• Journal of the Korean Society for Aviation and Aeronautics
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• v.13 no.4
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• pp.1-10
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• 2005

According to the aviational definition, the fog is an obscuration phenomenon when prevailing visibility becomes less than 1,000m. Fog defined above causes so many aviation traffic problems like detour, flight delay and cancel. Therefore this study investigated quantitatively the fog effects on flight operation using flight delay and cancel statistic data during last four years from 1st Jul. 2001 to 30th Jun. 2005 at the Incheon Int'l Airport. The results of this study show that the hazardous meteorological condition is a important cause of flight delay and cancel, especially fog phenomenon. And it is expected that the results of this study give us the necessary and importance of fog prediction at the Incheon Int'l Airport.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.589-593
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• 2017

A single specimen of Kentrocapros flavofasciatus (measuring 145.9 mm in length) belonging to the family Aracanidae, order Tetraodontiformes, was collected for the first time in 2017 on Jeju Island, Korea. This specimen had isolated bony plates on a caudal peduncle, a carapace with six ridges, and a tail depth equal to its tail length. It is similar to K. aculeatus and K. rosapinto but differs from K. aculeatus in that its carapace is without spines; it differs from K. rosapinto in that the anterior end of its gill opening does not reach below the center of its eye. We propose new Korean names: Yug-gak-bok-gwa for the family Aracanidae, and Hwang-Jul-yug-gak-bok for the species K. flavofasciatus.

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.738-741
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• 2004

The overall performance of AC servo system is greatly affected by the uncertainties of unpredictable mechanical parameter variations and external load disturbances. Therefore, to compensate this problem, it is necessary to know different parameters and load disturbances subjected to position/speed control. This paper proposes an online identification method of mechanical parameters/load disturbances for AC servo system using Support Vector Regression (SVR). The proposed methodology advocates analytic parameter regression directly from the training data, rather than adaptive controller and observer approaches commonly used in motion control applications. The experimental results demonstrate that the proposed SVR algorithm is appropriate for control of unknown servo systems even with large measurement noise.

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.787-790
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• 2004

In this paper, a novel control scheme compensating for source voltage unbalance and current harmonics and power factor correction in unified active power filter systems combined with shunt passive filters is proposed, where no low/high-pass filter are used in deriving the reference voltage for compensation. Using digital all-pass filters, the phase angle and the reference voltages compensating for harmonic current and unbalanced voltage are derived from the positive sequence component of the unbalanced voltage. The amplitude of d-axis current in a series filter is controlled as zero for power factor correction. The validity of the proposed control scheme has been verified by experimental results.

• Proceedings of the KIPE Conference
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• 2004.07a
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• pp.312-315
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• 2004

This paper presents a tuning-free conditional integration anti-windup strategy for induction machine with Proportional-Integral (PI) type speed controller. The on/off condition of integral action is determined by the frequency domain analysis of machine torque command without a prior knowledge of set-point changes. There are no tuning parameters to be selected by users for anti-windup scheme. In addition, the dynamic performance of the proposed scheme assures a desired tracking response curve with minimal oscillation and settling time even in the change of operating conditions. This algorithm is useful in many high performance induction machine applications not to allow the oscillation and overshoot of speed/torque responses. The main idea can be extended to general applications such as chemical processes and industrial robots.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.5
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• pp.468-480
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• 2005

The overall performance of AC servo system is greatly affected the uncertainties of unpredictable mechanical parameter variations and external load disturbances. To overcome this problem, it is necessary to know different parameters and load disturbances subjected to position/speed control. This paper proposes an on-line identification method of mechanical parameters/load disturbances for AC servo system using support vector regression(SVR). The experimental results demonstrate that the proposed SVR algorithm is appropriate for control of unknown servo systems even with time-varying/nonlinear parameters.

• Journal of Chest Surgery
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• v.26 no.3
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• pp.204-208
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• 1993

The review of 68 patients, who were diagnosed as spontaneous pneumothorax during the period from Dec, 1991. to Jul, 1992. were performed thoracoscopy of 70 cases under local anesthesia with 1% lidocaine at the department of thoracic & cardiovascular surgery, HanYang University Hospital. Clinical data on distribution of Age & Sex, Location, Frequency of Reccurrence and other aspects of pneumothorax were summerized.37 cases were treated by thoracoscopic management and closed thoracostomy. As thoracoscopic management, Electrocauterization of bullae or blebs[37 cases], Endo-clip application [2 cases], Removal of foreign body[1 case] were performed. 31 cases were cured by open thoracotomy. The thoracotomy indications under thoracoscopic finding were followed as: 1. Severe pulmonary adhesion and destroyed lung parenchyme 2. multiple bullae or blebs on several areas 3. finding of pulmonary tuberculous caseous lesion 4. persistant air leakage after 7 days from thoracoscopic management Excision, wedge resection of bullae or blebs was performed in most cases [22 cases], 2 cases by median sternotomy and Segmentectomy of 7 cases were carried out depending on the pathologic change of lung.There was no operative mortality and Follow-up for all patients were showed good results.

• Journal of Chest Surgery
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• v.23 no.5
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• pp.899-904
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• 1990

One hundred and nine Patients with thoracic empyema were treated at the Chosun university hospital from Jul. 1983 to Sep. 1989. Seventy-nine[72.5%] of the empyemas were adults and 30[27.5%] patients were under fifteen-year children. 29 patients[26.6%] were associated with pulmonary tuberculosis, 23[21.1%] occurred as pneumonia, and 13[11.9%] were unknown. The cardinal symptoms were dyspnea, chest pain, fever, coughing. When used as the initial mode of drainage, repeat thoracentesis was successful in only 46 of 93 cases[49. 5%]. Rib resection, however, provided cure or controlled in 7 cases[100%]. And decortication showed high cure rate in 19 of 24 cases[79.2%] Eventual control or cure of empyema was achieved in 90 patients[89.6%], whereas 7 patients[6.4%] died [3 from their empyema and 4 with empyema as an active problem at the time of death]. of all empyema-caused deaths occurred in patients who underwent chest tube drainage as the most invasive treatment modality. Chest tube drainage was often inadequate and more aggressive management was likely to result in fewer treatment failure and fewer total procedure. Early rib resection was recommended.

• Animal Systematics, Evolution and Diversity
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• no.spc9
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• pp.30-36
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• 2016

As a part of the commemorative joint faunal survey for the 30th anniversary of the Korean Society of Systematic Zoology, the molluscan fauna of Jindo Island was investigated based on sample collection from 6 localities from the 6 to the 8 of Jul 2016. A total of 114 molluscan species from 47 families were collected and identified. Among these, 42 species from 11 families are newly reported from Jindo Island and combining the previous records with the present study totals 157 species from 57 families. Distribution of species records indicates that marine biogeography of Jindo Island represent an overlapping zone for marine organisms which dwell in the Yellow sea and the southern sea areas of Korean waters.

• Korean Journal of Construction Engineering and Management
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• v.11 no.2
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• pp.147-155
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• 2010

Traditional procurement methods have revealed many disadvantages especially the adversarial relationship between parties. After several decades of application, partnering has shown that it is an innovative arrangement that help to reduce many problems having existed in traditional arrangement. It can provide a win-win working attitude in a construction project. Partnering in construction has been applied in several ways in recent years in Vietnam. This mechanism can help both local and foreign construction participants to mutually offset their differences when implementing projects. This paper has investigated and introduced the incentives of partnering from Vietnam perspective in terms of foreign and local participants perceptions. It has been shown that 'to learn mutually among participants' and 'to increase bidding advantages' are the most important incentives according to foreign and local practitioners respectively.