• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.48 no.7
• /
• pp.369-375
• /
• 1999

This paper presents the novel low-performance single-phase voltage regulator which has common arm between the AC/DC and DC/AC power converters and adopts appropriate switching strategy, resulting in the reduction of the number of switching devices. Moreover, by introducing the method to replace the method to replace the conventional AC condenser in filter circuit with the new low-cost type using two DC condenser, the whole voltage regulator system can be more compact, simpler and less expensive than conventional ones. The fully digital controller is designed using high speed DSP, and the proposed system is validated through the experimental results.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.5C
• /
• pp.371-377
• /
• 2008

In this paper, we present a framework for vision-based two-arm gesture recognition. To capture the motion information of the hands, we perform color-based tracking algorithm using adaptive kernel for each frame. And a feature selection algorithm is performed to classify the motion information into four different phrases. By using gesture phrase information, we build a gesture model which consists of a probability of the symbols and a symbol sequence which is learned from the longest common subsequence. Finally, we present a similarity measurement for two-arm gesture recognition by using the proposed gesture models. In the experimental results, we show the efficiency of the proposed feature selection method, and the simplicity and the robustness of the recognition algorithm.

• Journal of the Korean Society of Radiology
• /
• v.8 no.7
• /
• pp.461-466
• /
• 2014

The advantages and disadvantages of the various models of crushed ESWL (Extracorporeal Shock Wave Lithotripsy) and their various side effects due to pre-treatment have been reported. We look for the appropriate intensity of the shock wave in the electromagnetic ESWL treatment of patients with lower Inferior Ureter Stones and measure the total running time of C-arm saw. This study is based on the January-June 2014 launch of 65 patients of C university hospital located in Gyeongbuk, who conducted ESWL without pre-treatment. Patients are composed of 48 male and 17 female which were more common in men, while the most common age is 50s. The occurrence of lower urinary tract stones were left and they were more absent than 5mm in size in 39 of the most common. Optimal intensity is one of the suitable intensity of pain, and it is possible to switch the strength of impact to C if one appeals pain. In addition, the C-arm of the total operating time showed $241.73{\pm}30.37$ seconds, which is the size of the lower urinary tract that showed a significant difference (p <0.05). Therefore, ESWL treatment without pre-enforce treatment, the standard for the impact frequency and impact strength depending on the site of ureteral stones is required. The standard for total operating time of C-arm generated for ureteral stones is needed in order to reduce radiation exposure, and the standard for the total operating time for the criteria is needed depending on the site in order to minimize the exposure.

• Journal of Chest Surgery
• /
• v.22 no.2
• /
• pp.330-336
• /
• 1989

The patient was 47-year-old male who had suffered from aphasia and hemiplegia of the right side, but mental state was alert. On physical examination, BP was 130/80 mmHg in the right arm, but not checked in the left arm. The pulses of the left common carotid, brachial, and radial arteries were not palpable. The pulses of the right femoral, popliteal, and dorsalis pedis arteries were weakly palpable. Brain CT Scan revealed cerebral infarction of the left hemisphere. Aortogram showed occlusion of the left common carotid, and the right internal carotid and common iliac arteries. Subclavian steal phenomena were observed in the delayed aortogram. Double extra-anatomic bypasses; Axillo-Axillar bypass and Femora-Femoral bypass, were performed in the local anesthesia at two stages, because of risk of major operation under general anesthesia. Postoperatively, all pulses except for pulse of the left common carotid artery were equally palpable. On discharge, the hemiplegia of the right side was improved and able to walk with assistance.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.12 no.2
• /
• pp.149-156
• /
• 2007

The number of transformer and the size of transformer in inverter using 3-phase transformer could be reduced compare with a multi-level inverter using single phase transformer. but still the 3-phase transformer inverter needs many switches. In this study, we proposed the isolated multi-level inverter using 3-phase transformers and common arm, in this paper. Also, using phase angle control method with switching frequency equal to output fundamental frequency, harmonics component of output voltage and switching loss can be reduced. Finally, We tested multi-level inverter to clarify electric circuit md reasonableness through Matlab simulation and experiment by using prototype inverter.

