Dr. SaMeH S. Ahmed

Associate Prof. of Environmental Engineering

Digital density me

Digital density meters


Hydrostatic Pressure-based Instruments: This technology relies upon Pascal's Principle which states that the pressure difference between two points within a vertical column of fluid is dependent upon the vertical distance between the two points, the density of the fluid and the gravitational force. This technology is often used for tank gaging applications as a convenient means of liquid level and density measure.

Vibrating Element Transducers: This type of instrument requires a vibrating element to be placed in contact with the fluid of interest. The resonant frequency of the element is measured and is related to the density of the fluid by a characterization that is dependent upon the design of the element. In modern laboratories precise measurements of specific gravity are made using oscillating U-tube meters. These are capable of measurement to 5 to 6 places beyond the decimal point and are used in the brewing, distilling, pharmaceutical, petroleum and other industries. The instruments measure the actual mass of fluid contained in a fixed volume at temperatures between 0 and 80 °C but as they are microprocessor based can calculate apparent or true specific gravity and contain tables relating these to the strengths of common acids, sugar solutions, etc. The vibrating fork immersion probe is another good example of this technology. This technology also includes many coriolis-type mass flow meters which are widely used in chemical and petroleum industry for high accuracy mass flow measurement and can be configured to also output density information based on the resonant frequency of the vibrating flow tubes.[8]

Ultrasonic Transducer: Ultrasonic waves are passed from a source, through the fluid of interest, and into a detector which measures the acoustic spectroscopy of the waves. Fluid properties such as density and viscosity can be inferred from the spectrum.

Radiation-based Gauge: Radiation is passed from a source, through the fluid of interest, and into a scintillation detector, or counter. As the fluid density increases, the detected radiation "counts" will decrease. The source is typically the radioactive isotope cesium-137, with a half-life of about 30 years. A key advantage for this technology is that the instrument is not required to be in contact with the fluid—typically the source and detector are mounted on the outside of tanks or piping.[9]

Buoyant Force Transducer: the buoyancy force produced by a float in a homogeneous liquid is equal to the weight of the liquid that is displaced by the float. Since buoyancy force is linear with respect to the density of the liquid within which the float is submerged, the measure of the buoyancy force yields a measure of the density of the liquid. One commercially available unit claims the instrument is capable of measuring specific gravity with an accuracy of ± 0.005 SG units. The submersible probe head contains a mathematically characterized spring-float system. When the head is immersed vertically in the liquid, the float moves vertically and the position of the float controls the position of a permanent magnet whose displacement is sensed by a concentric array of Hall-effect linear displacement sensors. The output signals of the sensors are mixed in a dedicated electronics module that provides a single output voltage whose magnitude is a direct linear measure of the quantity to be measured.

The best book

Prayer Times

Click here

Office hours

Sunday:     12-1

Monday:     12-1

Tuesday:     10-12

Wednesday: 10-11

You are welcome to contact me by at any time

You  may also contact me via WhatsApp group, ..

Ext. 2524

Civil Eng. Students

DON'T miss!

Love your department and be proud of your field of study

As we approaching the second midterm exams..  Get ready and remember our offices are open to answer you . do not hesitate to .contact me if you have difficulties

For CE 370 students : I do apologize for did not attend the extra lab session that proposed to be on Wednesday at 6 am.  Sorry

Good Luck


My Dear Students

Please visit the  announcement box for the relevant course and make sure that you can download and upload easily, otherwise

.contact me  to sort it out

There will be an orientation session in the midell of this term to help you select your track in Civil and Environmental Engineering


Special Issue

Electrical Power Resources: Coal versus Renewable Energy

  Published Online on January 2016

Mining Engineering

Mining engineering is an engineering discipline that involves practice, theory, science, technology, and the application of extracting and processing minerals from a naturally occurring environment. Mining engineering also includes processing minerals for additional value.

Environmental Engineering

Environmental engineers are the technical professionals who identify and design solutions for    environmental problems. Environmental engineers provide safe drinking water, treat and properly dispose of wastes, maintain air quality, control water pollution, and remediate sites contaminated due to spills or improper disposal of hazardous substances. They monitor the quality of the air, water, and land. And, they develop new and improved means to protect the environment.


