• 한국산학기술학회논문지
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• 제8권4호
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• pp.815-820
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• 2007

본 논문에서는 휴대용 무선통신기기에 장착해서 사용 가능한 소형 내장형 이중대역(RFID, PCS) 안테나가 소개되었다. 제안된 안테나는 기본적인 PIFA(Planar Inverted-F Antenna) 구조이며 기존 안테나 방사체 아래쪽에 변형된 접지구조를 추가하였다. 이 변형된 접지 구조는 안테나에 의해 유기되는 전류를 분산시키고 안테나 주 방사부와 결합성분을 유도하여 안테나를 소형화시킨다. 시뮬레이션 결과에 따라 안테나가 실제 제작되고 측정되었으며 변형된 접지로 인해 공진 주파수가 낮은 주파수 대역으로 150MHz 정도 이동하는 것을 볼 수 있었다. 그리고 제안된 안테나의 표면전류가 분산되는 특징이 관찰되어 전자파흡수율(SAR)과 보청기호환성(HAC)을 개선하는데 사용될 수 있다.

• 한국습지학회지
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• 제14권4호
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• pp.439-455
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• 2012

파랑 수치모형인 SWAN 수치모형, 파랑에 의해 발생되는 기인력 수치모형인 WIF 수치모형, 그리고 흐름장 수치모형은 EFDC 수치모형을 연동하여 최종적으로 파랑류 계산이 가능한 WIC 수치모형을 개발하였다. 개발된 WIC 수치모형을 검증하기 위하여 Goda(2000)가 적용한 수중 원형천퇴의 파랑변형 계산하여 파고, 파랑의 굴절과 회절을 비교하였으며, 파고비 결과는 약 1~5 %의 차이를 보였다. 파랑에 의한 기인력 수치모형은 기존의 Longuet-Higgins and Stewart(1960)가 제안한 잉여응력에 의해 발생하는 기인력에 Dally and Osiecki(1994)가 제안한 roller로 인한 응력에 의해 발생되는 기인력을 추가하였고, Kim(2004)이 제안한 완화기법을 도입하여 lateral mixing 처리를 수행하지 않아도 자연현상과 유사한 결과를 얻을 수 있도록 개발되었다. 개발된 파랑에 의한 기인력 수치모형은 계산시 ${\Delta}t$에 제약을 받지 않는다는 장점을 가지고 있으며, 흐름장 수치모형의 source항이 되어 파랑류의 양상을 계산할 수 있도록 하였다. 연계된 파랑류 수치모형을 검증하기 위해서 Nishimura et al.(1985)의 수리모형실험과 Kim(2004)의 수심적분된 파랑류 수치모형과 비교하였다. 이안제 배후에서 연안류의 유속분포와 이안류의 유속분포 결과가 기존의 수리모형실험과 수치모형실험의 결과와 상당히 일치함이 관측되었다.

• 대한원격탐사학회지
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• 제27권3호
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• pp.235-258
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• 2011

