• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.11
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• pp.1940-1945
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• 2006

The small and wideband annular ring slot antenna with eccentric radiating structure and low impedance feedline is presented. This antenna is analyzed by using substrate with permittivity 4.3 and thickness 1mm. As the measured impedance bandwidth of proposed antenna is $118%(S_{11}{\leq}-10dB)$, its bandwidth is much broader than that of conventional annular ring slot antenna.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.1
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• pp.110-116
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• 2012

This paper proposes a new diversity antenna which is the base of MIMO, tunable and reconfigurable antennas. The antenna has a small size and high inter-antenna isolation resulting from the compact radiating element comprising a meandered line and an open-loop combined in one limited uniplanar space and a modified T-shaped decoupling structure, respectively. In a WiMAX band, the radiating element and the entire antenna are $0.092{\lambda}$ and $0.2216{\lambda}$ in size, which shows effective size-reduction and the gain and efficiency of the proposed antenna attached to the ground of a handheld device are 3.7dBi and 56% acceptable to the industrial standard.

• Journal of Korean Neurosurgical Society
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• v.41 no.6
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• pp.418-420
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• 2007

Discal cyst is a very rare lesion that can result in refractory low back pain and leg radiating pain. Because they are so uncommon, their exact origin and pathophysiology are still unknown. A 31-year-old man visited our institute due to low back pain and severe left leg radiating pain. Magnetic resonance images [MRI] revealed spherically shaped extradural cystic lesion at L2-L3 level. Computed tomography [CT] discography demonstrated obvious communication between the intervertebral disc and the cyst. The patient underwent posterior decompression and excision of cyst. The symptoms were remarkably improved immediately after surgery.

• Journal of IKEEE
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• v.25 no.2
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• pp.408-411
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• 2021

This paper presents a new reflectarray antenna capable with 1-bit switchable capability for W-band beamforming network. The proposed antenna has been optimized using two unit-cells with sizes of 1.0 mm and 1.3 mm to form a total number of 193 radiating elements on a square aperture surface of length 30 mm. These radiating elements are spaced 0.5 wavelengths apart and fed by a 15 dBi pyramidal horn antenna as the feed antenna placed 53 mm away from the aperture center. The proposed reflectarray achieves a realized peak gain of 22.52 dBi, a half-power beamwidth of 5.1° in both E- and H-planes at the test frequency of 80 GHz and operates over a wide bandwidth from 74 GHz to 90 GHz.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.1
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• pp.45-51
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• 2008

This paper presents theoretical and experimental analysis on the characteristics of the power spectrum of electormagnetic waves radiating from the spark plug and their cables of a distributorless ignition system. The theoretical study was conducted applying the microwave transmission line theory and the antenna theory. The experimental works were carried out to measure the standing wave ratio(SWR) and the radiation power spectrum of this system. As a result, it has been found that a spark plug and its cable is working as a monopole antenna radiating elelctromagnetic waves. Because of its similar structure to a monopole antenna, the envelope of radiation power spectrum distribution has a bell shape which can be obtained from a monopole antenna operating as a series resonant circuit. The frequency characteristics from the SWR measurements show a similar frequency characteristics of power spectrum of the system studied. Also, it has been found that the density of the power spectrum of the system fitting a long time used spark plug is higher than that of fitting a new spark plug.

• Journal of Korean Neurosurgical Society
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• v.40 no.4
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• pp.256-261
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• 2006

Objective : The goal of this study was to establish the benefit and prognostic factors of lumbar medial branch block[MBB] for low back pain. Methods : A retrospective analysis was based on the data obtained from 281 patients with low back pain, who visited our hospital between January 2001 and November 2004. Pain relief was evaluated at 2 weeks, 1 month and 3 months. The authors analyzed the results of MBB according to the patient's age, sex, symptom duration, pathologic condition, and presence of radiating pain. Results : Two hundred eighty one patients had sprain [151]. lumbar fracture [27], spinal stenosis [50], herniated lumbar disc [24] acute post-operative pain [8], and chronic post-operative pain [21] with success rate of 63.6%, 59.3%, 26.0%, 25.0%, 87.5% and 42.9%, respectively. The effects of MBB in sprain, lumbar fracture, and acute post-operative pain were significantly better than those in stenosis, herniated lumbar disc and chronic post-operative pain patients. The patients in young age group [<60 years], with short symptom duration [<6 months] and without radiating pain showed good response to lumbar MBB. Conclusion : The lumbar MBB appears to be safe and effective for low back pain in certain selected patients. Good prognostic factors were low back pain without surgical conditions and radiating pain, with short symptom duration [<6 months], and in relatively young age [<60 years] group.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.1
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• pp.81-88
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• 2011

