• Title/Summary/Keyword: CO sensing

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Climatological Estimation of Sea Surface CO2 Partial Pressure in the North Pacific Oceans by Satellite data

  • Osawa, Takahiro;Akiyama, Masatoshi;Sugimori, Yasuhiro
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.237-242
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    • 1999
  • As one of the key parameters to determine $CO_2$ flux between air - sea interface, it is quite important to know p$CO_2$, which has involved much uncertainty, mainly due to the complex variations of sea surface p$CO_2$ and the paucity of samples, made in ocean. In order to improve the interrelationship between partial pressure (p$CO_2$) and different physical and biochemical parameters in global sea surface water, a new empirical relation is established to correlate and parameterize p$CO_2$ in the mixed layer using the data from recent WOCE cruises. Meanwhile, by new empirical relation, abundant historical hydrographic and nutrients ship data, Levitus data set and NOAA/AVHRR(SST), p$CO_2$ have been accumulated and applied. Then effort has to be made fur promotion of this study to correlate and parameterize p$CO_2$ in the mixed Layer with different physical and biochemical parameters. and further attribute this huge historical data sets and NOAA/AVHRR(SST) data to estimate p$CO_2$. In this paper we analyzed more interrelationship between the model and ship/satellite data set. Finally, the inter-annual variations of p$CO_2$ in sea are presented and discussed.

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The CO sensing properties of thick film gas sensor using Co3O4 powders prepared by hydrothermal reaction method (수열합성법으로 제조된 Co3O4 분말을 사용한후막 가스센서의 CO 감지 특성)

  • Kim, Kwang-Hee;Kim, Jeong-Gyoo;Park, Ki-Cheol
    • Journal of Sensor Science and Technology
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    • v.19 no.5
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    • pp.385-390
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    • 2010
  • CO sensing thick film gas sensors using $Co_3O_4$ powders prepared by hydrothermal reaction method, were fabricated, and their structural, electrical and CO gas sensing properties were investigated. The specific surface area of the $Co_3O_4$ powders obtained from BET analysis was about 79.0 $m^2/g$. XRD and SEM results show that the thick films heat-treated at $500^{\circ}C$ for 30 min after screen printing had the preferred orientation of (311) direction and the crystalline size was calculated to 221 $\AA$. The maximum activation energy obtained from the temperature-resistance characteristics was 3.11 eV in the temperature range of $290^{\circ}C$ to $310^{\circ}C$. The sensitivity to 1,000 ppm CO was about 150 %. The specific surface area, crystalline size, and maximum activation energy were increased significantly and the sensitivity for CO gas was improved largely.

The Effect of Customer and Competitor Market Sensing Capability on Business Performance of SMEs: An Empirical Study in Indonesia

  • NURHAYATI, Tatiek;HENDAR, Hendar
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.8
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    • pp.601-612
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    • 2021
  • The purpose of this study is to investigate and examine the role of specialized marketing capabilities (SMC) in mediating the relationship between customer sensing capability (CuSC) and competitor sensing capability (CoSC) with business performance (BP) at SMEs retail fashion in Indonesia. This study used 330 SMEs from ten regencies in Indonesia and examined the regression relationship between the four variables, SMC, CuSC, CoSC, and BP. Confirmatory factor analysis (CFA) was used to measure the validity and reliability of the construct used. For data analysis techniques, this study used structural equation modeling (SEM) with AMOS Version 22.0. This study found that SMC acts as a partial mediator in the relationship between CuSC and CoSC with SMC and BP. By examining the diverse literature on market sensing capability, marketing strategy, and BP, this study offers a unique analysis of market learning and its effects on SMC and BP in Retail Fashion SMEs in Indonesia. Furthermore, future research needs to broaden the findings and improve generalizations by conducting studies of SMEs in other industries, such as manufacturing, and services of small, medium and large scale. In addition, it needs to add some countries as research objects, not only Indonesia.

CO Sensor Characteristics of ZnO powders by Sol-Gel methods (Sol-Gel법에 의한 ZnO 분말의 CO 센서 특성)

  • Park, Bo-Seok;Park, Jin-Seoung;Noh, Whyo-Sub
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.821-825
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    • 2002
  • ZnO thick films by Sol-Gel processing were investigated electrics, optics and the sensing characteristics of CO gas. Using the znic acetate dihydrate and acetylaceton (AcAc) as a chelating agent, stable ZnO sol was synthesized. ZnO phase was crystallized through the heat-treatment at $70^{\circ}C$ for 4hrs and influenced the sensing characteristics of the electrics and CO gas by uniform particle distributions not related particle size. The samples on the alumina substrate by thick films were investigated the properties of electrics and the effect of sensing. The sensitivity was so excellent in the sample of the heat-treatment at $600^{\circ}C$ for 12hrs and good in the heat-treatment for 1hrs generally. Crystallization and volatilization of organic materials according to the change of heating treatment temperature of thick films were analyzed by TG-DTA, XRD and mirostructure of thick films were observed by SEM.

