2009-7-27 P,1
Unit 4
Sensing Technology
Chapter Two
&Part4 Extensive Reading@ Part 1 Notes to Text
@Part5 Notes to Passage& Part 2 Word Study
@Part3 Practice on Text @Part6 Practice on Passage
Chapter Study Tasks（ 2）
In this chapter,you will be able to
— Get the general idea of remote sensing
— Tell the difference between passive and active sensors
— Get the general ideas of the texts and extensive
— Complete all the practice required
2009-7-27 P,2
@ Part 1 Notes to Text
1) remote sensing,遥感。
遥感泛指从远处探测、感知物体或事物的技术。即不直接接触物体本身，从远处通过传感器探测和接收来自目标物的信息（如电场、磁场、电磁波、地震波等信息），通过信息的传输及其处理分析，识别物体的属性及其分布的特征的技术。
2) Passive sensors detect natural energy (radiation) that is
emitted or reflected by the object or surrounding area being
observed.被动传感器可以探测出由处于观察中的物体或区域发射或反射出来的自然能（辐射）。
注释,自然界中的一切物体，只要温度在绝对温度零度（－ 273.15摄氏度）以上，都以电磁波的形式时刻不停地向外传送热量，这种传送能量的方式称为辐射（ Radiation）。物体通过辐射所放出的能量，
称为辐射能，简称辐射。所以其实辐射是无处不在的，只是我们平时感觉不到而忽视了它；该句中的分词短语 being observed用作定语，修饰 the object or surrounding area。
Sensing Technology
2009-7-27 P,3
3) The latter,on the other hand,emits energy in order to scan
objects and areas whereupon a passive sensor then detects
and measures the radiation that is reflected or backscattered
from the target,而后者本身散发出来能量，以便对被测物体和区域进行扫描，这样，被动传感器就能探测和测量出由目标物反射或散发出来的射线。
注释,主语 The latter 指代 active sensors；注意 whereupon是连词，
意为“因此，于是”，引导结果状语从句； that is reflected or
backscattered from the target是定语从句，修饰先行词 the
radiation.
End
2009-7-27 P,4 End
1,remote sensing 遥感 11.emission n,散发，发射
2,acquisition n,取得，获得 12.probe n,探测器,探测飞船
3,phenomenon n,现象 13.mit v,散发，发射
4,intimate adj,亲密的；密切的 14.infrared adj,红外线的
5,buoy n,浮标，航标 15.radiometer n,辐射仪，辐射计
6,stand-off adj,对峙的 16.backscatter v,散射
7,pregnancy n,怀孕 17.deforestation n,砍伐森林
8,ultrasound n,超声波 18.glacier n,冰川，冰河
9,resonance n,共振；共鸣 19.in conjunction with 与 … 协力
10.positron n,正电子，阳电子 20.conservation n,保存，保护
& Part 2 Word Study
2009-7-27 P,5
Task 1,Listening training
Dictation of some key words
Directions,You will hear some key words twice,most of which are taken from
the Word Study,Then finish the Crossword Puzzle,(See you book p,)
2,Dictation of some key expressions
Directions,You will hear some key expressions twice,most of which are
taken from this text,Then you are asked to complete the missing words.
@Part3 Practice on Text
1) remote_____________
2) physical or_________________
3) __________gathering information
4) ______________sensors
5) ____________deforestation
6) ___________and conservation
sensing
intimate contact
devices for
passive
monitor
land usage
2009-7-27 P,6
Read and Reply
Directions:Students are required to read aloud the whole text after
the teacher,Then give short answers to the following questions:
a) How does remote sensing acquire information of an object?
b) How many kinds of remote sensing are there? What
are the differences?
Task 2,Read,Write and Translate
By the use of either recording or real-time sensing device that
is not in physical or intimate contact with the object,
There are two,passive and active sensors,Passive sensors
detect natural energy that is emitted or reflected by the object or
surrounding being observed,while the active sensors emit energy
to and receive it from the target.
Remote sensing brings us a lot advantages in many fields,such
as monitoring deforestation,the effect of global warming,depth
sounding of ocean depth,military affairs,national defence amd
natural resource management.
c) What advantages does remote sensing bring us?
