• Journal of Advanced Marine Engineering and Technology
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• v.38 no.6
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• pp.648-657
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• 2014

This paper is about the study on a newly developed small waterproofed 4-axis robot arm and the analysis of its kinematics and dynamics. The structure of robot arm is designed to have Pitch-Pitch-Pitch-Yaw joint motion for inspection using a camera on itself and the joint actuator driving capacity are selected and the joint actuators are designed and test for 10m waterproofness. The closed-form solution for the robot arm is derived through the forward and inverse kinematics analysis. Also, the dynamics model equation including the damping force due to the mechanical seal for waterproofness is derived using Newton-Euler method. Using derived dynamics equation, a sliding mode controller is designed to track the desired path of the developed robot arm, and its performance is verified through a simulation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37B no.10
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• pp.912-920
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• 2012

In this paper, we derived a closed-form equation of a Best Linear Unbiased Estimator (BLUE) estimator for the 3 dimensional estimation of the position of the emitter based on the Time Difference of Arrival (TDOA) technique. The BLUE derived for the case of estimating 3 dimensional position of the emitter with 4 base stations or sensors, and for this purpose, we used an approximated equation of the TDOA hyperbola equation obtained from the first order Taylor-series after setting the reference points of the position. The derived equation can be used for any kind of noises which are uncorrelated in each other in the TOA measurement noises and for a white Gaussian noise also.

• Journal of Communications and Networks
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• v.16 no.6
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• pp.627-638
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• 2014

In this paper, we study the joint price and power allocation in spectrum sharing macro-femtocell networks. The proposed game theoretic framework is based on bi-level Stackelberg game where macro base station (MBS) works as a leader and underlaid femto base stations (FBSs) work as followers. MBS has fixed data rate and imposes interference price on FBSs for maintaining its data rate and earns revenue while FBSs jointly adjust their power for maximizing their data rates and utility functions. Since the interference from FBSs to macro user equipment is kept under a given threshold and FBSs compete against each other for power allocation, there is a need to determine a power allocation strategy which converges to Stackelberg equilibrium. We consider two cases for MBS power allocation, i.e., fixed and dynamic power. MBS can adjust its power in case of dynamic power allocation according to its minimum data rate requirement and number of FBSs willing to share the spectrum. For both cases we consider uniform and non-uniform pricing where MBS charges same price to all FBSs for uniform pricing and different price to each FBS for non-uniform pricing according to its induced interference. We obtain unique closed form solution for each case if the co-interference at FBSs is assumed fixed. And an iterative algorithm which converges rapidly is also proposed to take into account the effect of co-tier interference on interference price and power allocation strategy. The results are explained with numerical simulation examples which validate the effectiveness of our proposed solutions.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.3
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• pp.323-328
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• 2009

In this paper, a decentralized fuzzy output feedback controller for the nonlinear networked control system is proposed for wireless sensor network. Especially, it is assumed that the networked control system has the output packet loss and the input transmission failure. For the fuzzy control of the nonlinear subsystem, it presents Takagi-Sugeno (T-S) fuzzy model of each subsystem and it designs the decentralized fuzzy output feedback controller. The stability condition of the closed-loop system with the proposed controller is obtained by Lyapunov functional. The obtained stability condition is represented to the linear matrix inequality (LMI) form, and the control gain is obtained by LMI. An example is given to show the verification discussed throughout the paper.

• The Journal of the Korea Contents Association
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• v.6 no.12
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• pp.147-154
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• 2006

The final purpose of this study is to explore morphological change of Shenyang in the period of the rising Chung Dynasty. For that purpose we have tried to build the historical GIS DB of site and analysis of the structure and shape pattern of the city by using the functions of GIS. From the view of spatial structure and cultural context, main characteristics, which is derived from the analysis of ancient map of Shenyang, can be summarized into five things as follows ; transformation of open spatial structure into closed structure, combination of horizontal spatial structure with vertical structure, transformation of practical spatial structure into symbolic structure, transformation of natural spatial structure into institutional form of ancient Chinese capital city, conservation of traditional Manchurian culture.

• Archives of Plastic Surgery
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• v.35 no.2
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• pp.197-200
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• 2008

Purpose: A congenital lacrimal sac fistula is unusual and consists of a dimple opening below the medial canthal tendon that leads to the lacrimal sac. This anlage ducts occur when the lacrimal anlage cells proliferate and canalize rather than involute. And, the anomaly is usually not associated with any systemic abnormalities. Also congenital cleft of the earlobes is rarely seen among congenital ear anomalies. Therefore, we report rare case with symptomatic bilateral lacrimal fistula with the ear cleft. Methods: A 4-year-old boy was admitted with aggravated chronic maxillary sinusitis, recurrent chronic dacryocystitis, and epiphora. He had two minor anomalies including bilateral lacrimal fistula originated in lacrimal tear sac and unilateral transverse ear cleft. The patient had been operated with fistulectomy and perioperative antibiotics. A small vertical ellipse is made around the opening with sharp dissection. The tract is excised using the probe as the guide. Another probe is placed through the lower canaliculus to prevent the damage. A suture ligature of 6-0 Maxon is placed around the deepest point of the tract, which is then excised. Additional sutures are placed in the tissues to form a tight closure to prevent reestablishment of the fistula. The skin is closed with 6-0 Black Silk. Results: The patient recovered well without any complications such as infection, epiphora, and obstruction of lacrimal sac. Conclusion: Our case illustrates bilateral lacrimal anlage ducts in a patient with unilateral congenital ear cleft. We recommend careful evaluation of lacrimal system in these patients, especially bilateral case and other congenital anomalies. Finally, we recommend excision of the ducts when epiphora, infection, or chronic skin irritation occur.

