In this research, it is studied whether an abandoned tunnel can be used for a warehouse to keep rice. Today's agricultural industry especially rice farming in our nation is put in the bad condition such as not sufficient man power, not enough capital and so on, and moreover dose not have competitive power as well-known against products from other nations through FTA. But there are many ways to increase competitive power we can guess. Development of technique to keep quality of the agricultural product by controlled atmosphere is one of the reasonable ways.
From these backgrounds, it has been studied whether an abandoned tunnel is suitable for rice as storage place or not. In the result, the inner condition of the abandoned tunnel was measured that temperature is 15℃ in average and relative humidity is 55% in average and it is therefore found that to use an abandoned tunnel as a place to storage rice is reasonable in the consideration of thermal and cost-saving aspect.
Recently, ice-on-coil type ice storage system has become a very popular issue in application to electric powered air conditioning systems. An experimental study has been carried out to investigate the ice making characteristics of an ice-on-coil type ice storage system. The ice storage system used two rectangular tank, one is 900 ℓ with a thermal capacity 3,300 kcal/h and the other is 3,000 ℓ with a thermal capacity 9,900 kcal/h. An experimental data has been measured as the variation of a ice making time. The results indicate that the ice making rate increase due to variation of ice making time gradually, and is high in case of the smaller refrigerant coil from 5 hour but larger refrigerant coil after this.
The Automobiles with a combustion engine use a transmission for increasing drive force, reverse-move and maintaining non-load condition in general. In the Electric automobile system, output-axial can be operated just by controlling the motor manipulated with power. It also does not need reverse-gear by rotating the motor in the opposite direction. Designed to assemble two different types of planetary gear ratio and to be input torque of input-axial in sun gear and divide ring gear Ⅰ, Ⅱ and then after one of ring gear is fixed, in accordance with the planetary gear velocity ratio, the first gear has 0.136 decreased speed and second gear has 0.240 decreased speed, separately. While the planetary gear type transmission showed over the 92% of efficiency in the all of velocity range. The transmission proposed in this study can be expected to apply to the electric vehicle or others.
A study of fuelcell hybrid electronic vehicle for improve fuel consumption is used one wheel dynamic vehicle model and make a profound study of control strategy for cuts fuel consumption. For this reason there is a limit to study of real vehicle fuel consumption increase with weight transfer. This study perform a precision multi-body fuelcell hybrid electronic vehicle modeling using functional suspension model have fast analysis time. Verify a improve fuel consumption in urban driving cycle compare with one wheel dynamic model and demonstrate a power loss decrease by weight transfer is causes of fuel consumption rise.
The Heat Transport system loop stability of CANDU-6 reactor as Wolsong-1 with the CANFLEX fuel bundle has been studied. The SOPHT modelling of the CANFLEX fuel bundle and the ROH interconnection line was made and the stability analysis response of Wolsong-1 reactor with CANFLEX fuel bundle was obtained. The mechanics of the flow instability caused by two phase flow was reviewed. Without the ROH interconnection line the Heat Transport system loop is unstable while the Heat Transport system is stable within ±1 % of nominal flow with the ROH interconnection line
asically, a current sensor is consisted of ferromagnetic core, coil and magnetic sensor. To measure alternative current, 2 methods are existed. The first method is measurement of the induced elect개motive force of coil, which is wired in ferromagnetic core. The second measurement method is utilized with the magnetic sensor, such as hall effect sensor. However, those methods have some problem. This paper introduces the development of direct current sensor using magnetostriction. Principally, magnetostriction is the phenomenon of expansion of contraction when ferromagnetic core is placed in an alternating magnetic field. This induced electromagnetic induction and the direct current can be measured such as measurement of alternating current.
An active suspension system has an external energy source, from which energy is constantly supplied to the system for continuous control of the vehicle's motion. There are some control strategies. In the study, the reduced-order active suspension control strategy via the singular perturbation technique is applied to the half car model which has 4 DOF. The performance of the hydraulic active suspension system utilizing this control strategy is investigated and compared with those of the systems with the full-order state feedback control and the sky-hook damping control. Their performances are compared through the computer simulation in the time and the frequency responses, respectively. In the transient response analysis, the C-language program is used, and Matlab program tool is used in the frequency response analysis. It is shown that the reduced-order control strategy yields almost the same performance as that of the full-order state feedback control, and gives better performance than that of the sky-hook damping control, especially in ride quality.
