Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Linear Approximations

Linear Approximations

For a differentiable function of two variables, linear approximation estimates values near a known point by replacing the curved surface with its tangent plane. Consider the function\begin{equation*}f(x,y)=x^2+3y^2\end{equation*}near the point (2, 1). The exact value at this point is f(2, 1) = 22 + 3(1)2 = 4 + 3 = 7.The linear approximation of f(x, y)) near (a, b) is\begin{equation*}L(x,y)=f(a,b)+f_x(a,b)(x-a)+f_y(a,b)(y-b)\end{equation*}First, compute the partial derivatives: fx(x, y) = 2x and...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Indoor Particle's Pollution in Bucharest, Romania.

Toxics·2022

Same author

Survey and Measurements of Indoor Environmental Quality in Urban/Rural Schools Located in Romania.

International journal of environmental research and public health·2022

Same author

Research on Best Solution for Improving Indoor Air Quality and Reducing Energy Consumption in a High-Risk Radon Dwelling from Romania.

International journal of environmental research and public health·2021

See all related articles

Search research articles

Related Experiment Video

Updated: Jul 10, 2026

Implementation of Portable Emissions Measurement Systems PEMS for the Real-driving Emissions RDE Regulation in Europe

Implementation of Portable Emissions Measurement Systems PEMS for the Real-driving Emissions RDE Regulation in Europe

Published on: December 4, 2016

Outdoor Pollution Comparison Between Bucharest and Its Outskirts Using Mobile Laboratory.

Razvan Stefan Popescu¹, Lelia Letitia Popescu¹, Tiberiu Catalina^1,2

¹Buildings' Services Faculty, Technical University of Civil Engineering of Bucharest, 020396 Bucharest, Romania.

International Journal of Environmental Research and Public Health

|January 8, 2025

Summary

Transportation significantly pollutes Bucharest

Keywords:

BTEX PM10 PM2.5 mobile laboratory outdoor pollution

More Related Videos

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx

Published on: December 20, 2016

Visualizing Field Data Collection Procedures of Exposure and Biomarker Assessments for the Household Air Pollution Intervention Network Trial in India

Visualizing Field Data Collection Procedures of Exposure and Biomarker Assessments for the Household Air Pollution Intervention Network Trial in India

Published on: December 23, 2022

Related Experiment Videos

Last Updated: Jul 10, 2026

Implementation of Portable Emissions Measurement Systems PEMS for the Real-driving Emissions RDE Regulation in Europe

Implementation of Portable Emissions Measurement Systems PEMS for the Real-driving Emissions RDE Regulation in Europe

Published on: December 4, 2016

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx

Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx

Published on: December 20, 2016

Visualizing Field Data Collection Procedures of Exposure and Biomarker Assessments for the Household Air Pollution Intervention Network Trial in India

Visualizing Field Data Collection Procedures of Exposure and Biomarker Assessments for the Household Air Pollution Intervention Network Trial in India

Published on: December 23, 2022

Area of Science:

Environmental Science
Atmospheric Chemistry
Public Health

Background:

Outdoor air quality is crucial for public health, especially in urban areas.
Transportation is a major contributor to air pollution in cities.
Understanding the impact of weather on pollutant dispersal is vital.

Purpose of the Study:

To monitor outdoor air quality in Bucharest, Romania, using a mobile laboratory.
To identify key pollutants associated with transportation.
To assess the influence of meteorological variables on pollution levels.

Main Methods:

Utilized a modern mobile laboratory for air quality monitoring.
Measured particulate matter (PM2.5, PM10), CO, O3, SO2, NOx, and BTEX.
Recorded meteorological data including wind, temperature, humidity, and solar radiation.
Compared pollution levels at an urban Bucharest site and a rural Snagov site.

Main Results:

Urban areas exhibited significantly higher pollution levels than rural sites.
Transportation was identified as the primary pollution source in Bucharest.
High concentrations of particulate matter and benzene were detected in the city.
Rainy weather reduced pollutant levels due to washout, while sunny weather increased deposition.

Conclusions:

Continuous air quality monitoring in urban environments is essential.
Targeted pollution control measures are needed to protect public health.
Weather significantly influences air pollutant concentrations and dispersal.