• Journal of the korean society of oceanography
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• v.38 no.3
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• pp.143-155
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• 2003

Current and sea level were observed in spring 1999 by a bottom mounted ADCP and tide gauge in the central part of the South Sea of Korea. With respect to the front, the distribution of isotherms is prograde in the offshore region whereas that of isohalines is retrograde, especially in the coastal area. The combined effect results in shoaling of isopycnals at the front. This distribution corresponds to a westward coastal flow on the northern side of the front and the eastward Tsushima Warm Current (TWC) to the south, determined by vessel-mounted ADCP observations. The low-frequency current shows either alternating clockwise-counterclockwise rotation or else persistent eastward motion depending on the frontal motion. Fluctuations of wind, sea level and current are coherent at period of 3-4 days and show some characteristics of Ekman-like dynamics.

• Journal of the Korean Mathematical Society
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• v.50 no.1
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• pp.61-80
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• 2013

In this paper, we study ${\alpha}$-completely positive maps between locally $C^*$-algebras. As a generalization of a completely positive map, an ${\alpha}$-completely positive map produces a Krein space with indefinite metric, which is useful for the study of massless or gauge fields. We construct a KSGNS type representation associated to an ${\alpha}$-completely positive map of a locally $C^*$-algebra on a Krein locally $C^*$-module. Using this construction, we establish the Radon-Nikod$\acute{y}$m type theorem for ${\alpha}$-completely positive maps on locally $C^*$-algebras. As an application, we study an extremal problem in the partially ordered cone of ${\alpha}$-completely positive maps on a locally $C^*$-algebra.

• Journal of Mechanical Science and Technology
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• v.15 no.7
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• pp.847-858
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• 2001

This paper considers the control model identification and H(sub)$\infty$ controller design for a tandem cold mill (TCM). In order to improve the performance of the existing automatic gauge control (AGC) system based on the Taylor linearized model of the TCM, a new mathematical model that can complement the Taylor linearized model is constructed by using the N4SID algorithm based on subspace method and the least squares algorithm based on ARX model. It is shown that the identified model had dynamic characteristics of the TCM than the existing Taylor linearized model. The H(sub)$\infty$ controller is designed to have robust stability to the system parameters variation, disturbance attenuation and robust tracking capability to the set-up value of strip thickness. The H(sub)$\infty$ servo problem is formulated and it is solved by using LMI (linear matrix inequality) techniques. Simulation results demonstrate the usefulness and applicability of the proposed H(sub)$\infty$ controller.

• Journal of Mechanical Science and Technology
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• v.17 no.2
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• pp.181-186
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• 2003

In order to assure the quality of the bent axis design axial piston pumps driven by tapered pistons, it is necessary to know the characteristics of force applied to tapered pistons and the mechanism for driving the tapered pistons. Since they are able to perform both reciprocating and spinning motions in cylinder block, it is difficult to understand the driving mechanismand-tomeasure the forces applied to tapered pistons experimentally In the present study, the theoretical mechanism for driving the tapered pistons is studied by use of the geometric method. The driving area of the tapered pistons is measured by measuring the strain of a cylinder forced against a tapered piston using an electric strain gauge and a slip ring. The forces applied to tapered pistons is also investigated with the change of discharge pressure and the rotational speed. As a results of this investigation, it is concluded that the cylinder block is driven by one tapered piston in a limited area and the driving area is changed due to space angle of the tapered pistons and the swivel angle of the cylinder block. It is also observed that the force applied to tapered pistons increases as the discharge pressure and the rotational speed increase.

• Journal of the Korean Society of Costume
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• v.47
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• pp.125-142
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• 1999

Dancing along with mankind has existed in various ways form old age to the present. This dancing combined with artistic meaning is called the art of dancing. This study is mainly about the functions decorations and expressions of dancing costume and the claracteristics of the costumes by the 20th century designers Leon bakst Oskar Schlemer Pablo Picasso. The dancing costume were not so much different from those of the public from old age to middle age. In 18th and 19th centuries the length of the cotstumes become short from the knee to the thigh. The functions have much to do with the development of dancing for example the appearance of toeshoes. The costumes are designed not to prevent the movements of dancers smooth line in old age and ladylike vend high-blown line in the 18th and 19th centuries. Cotton and hemp textiles are turning into the transparent forms such as lace and gauge. The personal ornaments earings and necklaces have change into the pattern with wings and tassels. The dancing costumes of Leon Bakst Oskar Schlemer and Pablo Picasso are designed after the due consideration of body shape. Bakst focused on the beauty of smooth lines with splendid colors and decorations. Schlemer analyzed the body abstractly and metaphysically and expressed it with detaile and simple lines. Picasso emphasized cubic forms with cubism and expressed the characteristics of costumes with clear colors and smooth curved line. Bakst Schlemer and Picasso made the early 20th century the age of functional dancing costumes putting a light on the concept of space and foundation for the modern dancing costumes.

