ESTIMATION OF GPS DISPERSIVE AND NON-DISPERSIVE NETWORK CORRECTION FOR ISKANDARnet NETWORK-BASED REAL-TIME KINEMATIC (N-RTK) POSITIONING SYSTEM

The concept of N-RTK positioning has been extensively developed in order to better model the distance-dependent errors of GPS carrier-phase measurements. These errors can be separated into a frequency-dependent or dispersive component (i.e., the ionospheric delay) and a non-dispersive component (i.e., the tropospheric delay and orbit biases) to express the network correction in order to attain better modelling of GPS distance dependent errors. However, the N-RTK performance may degrades due to severe atmospheric irregularities that would seriously affect the modelling of the GPS distance-dependent errors, thus affecting the quality of network correction generation. The development of integrity monitoring for network correction would be great idea to identify the quality and reliability of network correction data dissemination. Therefore, this paper aims to estimates the trend of GPS dispersive and non-dispersive network correction to supports future development of integrity monitoring for network correction of ISKANDARnet N-RTK positioning system. The first part of this paper is to extract the GPS dispersive and non-dispersive network residual components. This part includes the double-differencing technique, ambiguity resolution and carrier-phased linear combination in the process. The LIM then are applied for user network coefficient value computation purpose in the second part. Finally, the GPS dispersive and non-dispersive network correction can be generated with GF and IF network correction algorithm respectively. The trend of GPS dispersive and non-dispersive network correction is expected to aid the estimation and realization of threshold limit value for development of integrity monitoring for network correction of ISKANDARnet N-RTK positioning system.

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EXPERIMENTAL SUBSTANTIATION OF THE MAXIMUM ALLOWABLE CONCENTRATION OF DIOCTYL TEREPHTHALATE IN THE AIR OF THE WORKING AREA

Токсикологический вестник ◽

10.36946/0869-7922-2020-1-34-38 ◽

2020 ◽

pp. 34-38

Author(s):

A. S. Radilov ◽

S. A. Solntseva ◽

I. E. Shkaeva ◽

S. A. Dulov ◽

E. V. Vivulanets ◽

...

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Functional State ◽

Hematological Parameters ◽

Inhalation Exposure ◽

Threshold Limit Value ◽

Maximum Allowable Concentration ◽

Limit Value ◽

Threshold Limit ◽

The Central Nervous System

Toxicity and hazard assessment of dioctyl terephthalate (DOTP) was performed in acute, subacute, and chronic experiments, and its principal toxicometry parameters were determined.It was found that on single exposure DOTP exhibits low toxicity and hazard. No resorptive and irritant effects on skin and mucous membrane of eyes were detected in animal experiments. The single inhalation exposure threshold limit value was set at 300 mg/m3, based on the results of monitoring of the functional state of the central nervous system and myocardium and hematological parameters.Thirty-day subacute experiments (oral administration, inhalation exposure, and skin applications) revealed no accumulation of the compound.Four-month chronic exposure to DOTP aerosols (concentration 96,8 mg/m3) caused disorder of the functional state of the central nervous system and myocardium, changes in the hematological and biochemical parameters, gas and acid-base status of the blood, and morphological changes in the lungs and heart. Embryotoxic, genotoxic and gonadotoxic effects were not detected.The chronic inhalation exposure threshold limit value for DOTP (Limch) was set at 18,6 mg/m3, and the concentration of 3,4 mg/m3 was found to be ineffective.The maximum allowable concentration of DOTP in the air of the working area was set at 3,0 mg/m3, hazard class 3.

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Threshold Limit Value

Encyclopedic Dictionary of Polymers ◽

10.1007/978-1-4419-6247-8_11862 ◽

2011 ◽

pp. 749-749

Author(s):

Jan W. Gooch

Keyword(s):

Threshold Limit Value ◽

Limit Value ◽

Threshold Limit

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Should the Threshold Limit Value for Power Frequency (60 Hz) Magnetic Fields be Changed? Perceptions Among Scientists and Other Risk Experts

AIHA Journal ◽

10.1080/15428110208984750 ◽

2002 ◽

Vol 63 (5) ◽

pp. 636-640

Author(s):

Shari McMahan ◽

Rafer Lutz ◽

Jon'a Meyer

Keyword(s):

Magnetic Fields ◽

Threshold Limit Value ◽

Limit Value ◽

Threshold Limit ◽

Power Frequency

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Global positioning system resurvey of Southern California Seismic Network stations

Bulletin of the Seismological Society of America ◽

10.1785/bssa0850010361 ◽

1995 ◽

Vol 85 (1) ◽

pp. 361-374

Author(s):

Jennifer S. Haase ◽

Egill Hauksson ◽

Hiroo Kanamori ◽

Jim Mori

Keyword(s):

Global Positioning System ◽

Southern California ◽

Seismic Station ◽

Seismic Network ◽

Positioning System ◽

Dual Frequency ◽

Time Data ◽

Phase Measurements ◽

Station Coordinates ◽

Global Positioning

Abstract Systematic errors in travel-time data from local earthquakes can sometimes be traced to inaccuracies in the published seismic station coordinates. This prompted a resurvey of the stations of the Caltech/USGS Southern California Seismic Network (SCSN) using the Global Positioning System (GPS). We surveyed 241 stations of the SCSN using Trimble and Ashtech dual-frequency GPS receivers and calculated positions accurate to 3 m using differential positioning from carrier phase measurements. Twelve percent of the stations that were surveyed were found to be mislocated by more than 500 m. Stations of the TERRAscope and USC networks were also surveyed, as well as a network of portable seismic stations deployed shortly after the 1992 Joshua Tree and Landers earthquakes. The new coordinates and the offsets from the old coordinates are given below. The new coordinates are being used in SCSN locations as of 1 January 1994.

