Extremely sensitive and selective sub-ppm CO detection by the synergistic effect of Au nanoparticles and core–shell nanowires

Kim, Jae-Hun,Mirzaei, Ali,Kim, Hyoun Woo,Kim, Sang Sub Elsevier Sequoia 2017 Sensors and actuators. B Chemical Vol.249 No.-

<P><B>Abstract</B></P> <P>An extremely sensitive CO sensor based on novel hybrid SnO<SUB>2</SUB>–ZnO core–shell (C–S) nanowires (NWs) functionalized by Au nanoparticles (NPs) was synthesized. First, networked SnO<SUB>2</SUB> NWs were successfully prepared using the vapor–liquid–solid growth method on an electrode layer with special patterns. A ZnO shell was subsequently coated on the SnO<SUB>2</SUB> core using atomic layer deposition, and Au NPs were then attached onto the ZnO shell using γ-ray radiolysis. The resulting sensor exhibited a very high response of 26.6–100ppb CO gas. Furthermore, the responses to other gases such as C<SUB>6</SUB>H<SUB>6</SUB> and C<SUB>6</SUB>H<SUB>7</SUB> were extremely low, indicating the very good selectivity of the sensor to CO gas. Besides acting as heterojunctions, the catalytic effect of the Au NPs on CO gas greatly improved the CO sensing capability of the Au-functionalized SnO<SUB>2</SUB>–ZnO C–S NWs. The high sensitivity and selectivity of this sensor can open a path for prompt toxic monitoring and early detection of fatal diseases related to CO.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel hybrid SnO<SUB>2</SUB>–ZnO core–shell nanowires functionalized by Au nanoparticles. </LI> <LI> The resulting sensor exhibited a very high response of 26.6–100ppb CO gas. </LI> <LI> The very good selectivity of the sensor to CO gas. </LI> <LI> Heterojunctions and the catalytic effect of Au greatly improved the CO sensing capability. </LI> </UL> </P>

입내 분산형 Al₂O₃/Ag 나노복합체의 제조와 특성

천승호,한인섭,히데오 아와지,Cheon, Sung-Ho,Han, In-Sub,Awaji, Hideo 한국세라믹학회 2007 한국세라믹학회지 Vol.44 No.4

Alumina/silver ($Al_2O_3/Ag$) nanocomposites with Ag content up to 9 vol% were prepared from nanopowder by soaking method using ${\gamma}-Al_2O_3$ of needle type and spark plasma sintering (SPS). The mechanical properties of specimens were investigated three-point flexural strength and toughness as a function of the Ag contents. The maximum flexural strength of the alumina/silver nanocomposite was 850 MPa for the 1 vol% composite, and also higher than monolith alumina as about 800 MPa at 3, 5, and 7 vol% Ag contents. Fracture toughness by single edged V-notch beam (SEVNB) was $4.05MPa{\cdot}m^{1/2}$ for the 3 vol% composite and maintained about $4.00MPa{\cdot}m^{1/2}$ at 5, and 7 vol% Ag content. Microstructure of fracture surface for each fracture specimens was observed. Due to the inhibition effect of alumina grain growth, the average grain size of nanocomposites depends on the content of Ag nano particles. The fracture morphology of nanocomposite with dislocation (sub-grain boundary) by silver nano-particles of second phases in the alumina matrix also showed transgranular fracture-mode compare with intergranular of monolith alumina. Thermal conductivity of specimens at room temperature was about 40 W/mK for the 1 vol% Ag content.

SPIM 벡터제어를 위한 태양광 발전 시스템

고재섭(Jae-Sub Ko),최정식(Jung-Sik Choi),정병진(Byung-Jin Jung),김도연(Do-Yeon Kim),박기태(Ki-Tae Park),최정훈(Jung-Hoon Choi),정동화(Dong-Hwa Chung) 한국조명·전기설비학회 2007 한국조명·전기설비학회 학술대회논문집 Vol.2007 No.11월

This paper presents the photovoltaic(PV) water pumping system with a maximum power point tracking(MPPT). The water pumping system uses a variable speed single phase induction motor(SPIM) driven a centrifugal pump by field oriented control(FOC) inverter. The MPPT using a DC-DC converter controlled the duty cycle to track maximum power from PV under different insolation conditions. The duty cycle directly relate with a flux producing current control(i<SUB>ds</SUB>). The FOC inverter uses a current control voltage source inverter(CC-VSI). The simulation results are shown that the characteristics and performance of drive system, which varies as each conditions of light by expresses in voltage(V<SUB>dq</SUB>), current(I<SUB>dq</SUB>), speed of motor and torque.

