• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.345-350
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• 2003

The development of a prototype for a Bridge Transported Servo Manipulator (BTSM) system operating in a hot cell is introduced. Mechanical master-slave manipulators (MSMs) which are mounted on the hot cell wall cannot access all the areas for the equipment maintenance due to their reach limitation. The BTSM has been developed to overcome the limitation of access that is a drawback of the MSMs for the equipment maintenance. Wire driven mechanisms have been adopted to increase the handling capacity to weight. This system can be a useful reference for designing other devices in the nuclear industry.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.10
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• pp.467-473
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• 2014

Since the operating conditions of HVAC systems are different from those for which they are designed, on-going commissioning is required to optimize the energy consumed and the environment in the building. This study presents a methodology to analyze operational data and its applications. A predicted operation model is to be produced through a statistical data analysis using multiple regressions in SPSS. In this model, the dependent variable is the pre-cooling time, and the independent variables include the power output of the supply air inverter during pre-cooling, the supply air set temperature during pre-cooling, the indoor temperature-indoor set temperature just before pre-cooling, supply heat capacity, and the lowest outdoor air temperature during non-cooling/non-heating hours. The correlation coefficient R2 of the multiple regression model between the pre-cooling hour and the internal/external factors is of 0.612, and this could be used to provide information related to energy conservation and operating guidance.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.10
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• pp.687-696
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• 2010

In this study, FDD algorithm was developed using the normalized distance method and general pattern classifier method that can be applied to constant air volume air handling unit(CAV AHU) system. The simulation model using TRNSYS and EES was developed in order to obtain characteristic data of CAV AHU system under the normal and the faulty operation. Sensitivity analysis of fault detection was carried out with respect to fault progress. When differential pressure of mixed air filter increased by more than about 105 pascal, FDD algorithm was able to detect the fault. The return air temperature is very important measurement parameter controlling cooling capacity. Therefore, it is important to detect measurement error of the return air temperature. Measurement error of the return air temperature sensor can be detected at below $1.2^{\circ}C$ by FDD algorithm. FDD algorithm developed in this study was found to indicate each failure modes accurately.

• Nuclear Engineering and Technology
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• v.21 no.3
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• pp.186-192
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• 1989

As a part of the design of the top end piece(TEP) for the 14$\times$14 reload fuel, various models of top end piece structure were analysed, using the ANSYS code, under fuel assembly shipping and handling load conditions. The 3-dimensional isoparametric elements were used in each model. By rearrangement of slots and holes on the adapter plate, without violating the design requirements, and also by changing the enclosure attachment method used on the adapter plate from pin joints to through-weld, the load carving capacity of the adapter plate was greatly strengthened. These concepts were adopted for the design of the 14$\times$14 reload fuel.

• Proceedings of the ESK Conference
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• 1997.10a
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• pp.286-294
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• 1997

The objective of this study was to make comparison of the physical work capacities(PWCs) for three different types of tasks. For this purpose, an ergometer exercise, a treadmill exercise, and lifting activities with four different frequencies (2, 5, 8, 11 lifts/min) for the lifting range from floor to 76cm were considered. Oxygen consumption rates and heart rates were measured during the exercises and lifting activities. The PWC values for ergometer exercise test was 2562.71 ml-O$_{2}$/min and the one for treadmill exercise was 2874.89 ml-0$_{2}$/min. The value of lifting PWC increased from 1774.07ml-0$_{2}$/min to 2296.76 ml-0$_{2}$/min as the lifting frequency increased from 2 to 11 lifts/min. The ratio of the lifting PWCs to the ergometer PWCs increased from 69.36% to 89.77% as the lifting frequency increased. To the treadmill PWCs, the ratio increased from 62.21% to 85.24% as the lifting frequency increased. From this result, it is appears that the PWCs based on the lifting tasks rather than PWCs by ergometer or treadmill exercise should be considered to determine the physiological criterion for safe weights for lifting tasks. Therefore, the physiological criteria of the NIOSH Guideline should be reexamined.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.10
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• pp.1051-1058
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• 2011

Unmanned autonomous forklifts have a great potential to enhance the productivity of material handling in various applications because these forklifts can pick up and deliver loads without an operator and any fixed guide. Especially, automation of pallet loading and unloading technique is useful for enhancing performance of logistics and reducing cost for automation system. There are, however, many technical difficulties in developing such forklifts including localization, map building, sensor fusion, control, and so on. This is because the system requires numerous sensors, actuators, and controllers that need to be connected with each other, and the number of connections grows very rapidly as the number of devices grows. This paper presents a vision sensorbased autonomous loading and unloading for network-based unmanned forklift where system components are connected to a shared CAN network. Functions such as image processing and control algorithm are divided into small tasks that are distributed over a number of microcontrollers with a limited computing capacity. And the experimental results show that proposed architecture can be an appropriate choice for autonomous loading in the unmanned forklift.

