• Journal of Environmental Science International
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• v.23 no.8
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• pp.1429-1436
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• 2014

In this study, we investigated the effects of dietary supplementation (n = 40 pigs/treatment) with bamboo powder (0, 1, 2 and 3%) for 38 days. We evaluated growth performance, blood metabolites, and carcass characteristics of fattening pigs and gas emission and microbial populations in pig manure, to obtain data on pork producers for environmental management. We obtained the following results. First, supplementation with increasing amounts of bamboo powder had a significant (P < 0.05) effect on feed intake, feed efficiency, and glucose contents (except for initial and final body weight, weight gain, carcass characteristics, and blood urea nitrogen). In terms of blood metabolites, glucose and blood urea nitrogen tended to decrease with increasing amounts of bamboo powder. Second, the amounts of ammonia, methane, amine, hydrogen sulfide, and acetic acid were reduced by increasing amounts of bamboo powder when compared with the controls (P < 0.05). However, there were no significant differences in pH, propionic acid, iso-butyric acid, butyric acid, iso-valeric acid, and valeric acid among all treatments. The lowest gas emission was observed when 3% bamboo powder was used. Third, supplementation with increasing amounts of bamboo powder tended (P < 0.05) to increase the total number of bacteria, Lactobacillus spp., and yeast, but E. coli, Salmonella spp., and Shigella spp. were not detected in any treatment. In conclusion, the results of this study suggest that supplementation with bamboo powder was effective in reducing gas emission and inhibiting pathogen populations in pig manure by lowering the pH of the manure.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.12
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• pp.863-870
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• 2012

The market trends of automatic meter reading associated with smart water meters were investigated. Also, recent developments and field applications of key technology for automatic meter reading associated with smart water meters were analyzed. Smart water meters have been manufactured mostly in United States and Europe and have been expanded their business to Asia. Integrated water management system combining with the additional functions such as real-time consumption metering, cost notification, water conservation, leak detection, water quality monitoring, and flow control have been operated in automatic meter reading. Both water quality and quantity data measured from smart water meters and sensors were transferred to data concentration units through neighborhood area network, and then were transferred to integrated server through wide area network. The data transfer methods were determined by comprehensively considering urban scale, density of smart water meters, power supply and network topologies. Common data collection methods such as fixed network to data concentation units, vehicles drive by, people walk by, and drone fly by have been applied. The automatic meter reading associated with smart water meters are spread throughout the world, and both water and energy savings result in saving the money and reducing the greenhouse gases emission.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.10-10
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• 2008

Silicide is inevitable for CMOSFETs to reduce RC delay by reducing the sheet resistance of gate and source/drain regions. Ni-silicide is a promising material which can be used for the 65nm CMOS technologies. Ni-silicide was proposed in order to make up for the weak points of Co-silicide and Ti-silicide, such as the high consumption of silicon and the line width limitation. Low resistivity NiSi can be formed at low temperature ($\sim500^{\circ}C$) with only one-step heat treat. Ni silicide also has less dependence of sheet resistance on line width and less consumption of silicon because of low resistivity NiSi phase. However, the low thermal stability of the Ni-silicide is a major problem for the post process implementation, such as metalization or ILD(inter layer dielectric) process, that is, it is crucial to prevent both the agglomeration of mono-silicide and its transformation into $NiSi_2$. To solve the thermal immune problem of Ni-silicide, various studies, such as capping layer and inter layer, have been worked. In this paper, the Ni-silicide utilizing Pd stacked layer (Pd/Ni/TiN) was studied for highly thermal immune nano-scale CMOSFETs technology. The proposed structure was compared with NiITiN structure and showed much better thermal stability than Ni/TiN.

• Journal of the Korea Concrete Institute
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• v.28 no.3
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• pp.317-328
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• 2016

This research intends to understand the impact of super-absorbent polymer (SAP) as an internal curing agent in Ultra-High Performance Concrete (UHPC). Two different types of SAPs of acrylic acid (SAP_AA) and acrylic acid-co-acrylamide (SAP_AM) were examined with UHPC formulation. Isothermal calorimetry and x-ray diffraction experiments revealed the impact of polymers with the different chemical bonds on cement hydration. To test its feasibility as a shrinkage reducing admixture for UHPC, a series of experiments including flowability, compressive strength, rapid chloride permeability and autogenous shrinkage profile was performed. While both SAPs showed a reduction in autogenous shrinkage, it has been concluded that the SAP size and chemical form significantly affect the performance as an internal curing agent in UHPC by controlling cement hydration and porosity modification. Between the tested SAPs, SAP_AM which absorbs more water in UHPC than SAP_AA, shows better mechanical and durability performance.

• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.797-807
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• 2008

For this study, the semi-adiabatic temperature rising test is accomplished by using ternary system cement (OPC, BFS, FA) reducing temperature crack. Two tests are conducted; one is for the paste test, and the other is for the concrete test. As the results of paste tests, using fly ash is better to reduce hydration temperature than doing blast furnace slag. In the case of the paste mixed ternary system cement, the more fly ash is mixed and the less blast furnace slag is used, the lower the temperature is. The less the mixture ratio of blast furnace slag is and the more the mixture ratio of fly ash is, the later the temperature rising velocity and descending velocity are. Besides, the temperature is lower if water/binder ratio is high. The use of ternary system cement has the retardation effect of temperature rising because the time to reach the maximum temperature is in the order of OPC100, binary system cement, and ternary system cement. From the test, the maximum temperature of concrete used ternary system cement is $8{\sim}11^{\circ}C$ lower than that of concrete used OPC100. Moreover, temperatures rising velocity and descending velocity of ternary system cement range $47{\sim}51%$ and $37{\sim}42%$ compared with OPC100. The specimen of concrete shows remarkable low internal temperature and slow temperature rising velocity and descending velocity compared with the specimen of paste because it is that temperature loss of concrete is much more than paste specimen according to aggregates.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.79-89
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• 2001

Anaerobic Digestion - Thermophilic Oxic Process(ADTOP) has been known to be one way reducing and composting of organic wastes without draining or forming excess sludge. It could be completely performed by the evaporation of water using the bio-energy from the microbial degradation of organic. In the present study the complete treatment of Chinese restaurant wastes was conducted and utility of bio-energy produced from the ADTOP was estimated. Base on results, it could be concluded as follows; 1) chinese restaurant wastes could be completely treated using the TOP without draining or excess sludge. Maximum volumetric loading rate was determined as $55.0kg-garbage/m^3$. Input water was almostly evaporated and 90.5% of carboneous organic wastes was conversed to carbondioxide. 2)The optimum volumetric loading rate which is acceptable to maintain over $55^{\circ}C$ in the anaerobic digester was determined as $45kg-garbage/m^3{\cdot}d$. 3) The optimum HRT was at least over 10 days in order to maintain about $50^{\circ}C$ in the anaerobic digester using bio-energy produced from TOP. Therefore the utilization of bio-energy produced from TOP could be used in the process which had long HRT such as the anaerobic digestion. 4) The efficiency of anaerobic digester rate were over 90% by the ADTOP under the organic loading rate of $1.1kg-COD/m^3{\cdot}d$, 50kg-Chinese restaurant garbage and $250{\ell}/m^3{\cdot}min$ of the aeration rate.

• International Journal of Highway Engineering
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• v.17 no.3
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• pp.49-58
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• 2015

PURPOSES : The use of environmentally friendly construction methods has been recently encouraged to reduce fuel consumption and the effects of global warming. For this purpose, the roller compacted concrete pavement (RCCP) construction method has been developed. RCCP is more environmentally friendly and economically efficient than general concrete by reducing the amount of CO2 generated through the application of a smaller amount of cement. RCCP has a number of advantages such as an easy construction method, low cost, high structural hydration performance, and aggregate interlocking. However, mix design standards and construction guidelines of RCCP are required for domestic application. In addition, a study on aggregate selection, which has an effect on the characteristics of RCCP, is necessary owing to a limited number of researches. Thus, the aggregate effect on the performance of RCCP in securing the required strength and workability was evaluated in consideration of domestic construction. METHODS : Sand and coarse aggregates of both 19mm and 13mm in maximum size were used in this study. Four types of aggregate gradations (s/a = 30%, 58%, and 70% for the sand and coarse aggregate of 19mm in maximum size, and s/a = 50% for a combination of the three types of aggregates) were set up to investigate the effects of the PCA band on the RCC characteristics. The conditions of s/a = 30% and 70% were evaluated to check the gradation effect outside of the recommended band. The conditions of s/a = 58% and 50% were used because they are the optimum combination of the two and three types of aggregates, respectively. RCCP gradation band was suggested gradation with a proper construction method of RCCP by synthetically comparing and analyzing the correlation of optimum water content, maximum dry density, and strength of requirements through its consistency and compaction test. RESULTS : The lower and upper limit lines are insufficient to secure a relatively strong development and workability compared to an aggregate gradation in the RCCP gradation band region. On the other hand, the line in the RCCP gradation band and the 0.45 power curve in the RCCP gradation band region were satisfactory, ensuring the required strength and workability. CONCLUSIONS : The suitable aggregate gradation on RCCP process should meet the RCCP gradation band area; however, fine particles passing through a #60 sieve do not need to be within the recommended gradation band because the influence of this region on such fine particles is small.