A Synthetic Naringenin Derivative, 5-Hydroxy-7,4′-diacetyloxyflavanone-<i>N</i>-phenyl Hydrazone (N101-43), Induces Apoptosis through Up-regulation of Fas/FasL Expression and Inhibition of PI3K/Akt Signaling Pathways in Non-Small-Cell Lung Cancer Cells

Bak, Yesol,Kim, Heejong,Kang, Jeong-Woo,Lee, Dong Hun,Kim, Man Sub,Park, Yun Sun,Kim, Jung-Hee,Jung, Kang-Yeoun,Lim, Yoongho,Hong, Jintae,Yoon, Do-Young American Chemical Society 2011 Journal of agricultural and food chemistry Vol.59 No.18

<P>Naringenin, a well-known naturally occurring flavonone, demonstrates cytotoxicity in a variety of human cancer cell lines; its inhibitory effects on tumor growth have spurred interest in its therapeutic application. In this study, naringenin was derivatized to produce more effective small-molecule inhibitors of cancer cell proliferation, and the anticancer effects of its derivative, 5-hydroxy-7,4′-diacetyloxyflavanone-<I>N</I>-phenyl hydrazone (N101-43), in non-small-cell lung cancer (NSCLC) cell lines NCI-H460, A549, and NCI-H1299 were investigated. Naringenin itself possesses no cytotoxicity against lung cancer cells. In contrast, N101-43 inhibits proliferation of both NCI-H460 and A549 cell lines; this capacity is lost in p53-lacking NCI-H1299 cells. N101-43 induces apoptosis via sub-G<SUB>1</SUB> cell-cycle arrest in NCI-H460 and via G<SUB>0</SUB>/G<SUB>1</SUB> arrest in A549 cells. Expression of apoptosis and cell-cycle regulatory factors is altered: Cyclins A and D1 and phospho-pRb are down-regulated, but expression of CDK inhibitors such as p21, p27, and p53 is enhanced by N101-43 treatment; N101-43 also increases expression levels of the extrinsic death receptor Fas and its binding partner FasL. Furthermore, N101-43 treatment diminishes levels of cell survival factors such as PI3K and p-Akt dose-dependently, and N101-43 additionally induces cleavage of the pro-apoptotic factors caspase-3, caspase-8, and poly ADP-ribose polymerase (PARP). Cumulatively, these investigations show that the naringenin derivative N101-43 induces apoptosis via up-regulation of Fas/FasL expression, activation of caspase cascades, and inhibition of PI3K/Akt survival signaling pathways in NCI-H460 and A549 cells. In conclusion, these data indicate that N101-43 may have potential as an anticancer agent in NSCLC.</P>

Multi-dimensional Perfectionism Tendencies and Self-management of Kendo players on Status Confidence and Performance Satisfaction

( Sang Sub Park ),( Seung Hyun Lim ) 국제태권도학회 2017 International Symposium for Taekwondo Studies Vol.2017 No.-

Purpose: The purpose of this study is to examine the impact of perfectionism tendencies and self-management of high school Kendo players on status confidence satisfaction. Methods: In order to achieve the purpose of this study, 220 Kendo players who participated in the Daegu University President’s National High School Kendo Championship were examined. Reliability, correlation analysis, and multiple-regression analysis were conducted on the collected data using SPSS 18.0. Results: First, it was found that there was a positive correlation in self-management, status confidence, and performance satisfaction in high school Kendo players. Second, it was found that among the sub-factors of multi-dimensional perfectionism tendencies, criticism from important others had a positive impact on status confidence. Third, it was found that among the sub-factors of multi-dimensional perfectionism tendencies, concerns on mistakes had a positive impact on instructor satisfaction. Fourth, among the sub-factors of self-management, it was found that training management and personal relationship management had a positive impact on status confidence. Fifth, among the sub-factors of self-management, it was found that personal relationship management and mental management had a positive impact on match performance satisfaction. Sixth, among the sub-factors of self-management, it was found that training management and mental management had a positive impact on instructor satisfaction.

검도선수들의 다차원완벽주의 성향과 자기관리가 상태자신감 및 경기만족에 미치는 영향

박상섭(Park, Sang-Sub),남경완(Nam, Kyung-Wan),임승현(Lim, Seung-Hyun) 한국체육과학회 2017 한국체육과학회지 Vol.26 No.3

The purpose of this study was to examine the impact of perfectionism tendencies and self-management of high school kendo fencers on status confidence and performance satisfaction. In order to achieve the purpose of this study, 220 kendo fencers who participated in the Daegu University President"s National High School Kendo Championship were examined. Reliability, correlation analysis and multiple-regression analysis was conducted on the collected data using SPSS 18.0. The results are as follows. First, it was found that there was a positive (+) correlation in self-management, status confidence and performance satisfaction in high school kendo fencers. Second, it was found that among the sub-factors of multi-dimensional perfectionism tendencies, criticism of important others had a positive impact on status confidence. Third, it was found that among the sub-factors of multi-dimensional perfectionism tendencies, concerns on mistakes had a positive impact on instructor satisfaction. Fourth, among the sub-factors of self-management, it was found that training management and personal relationship management had a positive impact on status confidence. Fifth, among the sub-factors of self-management, it was found that personal relationship management and mental management had a positive impact on match performance satisfaction. Sixth, among the sub-factors of self-management, it was found that training management and mental management had a positive impact on instructor satisfaction.

