• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.3
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• pp.149-157
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• 2019

The purpose of this study is to investigate the effects of the significant duration of ground motions on responses of base-isolated nuclear power plants (NPPs). Two sets of ground motion records with short duration (SD) and long duration (LD) motions, scaled to match the target response spectrum, are used to perform time-history analyses. The reactor containment building in the Advanced Power Reactor 1400 (APR1400) NPP is numerically modeled using lumped-mass stick elements in SAP2000. Seismic responses of the base-isolated NPP are monitored in forms of lateral displacements, shear forces, floor response spectra of the containment building, and hysteretic energy of the lead rubber bearing (LRB). Fragility curves for different limit states, which are defined based on the shear deformation of the base isolator, are developed. The numerical results reveal that the average seismic responses of base-isolated NPP under SD and LD motion sets were shown to be mostly identical. For PGA larger than 0.4g, the mean deformation of LRB for LD motions was bigger than that for SD ones due to a higher hysteretic energy of LRB produced in LD shakings. Under LD motions, median parameters of fragility functions for three limit states were reduced by 12% to 15% compared to that due to SD motions. This clearly indicates that it is important to select ground motions with both SD and LD proportionally in the seismic evaluation of NPP structures.

• Earthquakes and Structures
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• v.27 no.2
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• pp.143-154
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• 2024

Friction pendulums typically suffer from poor uplift-restraining. To improve the uplift-restraining and enhance the energy dissipation capacity, this article proposed a composite isolation device based on electromagnetic forces. The device was constructed based on a remote control system to achieve semi-active control of the composite isolation device. This article introduces the theory and design of an electromagnetic chuck-friction pendulum system (ECFPS) and derives the theoretical equation for the ECFPS based on Maxwell's electromagnetic attraction equation to construct the proposed model. By conducting 1:3 scale tests on the electromagnetic device, the gaps between the practical, theoretical, and simulation results were analyzed, and the accuracy and effectiveness of the theoretical equation for the ECFPS were investigated. The hysteresis and uplift-restraining performance of ECFPS were analyzed by adjusting the displacement amplitude, vertical load, and input current of the simulation model. The data obtained from the scale test were consistent with the theoretical and simulated data. Notably, the hysteresis area of the ECFPS was 35.11% larger than that of a conventional friction pendulum. Lastly, a six-story planar frame structure was established through SAP2000 for a time history analysis. The isolation performances of ECFPS and FPS were compared. The results revealed that, under horizontal seismic action, the horizontal seismic response of the bottom layer of the ECFPS isolation structure is greater than that of the FPS, the horizontal vibration response of the top layer of the ECFPS isolation structure is smaller than that of the FPS, and the axial force at the bottom of the columns of the ECFPS isolation structure is smaller than that of the FPS isolation structure. Therefore, the reliable uplift-restraining performance is facilitated by the electromagnetic force generated by the device.

• Tuberculosis and Respiratory Diseases
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• v.48 no.5
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• pp.740-747
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• 2000

Background : To compare the efficacies and side effects of etoposide, cisplatin/cyclophosphamide, adriamycin, vincristine(VPP/CAV) with those of carboplatin etoposide(CE) in extensive stage small cell lung cancer patients. Method : Patients with extensive stage small lung cancer who has measurable disease were eligible. VPP/CAV group(n=22) was treated with cisplatin(60mg/$m^2$ iv. D1) etoposide(100mg/$m^2$ iv. D1-3), and 3 weeks later cyclophosphamide(1000mg/$m^2$ iv. D1), adriamycin( 40mg/$m^2$ iv. D1), and vincristine(1.4mg/$m^2$ iv. D1), were administered alternatively. CE group(n=22) was treated with carboplatin(325mg/$m^2$ iv. D1) and etoposide (100mg/$m^2$ iv. D1-3) ; repeated treatment was performed every 3 weeks. Result : Forty four patients were eligible for the study. The overall response rate was 61.4% (complete remission rate 0%, partial response rate 61.4%, stable disease rate 25%, progressive disease rate 13.6%), and median survival was 10.8 months. In VPP/CAV group, response rate was 54.5% (complete remission rate 0%, partial response rate 54.4%, stable disease rate 27.3%, progressive disease rate 18.2%), and, in carboplatin/etoposide group, the response rate was 68.2%(complete remission rate 0%, partial response rate 68.2%, stable disease rate 22.7%, progressive disease rate 9.1%). The median survival time was 9.5 months in the VPP/CAV group and 11 months in CE group. The toxicity of both group was moderate, and anemia was more frequent in the CE group. Conclusion : VPP/CAV regimen and CE regimen produced similar response rates and survival times in extensive stage small cell lung cancer patients. CE regimen may be effective as part of the initial therapy for extensive stage small cell lung cancer.

