• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.9
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• pp.777-784
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• 2007

With the development of micro electronic circuits and optical equipment, the demand for developing smart munitions with the ability to autonomously search for and attack targets has increased. Since the electronic components within smart munitions are affected by high temperatures, pressure, and impulsive forces upon the combustion of gunpowder, stability and reliability need to be secured for them. Securing those stability and reliability requires soft recovery system which can decelerate smart munitions. A theoretical analysis of flow is performed for the secure recovery of bullets on the basis of Euler equation for compressible fluids. The inner pressure on a pressure tube, the speeds of bullets, and the deceleration of munitions are calculated theoretically. Theoretical results are compared with the data from the experiment with soft recovery system set up at the laboratory.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.182-183
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• 2014

In case of large soft body impact test at the construction site, the test conditions are different from conditions at the laboratory, and the length of rope to hold the impact specimen must be changed. In a previous study, the fact that the size of impact load is varied by the length of rope on the large soft body impact specimen was confirmed. In this study, the length of rope and fall height were set as independent variables to conduct the load analysis test. It was determined that the load fluctuation was occurred depending on the length of rope under the fall height over 100 mm, and it is concluded that the additional setup of fall height to modify the actual impact load size is required when the length of rope is below 2.5 m. In this study, the modified formula to put equal size of impact load regardless of the length of rope was extracted through the experiment.

• Archives of Plastic Surgery
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• v.50 no.5
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• pp.523-528
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• 2023

The Gustilo IIIB tibiofibular fractures often result in long bone loss and extensive soft tissue defects. Reconstruction of these complex wounds is very challenging, especially when it includes long bone grafts, because the donor site is limited. We describe our experience using a set of chimeric ipsilateral vascularized fibula grafts with a thoracodorsal artery perforator free flap to reconstruct the traumatic tibia defects. A 66-year-old male suffered a severe comminuted tibia fracture and segmented fibula fracture with large soft tissue defects as a result of a traffic accident. He also had an open calcaneal fracture with soft tissue defects on the ipsilateral side. All the main vessels of the lower extremity were intact, and the cortical bone defect of the tibia was almost as large as the fractured fibula segment. We used an ipsilateral vascularized fibula graft to reconstruct the tibia and a thoracodorsal artery perforator flap to resurface the soft tissue, using the distal ends of peroneal vessels as named into sequential chimeric flaps. After 3 weeks, the calcaneal defect was reconstructed with second thoracodorsal artery perforator free flap. Reconstruction was successful and allowed rapid rehabilitation because of reduced donor site morbidity.

• The korean journal of orthodontics
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• v.35 no.3 s.110
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• pp.216-226
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• 2005

The purpose of this study was to test and compare the accuracy and reliability of soft tissue profile predictions generated from two computer software programs (Quick Ceph Image $Pro^{TM}$ (ver 3.0) and $V-Ceph^{TM}$(ver 3.5)) for mandibular set-back surgery. The presurgical and postsurgical lateral cephalograms of 40 patients (20 males and 20 females) were traced on the same acetate paper with the reference taken as the cranial base outline. The presurgical skeletal outlines were digitized onto each computer program and the mandible was moved to mimic the expected surgical procedure with reverence to the mandibular anterior border and lower incisor position of the actual postsurgical skeletal outline. The soft tissue profile was generated and the amount and direction of skeletal movement was calculated with each software. The predicted soft tissue profile was compared to the actual postsurgical soft tissue profile. There were differences between the actual and the predicted surgical soft tissue profile charges in the magnitude and direction, especially the upper lip. lower lip and the soft tissue chin (P<0.05). Quick Ceph had more horizontal measurement errors and thickness errors for the upper lip and lower lip, but V-Ceph had more vertical measurement errors of the lower lip (P<0.05). There was a positive correlation between the prediction errors and the amount of mandibular movements in the vertical position of Sn, the horizontal position of Ls and the upper lip thickness for V-Ceph, and there was a negative correlation in the horizontal position and the thickness of the lower lip for Quick Ceph (P<0.05). However all of the Prediction errors of both imaging softwares were ranged within 3mm, and this was considered to be allowable clinically.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.1
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• pp.87-108
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• 1996

