• Title/Summary/Keyword: Humidity measurement

Search Result 468, Processing Time 0.039 seconds

Development of a Wireless, Battery-free SAW-based Temperature and Humidity Sensor incorporating a Bidirectional Reflective Delay Line (양방향 반사 지연선을 이용한 무선, 무전원 SAW 기반 온, 습도 센서 개발)

  • Lim, Chun-Bae;Lee, Kee-Keun
    • Proceedings of the KIEE Conference
    • /
    • 2009.07a
    • /
    • pp.1515_1516
    • /
    • 2009
  • A 440MHz wireless and passive surface acoustic wave (SAW) based micro-sensor was developed for simultaneous measurement of temperature and humidity. The developed sensor is composed of a SAW reflective delay lines structured by an IDT (Inter-Digital Transducer), four reflectors and humidity sensitive film (polyimide). Polyimide was dry-ecthed by RIE (Reactive Ion Etching) to obtain high roughness, which gives the large reaction area resulting in high sensitivity. In wireless testing using a network analyzer, sharp reflection peaks with high S/N ratio, small signal attenuation, and few spurious peaks were observed in the time domain. High sensitivity towards the temperature and humidiy were also observed in the large concentration range. The obtained sensitivity was $16.8^{\circ}/^{\circ}C$ for temperature sensor and $15.8^{\circ}$/%RH for humidity sensor.

  • PDF

Development of Capacitance-type Humidity Sensors Using Porous Silicon Layer (다공질 실리콘층을 이용한 정전용량형 습도센서의 개발)

  • Kim, Seong-Jeen;Lee, Ju-Hyuk;Yoon, Yeo-Kyung;Choi, Bok-Gil
    • Proceedings of the KIEE Conference
    • /
    • 1998.11c
    • /
    • pp.1014-1016
    • /
    • 1998
  • A capacitance-type humidity sensor using porous silicon layer is developed. The unique property of this sensor is a structure which has electrodes on the surface of the wafer like a general IC device. To do this. the sensor was fabricated using process such as localized formation of porous silicon, oxidation of porous silicon layer, and etching of oxidized porous silicon layer. The measurement of humidity-sensing ability was done for two type of sensors using porous silicon layer formed in 25 and 35% HF solutions, respectively. As the result, the former sensors showed larger value and variation of capacitance for the relative humidity.

  • PDF

A Study on the Effect of Storing Temperature and Humidity upon the Self Life of Propellant KM30Al (추진제 KM30Al의 저장 온도/습도와 저장수명과 관계 고찰)

  • Cho, Ki-Hong
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.9 no.1 s.24
    • /
    • pp.13-23
    • /
    • 2006
  • A propellant mainly consisting of nitric ester including nitrocellulose and nitroglycerine is characteristic of being decomposed naturally. And this phenomenon is known as being affected mostly by its storing temperature and humidity. In this research, the effect of storing temperature and humidity on self life has been studied by measuring the contained quantity of residual stabilizer of propellant KM30Al, which are parts of 155MM propelling charge K676 and K677; the method for the measurement is acceleration aging test, and decomposition reaction equation, Eyring Equation and Berthlot Equation were used for the calculation. As result of this study, it was found that the storing temperature influenced seven times as large as the storing humidity upon the self life of the propellant KM30Al, Furthermore, especially in the high temperature region, the storing temperature had a dominant effect on the self life.

Prediction Model for the Change of Temperature and R.H. inside Reinforced Concrete (철근콘크리트 내부 온습도 경시변화 추정 모델 구축)

  • Park, Dong-Cheon
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2016.10a
    • /
    • pp.83-84
    • /
    • 2016
  • Surplus water inside a concrete other than moisture that is used for hydration of the cement affects the physical properties of the concrete (modulus of elasticity, compressive strength, drying shrinkage, and creep) by drying. Changes in temperature and humidity inside a concrete has correlation with the movement speed and reaction rate of deterioration factors such as carbon dioxide and chloride ions. In this study, comparison was performed between temperature and relative humidity inside the concrete and meteorological data for exposure environment through measurement at the site for two years. Surface temperature of the concrete (depth 1cm) was measured higher by 6℃ during the summers, while it was measured lower by 2℃ during the winters due to solar radiation, wind, and radiation cooling. As for relative humidity, change was large in the depth of 1cm, while more than 85% was maintained in the depth of 10cm.

  • PDF

Design and implementation of thermoelectric dehumidifier using pottier module (Pottier소자를 이용한 열전 제습기 설계 및 구현)

  • 장재철;양규식
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.3 no.3
    • /
    • pp.671-679
    • /
    • 1999
  • In this paper, humidity measurement is accomplished using humidity sensor, dehumidify is implemented using general-purpose $\mu$-processorPIC16C54 and thermoelectric module for control measured humidity and input target humidity value proportionally Pottier module product is variety kind of size and characteristic, very important drawing factor is selection necessary heat sink, which is maintain proper thermal resistance from variety kind of module also. From electronic dehumidifier is manufacture by using thermoelectric module, no sound, no vibration, low power consumption of partial space efficient dehumidify proves the validity of this system.

  • PDF

Measurement of Transpiration Rate of Apple with a Microcomputer-Based Data Acquisition System during CA Storage (마이크로컴퓨터 시스템을 이용한 CA 저장 중 사과의 증산속도 측정)

  • 강준수;서명교
    • Food Science and Preservation
    • /
    • v.1 no.1
    • /
    • pp.37-43
    • /
    • 1994
  • A microcomputer system consisting of 16-bit microcomputer, PCL-711S interface board, censors, and converters have been set up in order to automatically measure temperature, humidity and weight loss which are major variables of storage of apple. This system was operated by PC-LabDAS software. It has been possible to measure continuously the weight loss of Fuji apple stored in CA with the weight converter made by a miniature load cell and a strain amplifier. The temperature was checked by a k-type thermocouple and Pt 100 $\Omega$ RTD, and humidity by PQ653JAl humidity sensor. It has been possible to set up a linear equation which showers high correlationship between the estimate of temperature, weight humidity and the output of the converter in that r2 is more than 0.99. Transpiration rate, a significant factor of quality deterioration for CA storage of apple, can be estimated with these values.

