• Advances in pediatric surgery
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• v.14 no.1
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• pp.67-74
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• 2008

The usefulness of totally implantable central venous port for long-term intravenous infusion is widely accepted in children. Usually the catheters are placed through the internal or external jugular vein. In case of jugular vein cut-down, two separate incisions are needed for catheter and port respectively. Patients also feel uncomfortable as the catheter run through the neck. However these disadvantages can be overcome by using the cephalic vein (CV). We reviewed our experiences on CV cut-down for totally implantable central venous port in children. From January 2002 to December 2006, 201 patients (M:F=127:74) underwent 218 central venous port insertions. Mean age at operation was 5.9 years (2 months - 19 years). Indications included chemotherapy (N=167), long-term intravenous antibiotics infusion (N=36), and total parenteral nutrition (N=15). CV was selected preferentially. The incision includes the deltopectoral triangle laterally, and both the CV cut-down and port insertion were achieved with a single incision. The number of insertion through external, internal jugular vein, and CV was 77, 66 and 75, respectively. The median age, height and body weight were higher in CV cut-down group. The youngest age for CV cut-down was 8 months, the shortest height was 69 cm and the smallest body weight was 5.9 kg. Of 118 trials of CV cut-down, cut-down was successful in 75 cases (63.6 %). CV was absent in 10 cases(8.4 %) and CV was sacrificed after catheter tip malposition in 10 cases (8.4 %). There was only one complication, in which the catheter was inserted into the minute branch of subclavian artery. The CV cut-down method for totally implantable central venous port was safe and feasible in selected groups of patients in children. In addition, preservation of jugular vein and a more favorable cosmetic effect are other benefits of CV cut-down.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.15-19
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• 2004

Domestic use, or embody program that transmit NMEA protocol using multi port as software and is using because there is no fee and product that develop NMEA protocol Multiplexer, import mounting for foreign climax present. These method is paid or there is problem that must make out special processing part in each application program. Also, each mountings that display NMEA protocol can cause double resources waste and damage etc. because manufacturing firm and platform are different. Can act separatively as single hardware module of reliable processing method and high efficiency to supplement this in this treatise, and because using design of optimized cue, heighten memory efficiency of module, and proposed NMEA protocol Multiplexer that can keep high trustability of Come on, deviation compass, echo sound, mountings of GPS and so on and real time communication that is main input sensor equipment about embodiment.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.5
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• pp.541-548
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• 2013

This paper presents a vector network analysis system for 2-port scattering parameters of microwave devices using some basic microwave instruments/devices such as signal generators, vector voltmeter, directional couplers and frequency mixers. The analytical model and implementation method for scattering parameter measurements - which can replace the vector network analyzers - are presented. The performance of the implemented system is evaluated through 1- and 2-port scattering parameter measurements, respectively. The vector volt signals which determine the scattering parameters are detected in two distinct methods depending on the frequency band of interests; a direct-detection method with a single signal generator and vector voltmeter for relatively low band and a heterodyne method to frequency down-mix associated with an additional signal source as well as frequency mixers for high band are used, respectively. Using these two methods, scattering parameters of UHF and X bands are evaluated and their performances are verified through a comercial vector network analyzer.

• Journal of Korea Port Economic Association
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• v.26 no.3
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• pp.165-174
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• 2010

DEA converts multiple inputs and outputs of a decision unit into a single measure of performance, generally mentioned as relative efficiency. DEA has been applied successfully as a performance evaluation tool in many fields including manufacturing, banks, pharmacies, and hospitals to name a few. This paper applies the input-oriented DEA model, DEA/Window analysis, and Malmquist indices to the 9 regions in Korea to measure the efficiency and productivity. The empirical results show the following findings. First, the super efficiency indicate that efficiency of Group 2 is greater than Group 1. Second, Malmquist indices show that productivity of Group 2 is less than Group 1. Third, DEA/Window of Group2 show that Chungnam is most stable, while Jeonnam is most unstable.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.1
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• pp.129-137
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• 2006

This paper studies the effects of the swirl for the variation of intake port configuration that is key parameters in the flow field of direct injection diesel engines. In-cylinder flow characteristics is known to have significant effects on air-fuel mixing, combustion, and emissions. To investigate the effects of the swirl flow, various rpm(250, 500, 750) and two different intake port were used. And to evaluate the swirl motion in the flow field visualization engine, steady state flow test was conducted. Helical port intake port and SCV(Swirl Control Valve) were selected as the design parameters to increase the swirl flow and parametric study was performed. In the case of non-SCV, intake flow rate and non-dimensional swirl ratio were higher than those of SCV for the swirl head type. So, we could strengthen the swirl in the flow field with the swirl head type and don't using SCV. From the results of steady state flow test, non-swirl head type has the most good advantage for intake flow rate, and also the flow rate could be increased by using the SCV slightly. The effects of the type of engine head on intake air flow capability are dominant with respect to the existence of the SCV. We could measure the qualitative grade of swirl by capturing the scattering signal of microballoon from ICCD camera in the visualization diesel engine.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.4
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• pp.505-513
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• 2000