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The Physical and Chemical Air Quality, Worker’s Characteristics, and Respiratory Symptoms Among Printing Workers in Surabaya

JURNAL KESEHATAN LINGKUNGAN ◽

10.20473/jkl.v8i2.2016.195-205 ◽

2016 ◽

Vol 8 (2) ◽

pp. 195

Author(s):

Devi Anggar Oktaviani ◽

Corie Indria Prasasti

Keyword(s):

Air Quality ◽

Respiratory Symptoms ◽

Threshold Limit Value ◽

Dust Collector ◽

Printing Industry ◽

Cross Sectional ◽

Administrative Control ◽

Limit Value ◽

Control Application ◽

Physical And Chemical

Abstract: Printing industry is an industry which in its production process generate air pollutants such as Particulate Matter (PM). The exceeds limit of PM2,5 can cause respiratory symptoms, cardiovascular disease, and pulmonary function disorder. The objective of this study was to analyze physical and chemical air quality and respiratory symptoms among printing industry workers in Surabaya. It was observational study with cross sectional approach and analyzed descriptively. The physical and chemical air quality was measured by Thermohygrometer and Haz Dust EPAM 5000 at three different areas in production unit. Worker’s characteristics and respiratory symptoms were obtained from 20 respondent’s questionnaires. The highest concentration of PM2,5 level was at cutting room (area 1), which maximum concentration was 20.0 μg/m3 and the average was 6.1 μg/m3. The result showed that PM2,5 levels was below threshold limit value. It is suggested to printing industry to improve administrative control application by managing work period and useing mask, to clean ventilation, dust collector, or production facilities and to examine health status regularly to public health center for workers at printing industry.Keywords: physical and chemical air quality, printing industry, respiratory symptoms

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Analysis The Level Of PM2,5 And Lung Function Of Organic Fertilizer Industry Workers In Nganjuk

JURNAL KESEHATAN LINGKUNGAN ◽

10.20473/jkl.v11i2.2019.141-149 ◽

2019 ◽

Vol 11 (2) ◽

pp. 141

Author(s):

Imfatul Tria Nur Azizah

Keyword(s):

Lung Function ◽

Organic Fertilizer ◽

Threshold Limit Value ◽

Cross Sectional ◽

Fertilizer Industry ◽

Limit Value ◽

Function Impairment ◽

Packing Process ◽

Cross Sectional Design ◽

Lung Function Impairment

Organic fertilizer industry in Nganjuk uses manure as basic materials of production. Its process produced particulate matter 2,5 (PM2,5) in the form of dust and smoke. PM2,5 can be inhaled and be retained until alveoli, so it is potentially caused lung function impairment to the workers. The objective of this research was to analyzed the level of PM2,5 and lung function of organic fertilizer industry workers in Nganjuk. The type of this research was observasional descriptive quantitative with cross sectional design. The research sample was using total population of 10 production workers. The result of this research showed that the level of PM2,5 inhaled which exceeded Threshold Limit Value (TLV) or > 3 mg/m3 were on 2 workers who worked on drying and packing process. The average of PM2,5 environment level which exceeded TLV were on manufacturing of granuls, heating and packing process area. Workers who had lung function impairment were 4 workers (40%). Lung function impairment more likely found in workers with exposure of PM2,5 inhaled≤ 3 mg/m3, has age 41 – 60 years, worked period < 5 years, always using cloth as respiratory protective equipment, and had worked in the other places either direct or indirect exposure of dust. The conclusion of this research is production workers of organic fertilizer industry in Nganjuk has risk of lung function impairment. Suggestions for the owner of organic fertilizer industry in Nganjuk are to install natural and unnatural ventilations and to provide air purifying respirators.

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Metallic Mercury Contamination of the Dental Operatory

Human Factors The Journal of the Human Factors and Ergonomics Society ◽

10.1177/001872087501700405 ◽

1975 ◽

Vol 17 (4) ◽

pp. 346-355 ◽

Cited By ~ 2

Author(s):

Richard G. Domey

Keyword(s):

San Antonio ◽

Threshold Limit Value ◽

Mercury Contamination ◽

Metallic Mercury ◽

General Lack ◽

Limit Value ◽

Threshold Limit ◽

Routine Monitoring ◽

Cleaning Methods

The American Conference of Governmental Industrial Hygienists 1971 standard threshold limit value (TLV) of 0.55 mgHg/m of air was found to be exceeded frequently in a sample of 60 dental operatories in San Antonio, Texas. Significant differences in contamination among laboratories were found, among sites within operatories, and among times of day, correlated with kilograms of mercury used, average number of amalgams inserted per day, age of operatories, height of carpeting pile, cleaning methods, frequency of cleaning, and general lack of routine monitoring and use of bioassays. Recommendations for control of metallic mercury contamination in dental operatories are offered.

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