  • PDF

The $CH_4$and $C_4$$H_{10}$ Sensitivity Measurement and Voltage Variation Using Catalytic Combustion Type Gas Sensor (접촉연소식 센서를 이용한 $CH_4$$C_4$$H_{10}$ 감도 측정 및 전압변화)

  • 윤헌주;신종열;홍진웅
    • Fire Science and Engineering
    • /
    • v.15 no.3
    • /
    • pp.44-48
    • /
    • 2001
  • In this study, we analyzed the $CH_4$and $C_4$$H_{10}$ sensitivity measurement and voltage variation using catalytic type gas sensor characteristics in catalytic combustion type gas detecter sensors. Gas detector shall operate as intended when exposed for 24 hours to air having a relative humidity of 65 percent at a temperature of $20^{\circ}c$ and humidity of 85 percent at a temperature of $40^{\circ}c$. The gas detecter sensors are to be subjected to operation for 210 days in an area that has been determined to be equivalent to a typical residential atmosphere with an air velocity of 50 cm/sec. The source of energy for a gas detector sensors employing a supplementary basic circuit is energized from a seperate source of supply direct applied voltage 2.1V, 2.2V, 2.3V. As a result, it was confirmed that the relative humidity and temperature by regression each analysis, compared to the isobutane characteristic graph and methane characteristic graph by a relative humidity of 65% and 85% at a temperature($20^{\circ}c$, $40^{\circ}c$) show a similar linear pattern on the whore.

  • PDF

Evapotranspiration Rate of Grafted Seedlings Affected by Relative Humidity and Photosynthetic Photon Flux under Artificial Lighting (인공광하에서 접목묘의 증발산속도에 미치는 상대습도와 광합성유효광량자속의 효과)

  • 김용현;박현수
    • Journal of Biosystems Engineering
    • /
    • v.26 no.4
    • /
    • pp.379-384
    • /
    • 2001
  • To enhance the smooth graft-taking of grafted seedlings, the excessive evapotranspiration from grafted seedlings just after grafting should be avoided. A measurement system of the evapotranspiration rate of grafted seedling under artificial lighting was set up to investigate the effect of physical environment on the evapotranspiration and graft-taking characteristics of grafted seedlings quantitatively. The evapotranspiration rate of grafted seedlings affected by relative humidity and light intensity were analyzed using the measurement system. The hypocotyl of watermelons (Citrullus vulgaris cv. Sweetdew, Hungnong Seed Co.) was slantly cut and then inserted into a hole on the stem of rootstock (Lagenaria siceraria cv. FR-King, Hungnong Seed Co.). Grafted seedlings were healed and joined for 5 days under cool-white fluorescent lamps (FL20SEX-d/18, Keumho Electric Co.) with photoperiod of 12h$.$d$\^$-1/ except dark period for one day after grafting in a closed graft-taking enhancement system developed by Kim(2000). The evapotranspiration rate and graft-taking of grafted seedling at air temperature of 23$\^{C}$ and air current speed of 0.1m$.$s$\^$-1/ was highly affected by relative humidity. But light intensity showed higher effect on the stem length of scion than relative humidity. In conclusion, it was suggested that relative humidity should be controlled at higher than 90% with photosynthetic photon flux of 50$\mu$mol$.$m$^2$$.$s$\^$-1/ to increase the survival of grafted seedlings and to produce healthy seedlings.

  • PDF

Application of computer vision for rapid measurement of seed germination

  • Tran, Quoc Huy;Wakholi, Collins;Cho, Byoung-Kwan
    • Proceedings of the Korean Society for Agricultural Machinery Conference
    • /
    • 2017.04a
    • /
    • pp.154-154
    • /
    • 2017
  • Root is an important organ of plant that typically lies below the surface of the soil. Root surface determines the ability of plants to absorb nutrient and water from the surrounding soil. This study describes an application of image processing and computer vision which was implemented for rapid measurement of seed germination such as root length, surface area, average diameter, branching points of roots. A CCD camera was used to obtain RGB image of seed germination which have been planted by wet paper in a humidity chamber. Temperature was controlled at approximately 250C and 90% relative humidity. Pre-processing techniques such as color space, binarized image by customized threshold, removal noise, dilation, skeleton method were applied to the obtained images for root segmentation. The various morphological parameters of roots were estimated from a root skeleton image with the accuracy of 95% and the speed of within 10 seconds. These results demonstrated the high potential of computer vision technique for the measurement of seed germination.

  • PDF

A Study of Constructing the Environment to Adjust the Humidity Automatically (농작물 육성에 필요한 습도 자동조절 환경 구축에 관한 연구)

  • Xu, Chen-lin;Lee, Hyun-chang;Shin, Seong-Yoon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2015.10a
    • /
    • pp.147-148
    • /
    • 2015
  • To achieve high-yield, high-quality and safely sustainable development of agricultural and establish the standardization of agricultural production, processing, circulation management system, scientific methods must be used. But in plastic greenhouse, the traditional manual measurement way is still used in cultivation and measurement of relative humidity. In order to improve the efficiency of farm work, to make agricultural production more modernization, this paper combining with the sensor and display device to build a environment which can automatically adjust the humidity.

  • PDF