• Journal of the Korean Society for Railway
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• v.14 no.5
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• pp.433-441
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• 2011

It is a fact that the straightening of track alignment is one of the undoubted ways to improve the train speed on conventional lines, while that requires huge investment resources. Therefore, the operation of a tilting train as well as the minimum improvement of track is suggested as an effective and economical alternative way for the speed-up of conventional lines. Since a driving mechanism of tilting train is different from those of existing trains, in order to make sure its operation safety and stability on conventional line, the performance of track and roadbed must be preferentially evaluated on the conventional line. Furthermore, it is necessary to estimate the tilting-train-induced roadbed response in detail since the roadbed settlement can lead to the track deformation and even derailment. In this research, the patterns of wheel load and lateral force were monitored and analyzed through the field tests, and the derailment coefficient and degree of wheel off-loading were calculated in order to evaluate the tilting train running safety depending on the running speeds (120km~180km) on the conventional line. Moreover, roadbed pressure, settlement and acceleration were also observed as tilting-train-induced roadbed responses in order to estimate the roadbed stability depending on the running speeds. Consequently, the measured derailment coefficient and degree of wheel off-loading were satisfied with their own required limits, and all of the roadbed responses were less than those of existing high-speed train (KTX) over an entire running speed range considered in this study. As a result of this study, the tilting train which will be operated in combination with existing trains is expected to give no adverse impact on the conventional line even with its improved running speed.

• Journal of Acupuncture Research
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• v.18 no.5
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• pp.60-69
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• 2001

Objective : Recent studies Suggested that there is a strong correlation between acupuncture stimulation and its related cortical activation. Anther study showed that either positive or negative BOLD effects could be observed depending on anatomical structure in acupuncture. Material and Methods : 1) Subjects and paradigms : Two separate stimulation paradigms were performed on five healthy (aged 22-23 yrs) in this study. First, the paradigm of acupuncture stimulation was that the acupuncture needle was inserted in acupoints KI6(照海), which is located in lateral side of the foot and then continuously twisted(補瀉를 除外한 捻轉法) for 70 seconds for 10 cycles of activation. During rest period (70 seconds), the needle was completed removed from acupoint. Total 60 cycles were performed and 10 images were obtained per cycle. Second, non-acupoint was randomly selected and the same paradigm was performed as acupoint stimulation. The stimulation protocol comprised 10 cycles of alternating activation and rest (10 images per cycle). Total 60 cycles were performed and each cycle take about 1.5 sec for motor task. Subjects take an at least 15 minutes break before starting anther paradigm. Conclusion : In this study, I investigated a new acupoint KI6(照海) which was known as motor - related acupoint and obtained an evidence that the stimulation of KI6(照海) resulted in negative BOLD response to stimulation.

• Journal of the Korean GEO-environmental Society
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• v.13 no.6
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• pp.91-100
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• 2012

Wireless monitoring system for the structural health evaluation has a limit to the reliability of measured response. The objective of this study is to evaluate an effective measurement range of the wireless monitoring system on the analyzed data. For the wireless monitoring system, Bluetooth and Wi-Fi are applied to datalogger-receiver and receiver-personal computer, respectively. For the model of the monopile structure response, a laboratory-scale monopile is manufactured with Mono Cast Nylon and a lateral loading is applied by hammer impacting. Strain gauges attached on the model monopile are connected with the datalogger. The distances of datalogger-receiver and receiver-personal computer are changed for the evaluation of the measurement range. Experimental results show that the receiving rates of the response remain almost constant within limited distance, while the receiving rates dramatically decrease out of effective range. In addition, the receiving rates affect on the measured natural frequencies of the model monopile. This study suggests that the effective range evaluation of the wireless monitoring system may be used for the determination of a monitoring distance to the monopile installed in the offshore wind farm.

• Journal of the Korean Geotechnical Society
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• v.15 no.3
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• pp.83-97
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• 1999

This paper presents the results of a parametric study on the interaction between buried pipes and surface load using the finite element method of analysis. A series of laboratory model tests were also performed in order to validate the adopted finite element model and to capture essential features of the physical behavior of buried pipes subjected to surface load. In the parametric study, a wide range of boundary conditions were analyzed with emphasis on the response of the buried pipes to surface load. The results of analysis such as contact stress distribution at the soil/pipe interface and axial thrust of the pipe were thoroughly analyzed, and a database on the response of buried pipe under surface load was established for future development of a semi-empirical design/analysis method. The results indicated that the degree of interaction between buried pipes and surface load significantly varies with the vertical and lateral location of pipe with respect to surface load, and that the current design method, which does not consider soil-structure interaction, cannot correctly capture the pipe response to surface loading. Furthermore, based on the results of analysis, a semi-empirical equation was suggested, which estimates the maximum pipe thrust due to surface load for flexible buried pipes.

