Reducing the Influence of Environmental Factors on Performance of a Diffusion-Based Personal Exposure Kit

Sensor technology has enabled the development of portable low-cost monitoring kits that might supplement many applications in conventional monitoring stations. Despite the sensitivity of electrochemical gas sensors to environmental change, they are increasingly important in monitoring polluted microenvironments. The performance of a compact diffusion-based Personal Exposure Kit (PEK) was assessed for real-time gaseous pollutant measurement (CO, O3, and NO2) under typical environmental conditions encountered in the subtropical city of Hong Kong. A dynamic baseline tracking method and a range of calibration protocols to address system performance were explored under practical scenarios to assess the performance of the PEK in reducing the impact of rapid changes in the ambient environment in personal exposure assessment applications. The results show that the accuracy and stability of the ppb level gas measurement is enhanced even in heterogeneous environments, thus avoiding the need for data post-processing with mathematical algorithms, such as multi-linear regression. This establishes the potential for use in personal exposure monitoring, which has been difficult in the past, and for reporting more accurate and reliable data in real-time to support personal exposure assessment and portable air quality monitoring applications.

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An IoT-based scheme for real time indoor personal exposure assessment

2016 13th IEEE Annual Consumer Communications & Networking Conference (CCNC) ◽

10.1109/ccnc.2016.7444799 ◽

2016 ◽

Cited By ~ 4

Author(s):

Houssem Eddine Fathallah ◽

Vincent Lecuire ◽

Eric Rondeau ◽

Stephane Le Calve

Keyword(s):

Exposure Assessment ◽

Real Time ◽

Personal Exposure ◽

Personal Exposure Assessment

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RESPIRABLE DUST DOSIMETER (RDD) FOR PERSONAL DUST EXPOSURE ASSESSMENT-A LABORATORY INVESTIGATION

Clean Air Journal ◽

10.17159/caj/2005/14/1.7156 ◽

2005 ◽

Vol 14 (1) ◽

Author(s):

B.K Belle

Keyword(s):

Exposure Assessment ◽

Real Time ◽

Screening Tool ◽

Personal Exposure ◽

Underground Mines ◽

Respirable Dust ◽

Dust Exposure ◽

Personal Sampling ◽

Personal Exposure Assessment ◽

Promising Development

The search for an improved or alternative instrument that will be able to measure occupational exposure more accurately and more reliably is continuing. Several developments have been taken place overseas with regard to real-time monitoring instruments for personal exposure assessment. In the light of these developments, the respirable dust dosimeter (RDD) described by Volkwein et al. (2000) appeared to be a promising development. RDD measures the dust exposure in differential pressure units (mm of Hg) indicating that it is a surrogate for the mass of dust on a gravimetric filter. This paper describes the results of an evaluation on theRDDunder laboratory conditions before evaluating them in underground mines for personal dust exposure assessment.The laboratory study has shown that there is a potential for the RDD sampler as a screening tool for engineering sample purposes. However, RDD was comparatively expensive during the research exercise costing approximately 16UK Pounds per RDD tube. Further, there was no well-accepted procedure on collect dust samples using RDD tube for further quartz analysis. Finally, due to its reasonable estimates of real-time cumulative shift dust exposure, and its small lightweight package, the RDD was further recommended for personal sampling purposes in the SouthAfrican mines.

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Personal exposure assessment of pesticides in residents: the association between hand wipes and urinary biomarkers

Environmental Research ◽

10.1016/j.envres.2021.111282 ◽

2021 ◽

pp. 111282

Author(s):

A. Oerlemans ◽

D.M. Figueiredo ◽

J.G.J. Mol ◽

R. Nijssen ◽

R.B.M. Anzion ◽

...

Keyword(s):

Exposure Assessment ◽

Personal Exposure ◽

Urinary Biomarkers ◽

Personal Exposure Assessment

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Real-time and near real-time ZTD from a local network of low-cost dual-frequency GNSS receivers.