This paper presents a design of spiral antenna with broad bandwidth for non-linear junction detector(NLJD). An elliptical patch as radiating element located on center position of radiating surface, as well as the spiral elements on radiating surface was designed for broad bandwidth of spiral antenna. An antenna ground structure generating the multi resonance by spiral slit inserted on ground surface was also proposed. In order to realize high directivity and high gain of the proposed antenna, the cavity wall made of Fr4-epoxy and the metal cap were considered in design. As a result, the calculated gain of antenna with metal cap was improved about 3 dB with comparison of antenna without metal cap and the measured main beam directivity toward -z axis direction agreed well with calculation result. The measured axial ratio satisfied the circular polarization within -z axis ${\pm}45^{\circ}$ at design frequency bands and showed reasonable agreement with prediction.

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.1
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• pp.66-72
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• 2016

This retrospective observational study was aimed to assess that Shinchubogun-tang (Shenzhuibujian-tang ; SBT) improves the symptoms related to lumbar disc herniation. We analyzed the medical records of 36 patients, who were satisfied with inclusion and exclusion criteria. The patients were diagnosed with lumbar disc herniation and prescribed with SBT in addition to Korean medical common treatments at Dunsan Korean Medicine Hospital of Daejeon University from January 1st, 2013 to November 30th, 2015. The effects of SBT was evaluated by comparing before and after taking SBT through 0-10 visual analogue scale(VAS) of the symptoms including lower back pain, radiating pain, and lower extremity numbness. The average period of common Korean medicine treatment before SBT prescription was 9.78 days and then the patients received SBT along with common Korean medicine treatment for 13.17 days on average. SBT plus common korean medicine treatment group significantly decreased VAS score of lower back pain from 5.40±1.62 to 3.28±1.70 (p<0.01), radiating pain from 5.60±1.42 to 2.35±1.79 (p<0.01), lower extremity numbness from 5.77±1.52 to 2.55±1.85(p<0.01). These results demonstrated that SBT might have a potential on improvement of lumbar disc herniation by reducing the symptoms of lower back pain, radiating pain, and lower extremity numbness.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.8 no.1
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• pp.15-26
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• 2013

Objectives: The purpose of this study is to find out the relationship between lumbar lordotic angle and low back pain patterns. Methods: We randomly selected the 1191 patients (595 males, 596 females) who have visited Bu-Chun Jaseng Hospital of Korean Medicine with low back pain. We have taken lumbar x-ray films and measured their lumbar lordotic angle, the angle formed between L1 superior margin and S1 superior margin. We investigated 1191 patients' low back pain patterns(date of occurence, existence of radiating pain, trend of increasing pain with lumbar extention and flexion, trend of increasing pain with standing and sitting positions) and analysed the relationship between lumbar lordotic angle and low back pain patterns. Results: 1. The lumbar lordotic angle of the acute phase patient is more straight than the chronic one. 2. The lumbar lordotic angle of the patients with radiating pain is more straight than the patients without radiating pain. 3. At acute phase, the lumbar lordotic angle of the patients with increasing pain from lumbar extention is more straight than those with increasing pain from lumbar flexion. 4. At chronic phase, the lumbar lordotic angle of the patients with increasing pain from lumbar flexion is more straight than those with increasing pain from lumbar extention. Conclusions: There was a significant correlation between lumbar lordotic angle and low back pain.

• Journal of Acupuncture Research
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• v.27 no.5
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• pp.79-87
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• 2010

Objectives : This study was designed to evaluate the effects of treatment of HIVD patients with lower back pain, lower limb radiating pain and restricted on SLRT by the Sa-Am acupuncture. Methods : From March 2010 to July 2010, thirty HIVD patients who admitted to Cheonan oriental medical hospital in Daejeon university were divided into two groups. Group I was treated by Sa-Am acupuncture Banggwangjeonggyeok and general acupuncture, Group II by general acupuncture. We evaluated the treatment effect of each group with the Visual Analog Scale(VAS), Oswestry Disability Index(ODI), SLR test, dividing two period(from admission day to third day after admission and from third day to sixth day after admission). Results : 1. Group I is more effective than Group II in early pain and reducing rate of pain. 2. Group I is more effective than Group II in ODI score reducing rate from admission day to third day after admission, but there was no significant difference between the two groups from third day to sixth day after admission. 3. Group I is more effective than Group II in early SLR test improvement rate. Conclusions : Sa-Am acupuncture Banggwangjeonggyeok on HIVD patients with lower back pain, lower limb radiating pain and restricted on SLR test was effective in reducing pain and improving SLR test.