• Radiation Oncology Journal
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• v.24 no.4
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• pp.223-229
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• 2006

$\underline{Purpose}$: Combined modality therapy including chemotherapy, surgery and radiotherapy is considered the standard of care for the treatment of stage III non-small cell lung cancer (NSCLC). This study was conducted to evaluate the efficacy of paclitaxel and cisplatin with induction chemotherapy followed by concurrent chemoradiotherapy for stage IIIB NSCLC. $\underline{Materials\;and\;Methods}$: Between July 2000 and October 2005, thirty-nine patients with stage IIIB NSCLC were treated with two cycles of induction chemotherapy followed by concurrent chemoradiotherapy. The induction chemotherapy included the administration of paclitaxel ($175\;mg/m^2$) by intravenous infusion on day 1 and treatment with cisplatin ($75\;mg/m^2$) by intravenous infusion on day 1 every 3 weeks. Concurrent chemoradiotherapy included the use of paclitaxel ($60\;mg/m^2$) plus cisplatin ($25\;mg/m^2$) given intravenously for 6 weeks on day 43, 50, 57, 71, 78 and 85. Thoracic radiotherapy was delivered with 1.8 Gy daily fractions to a total dose of $54{\sim}59.4\;Gy$ in $6{\sim}7$ weeks (median: 59.4 Gy). $\underline{Results}$: The follow up period was $6{\sim}63$ months (median: 21 months). After the induction of chemotherapy, 41.0% (16 patients) showed a partial response and 59.0% (23 patients) had stable disease. After concurrent chemoradiotherapy, 10.3% (4 patients) had a complete response, 41.0% (16 patients) had a partial response, and the overall response rate was 51.3% (20 patients). The 1-, 2-, 3-year overall survival rates were 66.7%, 40.6%, and 27.4% respectively, with a median survival time of 20 months. The 1-, 2-, 3-year progression free survival rates were 43.6%, 24.6%, and 24.6%, respectively, with median progression free survival time of 10.7 months. Induction chemotherapy was well tolerated. Among 39 patients who completed the entire treatment including chemoradiotherapy, 46.3% (18 patients) had esophagitis greater than grade 3 and 28.2% (11 patients) had radiation pneumonitis greater than grade 3. $\underline{Conclusion}$: Paclitaxel and cisplatin with induction chemotherapy followed by concurrent chemoradiotherapy for stage IIIB NSCLC seems to be an effective treatment. Occurrence of esophagitis and pneumonitis represents a significant morbidity and suggests a modification of the treatment regimen, either with the chemotherapy schedule or with radiotherapy treatment planning.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.1
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• pp.63-72
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• 2020

