• Journal of Korean Physical Therapy Science
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• v.5 no.2
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• pp.595-602
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• 1998

The purpose of this study was to investigate the effect of sequential intermittent pneumatic compression in patients with lymphedema who were hospitalized for three days at Samsung Medical Center. Thirty-three subjects with lymphedema was selected by physician referral. A selection of the patients was made according to the following criteria : 1) no known metastases, 2) no infection after the a difference of at least 10% in the volumes of edematous limb. All patients were treated with the Lympha-Press(Model 103-A). Circumferential limb mesurements was done before and after a 3-day treatment period. As a result of sequential intermittent pneumatic compression therapy. All extremity showed a decrease in circumferential measurements with the maximal reduction occurring at the wrist(55.75 %) for the upper extremities and at the lower 1/3 of calf (40.61%) for the lower extremities. Upper extremity arm was reduced by 42.1% and lower extremity leg by 33.61%. In contrast with this, the proximal levels of arm patients and leg showed comparatively poor reduction than distal levels. Almost 44.44% of arm patients and 5.26% of leg patients experienced significant reduction(> 50%) after compression therapy. These data clearly indicates that Sequential Intermittent Pneumatic Compression Therapy was effective treatment for reducing of extremity volume in patients with lymphedema. but this was variable degree and dependent on the amount of pre-existing lymphedema. Other factors such as duration of edema, etiology, previous history of radiology, age did not appear to influence the extend of improvement. Further sutdies will be necessary to determine long term benefit of this therapy.

• Journal of Drive and Control
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• v.18 no.1
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• pp.31-38
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• 2021

This study presents a new principle for driving the robot aimed at reducing the position error for the boresonic examination of turbine rotor. The conventional method of inspection is performed by installing manipulator onto the flange of the turbine rotor and connecting a pipe, which is then being pushed into the bore. The longer the pipe gets, the greater sagging and distortion appear, making it difficult for the ultrasonic sensor to contact with the internal surface of the bore. A pneumatic pressure will ensure the front or rear feet of the robot in close contact with the inner wall to prevent slipping, while the ball screw on the body of the robot will rotate to drive it in the axial direction. The compression force required for tight contact was calculated in the form of a three-point support, and a static structural simulation analysis was performed by designing and modeling the robot mechanism. The driving performance and ultrasonic detection ability have been tested by fabricating the robot, the test piece for ultrasonic calibration and the transparent mock-up for robot demonstration. The tests have confirmed that no slipping occurs at a certain pneumatic pressure or over.

• Journal of Biomedical Engineering Research
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• v.37 no.1
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• pp.39-45
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• 2016

A pressure measurement system was developed to verify magnitude and position of transferred pressure on the body surface during the intermittent pneumatic compression (IPC) which is one of the most well-known methods for the prevention of deep vein thrombosis (DVT). Eighty force sensing resistors (FSR) were arranged on a mannequin leg and a hardware controller sensed, digitized, and transferred pressure data every second while IPC was being applied. Finally, sensed pressure data were color coded and visualized on the 3D model with lab-developed software. The pressure data were also saved to files for further analysis. Using this measurement system, the changing pattern of pressure was measured on the mannequin leg by changing both chamber pressure and cuff tightness. As a result, net pressure transferred onto the body surface is dependent on chamber pressure and cuff tightness. Under the same chamber pressure, the tighter a cuff was worn, the wider compressed area was and the shorter compression cycle was. Also transferred pressure was proportional to both chamber pressure and cuff tightness.

• Journal of Aerospace System Engineering
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• v.4 no.2
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• pp.1-9
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• 2010

An airless tire has advantages over the conventional pneumatic tire in terms of flat proof and maintenance free. According to the recently disclosed inventions on the airless tire, non-pneumatic tire (NPT) consists of the flexible polygon spokes. Considering the NPT structure, the spokes undergo the tension-compression cyclic loading while the tire rolls. Therefore the spokes of NPT are required to have both stiffness and resilience under the cyclic tensile-compressible loading. In general, if a material has a high stiffness, it shows a low elastic strain limit. In this paper, using the auxetic honeycomb structure with negative poissons's ratio, the spokes of NPT tire are designed to have both stiffness and resilience. Finite element based numerical simulation of the contact pressure of a NPT is carried out with ABAQUS.

• Journal of Energy Engineering
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• v.20 no.4
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• pp.286-291
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• 2011

The hybrid vehicle has a good fuel economy with a electric type braking energy regeneration system. This paper introduced a novel pneumatic type braking energy regeneration system. The novel system use a scroll mechanism which have both compression function and expansion function. While vehicle is decelerating, the scroll machinery, being operated as a scroll compressor, compress a atmospheric air to save the vehicle's kinetic energy and reuse a compressed air which is reserved in a air tank while vehicle is accelerating. In order to analyze fuel improvements by applying braking energy regeneration system to a vehicle, we simulated the rate of braking energy regeneration through CVS-75 mode driving patterns.

