• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.603-609
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• 2001

A transport stress is one of the main causes of economic losses and physiological dysfunction. The present study has been performed to suggest a method to decrease the adverse effects above mentioned from transport. The groups were prepared as follows; (1) Control group : 4 cattle transported for 5 hrs (274 km) without any treatment, (2) Treatment group : 4 cattle treated with electrolyte-mineral solution (I.V.) at 1 hr before the enrollment of transport under same experimental condition with Control group. The blood specimens were collected at 1 hr before transport, 2.3 hrs (135 km) and 5 hrs (274 km) after the enrollment of transport, and 1, 6 and 18 hrs after fulfillment of transport. The collected blood specimens were analyzed for cortisol and epinephrine. Core temperature and heart rate were measured with active biotelemetry in every 30 minutes from 0.5 hr before the start of transport to 18 hrs after the end of transport. In results, the level of cortisol considerably increased to the peak either in Control group ($5.3{\pm}1.3{\mu}g/d{\ell}$) and in Treatment group ($4.0{\pm}2.6{\mu}g/d{\ell}$) at 2.3 hrs in transport. The concentration of epinephrine of Treatment group had been higher than that of Control group from the start of transport to 18 hrs after the fulfillment of transport. Particularly there was the biggest gap between Control and Treatment groups, $424.0{\pm}194.1pg/m{\ell}$ and $209.1{\pm}65.1pg/m{\ell}$ respectively, at 6 hrs after the end of transport. The heart rates were considerably increased either in Control group ($81.5{\pm}18.5$ to $126.3{\pm}7.8beats/min$) and in Treatment group ($114.3{\pm}14.4$ to $140.8{\pm}22.4beats/min$) with the enrollment of transport. These results indicate that the concentration of cortisol and the heart rate were pertinent to cognitive parameters to evaluate physiological responses against stress such as transport. In addition, the intravenous administration of electrolyte-mineral solution could be suggested as the method to decrease the adverse effects from a transport stress.

• 한국신재생에너지학회:학술대회논문집
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• 2005.11a
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• pp.648-654
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• 2005

The performance prediction of a planar-type solid oxide fuel ceil is conducted by a computational analysis. The transport processes are formulated with the help of a simplified treatment of heat generation by the electrochemical reaction. From the result of the computational analysis, it is shown that the electrochemical reaction is closely related to the transport phenomena inside a solid oxide fuel cell. Transport phenomena including heat and mass transfer have influence on the distribution of local current density and as a result, on the performance characteristics of the fuel cell. Computational analysis is also extended to the parametric study to investigate the performance behavior of the fuel cell with different amount of supplied fuel flow rates. It is also demonstrated that the mathematical formulation and computational procedures proposed in this study can be applied to prove the importance of the specific TPB(Three-Phase-Boundary) area in the manufacturing process of electrodes in a solid oxide fuel cell.

• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.207-214
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• 2001

The KN-12 spent nuclear fuel (SNF) transport cask is designed for transportation of up to 12 assemblies and is in standby status for being licensed in accordance with Korea Atomic Energy Act. To evaluate radiation shielding and criticality safety of the KN-12 cask, each case of study was carried out using MCNP4B Code. MCNP code is verified by performing benchmark calculation for the KSC-4 SNF cask designed in 1989. As a result of radiation safety evaluation for the KN-12 cask, calculated dose rates always satisfied the standards at the cask surface, at 2m from the surface in normal transport condition, and at 1 m from the surface in hypothetical accident condition. Maximum dose rate was always arisen on the side of the cask. For normal transport condition, photons primarily contribute to dose rate between two kinds of released sources, neutrons and photons, from spent nuclear fuel but for hypothetical accident condition, contrary case was resulted. The level of calculated dose rate was 27.8% of the limit at the cask surface, 89.3% at 2 m from the cask surface, and 25.1% at 1 m from the cask surface. For criticality analysis, keff resulting from the criticality analysis considering the condition of optimum partial flooding with fresh water is 0.89708(0.00065. The results confirm the standards recommended by all regulations on radiation safety.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.10 no.4
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• pp.187-196
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• 1998

Morphological changes around the groin system in the beach are examined using a numerical model. The model consists of two parts : the hydrodynamic model which calculates the transformation of waves and currents, and the sediment transport model which determines sediment transport rates and bottom topographic changes. The numerical model is applied to single-groin and three-groin systems on a typical plane beach. The changes to the beach system due to waves and currents during 150-day simulation near the groins are calculated using sediment transport rate patterns in the domain. The sand by-passing rate patterns around groins are also evaluated.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.3
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• pp.138-152
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• 2007

A communication system based on DATEX-ASN, an international communication protocol for use in COSMOS, a real-time traffic responsive signal system of Seoul, was developed in this study. Through laboratory experiments, it was identified that some additional rules were necessary for its successful application to COSMOS and thus proper complementary rules were devised. Laboratory experiments were to measure error-rates of monitoring information packet, EOC duration and operating cycle-length errors at different data transmission rates and the results of each experiment were compared each other. The results show that the DATEX-ASN protocol requires a transmission rate of at least 9,600bps which is higher than a transmission rate of 4,800bps required by NTCIP.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.1
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• pp.66-71
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• 2012

In this paper, using the bargaining game theory, we propose a bandwidth management scheme that allocates bandwidth in an efficient and proportionally fair manner between the service classes with different service requirements. Since the traffic input rates of the classes are asymmetric in most of the time, the proposed scheme allocates bandwidth in proportion to the traffic input rates to increase the bandwidth utilization while protecting the quality of service of a class against the excessive traffic input of the other classes. In addition, the proposed method considers the weights of classes so that the bandwidth is allocated differentially among the classes.

