• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.201-209
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• 2015

The deformed degree of car body varies largely with the collision part from side collision of car-to-car. In case of deformation of car body caused by collision, the movement is different as speed energy changes to strain energy. Generally, in the analysis of traffic accident, the movement of car after the collision is analyzed by law of conservation of motion and the error of energy absorption rate along the deformation of car body can be calibrated by inputting coefficient of restitution, but it is current situation that coefficient of restitution applied by referring to the research results of forward collision and backward collision because the research results of side collision is rare. Vehicle model of finite element method applied by structure of car body and materials of each component was analyzed by explicit finite element method, and coefficient of restitution and collision detection time along contact part of side collision was drawn by analyzing the results. Analysis result acquired through the law of conservation momentum by applying finally-computed coefficient of restitution and crash detection time compared to collision result of actual vehicle. As a result, the reliability of analysis was higher than the existing analysis method were acquired when applying the drawn initial input value that used finite element method analysis model.

• Journal of Acupuncture Research
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• v.31 no.1
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• pp.75-93
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• 2014

Objectives : This study was designed to establish medical trust realization system by finding factors influential to it using questionnaire. Methods : 277 subjects were participated in this study. After a treatment, we conducted a survey from April 1st to October 31th about medical service perception index, medical trust index, patient satisfaction index, patient reliability index, patient flow degree index, recall intension index, and hospital image index. To evaluate the influence of medical service perception with other 6 indexes, we statistically made regression analysis of the results through the survey. Results : By the results of the analysis, evaluation of hospital image influenced all 6 indexes. The systemicity of treatment process had an effect on 5 indexes except for the flow degree of patients. The humanity of medical team brought out the estimation of 4 indexes except for the patient flow degree and hospital image. The empathic ability of doctor and appropriacy of medical costs hold the next rank influencing 3 indexes. It reached the conclusion that the systemicity of medical team tend to determine the medical trust and patient reliability. The expertise, professional skill of doctor, the fault, commercial application, fame of medical team, the speed of treatment process, the newest and clean medical facility affected each one index. Conclusions : Korean medicine should find a way to consider the mind of patients for improving the medical quality through trust realization system, keeping up with times. As a result of this research, we can find out important causes which influence the trustful medical system. From now on, we should apply this result to actual treatment of psychology customized system. Also, more simple and clear questionnaire was organized through this research, it can be used to forward research to apprehend patient mentality more conveniently.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.12
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• pp.20-29
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• 2014

Recently, LTE is preparing to make a new leap forward LTE-A all over the world. As LTE privides high speed service, the role of mobile phones seems to change from voice to data service. According to Cisco, global mobile data traffic will increase nearly 11-fold between 2013 and 2018. Mobile video traffic will reach 75% by 2018 from 66% in 2013 in Korea. However, voice service is still the most important role of mobile phones. Thus, controllability of throughput and low BLER is indispensable for high-quality VoIP service among various type of traffic. Although the maximum AMR-WB, 23.85 Kbps is sufficient to a VoIP call, it is difficult for the LTE which can provide tens to hundreds of MB/s may not keep the certain level VoIP QoS especially in the cell-edge area. This paper proposes a new scheduling algorithm in order to improve VoIP performance after analyzing various scheduling algorithms. The proposal is the technology which applies more priority processing for VoIP than other applications in cell-edge area based on two-tier scheduling algorithm. The simulation result shows the improvement of VoIP performance in the view point of throughput and BLER.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.159-164
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• 2016

This paper reports the load factor logic design for a fly-by-wire helicopter flight envelope protection. As a helicopter is very complex system with a rotor, fuselage, engine, etc., there are many constraints on the flight region. Because of these constraints, pilots should consider them carefully and have a heavy workload, which causes controllability degradation. In this respect, automatic logic is needed to free the pilot from these considerations. As one of these logics, the flight envelope protection logic for the load factor of a FBW helicopter was designed. The flight to exceed the load factor is caused by an abrupt pitch cyclic stick change. In this scheme, the load factor limit logic was added between the pilot stick command block and pitch attitude command block. From the current load value, the available attitude range was calculated dynamically and simulated on the helicopter simulator model to verify the performance. A comparison of the simulation results at the hovering and forward speed region with and without applying the load limiting logic showed that the load factor limit was exceeded more than 20% when the logic was not applied, whereas with the load factor limit logic the load factor was within the limit. In conclusion, a dynamically allocated limitation logic to helicopter FBW controller was verified by simulation.

