• Journal of Korean Association for Spatial Structures
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• v.10 no.2
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• pp.105-115
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• 2010

Recently, High-rise building are irregular-shaped to be city landmarks and function as vertical cities to enable the efficient use of land. 3T (Twisted, Tilted & Tapered) designs are being suggested for irregular buildings and studies to develop new structural system have been actively made to satisfy slender shape ratio. In diagrid system, not only gravity load but also lateral load is delivered based on the triangular shape of diagrid, so most of columns are eliminated. Because shearing force is delivered by the axial behavior (tensile/compressive) of diagrid to minimize shearing deformation, the system is more applicable to irregular buildings than existing system where shearing force is delivered by the columns. In this study, the process of selecting connection details and the structural safety of the selected details are verified using the finite element analysis with focus given to the construction overview of the Cyclone Tower. However, the relersed methods of stress concentration are suggested and the performance of stress concentration relieves that it's suggested for the appropriate cap plate thickness and extended length.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.40.3-41
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• 2017

Korea Astronomy and Space Science Institute The observation of particles and waves using a single satellite inherently suffers from space-time ambiguity. Recently, such ambiguity has often been resolved by multi-satellite observations; however, the inter-satellite distances were generally larger than 100 km. Hence, the ambiguity could be resolved only for large-scale (> 100 km) structures while numerous microscale phenomena have been observed at low altitude satellite orbits. In order to resolve those spatial and temporal variations of the microscale plasma structures on the topside ionosphere, SNIPE mission consisted of four (TBD) nanosatellites (~10 kg) will be launched into a polar orbit at an altitude of 700 km (TBD). Two pairs of satellites will be deployed on orbit and the distances between each satellite will be from 10 to 100 km controlled by a formation flying algorithm. The SNIPE mission is equipped with scientific payloads which can measure the following geophysical parameters: density/temperature of cold ionospheric electrons, energetic (~100 keV) electron flux, and magnetic field vectors. All the payloads will have high temporal resolution (~ 16 Hz (TBD)). This mission is planned to launch in 2020. The SNIPE mission aims to elucidate microscale (100 m-10 km) structures in the topside ionosphere (below altitude of 1,000 km), especially the fine-scale morphology of high-energy electron precipitation, cold plasma density/temperature, field-aligned currents, and electromagnetic waves. Hence, the mission will observe microscale structures of the following phenomena in geospace: high-latitude irregularities, such as polar-cap patches; field-aligned currents in the auroral oval; electro-magnetic ion cyclotron (EMIC) waves; hundreds keV electrons' precipitations, such as electron microbursts; subauroral plasma density troughs; and low-latitude plasma irregularities, such as ionospheric blobs and bubbles. We have developed a 6U nanosatellite bus system as the basic platform for the SNIPE mission. Three basic plasma instruments shall be installed on all of each spacecraft, Particle Detector (PD), Langmuir Probe (LP), and Scientific MAGnetometer (SMAG). In addition we now discuss with NASA and JAXA to collaborate with the other payload opportunities into SNIPE mission.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.4
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• pp.11-15
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• 2001

In this paper, hermetic sealing technology was studied for wafer level packaging of the RF-MEMS devices. With the flip-chip bonding method. this non-conductive B-stage epoxy sealing will be profit to the MEMS device sealing. It will be particularly profit to the RF-MEMS device sealing. B-stage epoxy can be cured by 2-step and hermetic sealing can be obtained. After defining 500 $\mu\textrm{m}$-width seal-lines on the glass cap substrate by screen printing, it was pre-baked at $90^{\circ}C$ for about 30 minutes. It was, then, aligned and bonded with device substrate followed by post-baked at $175^{\circ}C$ for about 30 minutes. By using this 2-step baking characteristic, the width and the height of the seal-line could be maintained during the sealing process. The height of the seal-line was controlled within $\pm$0.6 $\mu\textrm{m}$ in the 4 inches wafer and the bonding strength was measured to about 20MPa by pull test. The leak rate, that is sealing characteristic of the B-stage epoxy, was about $10^{-7}$ cc/sec from the leak test.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.2
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• pp.1-5
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• 2003

