• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.6 s.360
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• pp.31-39
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• 2007

In this paper, a system for real-time or periodic measurement and analysis of RF parameters such as forward transmit power and pilot power in CDMA base station systems is proposed. Such RF characteristic parameter measurement can be prevented from system fault and used to achieve optimal service quality and maximum investment return through cell coverage expansion, subscriber capacity increase and so on. For forward power measurement, the local oscillator frequency for the detector is varied so that the transmit power for all channels can be measured. The channel power measurement can be used to analyze the variation in transmit power for changes in voice traffic. By comparing to forward $E_c/I_o$, the pilot channel power can be deducted, which can be used to determine uy degradation in transmit section modules such as the high dover amplifier. Since an accurate analysis of carefully measured data using the CDMA level detector must be made, the system is designed so that measurement errors due to changes in crest factor with modulation method can be overcome.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.139-145
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• 2010

An integrity testing for stone columns was attempted using crosshole S-wave logging. The method is conceptionally quite similar to the crosshole sonic logging (CSL) for drilled piers. The critical difference in the logging is the use of S-wave rather than P-wave, which is used in CSL, because swave is the only wave sensing the stiffness of slower unbounded materials than water. An electro-mechanical source, which can generate reversed Swave signals, was utilized in the logging. The stone column was delineated using the S-wave travel times across the stone column, the S-wave velocity profile of the crushed stone($V_{cs}$-profile) and that of surrounding soil($V_s$-profile). In the calculation of $V_{cs}$-profile of the crushed stone, its friction angle and Ko (coefficient of lateral earth pressure at rest) are recommended to be used. The calculation of the column diameter is not much affected by the values of friction angle and Ko.

• Korean Journal of Acupuncture
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• v.35 no.4
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• pp.239-246
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• 2018

Objective : This case study reports the therapeutic effect of Korean Medicine (KM) treatments including CS(care special pain) and BV(bee venom) pharmacopuncture on herniated intervertebral disc(HIVD) of lumbar spine(L-spine). Methods : Two patients diagnosed with HIVD of L-spine were treated with CS and BV pharmacopuncture on GV3 and EX-B2, acupuncture, cupping, and herbal medicine. The Numeric Rating Scale(NRS), the Oswestry low back pain Disablility Index(ODI) and the Roland Morris Disability Questionnaire(RMDQ) scores were evaluated before and after treatment for comparison. Results : Low back pain(LBP) and radiating pain was improved with a decrease in patients' NRS, ODI and RMDQ scores. Conclusion : These results suggest that KM treatments including combined CS and BV pharmacopuncture could be an effective treatment on patients with HIVD of L-Spine.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2C
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• pp.125-131
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• 2008

Ground stiffness(shear wave velocity) is one of the key parameters in geotechnical earthquake engineering. An In-situ seismic technique has its own advantages and disadvantages over the others in stiffness measurements. By combining the crosshole and seismic cone techniques and utilizing favourable features of bender elements, a new hybrid probe has been developed in order to enhance data quality and easiness of testing. The basic structure of the probe, called "MudFork" is a fork composed of two blades, on each of which source and receiver bender elements were mounted respectively. To evaluate the disturbance caused by the penetration of the probe, shear wave velocity measurements were carried out in the Kaolinite slurry in the laboratory. Finally, the probe was penetrated in coastal mud near Incheon, Korea, using SPT(standard penetration test)rods pushed with a routine boring machine and shear wave velocity measurements were carried out. The results were verified with data from laboratory and cone testing. The performance of the probe turns out to be excellent in terms of data quality and testing convenience.

• The Journal of the Acoustical Society of Korea
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• v.26 no.1
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• pp.42-47
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• 2007

In this paper. we have studied improvement in sensitivity by increasing the frequency of SAW sensors for detecting the immobilization and hybridization of DNA. The sensor consists of twin SAW delay lines operating at 200MHz, a sensing channel and a reference channel. fabricated on $36^{\circ}$ rotated Y-cut X-propagation $LiTaO_3$ crystals. The optimum concentration of probe and target DNA was decided for the improvement of detection mechanism. and digital syringe pump system was used to reduce the human errors. The hybridization between immobilized probe DNA and target DNA on the gold-coated delay line results in mass loading on the delay line of the sensing channel. Thus, the relative frequency change was monitored in relation to the mass loading. The measurement results showed a good response of the sensor to the DNA hybridization with a maximum sensitivity level up to 0.066ng/m1/Hz.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.5 s.347
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• pp.59-67
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• 2006

We demonstrate bidirectional long-reach 35-channel dense wavelength division multiplexing-passive optical network(DWDM-PON) based on wavelength-locked Fabry-Perot laser diodes (F-P LDs). The mode control of F-P LD enhances output power at decreased the required injection power. We show packet-loss-free transmission in all 70 channels at 125 Mb/s per channel line rate through 70 km of single mode fiber without optical amplifier The DWDM-PON can consolidate a metro network into an access network by bypassing the central offices within its reach. The proposed DWDM-PON can accommodate about 80 subscribers with an EDFA-based broadband light source. Further expansion up to 100 subscribers is possible with a semiconductor-based BLS.