• The Korean Journal of Applied Statistics
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• v.26 no.1
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• pp.37-47
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• 2013

A Q-Q plot is an effective and convenient graphical method to assess a distributional assumption of data. The primary step in the construction of a Q-Q plot is to obtain a closed-form expression to represent the relation between observed quantiles and theoretical quantiles to be plotted in order that the points fall near the line y = a + bx. In this paper, we introduce a Q-Q plot to assess goodness-of-fit for inverse Gaussian distribution. The procedure is based on the distributional result that a transformed random variable $Y={\mid}\sqrt{\lambda}(X-{\mu})/{\mu}\sqrt{X}{\mid}$ follows a half-normal distribution with mean 0 and variance 1 when a random variable X has an inverse Gaussian distribution with location parameter ${\mu}$ and scale parameter ${\lambda}$. Simulations are performed to provide a guideline to interpret the pattern of points on the proposed inverse Gaussian Q-Q plot. An illustrative example is provided to show the usefulness of the inverse Gaussian Q-Q plot.

• Journal of Chest Surgery
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• v.22 no.2
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• pp.308-314
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• 1989

Pulmonary sequestration is a congenital malformation characterized by an area of embryonic lung tissue that derives its blood supply from an anomalous systemic artery. Two forms recognized: extralobar and intralobar. Extralobar form is a very rare congenital malformation, usually located in the lower chest, and may be found in newborn infants at the time a congenital diaphragmatic hernia is repaired. Large sequestrated segments may be cause acute respiratory distress in the neonate. The condition is asymptomatic in 15 per cent of patients. This report presents two cases of pulmonary sequestration which misdiagnosed a superior mediastinal tumor and a benign lung tumor. First case was 30-year-old male patient and chief complaints were dyspnea, dry cough and right chest pain. Chest X-ray showed a homogenous increased density of smooth margin at the right superior mediastinal area and suggested a benign mediastinal tumor. And so explothoracotomy was made without other special studies. Second case was 28-year-old male patient. One month ago, he had tracheostomy and right closed thoracostomy due to massive hemoptysis and spontaneous hemothorax. Chest X-ray showed a benign cystic lesion at RLL area. At the time of operation, in first case, a mass of adult fist size was placed medial to the right upper lobe and densely adhesive to trachea, SVC and esophagus. Blood supply of the mass was bronchial arteries of trachea and RUL bronchus and drained to SVC and azygos vein through anomalous systemic veins. There was no bronchial communication on Frozen biopsy. In 2nd case, large cystic lesion contained old blood hematoma was located in RLL and anomalous blood vessel from thoracic aorta was drained to posterior segment of RLL. In operation field, intralobar pulmonary sequestration was diagnosed, and RLL lobectomy was carried out.

• Journal of Korea Water Resources Association
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• v.49 no.7
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• pp.615-623
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• 2016

This Study calculated the Submerged Flow Characteristics and Discharge coefficient by the rising angular change of the Improved-Pneumatic-Movable. According to the result, the smaller the ratio of weir height and weir length (L/W) or the weir standing angle, the bigger of the downstream head ($H_2$). The change of discharge reduction factor ($Q_s/Q_1$), by the hight from weir crest to downstream surface and the ratio form weir crest to upstream water height ($h_t/H$), was decreased when the $h_t/H$ closed to number 1. Although the weir water depth of the down-stream was shallower level than the up-stream, the velocity was faster then before. And the more the flow, the less the gab between the upper and lower reaches level. And when the same flow condition, the downstream head ($H_2$) was increased when the L/W was bigger. The Submerged Flow Discharge coefficient of Improved-Pneumatic-Movable weir was made by the upstream approach flow head and the upper lower stream flow condition, not by the physical data of Movable weir.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.5 s.182
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• pp.37-43
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• 2006

Fitting process carried out in automobile transmission assembly line is classified into three classes; heat fitting, press fitting, and their combined fitting. Heat fitting is a method that heats gear to a suitable range under the tempering temperature and squeezes it toward the outer diameter of shaft. Its stress depends on the yield strength of gear. Press fitting is a method that generally squeezes gear toward that of shaft at room temperature by press. Another method heats warmly gear and safely squeezes it toward that of shaft. Warm shrink fitting process for automobile transmission part is now gradually increased, but the parts (shaft/gear) assembled by this process produced dimensional change in both outer diameter and profile of the gear. So that it may cause noise and vibration between gears. In order to solve these problems, we need an analysis of warm shrink fitting process, in which design parameters are involved; contact pressure according to fitting interference between outer diameter of shaft and inner diameter of gear, fitting temperature, and profile tolerance of gear. In this study, an closed form equation to predict contact pressure and fitting load was proposed in order to develop optimization technique of warm shrink fitting process and verified its reliability through the experimental results measured in the field and FEM, that is, thermal-structural coupled field analysis. Actual loads measured in the field have a good agreement with the results obtained by theoretical and finite element analysis and also the expanded amounts of the outer diameters of the gears have a good agreement with results.