• Computers and Concrete
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• v.22 no.2
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• pp.197-207
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• 2018

In the present study, group method of data handling networks (GMDH) are adopted and evaluated for shear strength prediction of both FRP-reinforced concrete members with and without stirrups. Input parameters considered for the GMDH are altogether 12 influential geometrical and mechanical parameters. Two available and very recently collected comprehensive datasets containing 112 and 175 data samples are used to develop new models for two cases with and without shear reinforcement, respectively. The proposed GMDH models are compared with several codes of practice. An artificial neural network (ANN) model and an ANFIS based model are also developed using the same databases to further assessment of GMDH. The accuracy of the developed models is evaluated by statistical error parameters. The results show that the GMDH outperforms other models and successfully can be used as a practical and effective tool for shear strength prediction of members without stirrups ($R^2=0.94$) and with stirrups ($R^2=0.95$). Furthermore, the relative importance and influence of input parameters in the prediction of shear capacity of reinforced concrete members are evaluated through parametric and sensitivity analyses.

• Journal of the Korean Institute of Telematics and Electronics
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• v.12 no.5
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• pp.12-18
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• 1975

Triac phase controlled pre-regulator를 이용한 직류안정화전원에서 제어소자 전력소모를 촤소로 줄이기 위하여, 부하전류의 증가에 따라 제어소자 양단전압을 낮추어 주는 회로를 고안하여 부가하였다. 이렇게 하므로써 제어소자의 전력소모가 약 40%정도 감소되어 방열장치가 간단해지거나 전력용량을 증가할 수 있게 되었으며 열발산이 곤란한 monolithic I.C.화에 유용하도록 하였다. A method on minimizing the power dissipation in the control element of a series D.C. voltage regutator is devised. An additional control circuit which reduces the average voltage drop across the control element according to increasing the load current is attached :o the trial phase controlled pre-regulator system. It is verified that the power dissipation in the control element is reduced up to 40% by this. circuit arrangement. The heat sink system can be simplified and the capacity of tile handling power is also increased. It is expected that this circuit arrangement can be applied to I.C. fabrication.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.12
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• pp.799-804
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• 2011

Radioactivity of high concentrations have existed in the handling nuclear materials in hot cell of PIEF(Post Irradiation Examination Facility). The exhaust filtration system was enabled to process cylindrical filters by using a manipulator in the hot cell. By establishing a double filtration system with two filters, backup protection against leakage or failure of the first is provided by the second filter. Additionally, this a arrangement is arrange intended to increase the total filtration efficiency. The result of the pressure drop changing in the air flow of the cylindrical and HEPA filters is observed by a curved line. A filtering efficiency of more than 99.99% to $0.3{\mu}m$ particle appears in the upstream and downstream during the efficiency test on the HEPA filters. The V-pleats type had a lower pressure drop than the separator type. There was no damage during usage and was found to be suitable with high capacity of air volume. Therefore, by carrying out performance tests of the exhaust filtration system, efficiency and safety can be achieved.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.15 no.4
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• pp.341-352
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• 1990

In this paper, we introduce tree types of switching networks, I, e., a fully segregated type, a partially integrated type, and a fully integrated type switch, to accommodate nx 64Kb/s multi-slot connection traffic and analyze their blocking probabilites for the different traffic mixes by utilizing a computational algorithm of blocking probability, and finally determine the traffic handling capacity which satisfies the given grade of service. The fully integrated type switch can accommodate the ISDN traffic with relatively low wideband traffic. However, either the partially integrated type or the fully segregated type switch is needed to accommodate the ISDN traffic as the wideband traffic increases. This result can be usilized in the design of ISDN switching networks accommodating multi-slot connection traffic.