• Journal of Korean Association for Spatial Structures
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• v.16 no.3
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• pp.89-97
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• 2016

With the recent trend to construct high-rise and large buildings, the steel structure system is widely used, but there are not enough studies on the vibration characteristics of the iFLASH system on the buildings. Therefore, in this study, we performed a vibration measurement of the natural frequency and damping ratio in the stage of iFLASH panel, composit, frame completion and cladding completion. The result findings suggest that the damping ratio after the cladding completion has a greater effect on the reduction of the damping ratio, than the stage after the frame completion.

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.337-340
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• 2004

Upper stage telemetry system of KSLV- I (Korea Space Launch Vehicle I) is composed of MDU (Master Data Unit), RDU (Remote Data Unit), SRU (Shock Recorder Unit) and Transmitter. RDU is the front-end telemetry data acquisition unit which gathers analog/discrete signals from various sensors and other units, and transmits the processed data to MDU via MIL-STD-I553B data bus. In order to acquire useful data from analog signal, signal conditioning circuits, such as anti-aliasing or amplifying, should be implemented. For this purpose, SCM (Signal Conditioning Module) had been developed. This paper describes hardware structure of SCM and analog signal conditioning circuits for various sensors. Also, sampling time scheme for different sampling rates were designed and tested.

• Aerospace Engineering and Technology
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• v.10 no.2
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• pp.128-132
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• 2011

We can acquire the criteria of configuration tolerance on the Kick Motor system, KSLV-I upper stage propulsion system from the analysis results of the initial controllability on the KSLV-I upper stage. Also we can assign configuration tolerances on each subsystem from the configuration tolerance on the Kick Motor system. This article deals with the Kick Motor system configuration tolerance criteria and the results of configuration management on the both ground test models and flight test ones.

• Journal of Gastric Cancer
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• v.4 no.4
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• pp.225-229
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• 2004

Purpose: Some patients develop gastroesophageal reflux disease (GERD) after a gastrectomy for stomach cancer. Therefore, we conducted this research to gain an understanding of esophageal acidity and motility change. Materials and Methods: From July 2002 to March 2004, the cases of 15 randomized patients with stomach cancer who underwent a radical subtotal gastrectomy (RSG) with Billroth I(B-I) reconstruction (n=12) or a radical total gastrectomy (RTG) with Roux-en-Y (R-Y) gastroenterostomy (n=3) were analyzed. We investigated the clinical values of the ambulatory 24-hour pH monitoring and esophageal manometry in these patients, just before discharge from the hospital after an operation. Results: GERD was present in three patients ($20\%$). Compared with two reconstructive procedures, 3 of the 12 patients in the RSG with B-I group had GERD; however, none of RTG with R-Y group had GERD. Compared with pathologic stage, 2 of 9 patients in stage I, 1 of 2 patients in stage II, none of 3 patients in stage III, and none of 1 patient in stage IV had GERD. Esophageal manometry was performed in 10 patients. Nonspecific esophageal motility disorder (NEMD) was present in 7 patients. Conclusion: Some patients had GERD as a complication following a gastrectomy for stomach cancer. We suspect that the postoperative esophageal symptom is due to not only bile reflux but also gastroesophageal acid reflux. Therefore, careful observation is recommended for the detection of GERD.

• Economic and Environmental Geology
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• v.41 no.1
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• pp.1-14
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• 2008