In this project, the efficiency of localized heating for micro systems packaging is developed by using a forced potential scheme microheater. Less than 0.2 Mpa contact pressure was used for bonding with a 200 mA current input for $50{\mu}m$ width, $2{\mu}m$ height and $8mm{\times}8mm$, $5mm{\times}5mm$, $3mm{\times}3mm$ sized phosphorus-doped poly-silicon microheater. The temperature can be raised at the bonding region to $800^{\circ}C$, and it was enough to achieve a strong and reliable bonding in 3 minutes. The IR camera test results show improved uniformity in heat distribution compared with conventional microheaters. For performing the gross leak check, IPA (Isopropanol Alcohol) was used. Since IPA has better wetability than water, it can easily penetrate small openings, and is more suitable for conducting a gross leak check. The pass ratio of bonded dies was 67%, for conventional localized heating, and 85% for our newly developed FP scheme. The bonding strength was more than 25Mpa for FP scheme packaging, which shows that FP scheme can be a good candidate for micro-scale hermetic packaging.

• The Korean Journal of Ecology
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• v.24 no.3
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• pp.141-147
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• 2001

Soil respiration and some environmental factors which affect soil respiration were studied in an oak forest, Kongju, Korea. Soil respiration was measured at midday of the 15th and 30th day at every month in control(Con), artificial forest gap (Gap) and litter removed area (Lr) with portable CO₂ Analyzer equipped soil respiration chamber. In July, maximum soil respiration in Con, Cap and Lr was 15.6, 11.2 and 7.7 CO₂μmol·m/sup -2/·s/sup -1/, respectively. Respiration in Gap and Lr decreased by 28.6% and 50.6%, respectively, compared with that in Con. Annual amount of soil CO₂ evolution from Con, Gap and Lr was 6.86, 5.84, 3.81 kg·m/sup -2/·yr/sup -1/, respectively. Annual amount of CO₂ evolution in Gap and Lr decreased by 14.8% and 44.5%, respectively, compared with that in Con. Soil respiration rates exponentially increased with temperature. Temperature of soil surface and at 5 cm depth was strongly related to soil respiration rates in Con (r₂＝0.87, 0.93), Gap (r₂=0.81, 0.88) and Lr (r/sub 2/=0.89).

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5681-5686
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• 2015

Background: Pancreatic cancer ranks fourth in deaths caused by cancers throughout the world. Gemcitabine chemotherapy is the primary method of treatment of advanced pancreatic cancer, and in asco2014, it is still firstline chemotherapy. Howeve,r gemcitabine+fluorouracil regimens are also licensed and widely used worldwide. Clinical trials are the best way to evaluate drug efficacy. In this study, we performed a systematic review and a meta-analysis of randomized controlled trials (RCTs) to assess whether gemcitabine+fluoropyrimidine combination therapy improves the prognosis of unresectable pancreatic cancer compared with gemcitabine treatment alone. Materials and Methods: A quantitative up-to-date meta-analysis was undertaken to investigate the efficacy of gemcitabine-based combination treatment compared with gemcitabine monotherapy for locally advanced or metastatic pancreatic cancer. Inclusion was limited to high-quality randomized clinical trials. Results: A total of 12 studies were included in the present analysis, with a total of 3,038 patients recruited. The studies were divided into three subgroups including 5-FU / CAP / S-1 combined with gemcitabine. For the primary endpoint of overall survival (OS), gemcitabine-based combination therapy demonstrated significantly better outcome (HR, 0.88; 95% CI, 0.81-0.95) than gemcitabine monotherapy. The analysis of progression free survival (PFS) also provided a significant result for the combined therapy in a total of 8 trials (2,130 patients) (HR, 0.74; 95% CI, 0.63-0.86). With subgroup analysis according to the method of dosing delivery, we found that in the injection group with 3 trials (889 patients), a negative result was found (HR, 0.93; 95% CI, 0.77-1.12); while a positive result was observed in the oral group with 9 trials (2,149 patients) (HR, 0.87; 95% CI, 0.80-0.95). Conclusions: Gemcitabine combination therapy provides a modest improvement of survival, but is associated with more toxicity compared with gemcitabine monotherapy.

