• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.1
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• pp.54-61
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• 2014

This paper proposes a driver supportive device with haptic cue function which can transmit optimal gear shifting timing to a driver without requiring the driver's visual attention. Its performance is evaluated under vehicle model considering automotive engine, transmission and vehicle body. In order to achieve this goal, a torque feedback device is devised and manufactured by adopting the MR (magnetorheological) fluid and clutch mechanism. The manufactured MR clutch is then integrated with the accelerator pedal to construct the proposed haptic cue device. A virtual vehicle emulating a four-cylinder four-stroke engine, manual transmission system of a passenger vehicle and vehicle body is constructed and communicated with the manufactured haptic cue device. Control performances including torque tracking and fuel efficiency are experimentally evaluated via a simple feed-forward control algorithm.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.60
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• pp.37-46
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• 2000

A biomechanical model of lower extremity in seated postures was developed to assess muscular activities of lower extremity involved in a variety of foot pedal operations. The model incorporated four rigid body segments with the twenty-four muscles to represent lower extremity This study deals with quasi-static movement to investigate dynamic movement effect in seated foot operation. It is found that optimization method which has been used for modeling the articulated body segments does not predict the forces generated from biarticular muscles and antagonistic muscles reasonably. So, the revised nonlinear optimization scheme was employed to consider the synergistic effects of biarticular muscles and the antagonistic muscle effects from the stabilization of the joint. For the model validation, three male subjects performed the experiments in which EMG activities of the nine lower extremity muscles were measured. Predicted muscle forces were compared with the corresponding EMG amplitudes and it showed no statistical difference. For the selection of optimal seated posture, a physiological meaningful criterion was developed for muscular load sharing developed. For exertion levels, the transition point of type F motor unit of each muscle is inferred by analyzing the electromyogram at the seated postures. Also, for predetermined seated foot operations exertion levels, the recruitment pattern is identified in the continuous exertion, by analyzing the electromyogram changes due to the accumulated muscle fatigue.

• Journal of KSNVE
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• v.9 no.3
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• pp.613-620
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• 1999

Brake judder{or cold judder) caused by the disc thickness variation(DTV) is investigated experimentally, This cold judder is often perceived by steering wheel vibration, brake pedal pulsation, and vehicle body vibration. In this paper, how the DTV profile affects the vibration characteristics of vehicle body is shown by order tracking analysis(OTA) and operational vibration analysis(OVA) The tri-axial vibrations are measured at the knuckle, lower rm, and the body side of the lower arm. Also, measured are the wheel speed and the detail DTV profile. The interpretations of OTA results in three directions of tested vehicle indicate the relative importance in the contribution of the run-out and the DTV to the judder vibration. Also, the OVA results show the prominent vibration amplitude of the lower arm in the direction of the vehicle movement. in which the second order of wheel speed is dominant. These results could be used to diagnose the judder problem and to establish the correction methods.

• Journal of Veterinary Clinics
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• v.9 no.1
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• pp.301-309
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• 1992

The present study was carried out to compare xylazine(2.2mg/kg, IV), xylazine/acepromazine(1.1mg/kg. IV : 0.2mg/kg, IV) and xylazine/diazepam(1.1mg/kg, IV :1.0mg/kg, IV) anesthesia, to determine useful method out of three kinds of anesthesia and tr evaluate this selected method at hypovolemic state. In xylazine, kylazine/acepromazine and kylazine/diazepam anesthesia, the heart rate was increases after administration of atropine until 10minutes after administration of anesthetics and then decreased gradually in all types of anesthesia. The respiratory rate was decreased after administration of anesthetics in all types of anesthesia. The body temperature was rarely changed in xyiazine/acepromazine and xylazine/diazepam anesthesia, but decreased continuously in xylazine anesthesia. In xylazine and kylazine/acepromazine anesthesia the pedal and corneal reflex were not disappeared completely, but reactions to pin pricking were disappeared. In xylazine/diazepam anesthesia their reflex and reactions were disappeared together. The time from head-up to standing was shortest(32.00min) in kylazine/diazepam anesthesia in comparision with xylazine and kylazine/acepromazine anesthesia. In xylazine/diazepam anesthesia, the heart rates in hypovolemic dogs were decreased soon after administration of anesthetics but recovered immediately. The changes in systolic and diastolic blood pressure in hypovolemic dogs revealed similar trends to their changes in normal dogs after administration of anesthetics. It is considered that rylazine/diazepam anesthesia is one of the useful anesthetic methods in healthy dogs and also in hypovolemic dogs.