The Bongsang gold-silver deposit consists of quartz veins that fill along the fault Bone within Cretaceous andesitic lapilli tuff. Mineralization is occurred within fault-breccia zones and can be divided into two stages. Stage I which can be subdivided into early and late depositional stages is main ore mineralization and stage II is barren. Stage I began with deposition of wall-rock alteration minerals and base-metal sulfides, and was deposited by later native silver, Ag-bearing tetrahedrite, polybasite and base-metal sulfides such like pyrite, sphalerite, chalcopyrite and galena. Fluid inclusion data indicate that homogenization temperatures and salinities of stage I range from 137 to $336^{\circ}C$ and from 0.0 to 10.6 wt.% NaCl, respectively. It suggests that ore forming fluids were cooled and diluted with the mixing of meteoric water. Also, temperature and sulfur fugacity deduced mineral assemblages of late stage I are $<210^{\circ}C\;and\;<10^{-15.4}$ atm, respectively. Sulfur(3.4%o) isotope composition indicates that ore sulfur was mainly derived from a magmatic source as well as the host rocks. The calculated oxygen{2.9%o, 10.3%o(quartz: 7.9%o, 8.9%o, calcite: 2.9%o, 10.3%o)}, hydrogen(-75%o) and carbon(-7.0%o, -5.9%o) isotope compositions indicate that hydrothermal fluids may be meteoric origin with some degree of mixing of another meteoric water for paragenetic time.

• Clinical and Experimental Reproductive Medicine
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• v.33 no.4
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• pp.219-227
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• 2006

Objective: To evaluate the impact of endometriosis on IVF-ET cycles and to compare IVF outcomes between stage I/II and stage III/IV endometriosis. Methods: We analyzed 697 patients (1,199 cycles) with endometriosis (stage I-II:638 cycles, stage III-IV: 561 cycles) and 325 pts (459 cycles) with tubal factor as controls between January 1994 and April 2004. Pts with endometriosis were diagnosed by laparoscopy and medical and surgical treatment were done in 353 cycles (55.3%) and 466 cycles (83.1%) of stage I-ll/stage III-IV endometriosis. Cycles with age>35 years or FSH>20 miU/mL or severe male factor infertility were excluded. Results: The number of retrieved oocytes ($9.97{\pm}7.2$ vs. $13.4{\pm}7.9$ (p<0.0001 )), total number of embryos ($6.5{\pm}4.8$ vs. $9.1{\pm}5.6$ (p<0.0001)), and good quality embryos ($2.43{\pm}1.6$ vs. $2.74{\pm}1.7$ (p=0.013)) significantly decreased in stage III-IV endometriosis than in control. But pregnancy rate of stage III-IV endometriosis was comparable with control (35.7% vs. 36.8%). Fertilization rate and number of total embryos were lower in stage I-II endometriosis than in control ($64.8{\pm}22.9$ vs. $70.8{\pm}20.8$ (p<0.0001), $7.6{\pm}5.0$ vs. $9.1{\pm}5.6$ (p<0.0001)). In patients with medical and surgical treatment of endometriosis, pregnancy rate and live birth rate was significantly lower in stage I-II than in stage III-IV endometriosis (29.2 vs. 36.2 (%), p=0.045, 23.9 vs. 31.5 (%), p=0.043). There was no difference in the mean age, but the duration of infertility was significantly longer ($56.5{\pm}26.3$ vs. $46.9{\pm}25.8$ (mon), p<0.0001) and fertilization rate was lower ($64.7{\pm}23.3$ vs. $70.5{\pm}22.7$ (%), p=0.001) in stage I-II than stage III-IV endometriosis. Conclusion: We suggest that IVF should be considered earlier in patients with minimal to mild endometriosis because of significantly decreased fertilization rates.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.679-680
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• 2013

• Tuberculosis and Respiratory Diseases
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• v.68 no.1
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• pp.10-15
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• 2010