This study was intended to perform cephalometric analysis of the facial soft tissue profile after surgical correction of skeletal Class III malocclusion after SSRO in 29 patients (Males 12, females 17). Lateral cephalograms were taken in centric occlusion before and immediate, long term after surgeries. 1. Counter-clockwise rotation of mandible was observed after the surgery, average relapses of mandibular set back were 1.23-1.28mm. The net effects of the mandibular set-back after surgeries were 81.7-82.2%. Because these relapse tendencies may reduce the effects of the surgical outcomes, surgeon must consider these net before the surgical treatment planning. 2. The ratio of horizontal changes of hard tissue to soft tissue at lower lip, mentolabial sulcus, pogonion were 72.7-93.7%, 100.3%, 99.1-102.1% respectively. There were little changes at upper lip position anteroposteriorly. 3. The relationship of upper and lower lips were improved after surgery. Lower lip was posteriorly repostioned and upper lip was flattend and elongated in conjunction with deepening of inferior lobial sulcus. But profile of chin was still prominent after surgery. 4. Hard tissue horizontal changes and tissue vertical changes were significantly correlated with each other and there were reverse correlations with hard tissue vertical changes and soft tissue horizontal changes.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.256-260
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• 2001

This paper presents boost and buck and buck-boost DC-DC converter circuit topologies of high-frequency soft switching transition PWM chopper type DC-DC high power converters with a single auxiliary passive resonant snubber. In the proposed boost power converter circuits operating under a principle of ZCS turn-on and ZVS turn-off commutation schemes, the capacitor and inductor in the auxiliary passive resonant circuit works as the loss less resonant snubber. In addition to this, the switching voltage and current peak stresses as well as EMI and RFI noises can be basically reduced by this single passive resonant snubber. Moreover, it is proved that converter circuit topologies with a passive resonant snubber are capable of solving some problems of the conventional hard switching PWM processing based on high-ferquency pulse modulation operation principle. The simulation results of this converter are discussed as compared with the experimental ones. The effectiveness of this power converter with a single passive resonant snubber is verified by the 5kW experimental breadboad set up.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.217-221
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• 2001

This paper presents a new prototype of soft-switching DC-DC power converter with a high frequency transformer link which has two active power controlled switches in full bridge rectifier with capacitor input type smoothing filter. In this DC-DC converter, ZVS of the inverter in transformer primary side and ZCS of active rectifier area in secondary side can be completely achieved by taking advantage of parasitic inductor component of high-frequency transformer and loss less snubbing capacitors. Its operation principle and salient features are described. The steady-state operating characteristics of the proposed DC-DC power converter are illustrated and discussed on the basis of the simulation results in addition to the experimental ones obtained by 2kw-40kHz power converter breadboard set up.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.26 no.1
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• pp.37-46
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• 2020

Background: The present study aimed to investigate the immediate effects of Soft Tissue Mobilization (STM) before Mobilization with Movement (MWM) on ankle ROM, pennation angle, balance in stroke patients. Methods: A total of 22 subjects were randomly assigned to one of two groups: the experimental group and the control group. The experimental group received intervention STM before MWM. STM was applied for one minute, MWM was applied one set of six times, in a total 3 sets. The passive ankle joint range of motion (ROM) was measured using a goniometer, the pennation angle was measured using RUSI, and the balance was measured using Timed Up & Go Test. Results: The ROM of the ankle dorsi-flexion, muscle tissue (pennation angle) and balance were significantly increased. Conclusion: In this study, it was confirmed that the ankle dorsi-flexion ROM, pennation angle of the medial gastrocnemius muscle, and balance were significantly improved in the group where STM was performed before the MWM intervention. Therefore, the physiotherapists should consider these results in their intervention. If MWM is applied to stroke patients, applying STM first is a better intervention.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1060-1067
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• 2005

This paper attempts to derive and analyze the dynamic system of pinching a rigid object by means of two multi-degrees-of-freedom robot fingers with soft and deformable tips. It is shown firstly that a set of differential equation describing dynamics system of the manipulators and object together with geometric constraint of tight area-contacts is formulated by Lagrange's equation. It is shown secondly that the problems of controlling both the forces of pressing object and the rotation angle of the object under the geometric constraints are discussed. In this paper, the control method for dynamic stable grasping and enhancing dexterity in manipulating things is proposed. It is illustrated by computer simulation that the control system gives the performance improvement in the dynamic stable grasping of the dual fingers robot with soft tips.

• Journal of Chest Surgery
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• v.35 no.8
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• pp.638-641
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• 2002

Low grade fibromyxoid sarcoma is a recently recognized, uncommon soft tissue neoplasm. It has a tendency to develop in deep soft tissue of young adults and a possibility of local recurrence or distant metastasis. Diagnostic criteria have not been well defined and this tumor has not been accepted as a distinct entity. Histologically, it is characterized by the presence of bland spindle cells with mainly whorled pattern of growth, set in alternating areas with a myxoid or fibrous stroma. Careful consideration of the morphological and immunohistochemical features of this tumor permit a positive diagnosis of low grade fibromyxoid sarcoma and allow its distinction from a number of other benign and malignant soft tissue neoplasms. We experienced a low grade fibromyxoid sarcoma in chest wall and report this case with a review of the literature.