• Journal of Korean society of Dental Hygiene
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• v.12 no.4
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• pp.685-693
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• 2012

Objectives : This research was conducted to find the subjective symptoms of musculoskeletal system for main jobs and job posture. Methods : A survey was conducted from September 15, 2011 to October 7, 2011 and 357 dental hygienists were responded. The survey was consisted of the working environment and medical equipments, psycho-social characteristics, health habits and education, job posture, subjective symptoms of musculoskeletal system pain, and so on. Results : In the survey on the frequency of job posture of dental hygienists by jobs, said they cast down or tilt their head by 15 degrees or more or twist or bend their back. The result of the analysis on the subjective symptoms of musculoskeletal system by main job showed that they experienced a pain in neck, shoulder, and back, although the order differed. The order of subjective symptoms of musculoskeletal system for casting down or turning head by 15 degrees or more, twisting or bending back, having shoulders not parallel to the ground, sitting at the end of a chair, and supporting the whole body with one leg or pressing on a pedal for treatment was from the shoulders to the neck to the back. The order of subjective symptoms of musculoskeletal system for having arms too far from the body or hunching for treatment and bending wrists inward or outward for treatment was from the shoulders to the back to the neck. Conclusions : Due to the characteristics of the job which requires one to have a proper view of a patient's oral cavity, most of the postures included casting down of head or bending of back. Therefore a development of new postures is needed to replace the existing job postures which pressure the musculoskeletal system. And shift rotation can be used as a preventive measure.

• Journal of Biosystems Engineering
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• v.35 no.5
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• pp.294-301
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• 2010

This study was performed to improve the utilization of the ROPS and seatbelt of tractors in Korea. We surveyed the ROPS and seatbelt use and the tractor related accidents through the personal interviews for 141 farmers. And comfort test for tractor seatbelts is done for 4 different subjects by measuring the body pressure distribution. The survey showed that 79.3% of the tractor accidents was overturning accidents. And, in case the tractor has ROPS and seatbelt, there was no serious injuries. With this results, we could confirm that ROPS and seatbelt is very effective devices for protecting drivers in overturning accidents. But, in case farmers didn't wear seatbelt, there was some fatal injuries. This shows the importance of the seatbelt use in working and driving tractors. Therefore, we tested the comfort of the tractor seatbelt for 4 different subjects operating the pedal in tractor seat simulator and in the tractor running on various roads. From the results of the static test in the Lab, it was shown that more the seatbelt anchorage point is far form SIP point, more the body pressure of the belly became higher, and more the subjects feel uncomfortable. Not only in the static test in the simulator, but also in the dynamic test in riding tractors, it was shown that non retractable seatbelt was more uncomfortable than retractable seatbelt. According to this study, we concluded that we need to promote the utilization of the ROPS and seatbelt use. And, the non retractable seatbelt need to be replaced by retractable seatbelt. Also, we recommend that the seatbelt anchorage position should to be in the seatbelt anchorage area of the ISO 3776 standard.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.33-41
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• 2003

The cardiopulmonary and anesthetic effects of tiletamine/zolazepam(TZ, 10 mg/kg IV), xylazine-tiletamine /zolazepam(XTZ, X: 1.1 mg/kg IM, TZ: 10 mg/kg IV) and medetomid-ine-tiletamine/zolazepam(MTZ, M: 30$\mu\textrm{g}$/kg IM, TZ: 10 mg/kg IV) were evaluated to 15 healthy mongrel dogs (4.16$\pm$0.65 kg). These dogs were randomly assigned to the three treatment groups(Control, XTZ, MTZ) with 5 dogs in each group. All experimental animals were premedicated with atropine(0.03 mg/kg, IM). Xylazine or medetomidine were administered to dogs in XTZ group and MTZ group 10 minutes after atropine injection. TZ was administered 20 minutes after atropine injection in all groups. The loss of pain response at pedal reflex and ear pinching tests in XTZ and MTZ groups were much longer compared with those of Control group(P < 0.01). All dogs in this study showed head rocking and hypersalivation during recovery time. Body temperature decreased progressively during experimental period in all groups, but it was not significant. After TZ injection, heart beat rate significantly increased 10 and 20 minutes in Control group, and 20 and 40 minutes in XTZ group(P < 0.05). Respiratory rate significantly decreased 0,10,20 and 40 minutes after 72 injection in XTZ and MTZ groups. In Control group, systolic arterial pressure (SAP) 20 minutes. diastolic arterial pressure(DAP) 10 minutes and mean arterial pressures (MAP) 10 and 20 minutes after 72 injection significantly decreased(P < 0.05). In XTZ group, SAP, DAP and MAP significantly decreased 20 and 40 minutes after 72 injection(P < 0.05). Thus, it was considered that XTZ and MTZ were useful in a canine surgical treatment that requires long anesthetic duration and deep analgesia.