• Journal of Biomedical Engineering Research
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• v.28 no.4
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• pp.569-576
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• 2007

Ventricular Assist Device(VAD) has switched its goal from a short-tenn use for bridge-to-transplantation to a long-tenn use for destination therapy, With this goal, the importance of long-tenn reliability gets more interests and importances, H-VAD is an portable extracorporeal biventricular assist device, and adopts an electro-pneumatic driving mechanism. The pneumatic pressure to pump out blood is generated with compression of bellows, and is transmitted in a closed pneumatic circuit through a pneumatic line. The existing pneumatic VAD adopts a air compressor which can generate stable pressures but has defects such as a noise and a size problem. Thus, it is not suitable for being used as a portable device, These problems are covered with adopting a closed pneumatic circuit mechanism with a bellows which has a small size and small noise generation, but it has defects that improper pneumatic setting causes a failure of adequate flow generation. In this study, the pneumatic pressure regulation system is developed to cover these defects of a bellows-type pneumatic VAD. The optimal pneumatic pressure conditions according to various afterload conditions for an optimal flow rate were investigated and the afterload estimation algorithm was developed, The final pneumatic regulation system estimates a current afterload and regulate the pneumatic pressure to the optimal point at a given afterload condition. The afterload estimation algorithm showed a sufficient performance that the standard deviation of error is 8.8 mmHg, The pneumatic pressure regulation system showed a sufficient performance that the flow rate was stably governed to various afterload conditions. In a further study, if a additional sensor such as ultrasonic sensor is developed to monitor the direct movement of diaphragm in a blood pump part, the reliability would be greatly increased. Moreover, if the afterload estimation algorithm gets more accuracy, it would be also helpful to monitor the hemodynamic condition of patients.

• Journal of Korean Academy of Nursing Administration
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• v.23 no.1
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• pp.63-75
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• 2017

Purpose: This study was conducted to adapt the standardized evidence-based nursing protocol using the IPC (intermittent pneumatic compression) intervention to prevent venous thromboembolism in surgical patients. Further, an investigation was done to measure knowledge on prevention of venous thromboembolism, surrogate incidence of venous thromboembolism and to assess IPC compliance in the study patients compared with those in surgical patients who underwent IPC intervention due to previous clinical experience. Methods: An analysis was done of the nine modules suggested by National Evidence-based Healthcare Collaborating Agency (NECA) in the adaptation manual of the clinical practice guideline for protocol adaptation. A nonequivalent control group post test design as a quasi-experiment was used to verify the effect of the IPC protocol. Results: There was a significant difference in knowledge of prevention of venous thromboembolism, IPC application time after intervention and the number of IPC applications between the experimental group (n=50) using the IPC nursing protocol and the control group (n=49). However, the symptoms of deep vein thrombosis and pulmonary thromboembolism were not observed in either the experimental group or the control group after the intervention. Conclusion: Results confirm that the standardized IPC nursing protocol provides effective intervention to prevent venous thromboembolism in surgical patients.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.193-196
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• 1996

A pneumatic cylinder has been used in the production facilities of various industries. However, it is difficult to achieve deciding the precise position of the piston rod, due to the nonlinear properties arising from the air compression and the friction. In recent years, the fuzzy control algorithm has been frequently applied to various kinds of systems on account of its simple algorithm, good adaptability to complex or nonlinear systems and so on. On the other hand, the PID or I-PD control has been used in many engineering fields because of the excellent performance. However, it is known that each one of them has disadvantages. In this paper, we propose a hybrid control which is strived to obtain the advantages of each other. It is shown that the proposed hybrid control performs better than the conventional I-PD control through the experimental results.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1994.04a
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• pp.57-64
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• 1994

The purpose of this paper is to find minimum surface shape of pneumatic structure using the finite element method. The pneumatic membrane structure is a kind of large deformation problem and very flexible composite material, which mean geomatric nonlinearity. It is not to resist for compression and resultant moment. As the displacement due to internal pressure is getting bigger, it should be considered the direction of forces. It becomes non-linear problem with the non-conservative force. The follower-force depends on the deformation and the direction of force is normal to each element. The solution process is obtained the new stiffness matrix (load correction matrix) depending on deformation through each iterated step. However, the stiffness matrix have not the symmetry and influence on the time of covergence. So in this paper Newton-Rhapson method for solving non-linear problem and for using symmetic matrix, the load direction is changed in each iterated step using the transformation matrix.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.22 no.3
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• pp.249-257
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• 2015

Purpose: The purpose of this pilot study was to investigate the effects of mechanical interventions for deep vein thrombosis (DVT) prophylaxis in surgical intensive care unit (SICU) patients. Methods: The participants were assigned to the intermittent pneumatic compression (IPC) and graduated compression stocking (GCS) intervention. Patients who met the criteria were selected for comparison from our previous study. Data for 140 patients were included in the final analysis. Results: The mean age was 57.5 (${\pm}15.7$) and 61.4 % were men. About forty-seven percent of the participants were 61 years or over. In the second duplex scan, 3, 2 and 1 critically ill patients developed deep vein thrombosis in the control, GCS, and IPC groups, respectively. Incidences of DVT were 6.0%, 5.0%, and 2.0% for the control, GCS, and IPC groups, respectively. This difference was not significant. Relative risks of no intervention were 3.0 and 1.2 compared with IPC and GCS application. There were no significantly different variables among the three groups before the intervention except for diagnosis on admission. Conclusion: Although it may difficult to conclude that mechanical prophylaxis effectively prevents DVT among SICU patients because there was no statistical significance in this study, but incidence rates among the three groups differed greatly. The findings reveal that further study should be conducted with larger samples and randomized controlled trial for SICU patients.