• Asian-Australasian Journal of Animal Sciences
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• v.28 no.12
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• pp.1767-1773
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• 2015

Effects of water-misting sprays with forced ventilation after transport during summer on meat quality, stress parameters, glycolytic potential and microstructures of muscle in broilers were investigated. A total of 105 mixed-sex Arbor Acres broilers were divided into three treatment groups: i) 45-min transport without rest (T group), ii) 45-min transport with 1-h rest (TR group), iii) 45-min transport with 15-min water-misting sprays with forced ventilation and 45-min rest (TWFR group). The results showed the TWFR group significantly increased (p<0.05) initial muscle pH ($pH_i$) and ultimate pH ($pH_u$) and significantly reduced $L^*$ (p<0.05), drip loss, cook loss, creatine kinase, lactate dehydrogenase activity, plasma glucose content, lactate and glycolytic potential when compared with other groups. Microstructure of the muscle from TWFR group broilers under light microscopy showed smaller intercellular spaces among muscle fibers and bundles compared with T group. In conclusion this study indicated water-misting sprays with forced ventilation after transport could relieve the stress caused by transport under high temperature, which was favorable for the broilers' welfare. Furthermore, water-misting sprays with forced ventilation after transport slowed down the postmortem glycolysis rate and inhibited the occurrence of PSE-like meat in broilers. Although rest after transport could also improve the meat quality, the effect was not as significant as water-misting sprays with forced ventilation after transport.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.1
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• pp.122-142
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• 2012

The importance of rainfed areas and animal agriculture on productivity enhancement and food security for economic rural growth in Asia is discussed in the context of opportunities for increasing potential contribution from them. The extent of the rainfed area of about 223 million hectares and the biophysical attributes are described. They have been variously referred to inter alia as fragile, marginal, dry, waste, problem, threatened, range, less favoured, low potential lands, forests and woodlands, including lowlands and uplands. Of these, the terms less favoured areas (LFAs), and low or high potential are quite widely used. The LFAs are characterised by four key features: i) very variable biophysical elements, notably poor soil quality, rainfall, length of growing season and dry periods, ii) extreme poverty and very poor people who continuously face hunger and vulnerability, iii) presence of large populations of ruminant animals (buffaloes, cattle, goats and sheep), and iv) have had minimum development attention and an unfinished wanting agenda. The rainfed humid/sub-humid areas found mainly in South East Asia (99 million ha), and arid/semi-arid tropical systems found in South Asia (116 million ha) are priority agro-ecological zones (AEZs). In India for example, the ecosystem occupies 68% of the total cultivated area and supports 40% of the human and 65% of the livestock populations. The area also produces 4% of food requirements. The biophysical and typical household characteristics, agricultural diversification, patterns of mixed farming and cropping systems are also described. Concerning animals, their role and economic importance, relevance of ownership, nomadic movements, and more importantly their potential value as the entry point for the development of LFAs is discussed. Two examples of demonstrated success concern increasing buffalo production for milk and their expanded use in semi-arid AEZs in India, and the integration of cattle and goats with oil palm in Malaysia. Revitalised development of the LFAs is justified by the demand for agricultural land to meet human needs e.g. housing, recreation and industrialisation; use of arable land to expand crop production to ceiling levels; increasing and very high animal densities; increased urbanisation and pressure on the use of available land; growing environmental concerns of very intensive crop production e.g. acidification and salinisation with rice cultivation; and human health risks due to expanding peri-urban poultry and pig production. The strategies for promoting productivity growth will require concerted R and D on improved use of LFAs, application of systems perspectives for technology delivery, increased investments, a policy framework and improved farmer-researcher-extension linkages. These challenges and their resolution in rainfed areas can forcefully impact on increased productivity, improved livelihoods and human welfare, and environmental sustainability in the future.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.1
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• pp.15-25
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• 2020

Biogas production potential was experimentally estimated for mono- and co-digestion of cow manure and waste grass. The two organic wastes were mixed at five different ratios (100:0, 75:25, 50:50, 25:75, 0:100) on the volatile solids basis, and were assessed using biochemical methane potential (BMP) test. Thee reaction temperatures, 25℃, 30℃ and 35℃, were applied as well, resulting in 15 different combinations for the test. The results showed that both higher temperature and waste grass mixing ratio resulted in higher methane yield and maximum methane production rate. Based on the experimental results, a theoretical farm- or community-scale (240 or 2400 ㎥) anaerobic digester was designed to evaluate the energy balance associated with mono- and co-digestion of the wastes at different temperatures. Although the energy production increased as the temperature and the waste grass mixing ratio increased, the net energy gain, energy production subtracted by energy consumption for heating and maintenance, was estimated to be the highest at 30℃, followed by at 35℃ and 25℃. Therefore, it is advised that both the experimental methane production and the detailed design parameters must be considered for the optimization of the net energy gain from these wastes.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.1
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• pp.1-12
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• 2016