2009-7-27 P,7
( )1) By means of physical or intimate contact with an object,
remote sensing can acquire information of it,
( )2)Remote sensing applications can benefit us a lot in many
respects,such as monitoring deforestation,the effect of global
warming and depth sounding of ocean depths.
( )3) Radar is an example of active remote sensing which cannot
be used to establish the location,height,speed and direction of
an object.
( )4) Nowadays,remote sensing is very useful in military affairs
and national security.
( )5) Film photography,infred,charge-coupled devices and radio-
meters are all passive sensors.assive sensors,
Read and Judge
End
F
T
F
T
T
2009-7-27 P,8
Directions:Read the following short passage,Complete it by filling in the missing words.
A.device B.varying C.grain D.such E,addition
F.result G.vary H,depending I.equipped J,required
In 1)______ to one or more sensors,each node in a sensor network
is typically 2)_______ with a radio transceiver or other wireless
communications 3) ______,a small microcontroller,and an energy
source,usually a battery,The size of a single sensor node can
4)_______ from shoebox-sized nodes down to devices the size of
5)_____ of dust,The cost of sensor nodes is similarly variable,
6)_____ from hundreds of dollars to a few cents,7)_____ on the size
of the sensor network and the complexity 8)_____ of individual
sensor nodes,Size and cost constraints on sensor nodes 9)_____ in
corresponding constraints on resources 10)_____ as energy,memory,
computational speed and bandwidth.
Read and Complete
End
E
I
A
G
C
B H
J
F
D
2009-7-27 P,9
1)在今天的信息社会，信息的获取对我们的日常生活是非常重要的。
（ acquisition）
2)遥感技术已被广泛应用于军事，国防和自然资源管理（ remote
sensing technology）
3)主动式遥感能向目标物发射电磁波，同时接受反射回来的电磁波。
（ emit）
4)全球变暖对气候的影响非常明显,已对人类生存构成威胁。 （ global
warming）
5)今天，越来越多的人认识到了土地的科学使用和土地保护的重要性。
（ consevation）
Read and Translate
Directions:Put the following sentences into English,using the words or phrases given.
End
In today’ s information age,acqusition
of information is very important to our daily life.
Remote sensing is widely used in military
affairs,national defence and natural resource management.
Active sensors emit electromagnetic waves to and,at
the same time,receive them from the target
The effect of global warming on the climate is quite
obvious,which poses a threat to the survival of human beings.
Today more and more people have realized the importance of
scientific usage and conservation of land.
2009-7-27 P,10
Image dissector and Orthicon
The image dissector(分析者 ) was invented by Philo Farnsworth,one of
the pioneers of electronic television,in 1927,It is a type of cathode
(负极 ) ray tube occasionally employed as a camera in industrial
television systems,The image dissector had very poor light
sensitivity,and was useful only where scene illumination(照明 )
exceeded 685 cd/m2,but it was ideal for high light levels such as
when engineers wanted to monitor the bright,hot interior(内部 )of an
industrial furnace,Owing to its lack of sensitivity,the image
dissector was rarely used in TV broadcasting,except to scan film
and other transparencies,It was,however,the beginning of the
electronic TV age.
The image dissector sees the outside world through a glass lens,
which focuses an image through the clear glass wall of the tube
onto a special plate which is coated with a layer of caesium oxide(氧化铯 ),When light strikes caesium oxide,the material emits electrons,
somewhat like a mirror that reflects an image made of electrons,
rather than light,These electrons are aimed and accelerated by
electric and magnetic fields onto the dissector's single electron
&Part4 Extensive Reading
2009-7-27 P,11
detector so that only a small portion of the electron image hits the
detector at any given moment,As time passes the electron image is
deflected back and forth and up and down so that the entire image,
portion by portion,can be read by the detector,The output from the
detector is an electric current whose magnitude (大小 )is a
measure of brightness at a specific point on the image,Electrons
that do not hit the single detector are wasted,rather than stored on
the target as in the image orthicon(摄象管 )which accounts in part for
its low sensitivity,It has no "storage characteristic".