The purpose of this study is to investigate climatological variations from the temporal and spatial surface particulate organic carbon (POC) estimates based on SeaWiFS spectral radiance, and to determine the physical mechanisms that affect the distribution of pac in the Gulf of Mexico. 7-year monthly mean values of surface pac concentration (Sept. 1997 - Dec. 2004) were estimated from Maximum Normalized Difference Carbon Index (MNDCI) algorithm using SeaWiFS data. Synchronous 7-year monthly mean values of remote sensing data (sea surface temperature (SST), sea surface wind (SSW), sea surface height anomaly (SSHA), precipitation rate (PR)) and recorded river discharge data were used to determine physical forcing factors. The spatial pattern of POC was related to one or more factors such as river runoff, wind-derived current, and stratification of the water column, the energetic Loop Current/Eddies, and buoyancy forcing. The observed seasonal change in the POC plume's response to wind speed in the western delta region resulted from seasonal changes in the upper ocean stratification. During late spring and summer, the low-density river water is heated rapidly at the surface by incoming solar radiation. This lowers the density of the fresh-water plume and increases the near-surface stratification of the water column. In the absence of significant wind forcing, the plume undergoes buoyant spreading and the sediment is maintained at the surface by the shallow pycnocline. However, when the wind speed increases substantially, wind-wave action increases vertical motion, reducing stratification, and the sediment were mixed downward rather than spreading laterally. Maximum particle concentrations over the outer shelf and the upper slope during lower runoff seasons were related to the Loop Current/eddies and buoyancy forcing. Inter-annual differences of POC concentration were related to ENSO cycles. During the El Nino events (1997-1998 and 2002-2004), the higher pac concentrations existed and were related to high runoffs in the eastern Gulf of Mexico, but the opposite conditions in the western Gulf of Mexico. During La Nina conditions (1999-2001), low Poe concentration was related to normal or low river discharge, and low PM/nutrient waters in the eastern Gulf of Mexico, but the opposite conditions in the western Gulf of Mexico.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.331-335
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• 2004

This study is focused to analyze the movement of thermal effluent dischargeed from nuclear power plant by season, ebb and flow, and before and after foundation of tide embankment using thermal infrared band image of 28 scenes observed from Landsat from 1987 to 2004, which is the early stage of operation of young-kwang nuclear power plant. In diffusion of thermal effluent discharge by seasons, spring and summer is spreading further than autumn and winter. It is considered to distribute widely mixed with thermal effluent discharge and hot water, which is distributed naturally along the seaside. It is known the fact that tidal currents control the direction of diffusion of thermal effluent discharge by the change of ebb and flow. Namely, it is distributed widely on the Southwest direction along the seaside by tidal currents when ebb and, it is moved widely on the Northeast direction along the seaside by tidal current when flood. However, in the early stage of flood current, the mainstream of thermal effluent discharge is spread on Southwest direction and, the direction is changed on North­east way when the latter period of flood current. Similarly, in the early stage of ebb current, the mainstream of thermal effluent discharge is spread on Northeast direction and, the direction is changed on Southwest direction when the latter period of ebb current. As the result of comparing to the diffusion pattern of thermal effluent discharge before and after the foundation of seawall, discharged thermal effluent from the drain of plant by the foundation of dike is shown as curved circle pattern on Northeast to West direction from the ending portion of the seawall.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1971-1973
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• 1999

Monolayers of azo-benzene group containing fatty acids(8A5H) were made by spreading and compressing on the water surface. These monolayers were optically stimulated by illuminating the lights of 365[nm] and 450[nm] from X-non lamp, and the structural changes of the molecules were measured by the displacement current method. Also, the dynamic behaviors of these monolayers were measured by the $\pi-A$ isotherms when changing the temperatures of the water surface. As results, when the monolayers were stimulated by 365[nm] light, the positive currents which were generated by the structural changes from trans to cis were measured. But the negative currents of the structural changes from cis to trans were too weak to detect. When the temperatures of the water surface were increased, surface pressures of the monolayers increased early because of the thermal activations of the molecules, and the double liquid film phase were disappeared upon $40[^{\circ}C]$.

• Journal of Microbiology and Biotechnology
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• 제30권8호
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• pp.1109-1115
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• 2020

The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spreading globally, and the WHO has declared this outbreak a pandemic. Vaccines are an effective way to prevent the rapid spread of COVID-19. Furthermore, the immune response against SARS-CoV-2 infection needs to be understood for the development of an efficient and safe vaccine. Here, we review the current understanding of vaccine targets and the status of vaccine development for COVID-19. We also describe host immune responses to highly pathogenic human coronaviruses in terms of innate and adaptive immunities.