• Science of Emotion and Sensibility
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• v.8 no.4
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• pp.423-433
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• 2005

The computer hardware development has provided many chances of emergence between art and technology. In many cases today's interactive artworks cannot be completed without audience's participation. The interactive production process with technical supplementation can be celled feedback. Mr. Nam Jun Paik showed 'Participant TV' that interacts with audience's response in real time. It means artwork changes with the constantly changing value from the data set from human visual perception. Dan Graham showed another feedback related work, which delays 5second playback in mirror that implies consequence of time. Today's media art has to sublimate coincidence, time ant audience into philosophical artwork through consonance that comes with video and sound as we can see from Bill Viola. Stelarc produced artworks. That use input data that is weak signals from brain, muscles. Through a terminal display with player, body expanded meaning of media. Jeffrey Shaw's 'Legible City' provided a fabrication of the reality with the interaction of bicycle's pedal speed and steering direction that is controlled by 4river. RE:MARK used microphone as input device as Edmond Couchot's 'Je same a la vent' and Nam Jun Paik's 'Participant TV' did. There is no communication without feedback between human being. The reality makes audience involved into artworks. That is the reason why feedback has to be natural. Through the feedback process, the originality of the idea is altered by audience. The feedback is not just part of flesh of artwork rather skeleton of it. Technological showoff cannot be art itself The perfection of technological application plan helps feedback that interacts with audience naturally in order that audience hoes not feel the feedback as artificial plan. Interactive media art has to be evolved into new media form with new integration feedback technology.

• Korean Journal of Cognitive Science
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• v.23 no.1
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• pp.109-132
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• 2012

According to recent embodied cognition approach, understanding of actions is not based on abstract symbolic process but based on mental simulation of sensory-motor information related to those actions. As supporting evidence, motor resonance effect is a facilitation/interference effect of motor response in terms of similarity between observed action and concurrent own action. In the current research, we investigated this effect in the situation to perceive a complex social action perception and how it would be modulated by perspectives of construals of the social action scene. For this purpose, we created three kinds of fighting action scenes of two people in terms of body actions of the subject(ie., hitting, stepping, biting), and described them in two perspectives; active and passive. During the experiment, subjects had to verify the congruency of the picture and the description first, and if they are congruent, they had to do two different actions in terms of color of following cues. In the first experiment, subjects' response time for stepping on a pedal and pressing a button were analyzed for measuring motor resonance effect for the foot movement. In the second experiment, voice response time with a microphone and button pressing time were analyzed for the mouth movement motor resonance effect. Results showed the facilitation of the foot movement(in Exp1), and the mouth movement(in Exp2) only when the action scene was described in active perspective. Our results indicate that the motor resonance effect can be occurred during perception of social actions in the real life situation, but it can be also modulated by the perspective of the mental construal of the action event.

• Tuberculosis and Respiratory Diseases
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• v.56 no.1
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• pp.77-84
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• 2004

Background : We hypothesized that there was a relationship between body weight change and bronchodilator response (BDR) in patients with chronic renal failure (CRF) on hemodialysis (HD). Several mechanisms such as pulmonary edema due to water retention or increased permeability of alveolar capillary may play a important role in pulmonary function impairment and bronchial hyperresponsiveness in patients with CRF on HD. But, no studies have been published concerning BDR in patients with CRF on HD. This study was aimed to know the immediate effect of hemodialysis on pulmonary function and BDR in patients with CRF on HD. Methods : This study included 30 patients with CRF on HD. We collected data including age, sex, height, pretibial and pedal pitting edema, interdialysis weight gain, postdialysis weight loss, underlying diseases, duration of HD, $FEV_1$, FVC, $FEV_1/FVC$, and BDR before and after HD. Results : Interdialysis weight gain of the patients was $3.4{\pm}1.0kg$, and postdialysis weight loss was $3.2{\pm}0.7kg$. Before HD,$FEV_1$, FVC, and $FEV_1/FVC$ of the patients were $89{\pm}22%$, $86{\pm}19%$ of predicted, and $87{\pm}10%$. After bronchodilator inhalation, these parameters were changed to $95{\pm}22%$, $90{\pm}19%$ of predicted, and $88{\pm}9%$ respectively. BDR was positive in 15 patients. After HD, $FEV_1$, FVC, and $FEV_1/FVC$ of the patients were $100{\pm}23%$, $94{\pm}18%$ of predicted, and $88{\pm}11%$. After bronchodilator inhalation, these parameters were changed to $102{\pm}23%$, $96{\pm}18%$ of predicted, and $89{\pm}8%$ respectively. BDR was positive in 9 patients. Conclusion : First, HD increases $FEV_1$, FVC, and $FEV_1/FVC$ but little affects BDR. Second, there is no correlation between postdialysis weight loss and increases in $FEV_1$, FVC, and $FEV_1/FVC$ after HD. Third, there is also no correlation not only between interdialysis weight gain and BDR before HD but between postdialysis weight loss and BDR after HD.