The image orthicon tube (often abbreviated as IO) was common
until the 1960s,A combination of Farnsworth's image dissector and
RCA's orthicon technologies,it replaced the iconoscope(光电析象管 )/orthicon,which required a great deal of light to work adequately,
While the iconoscope and the intermediate orthicon used
capacitance(电容 ) between a multitude of small but discrete light
sensitive collectors and an isolated signal plate for reading video
2009-7-27 P,12
information,the IO employed direct charge readings out of a
continuous electronically charged collector,The resultant(组合的 )
signal was immune to most extraneous(外部的 ) signal "crosstalk"
from other parts of the target,and could yield extremely detailed
images,For instance,IO cameras were used for capturing
Apollo/Saturn rockets nearing orbit,as only they could provide
sufficient detail.
A properly constructed image orthicon could take television
pictures by candlelight owing to the more ordered light-sensitive
area and the presence of an electron multiplier at the base of the
tube,which operated as a high-efficiency amplifier,It also had a
logarithmic(数面的 ) light sensitivity curve similar to the human eye,
so the picture looked more natural,Its defect was that it tended to
flare if a shiny object in the studio caught a reflection of a light,
generating a dark halo(光环 )around the object on the picture,Image
orthicons were used extensively in the early color television
cameras,where their increased sensitivity was essential to
overcome their very inefficient optical system.
End
2009-7-27 P,13
@Part5 Notes to Passage
1)Philo Farnsworth菲洛 ·法思华斯注释,法思华斯 Philo T,Farnsworth (1906-1971)生于美国犹他州的法华沃斯，是一位卓越的发明家，他发明了世界上第一部全电子式的电视在 1927年，当时他才 21岁。 在 1928年 9月，他公开的实验了全电子电视影像的传输。重要贡献：电子影像分解摄影机
(Electronic Image Dissector)。
2） It is a type of cathode ray tube occasionally employed as a
camera in industrial television systems,这是一种偶尔用作电视系统中摄像机的阴极射线管。
注释,employed是过去分词，作定语，修饰先行词 cathode ray
tube.
2009-7-27 P,14
3） While the iconoscope and the intermediate orthicon used
capacitance between a multitude of small but discrete light
sensitive collectors and an isolated signal plate for reading
video information,the IO employed direct charge readings
out of a continuous electronically charged collector,光电析像管及中级摄像管使用大量小而离散感光器和用于阅读视频信息的隔离信号板之间的电容，不过光电摄像管则可利用连续电子充电接收器的直接充电读数。
注释,该句的主句是 the IO employed direct charge readings … ；
while是等立连词，意思是“尽管，然而”。用以强调两者间的对比；短语 out of相当于 from。
2009-7-27 P,15 End
4） A properly constructed image orthicon could take television
pictures by candlelight owing to the more ordered light-
sensitive area and the presence of an electron multiplier at
the base of the tube,which operated as a high-efficiency
amplifier,理想的摄像管能借助于烛光拍电视画面，这是因为在摄像管下端有感光区和电子倍增器，这种摄像管就是一个高效率放大器。
注释,介词短语 owing to 表原因，相当于 because of; 关系代词
which引导非限制性定语从句，修饰先行词 the tube。
2009-7-27 P,16
1.Listening Challenge
Spot Dictation
Directions,The following passage will be heard 3 times,During the second time,you
are required to put the missing words or phrases in the numbered blanks according to
what you hear,The third time is for you to check your answers,Now the passage
begins.
Vladimir Zworykin patented the idea,in May 1931,of projecting an image on
a special plate which was 1) _________ with a chemical photoemissive
mosaic 2) __________ of granules of material,a pattern 3) _____________
to the receptors of the human eye,Emission of photoelectrons from each
granule in 4) ____________ to the amount of light 5) __________ in a charge
image being formed on the mosaic,Each granule,6) ___________ with the
conductive plate behind the mosaic,formed a small capacitor,all of these
having a common plate,An electron beam was then swept across the face
of the plate from an electron gun,discharging the capacitors in 7)
______________; the resulting changes in potential at the metal plate
constituted the picture signal,8) ______ the image dissector the Zworykin
model was much more 9) __________,to about 75 000 lux,It was also
easier to manufacture and produced a very clear 10) ________.