10.5194/egusphere-egu21-5465 ◽

2021 ◽

Author(s):

Tomasz Hadas ◽

Grzegorz Marut ◽

Jan Kapłon ◽

Witold Rohm

Keyword(s):

Water Vapor ◽

Real Time ◽

Low Cost ◽

Weather Prediction ◽

Local Network ◽

System Component ◽

Dual Frequency ◽

Lower Accuracy ◽

Gnss Receivers ◽

The Impact

The dynamics of water vapor distribution in the troposphere, measured with Global Navigation Satellite Systems (GNSS), is a subject of weather research and climate studies. With GNSS, remote sensing of the troposphere in Europe is performed continuously and operationally under the E-GVAP (http://egvap.dmi.dk/) program with more than 2000 permanent stations. These data are one of the assimilation system component of mesoscale weather prediction models (10 km scale) for many nations across Europe. However, advancing precise local forecasts for severe weather requires high resolution models and observing system.&#160; &#160;Further densification of the tracking network, e.g. in urban or mountain areas, will be costly when considering geodetic-grade equipment. However, the rapid development of GNSS-based applications results in a dynamic release of mass-market GNSS receivers. It has been demonstrated that post-processing of GPS-data from a dual-frequency low-cost receiver allows retrieving ZTD with high accuracy. Although low-cost receivers are a promising solution to the problem of densifying GNSS networks for water vapor monitoring, there are still some technological limitations and they require further development and calibration.We have developed a low-cost GNSS station, dedicated to real-time GNSS meteorology, which provides GPS, GLONASS and Galileo dual-frequency observations either in RINEX v3.04 format or via RTCM v3.3 stream, with either Ethernet or GSM data transmission. The first two units are deployed in a close vicinity of permanent station WROC, which belongs to the International GNSS Service (IGS) network. Therefore, we compare results from real-time and near real-time processing of GNSS observations from a low-cost unit with IGS Final products. We also investigate the impact of replacing a standard patch antenna with an inexpensive survey-grade antenna. Finally, we deploy a local network of low-cost receivers in and around the city of Wroclaw, Poland, in order to analyze the dynamics of troposphere delay at a very high spatial resolution.As a measure of accuracy, we use the standard deviation of ZTD differences between estimated ZTD and IGS Final product. For the near real-time mode, that accuracy is 5&#160;mm and 6 mm, for single- (L1) and dual-frequency (L1/L5,E5b) solution, respectively. Lower accuracy of the dual-frequency relative solution we justify by the missing antenna phase center correction model for L5 and E5b frequencies. With the real-time Precise Point Positioning technique, we estimate ZTD with the accuracy of 7.5 &#8211; 8.6 mm. After antenna replacement, the accuracy is improved almost by a factor of 2 (to 4.1 mm), which is close to the 3.1&#160;mm accuracy which we obtain in real-time using data from the WROC station.

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A network of low-cost temperature sensors for real-time monitoring of combined sewer overflow

10.5194/egusphere-egu21-16386 ◽

2021 ◽

Author(s):

Mathias Riechel ◽

Oriol Gutierrez ◽

Silvia Busquets ◽

Neus Amela ◽

Valentina Dimova ◽

...

Keyword(s):

Real Time ◽

Low Cost ◽

Temperature Sensors ◽

Sensor Technology ◽

Detection Accuracy ◽

Combined Sewer Overflow ◽

Monitoring Equipment ◽

Flow Monitoring ◽

Combined Sewer ◽

Sewer Overflow

The H2020 innovation project digital-water.city (DWC) aims at boosting the integrated management of water systems in five major European cities &#8211;&#160;Berlin, Copenhagen, Milan, Paris and Sofia&#160;&#8211; by leveraging the potential of data and digital technologies. The goal is to quantify the benefits of a panel of 15 innovative digital solutions and achieve their long-term uptake and successful integration in the existing digital systems and governance processes. One of these promising technologies is a new generation of sensors for measuring combined sewer overflow occurrence, developed by ICRA and IoTsens.Recent EU regulations have correctly identified CSOs as an important source of contamination and promote appropriate monitoring of all CSO structures in order to control and avoid the detrimental effects on receiving waters. Traditionally there has been a lack of reliable data on the occurrence of CSOs, with the main limitations being: i) the high number of CSO structures per municipality or catchment and ii) the high cost of the flow-monitoring equipment available on the market to measure CSO events. These two factors and the technical constraints of accessing and installing monitoring equipment in some CSO structures have delayed the implementation of extensive monitoring of CSOs. As a result, utilities lack information about the behaviour of the network and potential impacts on the local water bodies.The new sensor technology developed by ICRA and IoTsens provides a simple yet robust method for CSO detection based on the deployment of a network of innovative low-cost temperature sensors. The technology reduces CAPEX and OPEX for CSO monitoring, compared to classical flow or water level measurements, and allows utilities to monitor their network extensively. The sensors are installed at the overflows crest and measure air temperature during dry-weather conditions and water temperature when the overflow crest is submerged in case of a CSO event. A CSO event and its duration can be detected by a shift in observed temperature, thanks to the temperature difference between the air and the water phase. Artificial intelligence algorithms further help to convert the continuous measurements into binary information on CSO occurrence. The sensors can quantify the CSO occurrence and duration and remotely provide real-time overflow information through LoRaWAN/2G communication protocols.The solution is being deployed since October 2020 in the cities of Sofia, Bulgaria, and Berlin, Germany, with 10 offline sensors installed in each city to improve knowledge on CSO emissions. Further 36 (Sofia) and 9 (Berlin) online sensors will follow this winter. Besides its main goal of improving knowledge on CSO emissions, data in Sofia will also be used to identify suspected dry-weather overflows due to blockages. In Berlin, data will be used to improve the accuracy of an existing hydrodynamic sewer model for resilience analysis, flood forecasting and efficient investment in stormwater management measures. First results show a good detection accuracy of CSO events with the offline version of the technology. As measurements are ongoing and further sensors will be added, an enhanced set of results will be presented at the conference.Visit us: https://www.digital-water.city/&#160;Follow us: Twitter (@digitalwater_eu); LinkedIn (digital-water.city)

