• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.545-550
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• 2001

This paper studied on the lateral motion and yaw motion of the gantry crane that is used for the automated container terminal. Though several problems are occurred in driving of the gantry crane, they are solved by the motion by the operators. But, if the gantry crane is unmanned, it is automatically controlled without any operator. There are two types, cone and flat type in driving wheel shape. In cone type, the lateral vibration and yaw motion of crane are issued. In flat type, the collision between wheel-flange and rail or the fitting between wheel-flanges and rail is issued. Especially, the collision between wheel-flange and rail is a very critical problem in driving of unmanned gantry crane. To bring a solution to the problems, the lateral and yaw dynamic equations of the driving mechanism of two driving wheels are derived. Then, we investigate the driving characteristics of gantry crane. In this study, the proposed controller, based on Model Based Controller, is used to control the lateral displacement and yaw angle of the gantry crane. And the availability of the proposed controller is showed through the comparison with the result of the proposed controller and PD controller. The simulation results of the driving mechanism, using the Runge-Kutta Method that is one of the numerical analysis methods, are presented in this paper.

• 대한기계학회논문집A
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• 제38권5호
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• pp.551-557
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• 2014

본 논문은 작업 시 농업용 트랙터의 운전지원을 위한 강인한 횡방향 제어기를 제안하고자 한다. 자동차와 달리 트랙터의 조향 방식은 유압실린더를 이용함으로써 상대적으로 큰 시간지연을 가지고 있으며 작업 시 지면 환경도 일반 도로와는 다르다. 조향 액추에이터 모델을 포함하는 기구학적 트랙터 모델을 기반으로 동적 표면 제어라는 비선형 제어기법을 적용하여 조향 액추에이터의 시간지연 및 노면 경사의 변화에 강인한 횡방향 제어기를 설계한다. 마지막으로 상용 트랙터 시뮬레이터를 이용하여 마찰 계수가 일정한 주어진 노면 상태에서 조향 액추에이터의 시간 지연 변경이나 오르막 또는 내리막과 같은 지형 조건 변화에 대한 횡방향 제어기의 성능 및 강인성을 검증한다.

• 대한통합의학회지
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• 제11권2호
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• pp.101-108
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• 2023

Purpose : To investigate effects of transcranial directed current stimulus (tDCS) combined with abdominal draw-in maneuver (ADIM) on balance ability and trunk impairment scale of chronic stroke patients. Methods : Twenty-six chronic stroke patients were recruited and twenty-four participated after excluding two patients who met the exclusion criteria. After screening tests, they were randomized through excel program into an experimental group (n = 12) to apply a tDCS combined with ADIM and a control group (n = 12) to apply a sham tDCS with ADIM. The intervention lasted three times a week for six weeks. To compare tDCS intervention effects, trunk impairment scale and balance ability were measured. Comparisons between experimental and control groups were statistically processed using an independent t-test and comparisons within groups were statistically processed using a paired t-test. Results : The experimental group showed significant increases of pre- and post-intervention medial lateral velocity, anterior posterior velocity and area of balance ability, and trunk impairment scale (p<.05). The control group showed significant increases in pre- and post-intervention medial lateral velocity of balance ability and trunk impairment scale (p< .05). The experimental group showed significant increases of medial lateral velocity of balance ability and trunk impairment scale compared to the control group (p<.05). Conclusion : Results of this study suggest that tDCS combined with ADIM for chronic stroke patients can be effective in improving medial lateral velocity of balance ability and trunk impairment scale. Thus, tDCS can be used as an effective treatment protocol for trunk rehabilitation of chronic stroke patients.

• 생물환경조절학회지
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• 제16권1호
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• pp.47-53
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• 2007

본 실험은 고품질의 콩나물 생산을 위한 기초연구로서 식물생장조절제를 이용한 세근발생 억제 및 하배축비대촉진을 위한 처리 방법을 구명하고자 실험을 수행하여 다음과 같은 결과를 얻었다. 식물생장조절제 중 $GA_3$나 NAA 처리는 세근발생 억제효과가 미약하였다. 반면 BAP처이믐 세근발생이 전혀 일어나지 않았고 하배축의 비대를 촉진하였는데, 저농도인 $10mg{\cdot}L^{-1}$ 및 $15mg{\cdot}L^{-1}$ 처리에서도 그 효과가 인정되었다. BAP의 처리시간은 짧을수록 하배축 비대가 촉진되었고 하배축 비대를 촉진하는 처리시간은 6시간 처리였다. BAP 처리 후 24시간 간격으로 관수는 세근 발생율이 낮았고 하배축 비대는 촉진되었다. 인돌비는 적정농도로 알려져 있는 4.2%보다 낮은 농도인 1.1%용액을 처리하더라도 세근 발생이 크게 문제되지 않았다.