@Part6 Practice on Passage
End
covered
consisting comparable
proportion resulted
together
succession
Unlike
sensitive
image
2009-7-27 P,17
End of this Unit
Unit 4
Sensing Technology
Chapter Two
&Part4 Extensive Reading@ Part 1 Notes to Text
@Part5 Notes to Passage& Part 2 Word Study
@Part3 Practice on Text @Part6 Practice on Passage
Chapter Study Tasks（ 2）
In this chapter,you will be able to
— Get the general idea of remote sensing
— Tell the difference between passive and active sensors
— Get the general ideas of the texts and extensive
— Complete all the practice required
2009-7-27 P,2
@ Part 1 Notes to Text
1) remote sensing,遥感。
遥感泛指从远处探测、感知物体或事物的技术。即不直接接触物体本身，从远处通过传感器探测和接收来自目标物的信息（如电场、磁场、电磁波、地震波等信息），通过信息的传输及其处理分析，识别物体的属性及其分布的特征的技术。
2) Passive sensors detect natural energy (radiation) that is
emitted or reflected by the object or surrounding area being
observed.被动传感器可以探测出由处于观察中的物体或区域发射或反射出来的自然能（辐射）。
注释,自然界中的一切物体，只要温度在绝对温度零度（－ 273.15摄氏度）以上，都以电磁波的形式时刻不停地向外传送热量，这种传送能量的方式称为辐射（ Radiation）。物体通过辐射所放出的能量，
称为辐射能，简称辐射。所以其实辐射是无处不在的，只是我们平时感觉不到而忽视了它；该句中的分词短语 being observed用作定语，修饰 the object or surrounding area。
Sensing Technology
2009-7-27 P,3
3) The latter,on the other hand,emits energy in order to scan
objects and areas whereupon a passive sensor then detects
and measures the radiation that is reflected or backscattered
from the target,而后者本身散发出来能量，以便对被测物体和区域进行扫描，这样，被动传感器就能探测和测量出由目标物反射或散发出来的射线。
注释,主语 The latter 指代 active sensors；注意 whereupon是连词，
意为“因此，于是”，引导结果状语从句； that is reflected or
backscattered from the target是定语从句，修饰先行词 the
radiation.
End
2009-7-27 P,4 End
1,remote sensing 遥感 11.emission n,散发，发射
2,acquisition n,取得，获得 12.probe n,探测器,探测飞船
3,phenomenon n,现象 13.mit v,散发，发射
4,intimate adj,亲密的；密切的 14.infrared adj,红外线的
5,buoy n,浮标，航标 15.radiometer n,辐射仪，辐射计
6,stand-off adj,对峙的 16.backscatter v,散射
7,pregnancy n,怀孕 17.deforestation n,砍伐森林
8,ultrasound n,超声波 18.glacier n,冰川，冰河
9,resonance n,共振；共鸣 19.in conjunction with 与 … 协力
10.positron n,正电子，阳电子 20.conservation n,保存，保护
& Part 2 Word Study
2009-7-27 P,5
Task 1,Listening training
Dictation of some key words
Directions,You will hear some key words twice,most of which are taken from
the Word Study,Then finish the Crossword Puzzle,(See you book p,)
2,Dictation of some key expressions
Directions,You will hear some key expressions twice,most of which are
taken from this text,Then you are asked to complete the missing words.
@Part3 Practice on Text
1) remote_____________
2) physical or_________________
3) __________gathering information
4) ______________sensors
5) ____________deforestation
6) ___________and conservation
sensing
intimate contact
devices for
passive
monitor
land usage
2009-7-27 P,6
Read and Reply
Directions:Students are required to read aloud the whole text after
the teacher,Then give short answers to the following questions:
a) How does remote sensing acquire information of an object?
b) How many kinds of remote sensing are there? What
are the differences?
Task 2,Read,Write and Translate
By the use of either recording or real-time sensing device that
is not in physical or intimate contact with the object,
There are two,passive and active sensors,Passive sensors
detect natural energy that is emitted or reflected by the object or
surrounding being observed,while the active sensors emit energy
to and receive it from the target.
Remote sensing brings us a lot advantages in many fields,such
as monitoring deforestation,the effect of global warming,depth
sounding of ocean depth,military affairs,national defence amd
natural resource management.
c) What advantages does remote sensing bring us?
