Water Classification, Safety, and Quality Assessment
1. Classification of Water by Use and Origin
Hygienic Perspective
Origin:
- Rain (atmospheric) water
- Surface water (running, flowing, stagnant)
- Ocean water
- Underground water – formed from atmospheric or surface water
Rain Water:
- Source of all freshwater in the world
- May be collected directly from roofs and other prepared collection systems and stored in cisterns for later use
- Quality is reasonable but it may be contaminated by gases and particles (e.g., SO2 or NO2) that are washed out of the atmosphere or
Evaluating and Developing Theories in Information Systems
Volume 13, Issue 1, pp. 1-30, January 2012
Evaluating and Developing Theories in the Information Systems Discipline
* Cynthia Beath was the accepting senior editor. This article was submitted on 3rd March 2011 and went through two revisions.
2
Evaluating and Developing Theories in the Information Systems Discipline
Journal of the Association for Information Systems Vol. 13 Issue 1 pp. 1-30 January 2012
Nothing is as practical as a good theory (Lewin, 1945, p. 129).
1. Introduction
For many researchers,
Read MoreEvaluating and Developing Theories in Information Systems
Volume 13, Issue 1, pp. 1-30, January 2012
Evaluating and Developing Theories in the Information Systems Discipline
* Cynthia Beath was the accepting senior editor. This article was submitted on 3rd March 2011 and went through two revisions.
2
Evaluating and Developing Theories in the Information Systems Discipline
Journal of the Association for Information Systems Vol. 13 Issue 1 pp. 1-30 January 2012
Nothing is as practical as a good theory (Lewin, 1945, p. 129).
1. Introduction
For many researchers,
Read MoreEvaluating and Developing Theories in the Information Systems Discipline: A Framework and Criteria
Volume 13, Issue 1, pp. 1-30, January 2012
Evaluating and Developing Theories in the Information Systems Discipline
* Cynthia Beath was the accepting senior editor. This article was submitted on 3rd March 2011 and went through two revisions.
2
Evaluating and Developing Theories in the Information Systems Discipline
Journal of the Association for Information Systems Vol. 13 Issue 1 pp. 1-30 January 2012
Nothing is as practical as a good theory (Lewin, 1945, p. 129).
1. Introduction
For many researchers,
Read MorePrinciples of Physiologically Adequate Lighting & Measurement
Principles of Physiologically Adequate Lighting & Measurement
Visible Light
Visible light spectrum: 500/600-700/800 nm
Types of Inadequate Lighting
Insufficient Light
Not enough light for the visual task.
Glare
Too much light for the need. Occurs when a bright light source or reflection interferes with object visibility.
Causes of Reflected Glare:
- Light reflected from polished, shiny, or glossy surfaces
- Glass on picture frames or windows at night
- Monitors/screens
Causes of Direct Glare:
- Very bright light
Introduction to Geographic Information Systems (GIS)
Fundamental Concepts in GIS
a. Characterizing Geographic Concepts
In the discrete object view, the world is seen as empty except where occupied by objects with well-defined boundaries. Examples include lakes in Minnesota or mountains in Scotland.
In the continuous field view, the world is described by variables measurable at any point on Earth’s surface, with values changing across the surface.
b. Digital Representation
Discrete objects are represented using vector data, while continuous fields are represented
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