This study suggests new antenna design for polarization diversity. For dual polarization, two port feeding lines are printed on two separate layers and cross-shaped aperture is located on ground between the substrates. For reducing back radiation, a reflector is attached around $\lambda$/4 behind feeding substrates. For wide bandwidth we use a perturbed patch with saw tooth shaped. This perturbation effect causes reduction of antenna size and also reduction of array size. With the antenna proposed here, $1\times4$ array dual polarization antenna for polarization diversity of PCS base station is built. One single element has as large as 10.3%, 11.3% bandwidths at each port, V.S.W.R less than 1.3 and the isolation is less than -40 dB, also array antenna has 13.2% 12.7% band bandwidth, V.S.W.R less than 1.3 the isolation below -36dB and the XPD of 10 dB.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.4
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• pp.468-480
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• 1993

In this paper, at first, the characteristics of double mode SAW (DMS) resonator are analysed by applying the wave guide model and coupled mode theory to 1-port resonator. The DMS resonators (2-pole), which are arranged in a close, parallel configuration of two identical 1-port resonators on a single plate, and 4-pole DMS filters are designed and fabricated at the center frequency of 150.15 MHz with 3-dB bandwidth of 80 KHz. The empirical design characteristics are obtained from the comparison of experimental and theoretical values resulted from several fabrications, and the narrow bandpass filters are implemented on the basis of the above empirical results, which can be used to mobile communication systems. A ST-cut quartz substrate is selected for the stable temperature-frequence characteristics, and high resolution photolithography is applied to the fabrication of filter to get the fine electrode patterns.

• Journal of Navigation and Port Research
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• v.35 no.6
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• pp.533-538
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• 2011

Recently, Free Trade Area generally moves toward a complex and total zone carrying out the logistics and production function simultaneously. Nevertheless, Free Trade Area of Gwangyang Bay Area performs a traditional logistics function only without a introduction of production function. Therefore, the purpose of this research is to suggest alternatives for strengthening the function of Free Trade Area of Gwangynag port. The main findings of this research is summarized as followings. First, a complex and total Free Trade Area through enhancing a production function is to be established. Second, for an efficient management & operation of Free Trade Area, a cooperative system establishment between Free Trade Areas and a single operation system is necessary.

• Journal of Gastric Cancer
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• v.20 no.4
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• pp.431-441
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• 2020

Purpose: Various studies have indicated that reduced-port robotic gastrectomies are safe and feasible for treating patients with early gastric cancer. However, there have not been any comparative studies conducted that have evaluated patients with clinically advanced gastric cancer. Therefore, we aimed to compare the perioperative outcomes of D2 lymph node dissections during reduced-port robotic distal subtotal gastrectomies (RRDGs) and conventional 5-port laparoscopic distal subtotal gastrectomies (CLDGs). Materials and Methods: We retrospectively evaluated 118 patients with clinically advanced gastric cancer who underwent minimally invasive distal subtotal gastrectomies with D2 lymph node dissections between February 2016 and November 2019. To evaluate the patient data, we performed a 1:1 propensity score matching (PSM) according to age, sex, body mass index, American Society of Anesthesiologists physical status classification score, and clinical T status. The short-term surgical outcomes were also compared between the two groups. Results: The PSM identified 40 pairs of patients who underwent RRDG or CLDG. The RRDG group experienced a significantly longer operation time than the CLDG group (P<0.001), although the RRDG group had significantly less estimated blood loss (P=0.034). The number of retrieved extraperigastric lymph nodes in the RRDG group was significantly higher than that of the CLDG group (P=0.008). The rate of postoperative complications was not significantly different between the two groups (P=0.115). Conclusions: D2 lymph node dissections can be safely performed during RRDGs and the perioperative outcomes appear to be comparable to those of conventional laparoscopic surgeries. Further studies are needed to compare long-term survival outcomes.

• Journal of Veterinary Clinics
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• v.28 no.6
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• pp.555-561
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• 2011

Laparoscopic surgery is a well-established alternative to open surgery across disciplines. However, in veterinary medicine, laparoscopic surgery in dogs was rarely reported because of small abdominal size for multiple ports insertion. The concept of single-incision laparoscopic surgery (SILS) is to perform the entire laparoscopic operation through a single incision rather than conventional multiple small skin incisions. Indirect evidence of potential benefits of SILS, decreases operative morbidity related to reduction in port size, already exists. Therefore, this study was performed to evaluate the safety and feasibility of the modified form of SILS using flexible endoscope in Cholecystectomy before clinical adoption. A 2 cm single periumbilical incision was performed, and flexible endoscope was introduced into the abdominal cavity. A laparoscopic grasper was inserted into the abdominal cavity for the traction of gall bladder. Cystic duct and artery were ligated by 5 mm Hem-o-lok$^{(R)}$. Then, gall bladder was dissected and resected from the liver with 5 mm Autonomy Laparo-Angle Maryland dissector and endoscopic needle knife. Resected gall bladder was wrapped by using specimen pouch and was retrieved through abdominal incision from the cavity. All three gall bladders were successfully removed. Hematological changes were not observed during examination periods. No leakage sign was identified at necropsy. The flexible endoscope, as distinct from conventional rigid laparoscope, allows the visualization from various angles and the wide range of motion, result in less crowding.