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The Experts below are selected from a list of 276 Experts worldwide ranked by ideXlab platform
Liu Jun – One of the best experts on this subject based on the ideXlab platform.
Environmental Monitoring in China, 2009Co-Authors: Liu JunAbstract:
How to audit a huge number of data which are produced by regional Air Monitoring network is a big trouble.Here we take PRD network for example to present the data audit method of regional Air Monitoring network.
Zhang Zhen-tian – One of the best experts on this subject based on the ideXlab platform.
Environmental Monitoring in China, 2005Co-Authors: Zhang Zhen-tianAbstract:
According to the regional Air quality management development situation,this paper presents the thought and content of automatic regional Air Monitoring network construction,and explores the strategy and solution of establishing a regional Air Monitoring QA/QC technical system.
Kenneth E. Noll – One of the best experts on this subject based on the ideXlab platform.
Atmospheric Environment, 2003Co-Authors: Kenneth E. Noll, Satoru MitsutomiAbstract:
Abstract An Air Monitoring site selection procedure has been developed that ranks potential Air Monitoring sites according to their ability to represent the ambient dosage (i.e. the product of the concentration by exposure time) pattern in a Monitoring network. The Dosage Monitoring Survey Design (DMSS) analyzes the dosage impact at grid receptors by dispersion modeling. High-dosage grids become potential Monitoring sites. The uniqueness of DMSS is the introduction of a cluster of contiguous grid receptors that exceed a threshold value. One station is assigned to the cluster, thus eliminating redundancies among adjacent high dosage grids. The site selection procedure specifies locations for high-dosage Monitoring stations along with the cluster area capabilities of each station. An efficiency term based on the ratio of a station’s dosage measuring capabilities to the total dosage in the network provides a method of ranking stations. An analysis of the design procedure shows that as the threshold concentration decreased the distance from the source where the maximum dosage was found increased and there was a slight increase in station efficiency. Also, as averaging time increased, higher efficiencies were achieved for individual stations.
Atmospheric Environment, 2003Co-Authors: Kenneth E. Noll, Terry L. Miller, Jay E. Norco, R.k. RauferAbstract:
Abstract Quantitative methods for determining the total number and location of Air Monitoring sites to meet specific Air sampling objectives have proven difficult to identify by the traditional application of diffusion models and historical meteorological data. Objective criteria for site selection are important to the design of cost-effective Air Monitoring surveys, obtaining required data results in the minimum time period, and trade-off decisions between fixed and mobile Monitoring options. The objective technique reported here utilizes statistical methods to determine the number and location of sensors from the ratio of areas defined by 1. (1) the range of available historical meteorological conditions producing maximum concentrations and 2. (2) a predetermined concentration measurement tolerance range around the maximum concentration which represents the maximum within 10 or 20% of the predicted value. The desired confidence level for measuring a specified Air pollution maximum value is also required. The application of the method to the design of an Air Monitoring network to support an intermittent control system for two power plants in central Illinois confirms the practicality of the method. The final Monitoring network resulted from a consideration of numerous combinations of fixed and mobile Monitoring options. The sites having the highest probability of occurrence and the greatest predicted concentrations were selected for fixed, continuous Monitoring. Where high concentrations occur with a relatively low frequency, a mobile monitor which relies on meteorological forecasting can be dispatched through a control center to predetermined, fixed, sites is cost-effective in reducing the requirement for a large number of permanent monitors.
Elizabeth Woolfenden – One of the best experts on this subject based on the ideXlab platform.
