• Korean Journal of Food Science and Technology
• /
• v.21 no.6
• /
• pp.815-819
• /
• 1989

Rheological properties of chestnut starch suspensions (3 and 4%, db) and gelatinized starch (4%, db) were investigated with a capillary and rotational viscometer, respectively. Starch suspensions had no yield stress and showed dilatant flow behavior in the temperature ranges of $30-65^{\circ}C$. However, starch suspension showed pseudoplastic flow behavior at $70^{\circ}C\; and\;above\; 65^{\circ}C$ for 3 and 4% concentration, respectively Flow activation energy below $50^{\circ}C$ was 0.56 kcal/mole but increased to 51.9-80.8 kcal/mole at $60-70^{\circ}C$. The behavior of gelatinized starch (4%) was pseudoplastic regardless of heating temperature $(65-80^{\circ}C)$ and time (15-60 min). The apparent viscosity of the starch remained constant after heating at $80^{\circ}C$ for 45 min. The swelling power and log apparent viscosity showed similar pattern. The activation energy of the apparent viscosity of the geletinized starch at $70-80^{\circ}C$ was 13.09kcal/mole. The apparent viscosity of thermal-gelatinized $(90^{\circ}C)$ starch was lower than that of 15 psi-gelatinized starch.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.28 no.2
• /
• pp.161-164
• /
• 2002

In recent, distraction osteogenesis has been used to correct skeletal malformations and discrepancies in the craniofacial area. It also seems to be considered as an alternative in the treatment of severe midfacial hypoplasia. There are some types of distractors for midfacial distraction such as subcutaneous distractors and rigid external distractors. We used a rigid external distractor for correction (RED) of craniofacial hypoplasia. Seven patients underwent a midfacial distraction osteogenesis with a rigid external distractor between April 2000 and July 2001. Three patients suffered from Apert's syndrome, three patients from Crouzon's syndrome, and one patient suffered from midfacial hypoplasia due to midfacial radiotheraphy during childhood. On average, the mean distance of distraction was 19.8mm ($10{\sim}25mm$) and the distraction lasted for 24 days. The patients showed no severe complications like infections, optic disturbance, or wrong distraction vectors. One patient complained pain on the site of the occipital fixation of the distractor. In one patient who underwent subtotal craniectomy 3 months before Le Fort III distraction, the distractor was dislocated as the cranial bone was too weak to support the distractor. This report reveals that the application of rigid external distractor and transfacial pull results in an exact control of the distraction vectors and an excellent correction of midfacial hypoplasia without any severe complications.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.25 no.2
• /
• pp.171-181
• /
• 2009

The objective of this study was to analyse stress distribution of maxillary complex by use of face mask. The construction of the three-dimensional FEM model was based on the computed tomography(CT) scans of 13.5 years-old male subject. The CT image were digitized and converted to the finite element model by using the mimics program, with PATRAN. An anteriorly directed force of 500g was applied at the first premolar 45 degrees downwards to the FH plane and at the first molar 20 degrees downwards to the FH plane. When 45 degrees force was applied at maxillary first premolar, there were observed expansion at molar part and constriction at premolar part. The largest displacement was 0.00011mm in the x-axis. In the y-axis, anterior displacement observed generally 0.00030mm at maximum. In the z-axis, maxillary complex was displaced 0.00036 mm forward and downward. When 20 degrees force was applied at maxilla first molar, there were observed expansion at lateral nasal wall and constriction at molar part. The largest displacement was 0.001mm in the X-axis. In the Y-axis, anterior displacement observed generally 0.004mm at maximum. In the Z-axis, ANS was displaced upward and pterygoid complex was displaced downward. The largest displacement was 0.002mm.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.24 no.5
• /
• pp.548-553
• /
• 2014

In order to evaluate the performance of arrow that manufactures through production process, it is used that personal experiences such as hunters who have been using bow and arrow for a long time, technicians who produces leisure and sports equipment, and experts related with this industries. Also, the intensity of arrow's impact point which obtains from repeated shooting experiments is an important indicator for evaluating the performance of arrow. There are some ongoing researches for evaluating performance of arrow using intensity of the arrow's impact point and the arrow's flying image that obtained from high-speed camera. However, the research that deals with mutual relation between distribution of the arrow's impact point and characteristics of the arrow (length, weight, spine, overlap, straightness) is not enough. Therefore, this paper suggests both the system that could describes the distribution of the arrow's impact point into numerical representation and the correlation model between characteristics of arrow and impact points. The inputs of the model are characteristics of arrow (spine, straightness). And the output is MAD (mean absolute distance) of triangular shaped coordinates that could be obtained from 3 times repeated shooting by changing knock degree 120. The input-output data is collected for learning the correlation model, and ANN (artificial neural network) is used for implementing the model.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.21 no.1
• /
• pp.80-85
• /
• 2011

This paper presents the design of the power-assisted controller for the in-wheel type smart wheelchair by using torque estimation that is predicted by relationship between input voltage and output wheel angular velocity. Nowadays, interest of the moving assistant aids is increased according to the increase in population of the elderly and the handicapped person. However some of the moving assistant aids have problems. For example, manual wheelchair has difficulty moving at the slope, because users lack the muscular strength of their arm. In electric wheelchair case, users should be weak by being decreased muscles of upper body. To overcome these problems, power-assisted electric wheelchair are proposed. Most of the power-assisted electric wheelchair have the special rims that can measure the user's power. In here, the rims have to be designed to install the sensors to measure user's power. In this paper, we don't design the rim to measure the man power. To predict the man power, we propose a control algorithm of the in-wheeled electric wheelchair by using torque estimation from the wheel. First, we measure the wheel velocity and voltage at the in-wheel electric wheelchair. And then we extract driving will forces by using proposed mathematical model. Also they are applied at the controller as the control input, we verify to be able to control in-wheel type smart wheelchair by using simulation.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.9 no.2
• /
• pp.58-67
• /
• 1995