• Food Science and Preservation
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• v.22 no.3
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• pp.314-321
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• 2015

This study was conducted to investigate the quality and characteristics of semi-dried persimmons soaked in different concentrations of sugar solution and stored at $7^{\circ}C$ for 20 days. The L value and chroma value were significantly higher in S5 and S10 compared to the other concentrations of sugar solution. The ${\Delta}E$ and browning degree were increased according to the increase in concentration of sugar solution. Total sugar, reducing sugar, and sugar free contents were higher in the control (semi-dried persimmon) than those in S0, but they increased according to the increase in concentration of sugar solution. Polyphenol oxidase and peroxidase activities were decreased according to the increase in sugar solution concentration, which were highest in S0 among other semi-dried persimmons soaked in sugar solutions. Total ascorbic acid content was highest in S10 (12.29 mg/g), followed by S0 (2.54 mg/g), S5 (7.76 mg/g), S15 (6.05 mg/g), and S20 (5.05 mg/g). Total polyphenols, flavonoids and proanthocyanidins contents were the highest in S10 compared to other semi-dried persimmons soaked in sugar solutions. Furthermore, the same tendency was observed with DPPH radical scavenging ability. These results showed that 10% sugar solution could be applied to semi-dried persimmons in order to achieve high quality, nutritional value, and browning inhibition.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.2
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• pp.185-192
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• 2010

The objective of this study was to investigate the effectiveness of stabilization for army firing range soil highly contaminated with Pb (total Pb: 29,000 mg/kg) using calcined waste oyster shells. The calcination was conducted to activate quicklime from calcite. In order to evaluate the effectiveness of calcination, both natural oyster shells (NOS) and calcined oyster shells (COS) were applied to the Pb contaminated soil. Stabilization was conducted by mixing the contaminated soil with oyster shell media at 5-20 wt% and cured for 28 days. Following 28 days of curing, Pb leachability was measured based on the Korean Standard Test method (0.1 N HCl extraction). The treatment results showed that the COS treatment outperformed the NOS treatment. All of the NOS treatments failed to meet the Korean warning standard of 100 mg/kg. However, the Pb concentrations were significantly reduced to 47 mg/kg and 3 mg/kg upon 15 wt% and 20 wt% COS treatments, respectively which passed the Korean warning standard. Moreover, -#20 mesh materials were more effective than the -#10 mesh materials in effectively reducing Pb leachability. The scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) results indicated that Pb immobilization was strongly linked to Al and Si.

• Journal of the Korea Society for Simulation
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• v.24 no.1
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• pp.35-43
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• 2015

This research proposed a new method to evaluate the objective validity to launch smart transportation services that various stakeholders are complicatedly inter-connected. First of all, we have designed the fundamental business model to form the smart transportation services and defined the stakeholders taking part in the services. Also, the criteria to evaluate the economical validity has been proposed based on the relationship among stakeholders. Especially, in the case EV drivers and charging service providers, the economical validity depends on the scale of spreading. Therefore, we have compared the two extreme scenarios, the poor and stable level of EV spreading. According to the result, it may be said that EV drivers and charging service providers cannot be guaranteed the economical validity due to the burden of initial investment. On the contrary to this, suppliers of EV and charging gears may secure more than a certain level of profit. In addition, the government may have great profit due to reducing the CO2 emission and cost for importing energy sources. Therefore, it is needed to enhance the level of supporting EV drivers and charging service providers at the first stage. Also, the impact of the ratio of EV and charging service stations on the economical validity of smart transportation should be further investigated.