• Asian Pacific Journal of Cancer Prevention
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• 제15권1호
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• pp.133-137
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• 2014

Background: Today, breast cancer is increasing in nearly all societies. Currently, cancers are the third leading cause of death in Iran after cardiovascular diseases and accidents. Of the cancers, breast cancer is spreading particularly rapidly among Iranian women. Negative effects of discontinuation of care on patient survival have been well documented. Inhibiting or facilitating factors affecting continuity of care at different stages of the patient care continuum should be identified. Materials and Methods: The current study implemented a qualitative method that provided tools to examine factors in detail. This study was conducted on 22 women, undergoing surgery and chemotherapy after being diagnosed with breast cancer. Content analysis was the technique adopted. Results: The effective factors in continuity of care from the patients' perception, based on the participant statements, were classified into three categories of evaluation of symptoms, psychological reactions, and care triggers with several subcategories. Conclusions: According to the outcomes of the current study, it can be noted that, the patient experiences can be brought into use by health-care professionals and assist them in providing patient sand their families with adequate consulting services. It can also provide an opportunity for making interventions tailored to the community culture, and closer adherence of patients to the prescribed treatments.

• E2M - 전기 전자와 첨단 소재
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• 제11권10호
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• pp.60-65
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• 1998

Deposition conditions, surface morphology, and electrical properties of polyamic acid alkylamine salts (PAAS) Langmuir-Blodgett(LB) films have been investigated through a study of surface pressure-area $\pi$-A isotherms, AFM (atomic force microscopy), and current-voltage characteristics. To obtain the optimum conditions of film deposition, the $\pi$-A isotherms were examined by varying temperature, barrier moving speed, dipping speed, spreading amount of solution etc. The Z-type LB films were made at the surface pressure of 5 mN m-1 and 25 mN m-1 for the AFM study; the former surface pressure forms the gas phase and the latter one forms the solid phase. The LB film made in the gas phase show domains with a size of about 200 A diameter and 70 A height. However, the LB films made in the solid phase show a very smooth surface with 2 A surface roughness. In the current-voltage characteristics measured along the perpendicular direction of the films, ohmic conduction has been observed below 105 V cm-1 and the calculated electrical conductivity is about 10-13 S cm-1. Nonohmic conduction has been observed above = 10-11 V cm and the conduction mechanism can be explained by the Schottky effect.

• 한국표면공학회지
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• 제43권1호
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• pp.1-6
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• 2010

The effect of organic additives, 1-(3-sulfoproyl)-2-vinylpyridineium hydroxide (SVH) and thiourea (TU), on the precision copper electrodeposition was investigated with optical, electrochemical and x-ray diffraction techniques. It was found that SVH played a r ole as a n accelerator and TU as an i nhibitor during the electroreduction of cupric ions in acidic Cu electroplating solution. Through electrochemical measurements, TU showed more strong interaction with cupric ions than SVH and dominated overall Cu electroplating process when both additives were present in the solution. In the case of three dimensional Cu electrodeposition on the 20 ${\mu}m$-patterned Ni substrates, SVH controlled the upright growth of Cu electrodeposits and so determined its flatness, while TU prohibited the lateral spreading of Cu in the course of pulse-reverse pulse current adaptation. With microscopic observation, we obtained the optimum organic additives composition, that is, 100 ppm SVH and 200 ppm TU during the current pulsation.

• 융합보안논문지
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• 제11권3호
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• pp.75-84
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• 2011

모바일 기술의 급격한 발전으로 스마트폰 사용이 확산되고 있다. 미래의 모바일 뱅킹 시장 활성화를 위해서 무엇보다 중요하고 우선시되는 것은 안전한 금융 거래이다. 그러나, 스마트폰 확산에 비례하여 검증되지 않은 많은 앱들이 개발되고 있는 상황에서 보안 위협은 높아질 수 밖에 없다. 현재 스마트폰 금융 거래 방식은 기존 공인인증서나 OTP기술을 그대로 모바일 환경에 적용하고 있으나, 많은 보안 문제점이 꾸준히 지적되고 있다. 본 논문은 다단계 인증 방법을 통해 보안성을 강화하고 물리적 부인방지 기능을 제공함으로써 기존의 인증 방식의 보안성을 개선하고자 한다.