shell text (Mayte)

Question 1

what is the Beer-Lambert law

Answer 1

Question 2

what is cone of acceptance

Answer 2

Question 3

laser pulses are directed to the fiber line by
means of a _________.

Answer 3

Question 4

temperature standard deviation will increase with _____ even if the standard deviation of the Raman signals are constant.

Answer 4

Question 5

a DTS system’s resolution should be stated in terms of fiber length and sampling time.

Answer 5

Question 6

how is the speed of light in a fiber determined

Answer 6

Question 7

If the sensitivity is known, the observed temperature
log is made up sum of three components:

Answer 7

Question 8

the weakest of the backscattered waves, resulting from molecular and atomic vibrations, are the ____Bands

Answer 8

Question 9

If the velocity of light in the fiber is v, a ____can be opened at some time t to capture that backscattered light.

Answer 9

Question 10

why do most DTS measurements use multimode fiber

Answer 10

Question 11

Question 12

The refractive index of the core is approximately
___% greater than the cladding thereby
assuring the containment of the laser light pulse
within the core.

Answer 12

Question 13

what does water do to fiber

Answer 13

Question 14

what are the accuracy and resolution definitions and differences

Answer 14

Question 15

This light pulse is, in effect, a travelling ____ moving through the fiber line and relaying back temperature information

Answer 15

Question 16

what is the sampling resolution

Answer 16

Question 17

red shift is a _____ in wavelength and blue shift is a ______ in wavelength

Answer 17

Question 18

The Raman signal is the signal used for evaluation of temperature. It is sufficiently strong and has a unique temperature dependence. Its wavelength is also shifted substantially (about ____/Nm) from the main Rayleigh peak,
thereby allowing the dominant Rayleigh and Brillouin peaks to be filtered out

Answer 18

Question 19

During backscattering, the energized lattice and molecules then give off light having wavelengths at _______ the incident wave.

Answer 19

Question 20

what is the temperature equation

Answer 20

Question 21

Resolution can be expressed as ______
of the temperature measurement

Answer 21

Question 22

what is Snell’s Law

Answer 22

Question 23

______ laser pulses and smaller time
windows are required to better detect short length high temperature nanomalies.

Answer 23

Question 24

Laser pulses are directed to the fiber line by
means of a directional coupler. The fiber optic line then passes through a(n) ______ before going into the fiber

Answer 24

Question 25

what is a graded index

Answer 25

Question 26

Optical Time Domain Reflectometry (OTDR) is used to access what and with what type of wave

Answer 26

Question 27

The main backscattered wave is at the wavelength of the launched wave and is called the ____ peak or band. This is by far the _____ signal returned.

Answer 27

Question 28

the stokes and antistokes signals signal on the backscatter vary because

Answer 28

Question 29

what is the equation to determine the lenth of a light pulse

Answer 29

Question 30

Total internal reflection is based on what law

Answer 30

Question 31

what is the equation for overstuff

Answer 31

Question 32

what is T_ref and T₀

Answer 32

Question 33

what is optical overstuff

Answer 33

Question 34

what is the equation for the energy of the returning Ramen backscatter

Answer 34

Question 35

how long is the lightpulse to measure the fiber

Answer 35

Question 36

what are the x and y axis for a typical Optical Time Domain Reflectometry (OTDR) graph

Answer 36

Question 37

For singlemode fiber, longer distances requires ____ and \_\_\_\_\_

Answer 37

Question 38

What is the equation to determine window size required to achieve a one meter length resolution along the fiber

Answer 38

Question 39

what is the equation for overstuff of the fiber caused by its own weight

Answer 39

Question 40

how is differential loss determined in a DTS wrap back

Answer 40

Question 41

what are two definitions of spacial resolution

Answer 41

Question 42

Except for certain special quality control tests, the _______ signal is usually filtered and suppressed.

Answer 42

Question 43

Those waves associated with the lattice vibrations show up as _____ lines or peaks on the backscatter spectrum.

Answer 43

Question 44

When that pulse enters the fiber, it is said to be \_\_\_\_\_

Answer 44