Actions speak louder than words



College of Eng. MU



Universities I've worked in

Assuit University (Home University), Egypt

Imperial College, London, UK

Faculty of Engineering, Al-Mergeb University, Libya

King Saud University, KSA

,Majmaah University

Majmaah University has a very nice web page that provide  all information regarding deanships, colleges, activities,  campuses and many others. Search your request in

Also visit

My Academic Pages


and give me


How many red balls we need to make balance 


Egypt vs Tunisia (Handball final)  30/1/2016

Currency Converter

Click here


Click here

Course 2016/17-1

  1. Computer Applications in Surveying  CE 473
  2. Surveying 1 CE 370
  3. Photogrammetry CE 474
  4. Surveying II  CE 371
  5. Design I  (round 4) CE 498

The Rules of Life

Rule #7


Member of the Editorial Board: " Journal of Water Resources and Ocean Sciences"  2013


Participating in The Third International Conference on Water, Energy and Environment,(ICWEE) 2015 - American University of Sharjah, UAE 24-26 March 2015 with a Paper and Poster

New article

Recovery of Titania from Waste-Sludge of Majmaah Water Treatment Plant

"Production of Titania Nano-particles from Wast-


Coming soon

Results of M2 CE311

Student Conference

Participation  in the 6Th Student Conference

With a paper and oral presentation

From the Senior Design Project CE499 -35

See inside, the paper, and presentation

CE 370 Course

Surveying  I -  CE 370 - 2016-2017-1

Power point


Lecture notes

Second Midterm Exam


Model Answer
Inside, please follow:

Student Performance Records

CE 371 Course

Surveying II - CE 371 - 2016-2017-1


First midterm exam



See Inside

Student Performance Records

CE473 Course

Computer Applications in Surveying

CE 473


Power point


Exams + Quizzes


CE 474 Course

2015-2016-2 - Photogrammetry  CE474

Available 0-1-2-3-4 Power point


Quizzes 2 and 3 with model Answer

Available Chapter 1,2,3,4,5 Lecture notes

Report 1  Cameras Report


60 marks Exams

See Inside

Student Performance Records

CE 360 Course

Environmental Engineering 1

CE 360: Environmental Engineering 1


Y PP0-1-2-3,4 Power point
Y 1,2,3,4,5 Chapters

Water quality Poster + Climate Change Reports
will be announced (Quiz #2 will be using D2L- Online Quizzes


Quizzez 2,3 and 4 with model answer and results Exams and results

GE 306 Course

Engineering Report Writing

GE 306: Engineering Report Writing

CE 499 Course

Senior Design 2 - CE 499

Meeting on 14-4-2015

Second Best paper from Senior Design Projects in 2015

Paper title:

Evaluation of Groundwater Quality Parameters using Multivariate Statistics- a case Study of Majmaah, KSA


Abdullah A. Alzeer

Husam K. Almubark

Maijd M. Almotairi

CE 360-Summer Course

Environmental Engineering I

Welcome to CE360 second Term 2015-2016 

Engineering Practice

 Engineering Practice GE 307

What is your opinion

Contact me

Mobile: 00966598311652

[email protected]

Civil and Environmental Engineering Department
College of Engineering, Majmaah University
Majmaah, P.O. 66, 11952, KSA

Thank you

Your frequent visit to my website has helped  a lot to get the 2nd place in the university competition in the  year 1434-2013... Thanks very mush and please keep following my work

زيارتكم المتكررة لموقعي ساهمت في حصولي على المركز الثاني لاحسن المواقع الشخصية بجامعة المجمعة ...لكم جميعا خالص شكري وتقديري

CE 212 - Summer Course

Properties and Strength of Materials 1

CE 212

Y from PP0 to PP 6 + PDF Power points
Y Midterm #2 + Model Answer + results Exams
Y lab 3 Labs

Solution of Quiz 4 + Results HW

CE 311- Summer Course

Soil Mechanics and Foundation Engineering

CE 311

M2+ model Answer + PP 1-9 = PDF 1-9 all are available

Sheets 2 + 4 with model Answers

Results of M2

إحصائية الموقع

عدد الصفحات: 1412

البحوث والمحاضرات: 1541

الزيارات: 58750