• 약학회지
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• 제54권3호
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• pp.180-186
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• 2010

Aldosterone, mineralocorticoid hormone, has important functions related to the regulation of blood pressure and balance of fluids and electrolytes in the distal region of the nephron. By genomic and non-genomic action of aldosterone, the physiological kidney functions are modulated. However, many of them except several kind of sodium channel have not been identified and analyzed yet. In this study, proteomic technologies with two-dimensional gel electrophoresis (2-DE) gel using aldosterone rat model were applied to analyze and identify the aldosterone dependently expressed proteins in rat kidney cortex. As a result, the established aldosterone rat model exhibited the normal physiological responses to aldosterone and modulated proteins were identified, which included 15 increased and 3 decreased proteins on 2-DE analysis. Among them, 11 proteins were identified as changed proteins by LC-MS/MS analysis. These proteins identified as aldosterone induced proteins were involved in several cellular pathways such as cytoskeleton remodeling, energy metabolism, amino acid metabolism, and chaperone process. In conclusion, our data could provide the insights into the new mechanism underlying regulation of kidney functions by aldosterone.

• 대한전자공학회논문지TC
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• 제44권7호통권361호
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• pp.70-80
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• 2007

차세대 이동 네트워크에서는 다양한 무선 접속 기술이 공존하게 된다. 이에 따라, 다양한 무선망에서 QoS를 지원하는 분산 방식의 호 수락 제어 구조인 SmartCAC를 제안한다. 본 논문은 네트워크간 정보 수집이 필요없는 분산방식을 위하여 모바일 노드와 네트워크간의 상호동작을 이용한다. SmartCAC는 기본적으로 VHO 호와 새로운 호1의 구분이 가능하도록 함으로써 VHO 호에 핸드오프를 위해 예약된 채널을 사용할 수 있도록 한다. 또한, 효율적인 호 수락 제어를 위하여 QoS 요구와 네트워크 사용에 대한 delay와 reliability를 다룬다. 뿐만 아니라, 이종망에서 네트워크 필터링을 할 수 있도록 모바일노드의 스피드를 이용한다. 이종망의 상태정보를 알 수 없는 모바일노드가 네트워크의 상태정보를 받아 비교할 수 있도록 확장된 프로토콜을 제시하고, 시뮬레이션 연구에서 기존의 CAC 방식과 제어메시지에 의한 비용을 비교하여 37%에서 96%까지 향상되는 효과를 입증한다.

• 정보처리학회논문지A
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• 제16A권4호
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• pp.289-298
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• 2009

일반적인 RFID 시스템은 하나의 리더와 다수의 태그로 구성되며, 단일 무선 공유 채널을 갖는다. 이로 인해 리더의 요구에 여러 태그들이 동시에 응답할 때 빈번하게 충돌이 발생한다. 태그 충돌을 억제하기 위해 QT[8]와 HCT[10], BSCTTA[2], QT-BCS[9]등과 같은 많은 알고리즘들이 제안되어 왔다. 본 논문에서는 BSCTTA 알고리즘을 기반으로 다중 그룹핑과 비트 변화 감지 센서를 이용한 트리 기반 충돌 방지 알고리즘(TABCS, Tree-based anti-collision algorithm using Bit Change Sensing)을 제안한다. 제안된 알고리즘은 비트 변화 감지 장치를 통해 충돌이 발생하더라도 리더는 태그들이 비트 변화 감지 장치를 이용하여 전달한 비트의 유형을 인식할 수 있게 한다. 또한, TABCS는 유일한 프리픽스를 빠르게 생성하게 하고, 모든 태그의 인식에 필요한 비트 전송량을 줄임으로써 기존 알고리즘에 비해 인식 속도를 빠르게 한다. 시뮬레이션을 통한 성능 평가에서 기존에 제안된 다른 알고리즘에 비해 전체적으로 우수한 성능을 보임을 검증한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1672-1677
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• 2004

Leading edge extension(LEX) in a highly swept shape applied to a delta wing features the modem air-fighters. The LEX vortices generated upon the upper surface of the wing at high angle of attack enhance the lift force of the delta wing by way of increased negative suction pressure over the surfaces. The present 3-D stereo PIV includes the Identification of 2-D cross-correlation equation, stereo matching of 2-D velocity vectors of two cameras, accurate calculation of 3-D velocity vectors by homogeneous coordinate system, removal of error vectors by a statistical method followed by a continuity equation criterion and so on. A delta wing model with or without LEX was immersed in a circulating water channel. Two high-resolution, high-speed digital cameras($1280pixel{\times}1024pixel$) were used to allow the time-resolved animation work. The present dynamic stereo PIV represents the complicated vortex behavior, especially, in terms of time-dependent characteristics of the vortices at given measuring sections. Quantities such as three velocity vector components, vorticity and other flow information can be easily visualized via the 3D time-resolved post-processing to make the easy understanding of the LEX effect or vortex emerging and collapse which are important phenomena occurring in the field of delta wing aerodynamics.