• Journal of the Korean Geotechnical Society
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• v.34 no.8
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• pp.37-49
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• 2018

Since the observation of ground motions in South Korea, liquefaction manifestation was the first to be observed in Pohang earthquake in 2017 with $M_L$ 5.4. Because liquefaction causes ground settlement and lateral spread damaging in-ground or super structures, various researchers have been analyzing the Pohang liquefaction case history to better understand and predict liquefaction consequence and to prevent future disasters. In prior research at the 2018 EESK conference, a map of Liquefaction Potential Index (LPI), indicating the severity of liquefaction, in Pohang was created and compared with damage observations. The LPI correlated well with the observations, but the severity categorized by LPI range was significantly higher than the actual observations in most regions. The prior LPI map was created evaluating ground motions using the simplified approach. In this research, we perform the effective site response analyses with porewater pressure generation model for the detailed evaluation of liquefaction on the liquefied sites in Pohang. We found that the simplified approach for LPI evaluation can overestimate the severity.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.130-138
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• 2002

Purpose : This study analyzed the prognostic factors affecting the survival rate and evaluated the role of radiation therapy in muscle-invading bladder cancer. Materials and Methods : Twenty eight patients with bladder cancer who completed planned definitive radiotherapy in the Departments of Therapeutic Radiology and Urology, Chonnam National University Hospital between Jan. 1986 to Dec. 1998 were retrospectively analyzed. The reviews were peformed based on the patients' medical records. There were 21 males and 7 females in this study. The median of age was 72 years old ranging from 49 to 84 years. All patients were confirmed as having transitional cell carcinoma with histological grade 1 in one patient, grade 2 in 15, grade 3 in 9, and uninformed in 3. Radiation therapy was peformed using a linear accelerator with 6 or 10 MV X-rays. Radiation was delivered daily with a 1.8 or 2.0 Gy fraction size by 4 ports (anterior-posterior, both lateral, alternatively) or 3 ports (Anterior and both lateral). The median radiation dose delivered to the isocenter of the target volume was 61.24 Gy ranging from 59 to 66.6 Gy. The survival rate was calculated by the Kaplan-Meier method. Multivariate analysis was peformed on the prognostic factors affecting the survival rate. Results : The survival rate was $76\%,\;46\%,\;33\%,\;33\%$ at 1, 2, 3, 5 years, respectively, with 19 months of median survival. The potential factors of age (less than 70 years vs above 70), sex, diabetes mellitus, hypertension, hydronephrosis, 1-stage (T3a vs T3b), TUR, chemotherapy, total duration of radiotherapy, radiation dose (less than 60 Gy vs above 60 Gy), and the treatment response were investigated with uniand multivariate analysis. Un univariate analysis, the T-stage (p=0.078) and radiation dose (p=0.051) were marginally significant, and the treatment response (p=0.011) was a statistically significant factor on the survival rate. Multivariate analysis showed there were no significant prognostic factors affecting the survival rate. Conclusion : The treatment response and radiation dose are suggested as th은 statistically significant factors affecting the survival rate of muscle invasive bladder cancer. A Further prospective randomized study is needed to confirm these prognostic factors.

• Journal of the Korean Geosynthetics Society
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• v.13 no.1
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• pp.71-83
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• 2014

Busan is located at the mouth of Nakdong River and if an earthquake occurs, it is very likely that the damage by the earthquake will be worse as liquefaction can happen in the sand layer, builtup soil, and landfill ground due to amplification in the lower sedimentary layer that is well developed in the river mouth. Therefore, this study first examined the possibility of liquefaction in the replaced sand layer under breakwater using 14 earthquakes in 5.6-7.9 scale and artificial earthquakes including the seismic wave suggested in the standard specifications for seismic design of ports and fishing port facilities to evaluate the stability of breakwater which is the primary protective structure for port facilities against earthquakes. Second, analysis on characteristics of the seismic energy and acceleration response spectrum by size of earthquake was performed to suggest the most appropriate size of seismic wave for the condition in Korea. Third, finite element analysis was performed using the suggested seismic wave to study the characteristics of earthquake by finding the dynamic lateral displacement of breakwater and verifying the stability of structure and the displacement and forces occurring at geotextile. Results of the study showed that the possibility of liquefaction in the landfill and replaced sand layer, the dynamic lateral displacement of breakwater, and changes of geotextile are greatly affected by the subsurface ground (replaced sand layer).