This study presents the method of design and manufacturing of aspheric lens for flow visualization. Spherical lens is used in many fields especially flow visualization experiment. Because sperical lens has aberration by origin in flow visualization, there is case that is alternated by asperic lens. Most of asperic lens's modeling which is applied to Taylor's method. This study is designed to the aspheric lens by Euler's method, which is useful method for various geometric shape and complex experimental apparatus for flow visualization. In the present study, we have verified design and manufacturing aspheric lens through a flow visualization experiment.
In this study, mold does not modify the overall. And core was developed as part of a separate. And not detached from the injection mold core part of the device only has to exchange. It has to perform the simulation of resin flow injection. Result of analysis, problems were observed. To create the change core of the four kinds of production prototypes and replace only with the exchange of change core operation of the injection. As a result, there were able to get a products with smooth surface.
In the case of Inmold injection, it is a device which conducts injection and painting. In order to design it is important composition of devices to accurate feed of film and process of analysis. It used program of plastic injection flow analysis in order to a flow aspect of resin. It might be used shape crystallization of products, design of mold and process of feed device. In the case of inmold injection, film supply equipment is one of important device. 2-dimensional designs and 3-dimensional modelings are performed for its manufacturing. Specially 3-dimensional modeling data is used in structural strength analysis by finite element method. These background data is avail of manufacture of film supply equipment. Finally it is performed mold injection test and we got the satisfactory result.
Heat transfer enhancement of fin-tube heat exchangers with vortex generators is investigated using naphthalene sublimation technique. Experiments are performed for the fin-flat tube and the fin-circular tube heat exchangers with and without vortex generator. Vortex generators are found to enhance heat transfer rate on the fin surface dramatically. Their effect is relatively high in the fin-flat tube heat exchanger compared to fin-circular tube heat exchanger. Performance test is done for the prototype of air-conditioning heat exchanger and gas boiler heat exchanger with and without vortex generators .Fin-flat tube heat exchanger with vortex generator promote local heat transfer coefficient by 75% and increase friction factor, but friction of fin-flat tube heat exchanger with vortex generator is lower than that of fin-circular tube heat exchanger without vortex generator by 45%
The numerical calculation was carried out using OmniCADDⓇ HCS Hydraulic Calculation Software to certify if flow velocities in pipes reduced in diameter were satisfied with fire codes for a dry system of underground parking area in apartment complex. The design pressure and flow rate for the dry system were 4.3 bar and 1633.8 lpm. The maximum discharge pressure and flow rate of sprinklers were 2.2 bar and 118.2 lpm. The maximum flow velocities in main pipe, branch line and other pipe of the dry system were 1.5 m/s, 5.0 m/s and 3.5 m/s. The design propriety could be clearly certified by satisfying with fire codes related to flow velocities for the pipe network of the dry system.
Polymer gel implant for soft tissue augment is demanded biological safety properties. This study is designed process and equipment producing for obtain micro bead using the hyaluronic acid water solution. This equipment is composed of cooling pipe, air pump, dispenser and process is consecutive/simple for preservation from environmental contamination. Besides, without difficulty remove the residual agent after crosslink. We evaluate to in vitro cytotoxicity test for verification of hyaluronic acid gel obtained by this equipment and process. This product is "non cytotoxcity" from the result of evaluation cytotoxcity test.
Energy saving and decreasing green gas are critical issue today, so various technologies to save energy and decrease carbon dioxide in plant process have been applied to many industrial area. In this paper, the feasibility of condenser heat recovery in power plant was reviewed by verifying 에너지 평형 and simulating power plant model. Some ways to compose proper system and their possibilities were also reviewed. The amount of heating recovery and changed heating capacity were verified by simulation. There is noticeable improvement of plant performance in simulated result. Future study and experiment will show more evident results.
Recently, Clinical reports about reducing the delivery time, pain, instrument delivery, and C-section by increasing intrauterine pressure through giving a steady pressure on fundus have been released. However, the use of fundal pressure during the labor is a cause of great concern about medical malpractice and accidents caused by overpressure on fundus. To practice fundal pressure in safe way, medical device is designed. The device consists of inflatable belt, controller, and TOCO transducer; it inflates the belt to give air pressure onto fundus. In this study, we propose the shape of belt to give an air pressure on fundus equally, efficiently, and safely.