The paper describes the variation of magnetic fields caused by the operation of induction motors. The measuring system consists of the self-integrating magnetic field sensor, amplifier, and active integrator. From the calibration experiments, the frequency bandwidth of the magnetic field measuring system ranges from 20[Hz] to 300[kHz] and sensitivity is 0.234(mV/$\mu\textrm{T}$]. The magnetic fields generated under steady state and starting operations of duction motor are recorded by the proposed measuring system, and the fast Fourier transformation(FFT) of the measured data is performed to analyze the harmonic components. A single pulsed magnetic field is strongly caused by direct starting the induction motor, and its peak value is greater than 5 times as compared with the steady state value. The long transient duration and high intensity originates from the large inductance and dynamic characteristic of the induction motor, During the steady state operation of induction motor, subharmonics of magnetic field components, which depend on the pole number of induction motor, are observed. The lower order power-line harmonics can be inferred from the voltage flicker and current ripple which are derived from the torque fluctuation of induction motor. In the case of the induction motor drived by inverter, the harmonics of magnetic field are much more than those caused by direct starting method and are found generally to increase with decreasing the driving frequency.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.19 no.6
• /
• pp.1029-1044
• /
• 2017

The Discrete Element Method (DEM) is one of the useful numerical methods to analyze the behavior of the ground formation by computing the motion and interaction using particles. The DEM has not been applied in civil engineering but also a wide range of industrial fields, such as chemical engineering, pharmacy, material science, food engineering, etc. In this study, to review a performance of the spoke-type earth pressure balance (EPB) shield TBM (Tunnel Boring Machine), the commercial software based on the DEM technology was used. An analysis of the TBM during excavation was conducted according to two pre-defined excavation conditions with the different rotation speed of a cutterhead. During the analysis, the resistant torque at the face of the cutterhead, the compressive force at the cutterhead and shield surface, the muck discharge at the screw auger were measured and compared. Upon the two kinds of excavation conditions, the applicability of the DEM analysis was reviewed as a modelling method for the TBM.

• The Journal of Korean Academy of Prosthodontics
• /
• v.59 no.4
• /
• pp.515-522
• /
• 2021

Successful cases of the implant-assisted removable partial denture and implant overdentures are reported in which a few implants are additionally placed to secure the maintenance, support, and stability of the denture when there are a few residual teeth. When the lateral force applied to the tooth abutment and implant surveyed crown is minimized, the horizontal and rotational movement of the denture is significantly reduced which is an effective method that can improve the address in patients who complain of reduced retention and stability of their dentures. In this case, a small number of implants were placed to fabricate an implant-assisted removable partial denture with implant surveyed crown in the maxilla and implant overdenture with Locator^® attachment in the mandible to improve the retention, stability, and support of the dentures. The patient was satisfied with both functional and aesthetic aspects after the final dentures were delivered.

• International Area Studies Review
• /
• v.17 no.4
• /
• pp.109-130
• /
• 2013

This study aims to identify the priority for the Gwangyang and Qingdao hinterlands which are in the same category of benchmarking crowed paths. This study has been mainly done with comparison. There is certain limitation to use competitive factors of existing research so, this study has had proper competitive factors deriving from factors analysis and studied hinterland priority of competing factors by AHP. Major results are as follows. First, the factor analysis resulted in 20 factor that were 0.6 or higher loading level of commonality and then these 20 factors were divided into groups: operating factors, service factors, cost factors, port infrastructure factors, and hinterland conditions factors with the rotated component matrix analysis. Second, according to the result of top competitive factors, the best factor was the hinterland condition(0.256). The other factors such as infrastructure, economy, accessibility, incentive, and port traffic in hinterland were highly ranked in terms of general importance using multiple weights. Third, the result of detailed properties importance about the final alternative, Gwangyang hinterland was considered more highly than Qingdao hinterland in the port information system, the support a variety of administrative services, the efficiency of the customs, and the tax benefits.

• Industry Promotion Research
• /
• v.4 no.1
• /
• pp.11-20
• /
• 2019

This study relates to a fixing device for gas piping installed in a building such as an apartment or a building. The gas piping is fixed to the inside of the housing so as to buffer the gas piping in all directions, thereby relieving vibration caused by an earthquake or an impact, Disclosed is an earthquake-proof fixing device for a gas pipeline that can minimize damages caused by damage to an earthquake and a gas pipeline by preventing damage and breakage. An apparatus for fixing a gas pipe to a bracket provided on a wall or a wall of a building, the apparatus comprising: a housing coupled to a wall or a bracket and coupled to the inside of the housing; a gas pipe penetrating through the housing to fix the gas pipe; The first plate spring includes a first plate spring formed with a plurality of concave-convex portions that are elastically supported in four directions. The first plate spring is screwed to the front surface or the rear surface of the housing. The lower plate is coupled to one end and the other end, And a pair of first adjusting screws for adjusting the elastic force of the spring. Through this study, damage and damage of gas piping due to earthquake or impact can be minimized.