• Clinics in Shoulder and Elbow
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• 제26권1호
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• pp.49-54
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• 2023

Background: Lateral epicondylitis is an increasingly debilitating condition in working population. Evidence for conservative treatment modalities has been inconclusive. Percutaneous pie crusting of the common extensor origin at the lateral epicondyle at the time of local corticosteroid injection (CSI) has been proposed sparsely. The objective of this study was to analyze if concomitant CSI and pie-crusting of the common extensor origin provides better outcome than CSI alone in lateral epicondylitis. Methods: This case-control study on 236 patients was conducted at a single center between January 1, 2020, and May 31, 2022. Patients were divided into two groups (n=118 each) based on their preference. Group A underwent CSI alone and group B underwent pie crusting along with CSI. The clinical and functional outcomes of all patients were evaluated at 2, 4, 6, and 12-week post-procedure using the visual analog scale (VAS) and Nirschl score. The mean time for return to daily activities was also compared. Results: Both groups showed significant improvement in post-procedure outcome at successive follow-ups on intragroup longitudinal analysis (VAS: F=558.384 vs. F=1,529.618, Nirschl: F=791.468 vs. F=1,284.951). On intergroup analysis, VAS of group B was superior to that of group A; however, it was statistically significant (P<0.05) only from the 6-week follow-up onwards. Nirschl score of group B was significantly better throughout the period of follow-up (P<0.05). Group B returned to daily activities faster than Group A (6.2±0.44 weeks vs. 7.18±0.76 weeks). Conclusions: Concomitant pie crusting with CSI is recommended for lateral epicondylitis as it provides significantly better results than CSI alone.

• 대한치과보철학회지
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• 제31권2호
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• pp.237-248
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• 1993

Although pantograph has been used to investigate whether the determinents of the mandibular movement were possible contributing factors of TMJ click, there was the problems to understand the role of tooth morphology upon the occurrence of click because of using appliance without tooth contacts. There Were advantages to evaluate the effects of tooth morphology upon the mandibular movements, because intraoral tracing device(Functiograph$^{(R)}$) had been obtained maintaining occlusal contact between the upper and lower natural teeth during mandibular movement. The purpose of this study was to record the mandibular eccentric movement quantitatively performed in 20 adult control subjects and 20 adult subjects with TMJ click and to investigate the effects of occlusion upon the occurrence of TMJ click. The obtained results were as follows : 1. The average ICP-P distance was $3.07{\pm}0.73mm$ in subjects with TMJ click, $2.14{\pm}0.85mm$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.001). 2. The average ICP-P distance was $3.07{\pm}1.14mm$ in subjects with TMJ click, $2.61{\pm}0.96mm$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.05). 3. The average distance of right and left lateral movement was not statistically significant between subjects with TMJ click and control subjects. 4. The average lateral displacement from midline during RCP was $0.75{\pm}0.54mm$ subjects with TMJ click, $0.16{\pm}0.17mm$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.001). 5. The average lateral displacement from midline during protrusive movement was $0.88{\pm}0.54mm$ in subjects with TMJ click, $0.20{\pm}0.23mm$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.001). 6. The average angle of right and left lateral movement was $144.2{\pm}20.20^{\circ}$ in subjects with TMJ click, $138.15{\pm}20.09^{\circ}$ in control subjects. There was a statistical significance between subjects with TMJ click and control subjects(P<0.05).

• 음성과학
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• 제8권4호
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• pp.139-156
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• 2001