• 지능정보연구
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• 제16권1호
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• pp.45-56
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• 2010

센서 네트워크는 이벤트 감지와 통신 기능이 있는 다수의 센서 노드들과 하나 이상의 싱크 노드들로 이루어진 시스템이다. 센서 네트워크는 배치된 지역에 있는 사물의 인식 정보와 주변의 환경 정보를 수집하여 사용자에게 제공한다. 센서 노드의 자원 제약과 무선통신 사용, 기반 시설의 부재로 인해 센서 네트워크는 여러 보안 위협에 취약하다. 센서 네트워크 보안과 관련한 대부분의 기존 연구는 한 가지 공격을 탐지하고 방어하는 것을 목표로 진행되어왔다. 그러나 실제 센서 네트워크에서는 언제 어떠한 공격이 발생할 지 미리 예측할 수 없으며 동시에 여러 가지 공격이 함께 발생할 가능성도 존재한다. 본 논문에서는 센서 네트워크에서 발생 가능한 공격인 허위 보고서 공격과 웜홀 공격을 방어할 수 있는 보안 라우팅 기법을 제안한다. 제안 기법은 기존 보안 기법을 개선 및 결합함으로써 실험 결과 기존 기법보다 높은 공격 검출 성능을 보인다.

• 한국통신학회논문지
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• 제37A권12호
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• pp.1013-1022
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• 2012

RFID 시스템에서 태그 수집은 가장 중요한 기능이다. 태그들은 리더의 수집 명령에 따라서 동일한 채널에서 응답하게 되며, 2개 이상의 태그가 동시에 응답할 때 RFID 시스템에서 태그 충돌이 발생한다. 태그 충돌은 RFID 시스템에서 성능을 저하 시키는 중요한 요소이다. 능동형 RFID 시스템에서는 태그 충돌을 해결하기 위하여 프레임 슬롯 알로하 충돌방지 프로토콜을 널리 사용하고 있다. 많은 연구에서 프레임 슬롯 ALOHA 방식의 최대 시스템 효율은 36.8%임을 나타내고 있다. 본 논문에서는 기존의 프레임슬롯 알로하 보다 개선된 태그 수집성능 위해 RFID 시스템에 정합하는 efficient slotted CSMA/CA를 제안한다. IEEE 802.15.4 저 전력 센서 네트워크에서 널리 사용 중인 slotted CSMA/CA를 RFID 시스템에 적용하기 위한 프레임 구조를 제시하며, 주변의 태그 개수에 따라 유동적 프레임 사이즈 조절을 통한 수집성능을 향상한다. 실제 433MHz 능동형 RFID 리더와 태그 40대에서 실험을 통하여 제안한 slotted CSMA/CA가 프레임 슬롯 ALOHA 방식보다 태그 수집시간, 수집라운드 및 충돌 횟수에서 각각 18%, 37.4%, 77.8%의 성능향상을 보였다.

• 한국해양바이오학회지
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• 제5권4호
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• pp.40-45
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• 2011

Microalgae are one of the major, sustaining components of ecosystem processes and are responsible for biogeochemical reactions that drive our climate changes. Despite this, many marine microalgae are poorly described and little is known of their abundance and distribution along the coastal areas of Sooyoung Bay, Busan, South Korea. The present study has been conducted from November, 2011 to August, 2009 with the objective to provide an overview of the taxonomy diversity and abundance of microalgae along the coastal areas of the Sooyoung Bay. Water samples were collected from different sites, which were located by using a GPS tracker. Chlorophyll fluorescence of the water samples were measured by using ToxY-PAM dual-channel yield analyzer. The chlorophyll fluorescence values were relatively higher during the spring and summer and even in the region near to the sea port. Similarly the abundance of microalgae was higher near the port but diversity index had lower values. The temperature and pH values were same at all the sites. However, only the temperature varied during the sampling period, with higher values during summer and lower in winter. From the preliminary results, the following class of microalgae were found; Bacillariophyceae, Dinophyceae, Silicoflagellate and Cryptophyceae. With a future ongoing work, microalgae are being isolated to establish single cell culture and for identification using light microscopic observations, photography and molecular approaches.