The purpose of this study is to investigate the effects of the application of various numerical models and frequency contents of earthquakes on the performances of the reactor containment building (RCB) in a nuclear power plant (NPP) equipped with an advanced power reactor 1400. Two kinds of numerical models are developed to perform time-history analyses: a lumped-mass stick model (LMSM) and a full three-dimensional finite element model (3D FEM). The LMSM is constructed in SAP2000 using conventional beam elements with concentrated masses, whereas the 3D FEM is built in ANSYS using solid elements. Two groups of ground motions considering low- and high-frequency contents are applied in time-history analyses. The low-frequency motions are created by matching their response spectra with the Nuclear Regulatory Commission 1.60 design spectrum, whereas the high-frequency motions are artificially generated with a high-frequency range from 10Hz to 100Hz. Seismic responses are measured in terms of floor response spectra (FRS) at the various elevations of the RCB. The numerical results show that the FRS of the structure under low-frequency motions for two numerical models are highly matched. However, under high-frequency motions, the FRS obtained by the LMSM at a high natural frequency range are significantly different from those of the 3D FEM, and the largest difference is found at the lower elevation of the RCB. By assuming that the 3D FEM approximates responses of the structure accurately, it can be concluded that the LMSM produces a moderate discrepancy at the high-frequency range of the FRS of the RCB.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.213-221
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• 2008

Purpose: The objective of this retrospective study was to identify predictive factors for the complete pathologic response and tumor downstaging after preoperative concurrent chemoradiotherapy for locally advanced rectal cancer. Materials and Methods: Between the years 2000 and 2008, 39 patients with newly diagnosed rectal cancer without prior evidence of distant metastasis received preoperative concurrent chemoradiotherapy followed by surgery. The median radiation dose was 50.4 Gy (range, $45{\sim}59.4\;Gy$)). Thirty-eight patients received concurrent infusional 5-fluorouracil and leucovorin, while one patient received oral capecitabine twice daily during radiotherapy. Results: A complete pathologic response (CR) was demonstrated in 12 of 39 patients (31%), while T-downstaging was observed in 24 of 39 patients (63%). N-downstaging was observed in 18 of 28 patients (64%), with a positive node in the CT scan or ultrasound. Two patients with clinical negative nodes were observed in surgical specimens. The results from a univariate analysis indicated that the tumor circumferential extent was less than 50% (p=0.031). Moreover, the length of the tumor was less than 5 cm (p=0.004), while the post-treatment carcinoembryonic antigen (CEA) levels were less than or equal to 3.0 ng/mL (p=0.015) and were significantly associated with high pathologic CR rates. The univariate analysis also indicated that the adenocarcinoma (p=0.045) and radiation dose greater than or equal to 50 Gy (p=0.021) were significantly associated with high T-downstaging, while a radiotherapy duration of less than or equal to 42 days (p=0.018) was significantly associated with N-downstaging. The results from the multivariate analysis indicated that the lesser circumferential extent of the tumor (hazard ratio [HR] 0.150; p=0.028) and shorter tumor length (HR, 0.084; p=0.005) independently predicted a higher pathologic CR. The multivariate analysis also indicated that a higher radiation dose was significantly associated with higher T-downstaging (HR, 0.115; p=0.025), while the shorter duration of radiotherapy was significantly associated with higher N-downstaging (HR, 0.028; p=0.010). Conclusion: The circumferential extent of the tumor and its length was a predictor for the pathologic CR, while radiation dose and duration of radiotherapy were predictors for tumor downstaging. Hence, these factors may be used to predict outcomes for patients and to develop further treatment guidelines for high-risk patients.

• Tuberculosis and Respiratory Diseases
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• v.58 no.4
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• pp.344-351
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• 2005