sorbent based sampling methods for volatile and semi volatile organic compounds in Air part 1 sorbent based Air Monitoring optionsJournal of Chromatography A, 2010Co-Authors: Elizabeth WoolfendenAbstract:
Sorbent tubes/traps are widely used in combination with gas chromatographic (GC) analytical methods to monitor the vapour-phase fraction of organic compounds in Air. Target compounds range in volatility from acetylene and freons to phthalates and PCBs and include apolar, polar and reactive species. Airborne vapour concentrations will vary depending on the nature of the location, nearby pollution sources, weather conditions, etc. Levels can range from low percent concentrations in stack and vent emissions to low part per trillion (ppt) levels in ultra-clean outdoor locations. Hundreds, even thousands of different compounds may be present in any given atmosphere. GC is commonly used in combination with mass spectrometry (MS) detection especially for environmental Monitoring or for screening uncharacterised workplace atmospheres. Given the complexity and variability of organic vapours in Air, no one sampling approach suits every Monitoring scenario. A variety of different sampling strategies and sorbent media have been developed to address specific applications. Key sorbent-based examples include: active (pumped) sampling onto tubes packed with one or more sorbents held at ambient temperature; diffusive (passive) sampling onto sorbent tubes/cartridges; on-line sampling of Air/gas streams into cooled sorbent traps; and transfer of Air samples from containers (canisters, Tedlar® bags, etc.) into cooled sorbent focusing traps. Whichever sampling approach is selected, subsequent analysis almost always involves either solvent extraction or thermal desodesorption (TD) prior to GC(/MS) analysis. The overall performance of the Air Monitoring method will depend heavily on appropriate selection of key sampling and analytical parameters. This comprehensive review of Air Monitoring using sorbent tubes/traps is divided into 2 parts. (1) Sorbent-based Air sampling option. (2) Sorbent selection and other aspects of optimizing sorbent-based Air Monitoring methods. The paper presents current state-of-the-art and recent developments in relevant areas such as sorbent research, sampler design, enhanced approaches to analytical quality assurance and on-tube derivatisation.
Yukio Yanagisawa – One of the best experts on this subject based on the ideXlab platform.
International Journal of Environmental Research and Public Health, 2015Co-Authors: Shintaro Shirato, Atsushi Iizuka, Atsushi Mizukoshi, Miyuki Noguchi, Akihiro Yamasaki, Yukio YanagisawaAbstract:
Continuous ambient Air Monitoring systems have been introduced worldwide. However, such Monitoring forces autonomous communities to bear a significant financial burden. Thus, it is important to identify pollutant-Monitoring stations that are less efficient, while minimizing loss of data quality and mitigating effects on the determination of spatiotemporal trends of pollutants. This study describes a procedure for optimizing a constant ambient Air Monitoring system in the Kanto region of Japan. Constant ambient Air Monitoring stations in the area were topologically classified into four groups by cluster analysis and principle component analysis. Then, Air pollution characteristics in each area were reviewed using concentration contour maps and average pollution concentrations. We then introduced three simple criteria to reduce the number of Monitoring stations: (1) retain the Monitoring station if there were similarities between its data and average data of the group to which it belongs; (2) retain the station if its data showed higher concentrations; and (3) retain the station if the monitored concentration levels had an increasing trend. With this procedure, the total number of Air Monitoring stations in suburban and urban areas was reduced by 36.5%. The introduction of three new types of Monitoring stations is proposed, namely, mobile, for local non-methane hydrocarbon pollution, and Ox-prioritized.
International Journal of Environmental Research and Public Health, 2014Co-Authors: Atsushi Iizuka, Shintaro Shirato, Atsushi Mizukoshi, Miyuki Noguchi, Akihiro Yamasaki, Yukio YanagisawaAbstract:
This study demonstrates an application of cluster analysis to constant ambient Air Monitoring data of four pollutants in the Kanto region: NOx, photochemical oxidant (Ox), suspended particulate matter, and non-methane hydrocarbons. Constant ambient Air Monitoring can provide important information about the surrounding atmospheric pollution. However, at the same time, ambient Air Monitoring can place a significant financial burden on some autonomous communities. Thus, it has been necessary to reduce both the number of Monitoring stations and the number of chemicals monitored. To achieve this, it is necessary to identify those Monitoring stations and pollutants that are least significant, while minimizing the loss of data quality and mitigating the effects on the determination of any spatial and temporal trends of the pollutants. Through employing cluster analysis, it was established that the ambient Monitoring stations in the Kanto region could be clustered topologically for NOx and Ox into eight groups. From the results of this analysis, it was possible to identify the similarities in site characteristics and pollutant behaviors.