hence concluded that EW cleaning technology would be very effective for promoting environment, safety, and health(ESH) issues in the next generation semiconductor manufacturing.