• Title/Summary/Keyword: chemical communication

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Short term Sensor's Drift Compensation by using Three Drift Correction Techniques (세 가지 드리프트 보정 기법을 이용한 단기 센서 드리프트 보정)

  • Jeon, Jin-Young;Choi, Jang-Sik;Byun, Hyung-Gi
    • Journal of Sensor Science and Technology
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    • v.25 no.4
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    • pp.291-296
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    • 2016
  • The ideal chemical sensor must show the similar result under the same condition for accurate measurement of gases regardless of time. However, the actual responses of chemical sensors have been shown the lacks of repeatability and reproducibility because of the drift which has been caused by aging and pollution of the sensor and the environment change such as temperature and humidity. If the problems are not properly taken into considerations, the stability and reliability of the system using chemical sensors would be decreased. In this paper, we analyzed the sensor's drift and applied the three different compensation methods(DWT( Discrete Wavelets Transform), Baseline Manipulation, Internal Normalization) for reducing the effects of the drift in order to improve the stability and the reliability of short term of the chemical sensors. And in order to compare the results of the methods, the standard deviation was used as a criterion. The sensor drift was analyzed by a trend line graph. We applied the three methods to the successive data measured for three days and compared the results. As a result of comparison, the standard deviation of DWT showed lowest value. (Before compensation: 7.1219, DWT: 1.3644, Baseline Manipulation: 2.5209, Internal Normalization: 3.1425).

Study on Photochromism for Transition Metal Compounds by Using the Optieal Waveguide (광 도파관을 이용한 전이금속 화합물의 광색성연구)

  • SeeWooLee
    • Journal of the Korean Graphic Arts Communication Society
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    • v.10 no.1
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    • pp.1-13
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    • 1992
  • The recent results concerning the synthesis and application of spiroxazine dyes have been summerized., The absorption bands of usual spiroxazine dyes are changed from colorless to colored from by irradiation of ultraviolet ray. This mechanism is derived from the cleavage of oxazine ring. Such properties are dependent on its chemical structure and surrounded matrix of spiroxazine dyes. the chemical structure of this dye is similar to the well known spriopyran. But spiroxazine dyes have noticed recently, because of excellent high light-sensitivity and superior fatigue-resistant property. This dye are already applied as photochromic lens, cloths and UV light checker.

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Current and Future Prospects for Insect Behavior-modifying Chemicals in China

  • Du, Jia-Wei
    • Journal of Applied Biological Chemistry
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    • v.43 no.4
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    • pp.222-229
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    • 2000
  • In this paper we will assess the feasibility of some insect behavior-modifying chemicals for insect control, such as male orientation inhibitor, female calling interrupter and female attractant of cotton bollworm Helicoverpa armigera. These behavior-modifying chemicals have advantages of simple chemical structure, easy to synthesize and low price of products. The effects of sub-lethal insecticides on insect chemical communication system and the differences of pheromone communication systems between the resistant and susceptible strain of H. armigera will also be discussed.

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A study on chemical hazard communication for workers exposed to N, N-dimethylformamide (N, N-dimethylformamide 취급근로자의 유해위험 정보 인식도 조사)

  • Yang, Jeong Sun;Lim, Cheol Hong;Lee, Hae Jin
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.21 no.2
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    • pp.103-109
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    • 2011
  • Object: we investigated some factors which can affect workers' comprehension of chemical hazard information and their actions to protect themselves from the hazard. Method: Comprehension score of chemical hazard information and the rate of wearing personal protective equipment (PPE) was surveyed for the 109 workers from 15 factories who were exposed to N, N-dimethylformamide. Difference of the worker's comprehension score of hazard information was analyzed by education interval, work duration and the way of occupational safety and health management between self-managed or sub-contracted. Result: Mean comprehension score of N, N-dimethylformamide hazard, which was given as a short quiz composed of 10 "true" or "false" problems, was 65%. Mean percentage of wearing PPE was improved as the education program was done within a month but decreased after 6 months. Eighty seven % of workers got the chemical hazard information from the material safety data sheet placed at workplace. Conclusion: Education interval and comprehension score affected the rate of wearing PPE. The way of occupational safety and health management self-managed or sub-contracted did not affect the workers' comprehension score on hazard information nor the rate of wearing PPE.

Electron-Beam Mediated Rearrangement and Fragmentation of Bis(diphenylphosphino)alkane Derivatives in Gas Phase

  • Jeon, Yea-Sel;Choi, Jeong Chul;Jeong, Young-Sik;Hwang, Kwang-Jin
    • Rapid Communication in Photoscience
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    • v.2 no.1
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    • pp.31-33
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    • 2013
  • The irradiation of electron-beam onto bis-(diphenylphosphino)methane, ethane, propane and butane initiated phenyl-shift from a phosphine to another phosphine atom and subsequent fragmentation resulted in the formation of triphenylphosphine derivative as key intermediate. The mechanism of those processes is speculated.

Insect Communication: Concepts, Channels and Contexts (곤충의 의사소통: 개념, 채널 및 상황)

  • Jang, Yi-Kweon
    • Korean journal of applied entomology
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    • v.50 no.4
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    • pp.383-393
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    • 2011
  • Because communication facilitates behaviors that are critical for survival and reproduction, it is central to the study of behavior and evolution. One of the most important and difficult issues with respect to communication has been the definition of communication itself. Broadly, it can be defined as an exchange of information from a signaler to a receiver. However, evolution of a signal is likely possible only under conditions in which both the signaler and receiver increase fitness from the exchange of information, often referred to as "true communication." The three primary sensory channels of communication used by animals are chemical, visual, and acoustic. Chemical signals are the oldest and most widespread method of communication. Visual and acoustic signals convey a great deal of information due to ease of modulation, flexibility of signal production, and fast transmission. The most widespread contexts in which animals communicate are sexual interaction and conflict resolution. Signals used for sexual interaction typically contain information about species identity and sexual attractiveness, whereas signals used for conflict resolution may contain information about resource holding potential. Other contexts under which animals communicate include territorial defense, parent-offspring interactions, social integration, sharing of environmental information, and auto-communication.