Speech intelligibility in patients with complete dentures is an important clinical problem depending on the material used. The objective of this study was to investigate the speech of two edentulous subjects fitted with a complete maxillary prosthesis made of two different palatal materials: chrome-cobalt alloy and acrylic resin. Three patients with complete dentures in the experiment group and ten people in the controls groups participated in the experiment. CSL, Visi-Pitch were used to measure speech characteristics. The test words consisted of a simple vowel /e/, meaningless three syllabic words containing fricative, affricated and stops sounds, and sustained fricative sounds /s/ and /$\int$/. The analysis speech parameters were vowel and lateral formants, VOT, sound durations, sound pressure level and fricative frequency. Data analysis was conducted by a series of paired T-test. The findings like the following: (1) Vowel formant one of patients with complete denture is higher than that of the control group (p<0.05), while lateral formant three of patients with complete denture is lower than that of the control group (p<0.0l). (2) Patients with complete denture produced lower speech intelligibility with low fricative frequency (/$\int$/) than control group (p<0.0). The speech intelligibility of patients with metal prosthesis was higher than that of those with resin prosthesis (p<0.05). (3) Fricative, lateral and stop sound durations of patients with complete denture were longer than those of the control group (p<0.01 and p<0.05), respectively. Total sound durations of patients with metal prosthesis were similar to that of the control group (p<0.05), while those with resin prosthesis had a shorter duration (p<0.01). This implied that those with metal prosthesis had higher speech intelligibility than those with resin prosthesis. (4) Patients with complete denture had higher sound pressure levels /t/ and /c/ than the control group (p<0.01). However, sound pressure levels for /c/ of patients with metal prosthesis or resin prosthesis was similar to the control group (p<0.05). (5) Patients with complete denture had higher fundamental frequency than the control group (p<0.01).

• Wind and Structures
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• 제38권1호
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• pp.15-42
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• 2024

A flexible-base coupled-two-beam (CTB) discrete model with equivalent tuned mass dampers is used to assess the effect of soil-structure interaction (SSI) and different types of lateral resisting systems on the design of passive dynamic absorbers (PDAs) under the action of along-wind and across-wind loads due to vortex shedding. A total of five different PDAs are considered in this study: (1) tuned mass damper (TMD), (2) circular tuned sloshing damper (C-TSD), (3) rectangular tuned sloshing damper (R-TSD), (4) two-way liquid damper (TWLD) and (5) pendulum tuned mass damper (PTMD). By modifying the non-dimensional lateral stiffness ratio, the CTB model can consider lateral deformations varying from those of a flexural cantilever beam to those of a shear cantilever beam. The Monte Carlo simulation method was used to generate along-wind and across-wind loads correlated along the height of a real shear wall-frame building, which has similar fundamental periods of vibration and different modes of lateral deformation in the xz and yz planes, respectively. Ambient vibration tests were conducted on the building to identify its real lateral behavior and thus choose the most suitable parameters for the CTB model. Both alongwind and across-wind responses of the 144-meter-tall building were computed considering four soil types (hard rock, dense soil, stiff soil and soft soil) and a single PDA on its top, that is, 96 time-history analyses were carried out to assess the effect of SSI and lateral resisting system on the PDAs design. Based on the parametric analyses, the response significantly increases as the soil flexibility increases for both type of lateral wind loads, particularly for flexural-type deformations. The results show a great effectiveness of PDAs in controlling across-wind peak displacements and both along-wind and across-wind RMS accelerations, on the contrary, PDAs were ineffective in controlling along-wind peak displacements on all soil types and different kind of lateral deformation. Generally speaking, the maximum possible value of the PDA mass efficiency index increases as the soil flexibility increases, on the contrary, it decreases as the non-dimensional lateral stiffness ratio of the building increases; therefore, there is a significant increase of the vibration control effectiveness of PDAs for lateral flexural-type deformations on soft soils.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1651-1654
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• 1997

Restiction of vertical and lateral accelerations is one of the very important requierments which has to be satisfied on the practice of automatically controlled flights of the civil aviation passenger planes. This goal could be achived on the basis of the optimization procedure using specilly constructed quadratic performance index. In the report the application of this procedure to the parameteric optimization of the control laws with known structure for autopilot of midium-size aircraft in the level flight model is demonstrated. Performance index is calculted on the basis of the controllability grammian. Results of simulation of control processes in the lateral and longitudinal channels sre represented.

• 대한기계학회논문집A
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• 제27권5호
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• pp.666-672
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• 2003

This paper presents a design of the controller for vehicle lateral dynamics using active yaw moment. Vehicle lateral motion is incorporated with directional controllability and stability. These are conflicting each other from the view of vehicle handling performance. To compromise the trade-off between these two aspects, we suggest a new control algorithm based on the sliding mode with time-varying switching surface according to the body side slip angle. The controller can deal with the nonlinear region in vehicle driving condition and be robust to the parameter uncertainties in the plant model. Control performance is evaluated from the simulation for the vehicle of real parameters on the road with various tire-road frictions.