• Journal of Korean Society of Transportation
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• v.31 no.3
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• pp.65-73
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• 2013

Exclusive median bus lanes were installed to mitigate congestions on urban traffic networks. However, capacity analysis of signalized intersections having exclusive median bus lanes have not been provided in current capacity analysis process(analyses). This study aims to develop a method of capacity analysis for lane groups consisting of only buses at the signalized intersections having exclusive median bus lanes. Finding basic saturation flow rates for buses is critical since the operational characteristics between automobiles and buses are fairly different. A total of 8 intersections in Seoul were chosen as study sites. Saturation headways, distances between bus-stop and stopline, and grades of each approach were measured at the sites. It was found that the basic saturation headway and the basic saturation flow rate of buses were 3.27 s/veh and 1,100pc/h/ln, respectively. Adjustment factor for upstream bus-stop locations was estimated with 0.50 and 0.75 when the distances between bus-stop and stopline are 20m and 70m, respectively. This study explains that bus saturation flow rates are decreased in half if the bus stop locates within 20 meters from stop lines.

• Journal of Advanced Navigation Technology
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• v.21 no.1
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• pp.90-98
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• 2017

This paper is concerned with air traffic controllers' fatigue and stress that they experience during their daily job particularly as being shift workers. Previous researches reveal that the controllers' fatigue and stress increase by several factors including time spent at work, traffic intensity, visibility, etc. The researches also indicate that air traffic controllers' fatigue and stress can be reasonably surrogated by their heart rate. We set three hypotheses relating the influencing factors and the fatigue and stress represented by the heart rates. Using wrist bands, air traffic controllers' heart rates at various situations are collected at Choongju airport. The hypothetical tests explicitly confirm that the heart rate is highly correlated with the traffic level and the time spent at work. In particular, it be shown that even when handling the same traffic level, air traffic controllers' stress level increases as the time they spent at work increases.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.4
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• pp.263-272
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• 2012

A GoldSim template program for a safety assessment of a hybrid-typed repository system, called A-KRS, in which two kinds of pyro-processed radioactive wastes, low-level metal wastes and ceramic high-level wastes that arise from the pyro-processing of PWR nuclear spent fuels are disposed of, has been developed. This program is ready both for a deterministic and probabilistic total system performance assessment which is able to evaluate nuclide release from the repository and farther transport into the geosphere and biosphere under various normal, disruptive natural and manmade events, and scenarios. The A-KRS has been probabilistically assessed with 9 selected input parameters, each of which has its own statistical distribution for a normal release and transport scenario associated with nuclide release and transport in and around the repository. Probabilistic dose exposure rates to the farming exposure group have been evaluated. A sensitivity of 9 selected parameters to the result has also been investigated to see which parameter is more sensitive and important to the exposure rates.

• Journal of Korea Trade
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• v.24 no.6
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• pp.115-134
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• 2020

Purpose - International trade leads to the international division of labor, improving the efficiency of the global economic system. Transport costs are a more serious barrier to international trade than customs tariffs. An increase in competition in the transport sector may thus lead to a reduction in transport costs. However, if a carrier's nationality significantly influences transport costs, simply adding more competing carriers of different nationalities would be ineffective. Therefore, it is necessary to establish national or regional carriers to influence competition and reduce transport costs. This study investigates this "nationality effect" by treating Hanjin Shipping's collapse as a natural experiment. Design/methodology - The theoretical basis of this study is the 3rd-degree price discrimination in container shipping market. By using the monthly data of container freight rates of Korea, China and Japan, this study shows the so-called Korea Premiums, which are the empirical counterparts of nationality effect in Korea container shipping market. For this empirical investigation, the structural model with state-space form is used and the dummy models are also estimated. In addition, because China has been also affected by the Hanjin's collapse, the China premiums are considered too. Findings - Compared with Japan's case, it is shown that there had been the so-called Korea premiums since the collapse of Hanjin Shipping. These results are robust from both the state-space model and dummy models. The time pattern of Korea premiums was consistent with the market evolution, especially the pattern of substitutability in container shipping markets. In addition, this paper shows the magnitude of Korea premiums. Originality/value - The argument of this study that the nationality effect can be interpreted as an extended concept of the home market effect is original, which is expected to evoke future research efforts. Further, the discussion on the shipping industrial policy from both horizontal and vertical aspects will provide the relevant policy makers with solid information, especially for the policy coordination in a global scale.