• Nuclear Engineering and Technology
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• 제53권10호
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• pp.3406-3412
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• 2021

A real-time digital time-stamp sorting algorithm used in the In-Beam positron emission tomography (In-Beam PET) is presented. The algorithm is operated in the field programmable gate array (FPGA) and a small amount of registers, MUX and memory cells are used. It is developed for sorting the data of annihilation event from front-end circuits, so as to identify the coincidence events efficiently in a large amount of data. In the In-Beam PET, each annihilation event is detected by the detector array and digitized by the analog to digital converter (ADC) in Data Acquisition Unit (DAQU), with a resolution of 14 bits and sampling rate of 50 MS/s. Test and preliminary operation have been implemented, it can perform a sorting operation under the event count rate up to 1 MHz per channel, and support four channels in total, count rate up to 4 MHz. The performance of this algorithm has been verified by pulse generator and ²²Na radiation source, which can sort the events with chaotic order into chronological order completely. The application of this algorithm provides not only an efficient solution for selection of coincidence events, but also a design of electronic circuit with a small-scale structure.

• Asian-Australasian Journal of Animal Sciences
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• 제31권12호
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• pp.1852-1862
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• 2018

Objective: The purpose of this study was to investigate a single step genome-wide association study (ssGWAS) for identifying genomic regions affecting reproductive traits in Landrace and Large White pigs. Methods: The traits included the number of pigs weaned per sow per year (PWSY), the number of litters per sow per year (LSY), pigs weaned per litters (PWL), born alive per litters (BAL), non-productive day (NPD) and wean to conception interval per litters (W2CL). A total of 321 animals (140 Landrace and 181 Large White pigs) were genotyped with the Illumina Porcine SNP 60k BeadChip, containing 61,177 single nucleotide polymorphisms (SNPs), while multiple traits single-step genomic BLUP method was used to calculate variances of 5 SNP windows for 11,048 Landrace and 13,985 Large White data records. Results: The outcome of ssGWAS on the reproductive traits identified twenty-five and twenty-two SNPs associated with reproductive traits in Landrace and Large White, respectively. Three known genes were identified to be candidate genes in Landrace pigs including retinol binding protein 7, and ubiquitination factor E4B genes for PWL, BAL, W2CL, and PWSY and one gene, solute carrier organic anion transporter family member 6A1, for LSY and NPD. Meanwhile, five genes were identified to be candidate genes in Large White, two of which, aldehyde dehydrogenase 1 family member A3 and leucine rich repeat kinase 1, associated with all of six reproduction traits and three genes; retrotransposon Gag like 4, transient receptor potential cation channel subfamily C member 5, and LHFPL tetraspan subfamily member 1 for five traits except W2CL. Conclusion: The genomic regions identified in this study provided a start-up point for marker assisted selection and estimating genomic breeding values for improving reproductive traits in commercial pig populations.

• The Korean Journal of Physiology and Pharmacology
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• 제23권5호
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• pp.357-366
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• 2019

$G{\alpha}_q$-coupled receptor stimulation was implied in the activation process of transient receptor potential canonical (TRPC)1/4 and TRPC1/5 heterotetrameric channels. The inactivation occurs due to phosphatidylinositol 4,5-biphosphate ($PI(4,5)P_2$) depletion. When $PI(4,5)P_2$ depletion was induced by muscarinic stimulation or inositol polyphosphate 5-phosphatase (Inp54p), however, the inactivation by muscarinic stimulation was greater compared to that by Inp54p. The aim of this study was to investigate the complete inactivation mechanism of the heteromeric channels upon $G{\alpha}_q$-phospholipase $C{\beta}$ ($G{\alpha}_q-PLC{\beta}$) activation. We evaluated the activity of heteromeric channels with electrophysiological recording in HEK293 cells expressing TRPC channels. TRPC1/4 and TRPC1/5 heteromers undergo further inhibition in $PLC{\beta}$ activation and calcium/protein kinase C (PKC) signaling. Nevertheless, the key factors differ. For TRPC1/4, the inactivation process was facilitated by $Ca^{2+}$ release from the endoplasmic reticulum, and for TRPC1/5, activation of PKC was concerned mostly. We conclude that the subsequent increase in cytoplasmic $Ca^{2+}$ due to $Ca^{2+}$ release from the endoplasmic reticulum and activation of PKC resulted in a second phase of channel inhibition following $PI(4,5)P_2$ depletion.