• The Korean Journal of Pain
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• v.10 no.2
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• pp.254-257
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• 1997

Ganglion impar lies immediately anterior to the sacrococcygeal junction and blockade of the ganglion is used to treat anorectal and perineal pain. Although the technique introduced by Plancarte et at is widely practised, the bent needle is sometimes difficult to position precisely and patients find the procedure painful. We modified this approach of block of ganglion impar by positioning the needle into the sacrococcygeal junction and using the loss of resistance technique. With the patient in the lateral position, a skin wheal was raised at 1-1.5cm below the sacral hiatus. Twenty-three gauge short needle was directly placed into the sacrococcygeal junction with aid of fluoroscopic guidance. From 1 cm behind the anterior margin of the vertebral body in lateral view, we used the loss of resistance technique to confirm the retroperitoneal space. We found this modified approach easier to perform during six blocks for three patients with anorectal or perineal pain. Our modified approach through the sacrococcygeal junction may provide opportunity for wider administration of this procedure because of its simple technique, reduced pain during procedure and decreased risk of infection.

• The Korean Journal of Pain
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• v.1 no.1
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• pp.98-102
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• 1988

In order to control the pain after hemorrhoidectomy and anal fistulectomy, 6 mg of 0.5% hyperbaric tetracaine without(control, group I) or wilt 0.3 mg(group II) or 0.5 mg (group III) of 0.1% morphine was injected with a 22 gauge spinal needle into the subarachnoid space through L 3-4 interspace of patients in lateral position. About 30 minutes in Fowler' sposition after injection, operation was performed in lithotomy position. All the patients who ha4 morphine showed remarkable relief of postoperative pain for an average of 27 hours. However, the dosage(0.3 or 0.5 mg) of morphine administered did not affect the duration of pain relief. Blood pressure, pulse rate and pupil size were unchanged in all patients. Dysuria after block developed for on average of 5,6, 13.2 and 14.6 hours in group I, II and III respectively. Most of these cases required urethral catheterization. Minor complications such as nausea, vomiting, itching, fever, burning sensation and paresthesia were observed 16.7, 20 and 20% of cases in group I, II and III respectively; however, no treatment was required.

• Archives of Plastic Surgery
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• v.40 no.6
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• pp.761-765
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• 2013

Background Partially resecting ribs of the recipient site to facilitate easy anastomosis of the internal mammary vessels to free flaps during breast reconstruction can cause chest wall pain or deformities. To avoid this, the intercostal perforating branches of the internal mammary vessels can be used for anastomosis. The purpose of this study was to investigate the location and size of the internal mammary perforator vessels based on clinical intraoperative findings and to determine their reliability as recipient vessels for breast reconstruction with microsurgical free tissue transfer. Methods Twelve patients were preoperatively screened for the presence of internal mammary perforators using Doppler tracing. After modified radical mastectomy was performed by a general surgeon, the location and size of the internal mammary perforator vessels were microscopically investigated. The external diameter was examined using a vessel-measuring gauge from a mechanical coupling device, and the distance from the mid-sternal line to the perforator was also measured. Results The largest arterial perforator averaged 1.5 mm, and the largest venous perforator averaged 2.2 mm. Perforators emerging from the second intercostal space had the largest average external diameter; the second intercostal space also had the largest number of perforators arising from it. The average distance from the mid-sternal line to the perforator was 20.2 mm. Conclusions Internal mammary perforators presented consistent and reliable anatomy in this study. Based on these results, the internal mammary perforators appear to have a suitable diameter for microvascular anastomosis and should be considered as an alternative recipient vessel to the internal mammary vessel.

• The Korean Journal of Pain
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• v.12 no.1
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• pp.59-63
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• 1999

Background: Contraction of anal sphincter muscle produces severe pain in perianal surgery postoperatively. Recent reports have indicated that effective and prolonged pain relief can be obtained by the injection of small doses of morphine into the subarachnoid space. We attempted to use this technique for perianal surgery and investigated postoperative pain control and its side effects. Methods: Forty five patients scheduled for hemorrhoidectomy and anal fistulectomy were studied to determine the minimal effective dose of intrathecal morphine for postoperative analgesia. In order to control the pain, 7 mg of 0.5% hyperbaric bupivacaine with 0.05 mg (group I), 0.1 mg (group II) and 0.15 mg (group III) of morphine hydrochloride was injected with a 25 gauge spinal needle into the subarachnoid space. We estimated the duration of analgesia until the pain score attained to above 3 in 10 cm VAS (visual analogue scale) and incidence of itching, nausea and vomiting by percentage, headache, backpain and respiratory depression by positive and negative. We also checked the time of self-voiding. Results: The mean time of analgesia was $10.3{\pm}1.54$, $19.7{\pm}2.22$ and $20.3{\pm}2.29$ hours in group I, II and III respectively. Urinary retention of group I, II and III after block persisted for an average of $20.3{\pm}2.31$, $21.2{\pm}2.51$ and $23.3{\pm}3.74$ hours. Nausea and vomiting were observed 33%, 53%, 67% and itching was observed 53%, 67%, 80% in group I, II and III respectively and respiratory depression did not occur in all groups. Conclusions: It is not necessary to use more than 0.1mg of intrathecal morphine in perianal surgery because analgesia is not prolonged and side effects are increased.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.2
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• pp.81-89
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• 2019

In this study, wind tunnel test on Quad-Tilt Propeller which has tandem wings is carried out to analyze the aerodynamic interference effect of front wing and propeller on rear wing during forward flight. Using 6-axis balance system, forces and moments of whole aircraft were measured and using strain gauge at wing root, bending moments were measured to observe change of aerodynamic force of each wings. A 12-hole probe was used to measure the flow field in the wing and propeller wake. Flow characteristics were observed qualitatively through flow visualization experiment using tuft and smoke. To measure the aerodynamic interference by elements, the influence of front wing and propeller on rear wing was analyzed by changing the wings and propellers mount combination.