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Service Discovery Framework for Distributed Embedded Real-Time Systems

Advances in Systems Analysis, Software Engineering, and High Performance Computing - Handbook of Research on Emerging Advancements and Technologies in Software Engineering ◽

10.4018/978-1-4666-6026-7.ch007 ◽

2014 ◽

pp. 126-147 ◽

Cited By ~ 1

Author(s):

Furkh Zeshan ◽

Radziah Mohamad ◽

Mohammad Nazir Ahmad

Keyword(s):

Web Services ◽

Real Time ◽

Context Awareness ◽

Service Discovery ◽

Low Cost ◽

High Volume ◽

Heterogeneous Environments ◽

Real Time Systems ◽

Loosely Coupled ◽

Time Systems

Embedded systems are supporting the trend of moving away from centralised, high-cost products towards low-cost and high-volume products; yet, the non-functional constraints and the device heterogeneity can lead to system complexity. In this regard, Service-Oriented Architecture (SOA) is the best methodology for developing a loosely coupled, dynamic, flexible, distributed, and cost-effective application. SOA relies heavily on services, and the Semantic Web, as the advanced form of the Web, handles the application complexity and heterogeneity with the help of ontology. With an ever-increasing number of similar Web services in UDDI, a functional description of Web services is not sufficient for the discovery process. It is also difficult to rank the similar services based on their functionality. Therefore, the Quality of Service (QoS) description of Web services plays an important role in ranking services within many similar functional services. Context-awareness has been widely studied in embedded and real-time systems and can also play an important role in service ranking as an additional set of criteria. In addition, it can enhance human-computer interaction with the help of ontologies in distributed and heterogeneous environments. In order to address the issues involved in ranking similar services based on the QoS and context-awareness, the authors propose a service discovery framework for distributed embedded real-time systems in this chapter. The proposed framework considers user priorities, QoS, and the context-awareness to enable the user to select the best service among many functional similar services.

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Effects of Individual and Environmental Factors on GPS-Based Time Allocation in Urban Microenvironments Using GIS

Applied Sciences ◽

10.3390/app8102007 ◽

2018 ◽

Vol 8 (10) ◽

pp. 2007 ◽

Cited By ~ 2

Author(s):

Audrius Dėdelė ◽

Auksė Miškinytė ◽

Irma Česnakaitė ◽

Regina Gražulevičienė

Keyword(s):

Environmental Factors ◽

Exposure Assessment ◽

Time Allocation ◽

Activity Patterns ◽

Personal Exposure ◽

Health Impact ◽

Individual Characteristics ◽

Time Activity ◽

Study Results ◽

The Impact

Time-activity patterns are an essential part of personal exposure assessment to various environmental factors. People move through different environments during the day and they have different daily activity patterns which are significantly influenced by individual characteristics and the residential environment. In this study, time spent in different microenvironments (MEs) were assessed for 125 participants for 7 consecutive days to evaluate the impact of individual characteristics on time-activity patterns in Kaunas, Lithuania. The data were collected with personal questionnaires and diaries. The global positioning system (GPS) sensor integrated into a smartphone was used to track daily movements and to assess time-activity patterns. The study results showed that behavioral and residential greenness have a statistically significant impact on time spent indoors. These results underline the high influence of the individual characteristics and environmental factors on time spent indoors, which is an important determinant for exposure assessment and health impact assessment studies.

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