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Novel Compressed Sensing Techniques for Realistic Image (실감 영상을 위한 압축 센싱 기법)

  • Lee, Sun Yui;Jung, Kuk Hyun;Kim, Jin Young;Park, Gooman
    • Journal of Satellite, Information and Communications
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    • v.9 no.3
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    • pp.59-63
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    • 2014
  • This paper describes the basic principles of 3D broadcast system and proposes new 3D broadcast technology that reduces the amount of data by applying CS(Compressed Sensing). Differences between Sampling theory and the CS technology concept were described. Recently proposed CS algorithm AMP(Approximate Message Passing) and CoSaMP(Compressive Sampling Matched Pursuit) were described. This paper compared an accuracy between two algorithms and a calculation time that image data compressed and restored by these algorithms. As result determines a low complexity algorithm for 3D broadcast system.

Effects of Co Doping on NO Gas Sensing Characteristics of ZnO-Carbon Nanotube Composites (산화아연-탄소나노튜브 복합체의 일산화질소 가스 감지 특성에 미치는 코발트 첨가 효과)

  • Jung, Hoon-Chul;Ahn, Eun-Seong;Hung, Nguyen Le;Oh, Dong-Hoon;Kim, Hyo-Jin;Kim, Do-Jin
    • Korean Journal of Materials Research
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    • v.19 no.11
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    • pp.607-612
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    • 2009
  • We investigated the effects of Co doping on the NO gas sensing characteristics of ZnO-carbon nanotube (ZnO-CNT) layered composites fabricated by coaxial coating of single-walled CNTs with ZnO using pulsed laser deposition. Structural examinations clearly confirmed a distinct nanostructure of the CNTs coated with ZnO nanoparticles of an average diameter as small as 10 nm and showed little influence of doping 1 at.% Co into ZnO on the morphology of the ZnO-CNT composites. It was found from the gas sensing measurements that 1 at.% Co doping into ZnO gave rise to a significant improvement in the response of the ZnO-CNT composite sensor to NO gas exposure. In particular, the Co-doped ZnO-CNT composite sensor shows a highly sensitive and fast response to NO gas at relatively low temperatures and even at low NO concentrations. The observed significant improvement of the NO gas sensing properties is attributed to an increase in the specific surface area and the role as a catalyst of the doped Co elements. These results suggest that Co-doped ZnOCNT composites are suitable for use as practical high-performance NO gas sensors.

CO Gas Sensing Characteristics of Nanostructured ZnO Thin Films (산화아연 나노구조 박막의 일산화탄소 가스 감지 특성)

  • Hung, Nguyen Le;Kim, Hyo-Jin;Kim, Do-Jin
    • Korean Journal of Materials Research
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    • v.20 no.5
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    • pp.235-240
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    • 2010
  • We investigated the carbon monoxide (CO) gas-sensing properties of nanostructured Al-doped zinc oxide thin films deposited on self-assembled Au nanodots (ZnO/Au thin films). The Al-doped ZnO thin film was deposited onto the structure by rf sputtering, resulting in a gas-sensing element comprising a ZnO-based active layer with an embedded Pt/Ti electrode covered by the self-assembled Au nanodots. Prior to the growth of the active ZnO layer, the Au nanodots were formed via annealing a thin Au layer with a thickness of 2 nm at a moderate temperature of $500^{\circ}C$. It was found that the ZnO/Au nanostructured thin film gas sensors showed a high maximum sensitivity to CO gas at $250^{\circ}C$ and a low CO detection limit of 5 ppm in dry air. Furthermore, the ZnO/Au thin film CO gas sensors exhibited fast response and recovery behaviors. The observed excellent CO gas-sensing properties of the nanostructured ZnO/Au thin films can be ascribed to the Au nanodots, acting as both a nucleation layer for the formation of the ZnO nanostructure and a catalyst in the CO surface reaction. These results suggest that the ZnO thin films deposited on self-assembled Au nanodots are promising for practical high-performance CO gas sensors.

Development of SWIR 3D Lidar System with Low Optical Power Using 1 Channel Single Photon Detector (1채널 단일광자검출기를 이용한 낮은 광출력의 SWIR(Short Wave Infrared) 3D 라이다 시스템 개발)

  • Kwon, Oh-Soung;Lee, Seung-Pil;Shin, Seung-Min;Park, Min-Young;Ban, Chang-Woo
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.6_3
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    • pp.1147-1154
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    • 2022
  • Now that the development of autonomous driving is progressing, LiDAR has become an indispensable element. However, LiDAR is a device that uses lasers, and laser side effects may occur. One of them is the much-talked-about eye-safety, and developers have been satisfying this through laser characteristics and operation methods. But eye-safety is just one of the problems lasers pose. For example, irradiating a laser with a specific energy level or higher in a dusty environment can cause deterioration of the dust particles, leading to a sudden explosion. For this reason, the dust ignition proof regulations clearly state that "a source with a pulse period of less than 5 seconds is considered a continuous light source, and the average energy does not exceed 5 mJ/mm 2 or 35 mW" [2]. Energy of output optical power is limited by the law. In this way, the manufacturer cannot define the usage environment of the LiDAR, and the development of a LiDAR that can be used in such an environment can increase the ripple effect in terms of use in application fields using the LiDAR. In this paper, we develop a LiDAR with low optical power that can be used in environments where high power lasers can cause problems, evaluate its performance. Also, we discuss and present one of the directions for the development of LiDAR with laser power limited by dust ignition proof regulations.