Background: Lung cancer is the most common cause of cancer mortality in Korea. The TNM stage at presentation in patients with non-small cell lung cancer (NSCLC) has the greatest impact on prognosis. Patients who undergo a complete resection for NSCLC are likely to develop recurrent and/or metastatic disease. There are several factors influencing the development of recurrence. We explored risk factors of recurrence in patients with stages I and II NSCLC, who had undergone curative resection. Methods: We reviewed patients who had complete surgical resection as definitive treatment for stage I or II. Patients followed up for more than 36 months. We evaluated several factors which might have relationship with recurrence, such as patient's demographic factors, TNM staging, pathologic finding, tumor markers and surgical technique. Results: A total of 75 patients were enrolled for analysis, of whom 58 were men and 17 were women with mean age of 61 (range, 37 to 76) years. The average size of tumors was 3.9 cm (0.7 to 10 cm). There were 64 patients with stage I NSCLC and 11 with stage II NSCLC. Among 64 patients with stage I NSCLC, 35 patients showed recurrences whereas 8 patients have recurred in stage II NSCLC. Grade of differentiation of tumor was closely related to the recurrence. Seventy-five percent of patients who had poor tumor differentiation experienced a recurrence. In contrast, 3 patients of twelve had recurrences, who revealed differentiation in their tissue (p<0.05). Conclusion: Tumor differentiation could be a predictive factor for tumor recurrence in patients who have undergone curative resection for stage I or II NSCLC.

• Economic and Environmental Geology
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• v.54 no.6
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• pp.753-765
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• 2021

The Dongwon Au-Ag deposit is located within the Paleozoic Taebaeksan province, Okcheon belt. Mineral paragenesis can be divided into two stages (stage I, ore-bearing quartz veins; stage II, barren carbonate veins) by major tectonic fracturing. Stage I, at which the precipitation of major ore minerals occurred, is further divided into three substages(early, middle and late) with paragenetic time based on minor fractures and discernible mineral assemblages: early, marked by deposition of pyrite with minor magnetite, pyrrhotite and arsenopyrite; middle, characterized by introduction of electrum and base-metal sulfides with minor sulfosalts; late, marked by argentite, Cu-As (and/or Sb) and Ag-Sb sulfosalts with base-metal sulfides. Fluid inclusion data show that stage I ore mineralization was deposited between initial high temperatures (≥430℃) and later lower temperatures (≤230℃) from fluids with salinities between 6.0 to 0.4 wt. percent equiv. NaCl. The relationship of salinity and homogenization temperature suggest that ore mineralization at Dongwon was deposited mainly due to fluid boiling, cooling and dilution via influx of cooler, more dilute meteoric waters. Changes in stage I vein mineralogy reflect decreasing temperature and fugacity of sulfur by evolution of the Dongwon hydrothermal system with increasing paragenetic time. The Dongwon deposit may represents a Korean-type and/or Au-Ag type mesothermal/epithermal gold-silver deposit.

• Economic and Environmental Geology
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• v.55 no.6
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• pp.689-699
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• 2022

The Ssangjeon tungsten deposit is located within the Yeongnam Massif. Within the area a number of hydrothermal quartz veins were formed by narrow open-space filling of parallel and subparallel fractures in the metasedimentary rocks as Wonnam formation, Buncheon granite gneiss, amphibolite and/or pegmatite. Mineral paragenesis can be divided into two stages (stage I, ore-bearing quartz vein; stage II, barren quartz vein) by major tectonic fracturing. Stage I, at which the precipitation of major ore minerals occurred, is further divided into three substages (early, middle and late) with paragenetic time based on minor fractures and discernible mineral assemblages: early, marked by deposition of arsenopyrite with pyrite; middle, characterized by introduction of wolframite and scheelite with Ti-Fe-bearing oxides and base-metal sulfides; late, marked by Bi-sulfides. Fluid inclusion data show that stage I ore mineralization was deposited between initial high temperatures (≥370℃) and later lower temperatures (≈170℃) from H₂O-CO₂-NaCl fluids with salinities between 18.5 to 0.2 equiv. wt. % NaCl of Ssangjeon hydrothermal system. The relationship between salinity and homogenization temperature indicates a complex history of boiling, fluid unmixing (CO₂ effervescence), cooling and dilution via influx of cooler, more dilute meteoric waters over the temperature range ≥370℃ to ≈170℃. Changes in stage I vein mineralogy reflect decreasing temperature and fugacity of sulfur by evolution of the Ssangjeon hydrothermal system with increasing paragenetic time.