• Journal of Mushroom
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• v.15 no.1
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• pp.14-20
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• 2017

The oyster mushroom cultivation house typically has multiple layers of growing shelves that cause the disturbance of air circulation inside the mushroom house. Due to this instability in the internal environment, growth distinction occurs according to the area of the growing shelves. It is known that minimal air circulation around the mushroom cap facilitates the metabolism of mushrooms and improves their quality. For the purpose of this study, a CFD analysis FLUENT R16 has been carried out to improve the internal environment uniformity of the oyster mushroom cultivation house. It is found that installing a section of the working passage towards the ceiling is to maintain the internal environment uniformity of the oyster mushroom cultivation house. When all the environment control equipment - including a unit cooler, an inlet fan, an outlet fan, an air circulation fan, and a humidifier - were operated simultaneously, the reported Root Mean Square (RMS) valuation the growing shelves were as follows: velocity 23.86%, temperature 6.08%, and humidity 2.72%. However, when only a unit cooler and an air circulation fan operated, improved RMS values on the growing shelves were reported as follows: velocity 23.54%, temperature 0.51%, and humidity 0.41%. Therefore, in order to maintain the internal environment uniformity of the mushroom cultivation house, it is essential to reduce the overall operating time of the inlet fan, outlet fan, and humidifier, while simultaneously appropriately manage the internal environment by using a unit cooler and an air circulation fan.

• Journal of Mushroom
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• v.16 no.3
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• pp.186-191
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• 2018

In order to breed a new Pleurotus eryngii cultivar with a large pileus and convex shape, which are favorite traits of customers from Europe and North America, single crosses between monokaryotic mycelia derived from basidiospores of KNR2555 were performed to yield the new cultivar $2{\times}12$ chosen by cap shape (convex), diameter of pileus (60.7 mm), and quality (4.9) in a preliminary cultivation. The strain was named Gat_aeryni and was cultivated on a large scale for comparison with Kenneutari 2 ho at the GNARES and at mushroom farms. The yield of Gat_aeryni (71.7 g) was not significantly different from that of Kenneutari 2 ho (71.4 g), and the quality of the new cultivar was 6.8, which was not significantly different from that of a reference cultivar (6.5). Days for harvest, length, and diameter of the pileus in the two cultivars were statistically different by an independent t-test (P < 0.001, P < 0.05, P < 0.001 and P < 0.05 respectively). The new and reference cultivars were discriminated by PCR reactions with a primer set (URP1 and URP10) and simultaneous cultivation.

• The Journal of the Korea Contents Association
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• v.5 no.5
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• pp.124-132
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• 2005

While use of a pet bottle with use it is light recently and convenient increases quickly, it is used from the child, also diffusing the user to a pet bottle to people of various classes, such as an old person, a woman, a male, the man in the street, and a disabled person. However, those who are standardized on the basis of the common man with the plan energy of a pet bottle, and cannot attain to the standard, That is, a child and a disabled person may be condemnedto the vague situation that a lid cannot be opened or a contents thing cannot be drunk without external help. And the characteristic of a material and production which are called PET Even if convenience is emphasized for the cost reduction of COST, a design is chosen easily, and even if it calls it the man in the street, the point of coming to experience a situation with the difficult time of use can be found well. In research of a book, problem derivation which classifies entering school and a preschool boy and girl child for a child drink for an object first by the viewpoint of universal design paying attention to such problems, and leads the actual use example of a pet bottle was carried out in true heart, and various notional approach was shown by the solution method.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.4
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• pp.347-359
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• 2009

The concentrations of PAHs in $PM_{10}$ fine particles were determined at two sites, which were Jongno, one of the urban core sites of Seoul, and Yongin, a downwind site of Seoul. The average concentration of PAHs in $PM_{10}$ was $19.92{\pm}18.49\;ng\;m^{-3}$ with the range of $1.28{\sim}81.22\;ng\;m^{-3}$ at Jongno site of Seoul from August 2006 to August 2007, and $14.06{\pm}9.96\;ng\;m^{-3}$ with the range of $1.66{\sim}31.84\;ng\;m^{-3}$ at Yongin site from September to November of 2006. In the results of monthly comparison, the concentration of PAHs in August was the lowest level of $3.23\;ng\;m^{-3}$, but the highest level of $46.24\;ng\;m^{-3}$ in January. The seasonal comparison showed the concentration in winter was higher by the factor of 11.9 than in summer. The concentrations of PAHs during a warm period (November${\sim}$March) increased as 5.1 times higher than those during a cold period (April${\sim}$October). The concentrations of PAHs were assumed to be largely attributed to the consumption of fossil fuels, temperature, mixing height, and photochemical reactions in Seoul metropolitan area.