A Minimal Error Sub-Space Recognition Method using 3D Reconstruction from Multi Image Frames

Dongjin Han(한동진),We Sub Eom(엄위섭),Hern-soo Hahn(한헌수) 대한전자공학회 2010 대한전자공학회 학술대회 Vol.2010 No.6

We propose a new recognition method which minimizes the affect of the 3D error of stereo reconstruction or video reconstruction. After 3D structure of an object is found via any Structure from Motion (SfM) method, 2D recognizers will be implemented on the minimal error sub-space of the object"s 3D reconstruction. For each image frame from either stereo images or video clips, the best 2D sub-space recognizer is determined by projecting objects original 3D (CAD) models onto each individual image frame"s 2D sub-space. Compared to the previous work [1] where 3D reconstruction was directly used for recognition, sub-space method will use sub-space to minimized the influence of the unknown 3D triangulation error.

스포츠클럽 참여하는 중학생들의 신체적 자기개념이 학교생활만족도에 미치는 영향

박준억, 박상섭, 정재원 忠北大學校 平生體育硏究所 2015 平生體育硏究所 論文集 Vol.27 No.-

The purpose of this study is to investigate the effect of physical self-concept and school life satisfaction of middle School students participating in sports clubs. To achieve this purpose, male and female middle school students participating in sports clubs in the C area in 2015 using a convenience sampling method were aimed to collect data. The data was subjected to factor analysis, reliability analysis and correlation and regression analysis using the SPSS 19.0 program, The results are as follows. First, the fitness had significant influence among physical self-concepts of the sub-factors on satisfaction school life satisfaction, teacher relationships, and physical behavior. Secondly, the flexibility, of the sub-factors among physical self-concepts of sub-factors had significant influence on the subordinate relationship between teachers which is the sub-factors of school life satisfaction. Third, the health, and appearance, among physical self-concepts of sub-factors had significant influence on the physical environment of sub-factors of the school life satisfaction.

체육수업에 대한 교과 흥미도가 학생들의 학업열의에 미치는 영향

이상섭(Lee, Sang-Sub),조홍식(Cho, Hong-Sik) 한국체육과학회 2015 한국체육과학회지 Vol.24 No.1

The purpose of this study was to investigate the effects of subject interest in physical education classes on academic engagement among students. For that purpose, the investigator found the population in middle and high school students in Gyeonggi Province and sampled 420 students through convenience sampling. Collected data were put to multiple regression analysis with the PASW Version 18 .0 statistical program. The findings were as follows: First, all the sub-factors of subject interest in physical education classes had statistically significant effects on academic engagement(efficacy). Second, all the sub-factors of subject interest in physical education classes had statistically significant effects on academic engagement(commitment) . Third, all the sub-factors of subject interest in physical education classes had statistically significant effects on academic engagement (vitality). Finally, all the sub-factors of subject interest in physical education classes had statistically significant effects on academic engagement (absorption)

Multi-mode Kernel Weight-based Object Tracking

Eun-Sub Kim(김은섭),Yong-Goo Kim(김용구),Yoo-Joo Choi(최유주) 한국컴퓨터그래픽스학회 2015 컴퓨터그래픽스학회논문지 Vol.21 No.4

최근, 감시시스템, 게임, 영화 등 다양한 분야에서 영상을 이용한 실시간 객체 추적의 필요성이 높아짐에 따라, 커널기반 mean-shift 추적 기법에 대한 관심이 높아지고 있다. 커널 기반 mean-shift 객체 추적에 있어서 주요한 몇 가지 문제점들 중, 첫 번째로 추적 목표 객체에 대한 부분 가림 혹은 전체 가림 상황에서의 객체 추적의 문제를 들 수 있다. 본 논문에서는 멀티모드 지역적 커널 가중치를 적용함으로써 부분 가림 상황에서도 안정적으로 객체를 추적할 수 있는 실시간 mean-shift 추적 기법을 제안한다. 제안기법에서는 단일 커널을 사용하는 대신 여러 개의 서브 커널들로 구성된 커널을 사용하고, 각 서브 커널의 위치에 따른 지역적 커널 가중치를 적용한다. 기존의 멀티모드 커널 기반의 방법과 비교한 실험을 통하여 본 제안 방법이 보다 안정적으로 객체를 추적할 수 있음을 보였다. As the needs of real-time visual object tracking are increasing in various kinds of application fields such as surveillance, entertainment, etc., kernel-based mean-shift tracking has received more interests. One of major issues in kernel-based mean-shift tracking is to be robust under partial or full occlusion status. This paper presents a real-time mean-shift tracking which is robust in partial occlusion by applying multi-mode local kernel weight. In the proposed method, a kernel is divided into multiple sub-kernels and each sub-kernel has a kernel weight to be determined according to the location of the sub-kernel. The experimental results show that the proposed method is more stable than the previous methods with multi-mode kernels in partial occlusion circumstance.