• Journal of Korean Neurosurgical Society
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• v.51 no.6
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• pp.363-366
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• 2012

Objective : Meralgia paresthetica (MP) is a syndrome of pain and/or dysesthesia in the anterolateral thigh that is caused by an entrapment of the lateral femoral cutaneous nerve (LFCN) at its pelvic exit. Despite early accounts of MP, there is still no consensus concerning the effectiveness of neurolysis or transaction treatments in the long-term relief for medically refractory patients with MP. We retrospectively analyzed available long-term results of LFCN neurolysis for medically refractory MP in an effort to clarify this issue. Methods : During the last 7 years, 11 patients who had neurolysis for MP were enrolled in this study. Nerve entrapment was confirmed preoperatively by electrophysiological studies or a positive response to local anesthetic injection. Decompression of the LFCN was performed at the level of the iliac fascia, inguinal ligament, and fascia of the thigh distally. The outcome of surgery was assessed 8 weeks after the procedure followed at regular intervals if symptoms persisted. Results : Twelve decompression procedures were performed in 11 patients over a 7-year period. The average duration of symptoms was 8.5 months (range, 4-15 months). The average follow-up period was 33 months (range, 12-60 months). Complete and partial symptom improvement were noted in nine (81.8%) and two (18.2%) cases, respectively. No recurrence was reported. Conclusion : Neurolysis of the LFCN can provide adequate pain relief with minimal complications for medically refractory MP. To achieve a good outcome in neurolysis for MP, an accurate diagnosis with careful examination and repeated blocks of the LFCN, along with electrodiagnosis seems to be essential. Possible variation in the course of the LFCN and thorough decompression along the course of the LFCN should be kept in mind in planning decompression surgery for MP.

• Journal of Industrial Convergence
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• v.17 no.4
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• pp.77-86
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• 2019

The purpose of this study was to identify the effect of Home Health Nursing based Respiratory Management Program (HHNbRMP) on unmet healthcare need and healthcare resource utilizations of patients applying the home mechanical ventilator in the home with amyotrophic lateral sclerosis. The subjects of this study were 40 patients placed in an experimental group(n=19) and a control group(n=21), respectively. This HHNbRMP based on Cox's interaction model was consisted of cognitive assent (education, specialized medical care, case management), internal motivation (airway clearance, thoracic and air accumulated exercise) and psychological response (meditation & active listening). The intervention was applied to experimental group during 12 weeks. As variables was measured at baseline, twelve, twenty-four weeks and healthcare unmet need, resource utilizations (admission, out patient department, emergency room) was measured at 24 weeks. The data were analyzed by t-test, ANOVA and Repeated Measures ANCOVA. This intervention was not effective the unmet healthcare need. But the admission in to the hospital among the healthcare resource utilizations variables showed a significant difference at twenty-four weeks(t=4.17, p=.049). This results suggest that applying this program tailored to patients condition, utility of medical resource would be decreased, specially admission.

• Journal of Korean Society of Steel Construction
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• v.22 no.4
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• pp.325-334
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• 2010

In this study, an unbraced five-story steel-framed structure was designed in accordance with KBC2005 to understand the features of structural behavior for the arrangement of semi-rigid connections. A pushover analysis of the structural models was performed, wherein all the connections were idealized as fully rigid and semi-rigid. Additionally, horizontal and vertical arrangements of the semi-rigid connection were adopted for the models. A fiber model was utilized for the moment-curvature relationship of the steel beam and the column, and a three-parameter power model was adopted for the moment-rotation angle of the semi-rigid connection. The top displacement, base-shear force, required ductility for the connection, sequence of the plastic hinge, and design factors such as the overstrength factor, ductility factor, and response modification coefficient were investigated using the pushover analysis of a 2D structure subjected to the equivalent static lateral force of KBC2005. The partial arrangement of the semi-rigid connection was found to have secured higher strength and lateral stiffness than that of the A-Semi frame, and greater ductility than the A-Rigid frame. The TSD connection was found suitable for use for economy and safety in the sample structure.