• Journal of Korean Society of Steel Construction
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• v.14 no.2
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• pp.311-318
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• 2002

This paper described the ultimate strength and deformation limit of welded T-joints in cold-formed square hollow sections. Previous studies showed that the strength of a T-joint still increases with increasing deformations at a ratio of branch width to chord width (${\beta}$) of below 0.8. Therefore, the strength at a certain deformation (chord flange indentation) limit can be regarded as the ultimate strength of a T-joint. The chord flange failure modes were investigated for the ratio of branch width to chord width (${\beta}$) and the ratio of chord width to chord web thickness (B/T). Experimental results including tests done by Kato proposed a deformation limit of 3%B for $16.7{\leq}B/T{\leq}41.6$ and $0.27{\leq}{\beta}{\leq}0.8$. The strength formula of CIDECT and other researchers were compared with the test results. Finally, the strength formula based on yield-line theory was proposed.

• Journal of IKEEE
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• v.24 no.3
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• pp.838-844
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• 2020

In this paper, we propose an efficient Viterbi processor using Joint Viterbi detection and decoding (JVDD) algorithm for a for bluetooth low energy (BLE) system. Since the convolutional coded Gaussian minimum-shift keying (GMSK) signal is specified in the BLE 5.0 standard, two Viterbi processors are needed for detection and decoding. However, the proposed JVDD scheme uses only one Viterbi processor by modifying the branch metric with inter-symbol interference information from GMSK modulation; therefore, the hardware complexity can be significantly reduced without performance degradation. Low-latency and low-complexity hardware architecture for the proposed JVDD algorithm was proposed, which makes Viterbi decoding completed within one clock cycle. Viterbi Processor RTL synthesis results on a GF55nm process show that the gate count is 12K and the memory unit and the initial latency is reduced by 33% compared to the modified state exchange (MSE).

• Journal of Korean Neurosurgical Society
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• v.56 no.4
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• pp.338-343
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• 2014

Objective : The aim of this study is to evaluate the clinical results of endoscopic radiofrequency ablation of medial branch in patients with chronic low back pain originating from facet joints. Methods : Between October 2010 and December 2013, 52 consecutive patients had suffering from chronic low back pain had undergone endoscopic radiofrequency denervation of medial branch of dorsal ramus. The clinical outcomes of these 52 patients were reviewed retrospectively. Preoperative and postoperative Visual Analogue Scale (VAS) and Korean version of Oswestry Disability Index (K-ODI), and patients' satisfaction with the procedure were assessed. Results : The pain scores on the VAS for back pain had improved significantly from a preoperative mean of 7.1 to a postoperative mean of 2 at the last follow-up (p<0.001). The clinical outcomes based on the K-ODI had also improved significantly from a preoperative mean of 26.5% to postoperative mean of 7.7% at the last follow-up (p<0.001). 80% of patients were satisfied with the procedure. There were no complications associated with the procedure. Conclusion : Our preliminary results demonstrate that endoscopic radiofrequency denervation of medial branch could be an effective alternative treatment modality for chronic back pain originating from facet joints that provides long-term pain relief.

• Journal of Korean Neurosurgical Society
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• v.38 no.5
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• pp.338-343
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• 2005

Objective : The sacroiliac joint complex is often related with functionally incapacitating pain in old aged people. The purpose of this study is to delineate the investigation strategies and to determine the long-term effect of radiofrequency [RF] neurotomies for pain arising from sacroiliac Joint dysfunction[SIJD]. Methods : Sixteen patients were diagnosed as having chronic pain from SIJD by comparative controlled blocks on L5 dorsal rami, sacroiliac Joints and deep interosseous ligaments. After confirming the positive response [more than 50% of pain relief], sensory stimulation was applied to detect the 'pathological' branches. Subsequently, RF neurotomies were performed on the selected nerve branches. Surgical outcome was graded as successful, moderate improvement, and failure after a 6month follow-up period. Results : Stimulation intensity was 0.45V to elicit pain response in the L5 dorsal rami and lateral sacral branches. The number of RF-lesioned nerve branches was 6per patient. The average number of lesions for each branch was 1.3. Most commonly selected branches were L5 dorsal ramus [88%] and S2-upper division [88%]. Ten patients [63%] reported a successful outcome according to the outcome criteria after 6months of follow-up, and five patients [31%] reported complete relief [100%]. Five patients [31%] showed moderate improvements. One patient reported failure. Conclusion : RF neurotomy of lateral sacral branches is an excellent treatment modality for the pain due to SIJD, provided that comparative controlled block shows a positive response.