When utilizing a Tunnel Boring Machine (TBM) for tunnelling work, unexpected ground conditions can be encountered that are not predicted in the design stage. These include fractured zones or mixed ground conditions that are likely to reduce the stability of TBM excavation, and result in considerable economic losses such as construction delays or increases in costs. Minimizing these potential risks during tunnel construction is therefore a crucial issue in any mechanized tunneling project. This paper proposed the potential risk events that may occur due to risky ground conditions. A resistivity survey is utilized to predict the risky ground conditions ahead of the tunnel face during construction. The potential risk events are then evaluated based on their occurrence probability and impact. A TBM risk management system that can suggest proper solution methods (measures) for potential risk events is also developed. Multi-Criterion Decision Making (MCDM) is utilized to determine the optimal solution method (optimal measure) to handle risk events. Lastly, an actual construction site, at which there was a risk event during Earth Pressure-Balance (EPB) Shield TBM construction, is analyzed to verify the efficacy of the proposed system.

• The Korean Journal of Physiology
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• v.14 no.2
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• pp.7-16
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• 1980

The effects of various inotropic interventions on the shape of the steady state length tension relation and the length-dependent activation process in cardiac muscle were studied. The influence of inotropic interventions upon the action potential was also observed. The range of varying muscle length was from the optimal length$(l_{max})$, where the active tension production is maximal, to 0.85 $l_{max}$. Changes in stimulus frequency or in external bathing Ca concentration constituted the inotropic interventions in this experiment. The papillary muscles were isolated from the rabbit right ventricles and perfused with $HCO-_3\;-buffered$ normal Tyrode solution which was aerated with $3%\;CO_2-97%\;O_2$ mixed gas and kept at $35^{\circ}C$. Resting Passive tension at $l_{max}$ was approximately 30% of the total tension and appeared from the muscle length of 0.90 $l_{max}$. The effect of stimulus frequency on the steady state level of developed tension was: As the stimulus frequency was increased from 0.1 to 0.5 Hz, there was little change in developed tension. As the frequency was increased further, to a value of about 3 Hz, tension increased steeply. Further increase of the frequency to 5 Hz had little additional effect on the developed tension. The length-tension curves for isometric peak tension became more steeper with the degree of potentiation by inotropic interventions. The relative steepness of the normalized length-tension curves where tension production was expressed as a percentage of maximal tension developed at $l_{max}$, varied inversely with the level of inotropic state and these curves were not superimposable one another. Thus at the stimulus frequency of 2 Hz or at the external Ca concentration of 8 mM, the relative decline in the developed tension for a given change in muscle length was considerably less than the decline observed at the frequency of 0.5 Hz or at the concentration of 2 mM Ca. Action potential duration was prolonged significantly as the frequency increased from 0.2 to 2 Hz, and this change in action potential duration was not observable on the changes in muscle length. There was a tendency of the hyperpolarization of membrane potential when the muscle length was shortened from $l_{max}$ to 0.95 $l_{max}$. These results support the hypothesis that there is a length-dependence of the activation process.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.495-500
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• 2007

Recently we are interest in organic farming of rice. The technology of paper mulching was practised without herbicide in machine transplanting cultivation of paddy. A field experiment was conducted in Gangseo series (coarse loamy, mixed, nonacid, mesic family of Aquic Fluventic Eutrochrepts) at the National Institute of Crop Science (NICS), RDA, Suwon, Gyeonggi province, Republic of Korea in 2004. This experiment was carried out to evaluate soil redox potential, weed control and rice growth by the different organic matter in paper mulching transplanting. Compost, rice straw and soiling rye were incorporated as organic matter. The nitrogen amount of controlled-release fertilizer (CRF) plot was 80% compared with nitrogen amount ($110kg\;ha^{-1}$) of conventional fertilization. Mulching paper consisted of recycled paper which was coated with biodegradable plastics. There were no difference between conventional rice transplanting and paper mulching on missing hills after organic matter application. Weed control were the highest at added soiling rye plot. The redox potential of soil was the lowest in rice straw + CRF 80% plot at tillering stage. The $NH_4{^+}-N$ in soil was the highest at soiling rye + CRF 80% tillering stage. There was no difference in yield between soiling rye + CRF 80%, compost + CRF 80% and conventional fertilization plot.

• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.40-49
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• 2018

We evaluated the antioxidant activity and neuronal cell-protective effect of fucoidan extract from Ecklonia cava (FEC) on hydrogen peroxide ($H_2O_2$)-induced cytotoxicity in PC-12 and MC-IXC cells to assess its protective effect against oxidative stress. Antioxidant activities were examined using the ABTS radical scavenging activity and malondialdehyde-inhibitory effect, and the results showed that FEC had significant antioxidant activity. Intracellular ROS contents and neuronal cell viability were investigated using the DCF-DA assay and MTT reduction assay. FEC also showed remarkable neuronal cell-protective effect compared with vitamin C as a positive control for both $H_2O_2$-treated PC-12 and MC-IXC cells. Based on the neuronal cell-protective effects, mitochondrial function was analyzed in PC-12 cells, and FEC significantly restored mitochondrial damage by increasing the mitochondrial membrane potential (${\Delta}{\Psi}m$) and ATP levels and regulating mitochondrial-mediated proteins (p-AMPK and BAX). Finally, the inhibitory effects against acetylcholinesterase (AChE), which is a critical hydrolyzing enzyme of the neurotransmitter acetylcholine in the cholinergic system, were investigated ($IC_{50}$ value = 1.3 mg/ml) and showed a mixed (competitive and noncompetitive) pattern of inhibition. Our findings suggest that FEC may be used as a potential material for alleviating oxidative stress-induced neuronal damage by regulating mitochondrial function and AChE inhibition.

• Applied Chemistry for Engineering
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• v.27 no.4
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• pp.386-390
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• 2016

The surface of carbon nanotubes (CNTs) was modified by fluorination and applied to conductive materials to improve the energy efficiency of a capacitive desalination (CDI) electrode. CNTs were fluorinated at room temperature with a mixed gas of fluorine and nitrogen, and activated carbon based CDI electrodes were then prepared by adding 0-0.5 wt% of untreated CNTs or fluorinated CNTs with respect to the activated carbon. Fluorinated CNTs showed improved dispersibility in the electrode and also slurry as compared to untreated CNTs, which was confirmed by the zeta potential and scanning electron microscopy. Fluorinated CNTs added electrodes showed higher desalination efficiency but lower energy consumption than those of using untreated CNTs added electrodes. This was attributed to the decrease in the resistance of CDI electrodes due to the improved dispersibility of CNTs by fluorination.

• Journal of the Korea Institute of Building Construction
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• v.19 no.6
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• pp.511-520
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• 2019

The critical chloride content of rebar embedded in concrete was experimentally evaluated according to the admixture replacement ratio and admixture type. Four types of reinforced concrete were mixed OPC 100%, OPC 70% + GGBFS 30%, OPC 40% + GGBFS 60%, and OPC 40% + GGBFS 40% + FA 20%. NaCl solution was supplied to the specimens, and the open circuit potential of the embedded rebar was monitored. The specimens determined to initiate corrosion were cut at intervals of 5mm from the NaCl solution supply surface and conducted to chlorine ion profile. Corrosion initiation time of rebar embedded in concrete was delayed as the admixture replacement ratio increased. Looking at the critical chloride content of the types of reinforced concrete, it was highest in OPC 1.46kg/㎥, followed in order by S30 0.98kg/㎥, TBC 0.74kg/㎥, and S60 0.71kg/㎥.

• Strategy21
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• s.39
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• pp.163-197
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• 2016

The completion of Jeju Naval Base on February 2016 made the Republic of Korea Navy(ROKN) review the size and role of the Maritime Task Flotilla(MTF). The new strategic environment for the 12st century and the new challenges require the Navy to counter North Korea's provocations and prevent potential enemy's threat. The Navy is also required to take part in the variety of international roles and missions commensurated with Korea's global status to maximize the national interest. Despite these changes, Korea's military construction concept is still unable to break away from the old paradigm of the North Korean threat largely centered. In order to develop the current MTF into the Task Group with the construction of Jeju Naval Base, the Navy must newly not only establish new force development plan and fleet management concepts but also go to persuade and convince policy decision makers. To this end, the following efforts should be promoted. First, the ROK Navy steps up efforts in order to share with the Task Group's vision and strategy. The Navy should also provide the size and structure as well as the missions and roles of the Task Group to react to new maritime security environment. Second, the Navy analyse the MTF's ability and what is required and necessary to perform its duty. After that, it must set out the direction of the Task Group's force development. Third, the current missions and roles of the MTF should be re-established to respond various threats. Finally, accommodating of new technology to the MTF should intensify its strengths. The ROK Navy has a mixed force structure consisting of three fixed- base fleets and a MTF. The fixed base fleet has a passive force to defend and protect its own sea areas, but the MTF should actively not only counter North Korea's threats, including ballistic missiles, but also fight potential threats and takes international missions as a primary task force. However, the MTF has a limited capability to accomplish given missions and long-range operations, and thus, the ROK Navy is strongly required to construct the Task Group.