• Journal of Industrial Technology
• /
• v.28 no.A
• /
• pp.167-176
• /
• 2008

Recently, lots of studies are performed in developing of active orthosis. Exact and simple muscle force estimation is important in developing orthosis which assists muscle force for disabled people or physical laborers. Hill-type muscle model dynamics is common method for estimation of muscle forces. In Hill-type muscle model, we must know muscle length and moment arm which largely affect muscle force. And several methods are proposed to estimate muscle length and moment arm using joint angle. In this study, we compared estimation results of those method with data from body model of opensim to find which method is exact for estimation of muscle length and moment arm.

• Journal of Chest Surgery
• /
• v.16 no.2
• /
• pp.170-174
• /
• 1983

Aortic arch syndrome is an unusual disease entity characterized by the narrowing or obliteration of major branches of the arch of the aorta regardless of etiology. We have experienced 2 cases. One of them was 22 years old office girl with 3 months history of headache, intermittent syncope and weakness and claudication on left arm especially during her physical exercise. On physical examination, pulseless on left antecubital and radial artery and blood pressure on left arm was inable to check and coldness with weakness were noted on the same side. Aortic angiography reealed 34% narrowing of left subclavian artery as that of right. But both common carotid artery and both axillary arterial patency were relatively good. Through right supraclavicular and left axillary incision, bypass graft with Gore-tex prosthesis (I.D. 6mm, Length 25 cm) was implanted from right subclavian artery on 2cm distal to origin of right common carotid arery to left axillary artery distal to axillary fossa. End to side anastomosis with preservation of left subclavian artery was done. Postoperative state was stable with blood pressure of 110/70 mmHg on left arm and palpable antecubital and radial pulsation. Another one was 41 year old male patient with 8 months history of pain and numbness on right upper arm and shoulder. On admission, right arm blood pressure was 110/80 mmHg, left arm was 160/110 mmHg, but other physical findings had no abnormalities. Angiography revealed segmental narrowing of right axillary artery on the beginning with 2 cm in length. Operative treatment with right wupraclavicular and right axillary incision, bypass graft with great saphenous vein (Length; 15 cm) from right subclavian artery between scalenus anticus and medius to axillary artery at distal end of axillary fossa was done. The authors report two cases of Aortic arch syndrome treated with bypass graft using Autograft or Gore-tex with good result.

• Journal of the Korean Society of Industry Convergence
• /
• v.14 no.4
• /
• pp.167-172
• /
• 2011

This paper investigated optimal design for slim wall mount arm for flat TV. Recently the number of flat TV sets in use went on increasing in TV market. As the flat TV sets are getting common, consumers came to need another requirements like aesthetic factor besides display performances. As the new TV sets tend to be slimmer due to aesthetic design, Wall mount also requires to be slimmer for aesthetic balance. Slim structures, however, are vulnerable to structural rigidity. In this study, slim wall mount arm has been designed by 3D CAD and DOE (Design of Experiments) and finite element analysis for optimal structural design were carried out to determine the design variables for minimize working stress of wall mount arm. Finally two optimal design conditions were selected through DOE and FEM and one of those was chosen under constraint of minimizing blanking developed length.

• Korean Journal of Computational Design and Engineering
• /
• v.20 no.3
• /
• pp.263-268
• /
• 2015

Due to an increased sitting time in work, lumbar disc disease is one of the most frequent diseases in modern days, and this occasionally requires surgery for treatment. Endoscopic disc surgery, one of the common disc surgeries, requires a process of inserting a guide needle to the target disc for which the insertion path is manually planned by drawing lines on the patient's skin while monitoring the fluoroscopic view of the lumbar. Such procedure inevitably exposes both surgeon and patient to the fluoroscopy radiation emitted from the c-arm for a long time. To reduce the radiation exposure time, this study proposes a computer assisted method of calculating the 3D guide needle path by using 2D c-arm images of the disc in 3 different angles. Additionally, a method of the guide robot control based on the 3D needle path was developed by implementing the Hand-eye Calibration method to calculate the transformation matrix between the c-arm and robot base coordinate systems. The proposed system was then tested for its accuracy.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2000.04a
• /
• pp.176-181
• /
• 2000

Collision free task planning for dual-arm robot which perform many subtasks in a common work space can be achieved in two steps : path planning and trajectory planning. path planning finds the order of tasks for each robot to minimize path lengths as well as to avoid collision with static obstacles. A trajectory planning strategy is to let each robot move along its path as fast as possible and delay one robot at its initial position or reduce speed at the middle of its path to avoid collision with the other robot.