• Journal of Sensor Science and Technology
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• v.5 no.3
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• pp.101-108
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• 1996

The silicon $p^{+}-n$ junction diodes were fabricated. The fabricated wafers were treated by single or double annealing steps. Single annealing process was performed by diffusion of either Au or Pt into the wafer under the oxygen or nitrogen ambient at $800{\sim}1010^{\circ}C$. Second annealing step involved additional annealing of the single annealed wafer under the oxygen ambient at $800{\sim}1010^{\circ}C$ for one hour. Electrical characteristics of the diodes were investigated to evaluate the effect of the annealing treatments. In the case of single annealing under nitrogen ambient at $1010^{\circ}C$ for one hour, the amount of leakage current of Pt diffused diode was 75 times larger than that of Au diffused one. The optimum processing condition to achieve high speed silicon $p^{+}-n$ junction diodes from this study was obtained when Pt diffused wafer(treated under the nitrogen ambient at $1010^{\circ}C$ for one hour) was secondly annealed in an oxygen ambient at $800^{\circ}C$ for one hour. The resulting leakage current of two step annealed diodes were remarkably reduced to 1/1100 of the single annealed one. The diode characteristics such as recovery time, breakdown voltage, leakage current, and forward voltage were 4ns, 138V, 1.72nA, and 1V, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.688-696
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• 2016

This paper evaluates the effect of hot weather conditions on the fresh concrete characteristics of 80-MPa high-strength concrete. The slump flow, packing ability, setting time, hydration heat, and compressive strength were evaluated under exterior temperatures of $20^{\circ}C$, $30^{\circ}C$, and $40^{\circ}C$. The slump flow, arrival speed of 500 mm, and their changes with the elapsed time were found to bring the occurrence of rapid slump loss forward by about 30 minutes when increasing the temperature by $10^{\circ}C$ from $20^{\circ}C$. The initial and final setting times of the concrete at $20^{\circ}C$ were 7 hours and 12 hours, which were reduced by 1 hour and 3 hours at $30^{\circ}C$ and by 2 hours and 5 hours at $40^{\circ}C$, respectively. The hydration heat characteristics at $20^{\circ}C$ and $30^{\circ}C$ were similar in terms of the highest temperature of the concrete casting depth and the time when the maximum temperature occurred. However, at $40^{\circ}C$, the maximum temperature occurred about 4 hours earlier, and the highest temperature per the concrete casting depth increased by about $12^{\circ}C$. Therefore, it is concluded that the characteristics can vary according to the exterior temperature. Thus, quality assurance should consider workability, temperature cracks due to hydration heat, the properties of strength development, and other characteristics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1824-1832
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• 2011

In this paper, a smart home service robot McBot II is newly developed in much more practical and intelligent system than McBot I which we had developed a few years ago. Thus far, vacuum-cleaners have lightened the burden of household chores but the operational labor that vacuum-cleaners entail has been very severe. Recently, a cleaning robot was commercialized to solve but it also was not successful because it still had the problem of mess-cleanup, which pertained to the clean-up of large trash and the arrangement of newspapers, clothes, etc. Hence, we develop a new home mess-cleanup robot McBot II to completely overcome this problem on real environments. The mechanical design and the basic control of McBot II, which performs mess-cleanup function etc. in house, is actually focused in this paper. McBot II is mechanically modeled in the same method that the human works in door by using the waist and the hands. The big-ranged vertical lift and the shoulder joints to be able to forward move are mechanically designed for the operating function as the human's waist when the robot works. The mobility of McBot II is designed in the holonomic mobile robot for the collision avoidance of obstacle and the high speed navigation on the small area in door. Finally, good performance of McBot II, which has been optimally desinged, is confirmed through the experimental results for the control of the robotic body, mobility, arms and hands in this paper.

• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.95-104
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• 2005

To know the proper setup posture for the various clubs, changes of setup variables according to the change of golf club length was investigated. Swing motions of three male low handicappers including a professional were taken using two high-speed videocameras. Four clubs iron 7, iron 5, iron 3 and driver (wood 1) were selected for this experiment. Three dimensional motion analysis techniques were used to get the kinematical variables. Mathcad and Kwon3D motion analysis program were used to analyze the position, distance and angle data in three dimensions. The variables divided into three categories 1) position and width of anterior-posterior direction 2) position and width of lateral direction 3) angles and evaluated based on the theories of many good golf teachers. Major findings of this study were as follows. 1.The stance (distance between ankle joints) was increased as the length of the club increased but the increasing width was not large. It ranges from 5cm to 10cm and professional player showed small changes. 2. Forward lean angle of trunk was decreased (more erected) as the length of the club increased. It ranges from 30 degrees for iron7 to 25 degrees for driver. 3. Angle between horizontal and right shoulder were increased as the length of the club increased. It ranges from 10 degrees to 20 degrees and professional player showed small changes. 4. Anterior-posterior position of the shoulders were located in front of the foot for all clubs and the difference between the shoulder and knee position was decreased as the length of the club increased. 5. Anterior-posterior position of grip (hand) was located almost beneath the shoulders (2.5cm front) for iron7, but it increased to 10cm for the driver. This grip adjustment makes the height of the posture increased only 5cm from iron7 to driver. 6. Lateral position of grip located at 5cm left for the face of iron7, but it located at the right side (behind) for the face of driver. 7. Lateral position of the ball located at the 40%(15cm) of stance from left ankle for iron7 and located at the 10% (5cm) of stance for driver. 8. Head always located at the right side of the stance and the midpoint of the eyes located at the 37% of stance from the right ankle for all clubs. This means that the axis of swing always maintained consistently for all clubs. 9. Left foot opened to the target for all subject and clubs. The maximum open angle was 25 degrees. Overall result shows that the changes of the setup variables vary only small ranges from iron7 to driver. Paradoxically it could be concluded that the failure of swing result from the excessive changes of setup not from the incorrect changes. These findings will be useful for evaluating the setup motion of golf swing and helpful to most golfers.

• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.21-30
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• 2005

The purpose of this study is helps to make full use for perfect performance by grasping the defects of Tichonkich motion performed by athlete CSM For this, the study analyzed kinematical variables through Tichonkich motions performed at the first selection competition(1st trial) and final selection competition(2nd trial) for the dispatch to the 28th Athens Olympic Games using the three-dimensional cinematographical method with a high-speed video camera, and obtained the following results. 1. During Tichonkich motion, the execution time of up swing and the right hand moving to the left bar was shorter in the 2nd trial than the 1st one, while the execution time of down swing, the support of the left bar and the right hand moving to the right bar was longer in the 2nd trial than the 1st trial. 2. The horizontal position of COG in the 2nd trial was -35cm in the 1st stage, 42cm in the 3rd stage and 29cm in the 4th stage, that is, it showed a great swing focused on the circular movement compared to the 1st trial, while the vertical position of COG was -59cm in the 2nd stage, that is, it showed a small swing focused on a up and down movement. Also the 5th stage vertical position was 98cm, and the 6th stage vertical position was 95cm in the 2nd trial which were higher than those of the 1st trial, so it has provided magnificence required in the modern gymnastics. 3. And it was indicated that the horizontal velocity at the down swing phase proceeded forward more rapidly in the 2nd trial than that in the 1st trial, and the reverse ascent made a rapid vertical rise lessening left and right velocity change. And in the 5th stage, the 2nd trial was kept very slower in horizontal, vertical and left and right velocity that in the 1st trial, so it reached a handstand with leisurely movement. 4. In the 2nd trial, shoulder joint of the 1st, 2nd, 3rd stages kept a larger angle than that in the 1st trial, that is, it made a great swing while in the 1st trial, it showed a swing movement dependent on kick movement by the flexion and extension of hip joint. Also in the 2nd trial, the body formed a vertical posture with both hands supporting the left bar and hip joint was kept larger as $198^{\circ}$ and $190^{\circ}$ in the 5th and 6th stage than that in the 1st trial, so it made a handstand with the body uprightly stretched out, and magnificent and stable movement.

• Journal of Biosystems Engineering
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• v.43 no.4
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• pp.285-295
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• 2018

Purpose: The aim of this study is to develop a three-wheel riding cultivator for improving the performance of the current four-wheel riding cultivators in the market. Methods: A prototype three-wheel riding cultivator with the rated power of 15.5-kW, a primary hydrostatic and a two-speed selective gear transmission shifts, front/rear three-wheel drive, a hydraulic wheel tread adjustment, and the mid-section attachment of the major implements was designed and constructed. Its specifications and basic performance are investigated. Results: The maximum speeds of the prototype at the low and high stages were measured to be approximately 7.31, and 11.29 km/h in forward travel, respectively, and approximately 3.60, and 6.37 km/h in rearward travel, respectively. The minimum ground clearance is shown to be 670 mm. The rotating speeds of the power takeoff (PTO) shaft at the low and high stages are shown to be approximately 795 and 1,140 rpm, respectively. The tread of the rear wheels, the minimum radius of turning, and the maximum lifting height of the parallel link device are measured to be within 1,320-1,720 mm, 2.80 m, and 390 mm, respectively. Approximately 25.3% and 74.7% of the total weight of the prototype are distributed in the front and rear wheels on flat ground, respectively. When the tread of rear wheels increased from 1,320 to 1,720 mm, the left and right static lateral overturning angles increased from $33.4^{\circ}$ to $39.1^{\circ}$ and from $29.0^{\circ}$ to $36.1^{\circ}$, respectively. Conclusions: The prototype three-wheel riding cultivator showed a wide range of travel and PTO speeds, high minimum ground clearance, small minimum radius of turning, and easy control of the rear wheel tread. Further, the easy observation of cultivating operations by mid-mounting the implements can improve quality of work. Therefore, the prototype is expected to contribute to the riding mechanization of cultivating operations for various upland crops in Korea.