• Journal of the Korean Society of Safety
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• v.23 no.3
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• pp.79-86
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• 2008

In the manufacturing industries using HDI(hexamethylene diisocyanate) product hardeners, exposure to HDI is common to spray painters in terms of inhalation and dermal or ocular contact. Due to a lack of information for spray painters in automobile and furniture industries, a questionnaire survey was conducted for the prevalence of adverse health symptoms(33 spray painters and an unexposed group n = 91) to assess the importance of personal controls. Despite the small sample size, common health symptoms were reported, such as skin symptoms(dry cracked skin-61% and dermatitis/skin irritation-33%) and respiratory symptoms(phlegm-49%, asthma-21%). In addition, other adverse health symptoms were reported, such as skin rash(12%), cough(39%), shortness of breath with wheezing(30%), chest tightness and difficulty in breathing(30%). No significant eye symptoms were reported. It was founded that the adverse health symptoms reported in this study were related to poor personal work practices and inappropriate PPE use. Therefore, appropriate personal controls like PPE use, work practices, regular training and education are suggested to minimize the risk of health symptoms. In addition, medical examination will also be suggested for individual health effects.

• Pediatric Infection and Vaccine
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• v.14 no.2
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• pp.129-135
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• 2007

Purpose : Kikuchi disease is a subacute necrotizing lymphadenitis characterized by fever, cervical lymphadenopathy and benign self-limiting course in young women especially, but rare in children. Their etiopathology is still unknown, but involved viruses and autoimmune mechanism were proposed. We investigated the clinical and laboratory characteristics of Kikuchi disease in children. Methods : Five patients were diagnosed of Kikuchi disease from January 2001 to June 2006 in Kyunghee University Hospital. We reviewed their medical records retrospectively and analyzed clinical and laboratory findings. Results : The mean age of 5 patients (male to female ratio; 2:3) was 9 yr 9 mon(range: 8 yr 2 mon-12 yr 6 mon). The chief complaints were sustained fever and cervical lymph node that was unilateral, tender and swollen. All patients were treated with antibiotics before diagnosis was made, and rash developed in 2 patients. One patient showed necrotic change in ultrasound with which we suspected Kikuchi disease. Three patients were examined by CT scan additionally. The interval between admission and cervical lymph node excisional biopsy ranged from 6 days to 15 days, and mean period was 9.6 days. All pathological findings were compatible to necrotizing lymphandenitis. Conclusion : Unnecessary laboratory and imaging studies, and treatment with antibiotics tend to be done before making diagnosis, and that caused prolonged hospitalization. Therefore we studied the clinical and laboratory characteristics of Kikuchi disease in children.

• Radiation Oncology Journal
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• v.6 no.2
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• pp.247-251
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• 1988

Total body irradiation has been applied to treat acute leukemia and chronic granulocytic leukemia.20 patients with acute leukemia or chronic granulocytic leukemia were treated with total body irradiation using 6 MV linear accelerator before bone marrow transplantation at the Division of Therapeutic Radiology, Department of Radiology, St. Mary's Hospital, Catholic University Medical College from August 1987 to September 1988. Among 20 patients, 8 patients received 6 fractions of 200 cGy (total 1200 cGy),10 patients received a single 850 cGy radiation,1 patient received 4 fractions totalling 850 cGy (200, 200, 200, 250), and 1 patient received 1100 cGy in 2 fractions (850, 250).17 patients received allogenic grafts, 2 patients received autologous grafts, and only one patient received one locus mismatched graft. 13 patients are still alive and 7 patients died. The complications induced by total body irradiation were nausea and vomiting, diarrhea, skin erruption, mucositis, and pneumonitis.

• Clinical and Experimental Pediatrics
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• v.46 no.9
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• pp.898-902
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• 2003

Purpose : To determine the clinical association of diagnostic criteria and the prevalence of autoantibodies in newly diagnosed children with juvenile dermatomyositis(JDM). Methods : Thirty-two children with JDM were identified at Seoul National University Children's Hospital from March 1985 to March 1999 by retrospective review. The diagnosis of JDM was based on the criteria proposed by Bohan and Peter. We investigated for the presence of several autoantibodies: antinuclear(ANA), double-stranded DNA, anti-Sm, anti-ribonucleoprotein(RNP), anti-SSA/ SSB, anti-Jo1, anti-Scl-70 antibodies and rheumatoid factor(RF). Results : Sex ratio and age at diagnosis were similar to data published in other studies. All the newly diagnosed children with JDM had a typical rash(100%) and proximal muscle weakness(100%); 17(53%) had muscle pain or tenderness; 10(31%) calcinosis; eight(25%) dysphagia; eight(25%) arthritis, and seven(22%) fever. Muscle enzymes were elevated in 90% of the patients. Of the 27 patients who had an electromyogram, 20(70%) had diagnostic results. Sixteen(70%) of biopsied patients had appropriated results for JDM. Patients were negative for all autoantibodies except ANA and RF. ANA and RF were detected in 47% and 7% of the patients respectively. Conclusion : Although the sensitivity of the criteria proposed by Bohan and Peter is superior, each of these criteria has possible confounding factors. Additional criteria may be needed for early diagnosis of JDM. Based on our findings of autoantibodies in JDM, we do not recommend routine testing for autoantibodies in children with typical JDM.