2009-7-27 P,7
( )1) By means of physical or intimate contact with an object,
remote sensing can acquire information of it,
( )2)Remote sensing applications can benefit us a lot in many
respects,such as monitoring deforestation,the effect of global
warming and depth sounding of ocean depths.
( )3) Radar is an example of active remote sensing which cannot
be used to establish the location,height,speed and direction of
an object.
( )4) Nowadays,remote sensing is very useful in military affairs
and national security.
( )5) Film photography,infred,charge-coupled devices and radio-
meters are all passive sensors.assive sensors,
Read and Judge
End
F
T
F
T
T
2009-7-27 P,8
Directions:Read the following short passage,Complete it by filling in the missing words.
A.device B.varying C.grain D.such E,addition
F.result G.vary H,depending I.equipped J,required
In 1)______ to one or more sensors,each node in a sensor network
is typically 2)_______ with a radio transceiver or other wireless
communications 3) ______,a small microcontroller,and an energy
source,usually a battery,The size of a single sensor node can
4)_______ from shoebox-sized nodes down to devices the size of
5)_____ of dust,The cost of sensor nodes is similarly variable,
6)_____ from hundreds of dollars to a few cents,7)_____ on the size
of the sensor network and the complexity 8)_____ of individual
sensor nodes,Size and cost constraints on sensor nodes 9)_____ in
corresponding constraints on resources 10)_____ as energy,memory,
computational speed and bandwidth.
Read and Complete
End
E
I
A
G
C
B H
J
F
D
2009-7-27 P,9
1)在今天的信息社会，信息的获取对我们的日常生活是非常重要的。
（ acquisition）
2)遥感技术已被广泛应用于军事，国防和自然资源管理（ remote
sensing technology）
3)主动式遥感能向目标物发射电磁波，同时接受反射回来的电磁波。
（ emit）
4)全球变暖对气候的影响非常明显,已对人类生存构成威胁。 （ global
warming）
5)今天，越来越多的人认识到了土地的科学使用和土地保护的重要性。
（ consevation）
Read and Translate
Directions:Put the following sentences into English,using the words or phrases given.
End
In today’ s information age,acqusition
of information is very important to our daily life.
Remote sensing is widely used in military
affairs,national defence and natural resource management.
Active sensors emit electromagnetic waves to and,at
the same time,receive them from the target
The effect of global warming on the climate is quite
obvious,which poses a threat to the survival of human beings.
Today more and more people have realized the importance of
scientific usage and conservation of land.
2009-7-27 P,10
Image dissector and Orthicon
The image dissector(分析者 ) was invented by Philo Farnsworth,one of
the pioneers of electronic television,in 1927,It is a type of cathode
(负极 ) ray tube occasionally employed as a camera in industrial
television systems,The image dissector had very poor light
sensitivity,and was useful only where scene illumination(照明 )
exceeded 685 cd/m2,but it was ideal for high light levels such as
when engineers wanted to monitor the bright,hot interior(内部 )of an
industrial furnace,Owing to its lack of sensitivity,the image
dissector was rarely used in TV broadcasting,except to scan film
and other transparencies,It was,however,the beginning of the
electronic TV age.
The image dissector sees the outside world through a glass lens,
which focuses an image through the clear glass wall of the tube
onto a special plate which is coated with a layer of caesium oxide(氧化铯 ),When light strikes caesium oxide,the material emits electrons,
somewhat like a mirror that reflects an image made of electrons,
rather than light,These electrons are aimed and accelerated by
electric and magnetic fields onto the dissector's single electron
&Part4 Extensive Reading
2009-7-27 P,11
detector so that only a small portion of the electron image hits the
detector at any given moment,As time passes the electron image is
deflected back and forth and up and down so that the entire image,
portion by portion,can be read by the detector,The output from the
detector is an electric current whose magnitude (大小 )is a
measure of brightness at a specific point on the image,Electrons
that do not hit the single detector are wasted,rather than stored on
the target as in the image orthicon(摄象管 )which accounts in part for
its low sensitivity,It has no "storage characteristic".