• The Journal of the Korean bone and joint tumor society
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• v.8 no.2
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• pp.39-42
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• 2002

We present a case of the patient with early detection of entrapment of inferior branch of the suprascapular nerve caused by multiple ganglion cysts at the spinoglenoid notch of the scapula, recovering from hypotrophy of the infraspinatus muscle and treating successfully after surgical removal of the cysts, and decompression of the nerve.

• Clinical Pain
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• v.20 no.2
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• pp.122-126
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• 2021

When a patient represents pain in foot, physician can easily overlook compression neuropathy of peripheral nerve as it is uncommon. Among nerve entrapment syndrome encountered in the foot, selective compression in lateral branch of deep peroneal nerve (DPN) is rare. We report a case of a patient with pain and dysesthesia in dorsolateral foot which turned out as lateral branch of deep peroneal nerve entrapment syndrome caused by talonavicular joint effusion. We would like to share diagnostic work up flow and conservative treatment courses. This case manifests the importance of the deep peroneal nerve and its branches in clinical setting of pain and ankle instability.

• Transactions on Electrical and Electronic Materials
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• v.2 no.3
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• pp.7-11
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• 2001

Utility boiler operators seeking to gain the greatest economic advantage from their units are faced with three challenges, namely the obligatory light-up fuel costs, the additional expense of supplementary fuel firing should they wish to use a cheaper fuel that may be beyond the original burner manufacturer’s stability and combustion performance assurances and the immediate environmental impact of both. The novel use of plasma arc technology can provide a solution to these challenges. This paper introduces the work being undertaken through a joint collaboration between the EU, Kazahkstan and Russia in order to develop a tried and tested engineering methodology and a mathematical based application and sensitivity analysis approach for the design and optimisation stage of these plasma devices that, as a consequence, their assist in their universal introduction.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1092-1097
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• 2003

S-N fatigue tests were conducted to investigate the fatigue strength of small diameter socket and butt welded joints made of carbon steels. Experimental parameters were pipe diameter, throat depth, shape of socket welds and welding procedure. Filler metals used in SMAW and GTAW procedure were E9016-G with diameter of 4.0 mm and ER70S-G with diameter of 2.4 mm. API 5L Gr.B pipes were adopted as a small diameter branch pipes. All socket fittings were machined from ASTM A105 carbon steel. Tensile strength was not affected by the welding procedure. Fatigue strength in socket weld joints increased with increasing pipe diameter, area of weld metal and weld leg length of pipe side.

• Safety and Health at Work
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• v.7 no.2
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• pp.111-119
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• 2016

Background: Shift work and/or sleep quality may affect health. We investigated whether shift work and sleep quality, separately and jointly, were associated with abnormal levels of triglycerides, total cholesterol (TC), and low-and high-density lipoprotein cholesterol in 360 police officers (27.5% women). Methods: Triglycerides, TC, and high-density lipoprotein were analyzed on the Abbott Architect; low-density lipoprotein was calculated. Shift work was assessed using City of Buffalo payroll work history records. Sleep quality (good, ${\leq}5$; intermediate, 6-8; poor, ${\geq}9$) was assessed using the Pittsburgh Sleep Quality Index questionnaire. A shift work + sleep quality variable was created: day plus good sleep; day plus poor sleep; afternoon/night plus good; and poor sleep quality. Mean values of lipid biomarkers were compared across categories of the exposures using analysis of variance/analysis of covariance. Results: Shift work was not significantly associated with lipids. However, as sleep quality worsened, mean levels of triglycerides and TC gradually increased but only among female officers (age- and race-adjusted p = 0.013 and 0.030, respectively). Age significantly modified the association between sleep quality and TC. Among officers ${\geq}40$ years old, those reporting poor sleep quality had a significantly higher mean level of TC ($202.9{\pm}3.7mg/dL$) compared with those reporting good sleep quality ($190.6{\pm}4.0mg/dL$) (gender- and race-adjusted p = 0.010). Female officers who worked the day shift and also reported good sleep quality had the lowest mean level of TC compared with women in the other three categories (p = 0.014). Conclusion: Sleep quality and its combined influence with shift work may play a role in the alteration of some lipid measures.

• Proceedings of the KWS Conference
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• 2003.11a
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• pp.191-193
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• 2003

S-N fatigue tests were conducted to investigate the fatigue strength of the small diameter socket and butt welded joints of carbon steels. Experimental parameters were pipe diameter, throat depth, shape of socket welds and welding procedure. Filler metals used in SMAW and GTAW procedure were E9016-G with diameter of 4.0 mm and ER70S-G with diameter of 2.4 m. API 5L Gr.B pipes were adopted as a small diameter branch pipes. All socket fittings were machined from ASTM A105 carbon steel. Fatigue strength in socket weld joints increased with increasing pipe diameter, area of weld metal and weld leg length of pipe side.