Background : Both gemcitabine and vinorelbine are effective anticancer drugs with mild toxicity on non-small cell lung cancer, and monotherapy of these drugs are effective as a second-line chemotherapy. The aim of this trial was to assess the response and toxicity of a combination of gemcitabine and vinorelbine in patients of previously treated for non-small cell lung cancer. Materials and Methods : 24 patients, initial stage III A/B,IV and previously treated with platinium and taxane based regimens, were enrolled from June 2000 to March 2004. The regimens consisted of vinorelbine $25mg/m^2$ followed by an infusion of gemcitabine $1000mg/m^2$ on day 1 and day 8 every three weeks. This course was repeated more than twice. Results : Twenty-four patients were analyzed for the response, survival rate, and toxicities. The overall response was 17% with a complete remission rate of 4%. The median time-to progression (TTP) was 3.1 months (95%, CI 1-10months), and the survival time was 8.2 months (95%, CI 1-23 months). The grade 3/4 toxicities encountered were neutropenia (12.5%), anemia (0%), thrombocytopenia (0%). Non-hematological 3/4 toxicities were not observed. Conclusion : A combination of gemcitabine and vinorelbine in patients previously treated for non-small cell lung cancer provides a relatively good response rate, and a low toxicity profile. However, further study will be needed to confirm its effectiveness.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.6
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• pp.655-662
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• 2011

For analyzing seismic performance of long-span bridge for multi-support excitation and preparing technically and efficiently for a variety of design demands, the new module on multiple excitation was built in a reliable non-linear analysis program(RCAHEST) by using Influence Line Method, and the study on structures was performed previously. Also, the result of the analysis through RCAHEST was compared and verified with commercial finite element analysis program SAP2000 by using the feature of Multi-Support Excitation. From these results, nonlinear time history analysis considering multi-support excitation was studied after designing FE model of Incheon cable-stayed bridge. It was proved that the maximum response of horizontal displacement decreased as the time delay was increasing at all nodes of bridge. And then the serviceability of analysis model was evaluated by performing ultimate analysis under changes in maximum acceleration of seismic load data.

• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.563-573
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• 2000

Periodic outbreaks of Newcastle disease (ND) caused by velogenic viscerotropic ND virus (vvNDV) has become a major concern in Korea nowadays. Throughout last epidemic, the winter season in 2000, most chicken flocks infected early, under 2-4 weeks of age, showed high mortality up to 50-100%. Serum samples collected from 201 breeder, 284 layer and 112 broiler chicken flocks were examined to evaluate the efficacy of various vaccination methods and programs routinely used for mass vaccination in the field poultry farms. Despite repeated live vaccination, most poultry flocks vaccinated by drinking water route using nipple water supply system failed to produce solid active immune response to NDV during the growing time. In the present study, we applied the spray vaccination technique using Ulvavac or Desvac sprayer to the experimental poultry flocks and examined the efficacy of live vaccination effects induced by it under field condition. Measurable antibody to NDV as well as early protection against vvNDV challenge were found in poultry flocks vaccinated by spray route. Further, we did not found significant post vaccination reactions caused by spray vaccination if properly administered. These data indicate that the spray vaccination will be safe and reliable mass vaccination method for the prevention of ND.

• The Korean Journal of Emergency Medical Services
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• v.17 no.3
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• pp.115-137
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• 2013

Purpose: The purpose of this study was to investigate the extended job of paramedic after the 1st job description in 2000 by the National Health Personnel Licensing Examination Board. Methods: This study was carried out from May 2012 to July 2013 on the Developing A Curriculum (DACUM) method to analysts 330 responses among 400 questionnaires (response rate 82.5%) after analysing 30 pilot questionnaires. In order to enhance validity and reliability of this job description, 2 job analysts in universities and 10 EMT-Paramedics in hospitals and fire stations were recruited. Results: There were differences between 166 (year 2000) and 240 (2012) in task element. There were higher answering at triaging patient(2.64 frequency, 4.15 importance), calling for help(2.68 frequency, 4.07 importance) in disaster emergency care. There were higher answering at measuring vital sign (3.95 frequency, 4.22 importance), measuring ECG(3.84 frequency, 4.14 importance), wound care(3.48 frequency, 3.86 importance), bleeding control & wound care(3.46 frequency, 3.86 importance), applying $O_2$(3.40 frequency, 3.94 importance) in physician assistant. Conclusion: Scope of extended practice as a physician assistant in hospital setting recommended us to replace the present curriculum and national exam with new curriculum and national written & skill test.