The image orthicon tube (often abbreviated as IO) was common
until the 1960s,A combination of Farnsworth's image dissector and
RCA's orthicon technologies,it replaced the iconoscope(光电析象管 )/orthicon,which required a great deal of light to work adequately,
While the iconoscope and the intermediate orthicon used
capacitance(电容 ) between a multitude of small but discrete light
sensitive collectors and an isolated signal plate for reading video
2009-7-27 P,12
information,the IO employed direct charge readings out of a
continuous electronically charged collector,The resultant(组合的 )
signal was immune to most extraneous(外部的 ) signal "crosstalk"
from other parts of the target,and could yield extremely detailed
images,For instance,IO cameras were used for capturing
Apollo/Saturn rockets nearing orbit,as only they could provide
sufficient detail.
A properly constructed image orthicon could take television
pictures by candlelight owing to the more ordered light-sensitive
area and the presence of an electron multiplier at the base of the
tube,which operated as a high-efficiency amplifier,It also had a
logarithmic(数面的 ) light sensitivity curve similar to the human eye,
so the picture looked more natural,Its defect was that it tended to
flare if a shiny object in the studio caught a reflection of a light,
generating a dark halo(光环 )around the object on the picture,Image
orthicons were used extensively in the early color television
cameras,where their increased sensitivity was essential to
overcome their very inefficient optical system.
End
2009-7-27 P,13
@Part5 Notes to Passage
1)Philo Farnsworth菲洛 ·法思华斯注释,法思华斯 Philo T,Farnsworth (1906-1971)生于美国犹他州的法华沃斯，是一位卓越的发明家，他发明了世界上第一部全电子式的电视在 1927年，当时他才 21岁。 在 1928年 9月，他公开的实验了全电子电视影像的传输。重要贡献：电子影像分解摄影机
(Electronic Image Dissector)。
2） It is a type of cathode ray tube occasionally employed as a
camera in industrial television systems,这是一种偶尔用作电视系统中摄像机的阴极射线管。
注释,employed是过去分词，作定语，修饰先行词 cathode ray
tube.
2009-7-27 P,14
3） While the iconoscope and the intermediate orthicon used
capacitance between a multitude of small but discrete light
sensitive collectors and an isolated signal plate for reading
video information,the IO employed direct charge readings
out of a continuous electronically charged collector,光电析像管及中级摄像管使用大量小而离散感光器和用于阅读视频信息的隔离信号板之间的电容，不过光电摄像管则可利用连续电子充电接收器的直接充电读数。
注释,该句的主句是 the IO employed direct charge readings … ；
while是等立连词，意思是“尽管，然而”。用以强调两者间的对比；短语 out of相当于 from。
2009-7-27 P,15 End
4） A properly constructed image orthicon could take television
pictures by candlelight owing to the more ordered light-
sensitive area and the presence of an electron multiplier at
the base of the tube,which operated as a high-efficiency
amplifier,理想的摄像管能借助于烛光拍电视画面，这是因为在摄像管下端有感光区和电子倍增器，这种摄像管就是一个高效率放大器。
注释,介词短语 owing to 表原因，相当于 because of; 关系代词
which引导非限制性定语从句，修饰先行词 the tube。
2009-7-27 P,16
1.Listening Challenge
Spot Dictation
Directions,The following passage will be heard 3 times,During the second time,you
are required to put the missing words or phrases in the numbered blanks according to
what you hear,The third time is for you to check your answers,Now the passage
begins.
Vladimir Zworykin patented the idea,in May 1931,of projecting an image on
a special plate which was 1) _________ with a chemical photoemissive
mosaic 2) __________ of granules of material,a pattern 3) _____________
to the receptors of the human eye,Emission of photoelectrons from each
granule in 4) ____________ to the amount of light 5) __________ in a charge
image being formed on the mosaic,Each granule,6) ___________ with the
conductive plate behind the mosaic,formed a small capacitor,all of these
having a common plate,An electron beam was then swept across the face
of the plate from an electron gun,discharging the capacitors in 7)
______________; the resulting changes in potential at the metal plate
constituted the picture signal,8) ______ the image dissector the Zworykin
model was much more 9) __________,to about 75 000 lux,It was also
easier to manufacture and produced a very clear 10) ________.
@Part6 Practice on Passage
End
covered
consisting comparable
proportion resulted
together
succession
Unlike
sensitive
image
2009-7-27 P,17
End of this Unit
