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A Report On-
Under subject of
B. E. IV, Semester – VII
(Instrumentation & Control Branch)
Submitted by:

Sr. Name of student Enrolment No.
2.JUHI FADIA 160283117004

Prof. Sampan Shah
(Faculty Guide)
(Head of the Department)
Academic year (2018-2019)

1 Introduction
Problem Summary
1.2 Aim and objectives of the project
1.3 Problem Specifications
1.4 Brief literature review and Prior Art Search (PAS) about the project
1.5 Plan of their work
1.6 Materials / Tools required.
2 Design: Analysis, Design Methodology, and Implementation Strategy.
3 Implementation:
4 Results and Future Scope
5 References 39

Problem Summary
Our project makes a difficult job of handling babies and infants really easy. Stakeholders of this project are not just babies and mothers but all the family members and care takers also. Based on the survey we did, we came to a conclusion to name our domain as ” BABYCARE.” We went through the problems these people were facing and we realized in these busy life where both of the parents are working professionals, have a hard time to manage their babies. For these, we interacted with mothers and discussed about the issues they are facing while nurturing their babies, where we analysed the problems and had blur clarity of the product we are willing to make. Later, we realized this problem is not limited to domestic level only but extends up to hospital and health sector. We visited children’s hospital and interacted with pediatricians also and came to know that they are facing difficulties in continuous monitoring of health of baby and keeping its record, all these manually.
Looking such scenarios, decided to try our hands on building a product which can offer satisfactory solution to these problem and proves helpful to domestic as well as medical level. Finally, we decided to make a product called – smart baby cradle, which would provide efficient care.

Aim and objectives of the project:
As mentioned in the previous topic, the problem is of considerable concern, and it becomes mandatory to find some solution to it. Finally, after research, analysis, discussion, study and review, we came to a conclusion to make an innovative product called “SMART BABY CRADLE.” The proposed work is to create and develop a smart baby cradle using intelligent modules.

Problem Specifications
This project will involve designing a smart intelligent baby cradle for the purpose of making tedious job of baby care easy and efficient. This baby cradle doesn’t need any assistance of the second person, but the stakeholder can operate and monitor it, all by himself. It is fully battery operated and can be recharged at regular intervals. Following problems are considered while designing a product:
Conventionally, one requires mother, granny or the other person constantly with a baby to take his proper care. At times, it is not possible to be that one person or find that one person, and efficiency may also be less. As depicted in the figure, another person is always required while navigating. With this smart cradle, this problem can be eradicated and continuous manual monitoring is not required.

2. Providing comfort:
On sensing the signals, which needs to be manipulated, cradle will automatically start swinging at predefined speed, and helps baby to sleep peacefully. Whereas in conventional cradle you need to do it manually, which is not as efficient as this one.

Urine and potty detection:
As the baby pees timely and it’s really imprtant to get him fresh and clean to maintain hygeine atmosphere and health, there’s a detector and alarm system which makes a mother or care taker cautious. This helps baby to stay happy and fresh.

4. Body temperature monitoring:
Babies tend to fall ill quickly and need to be taken constant care. There is a constant temperature detection module which constantly senses the body temperature and notifies through alarm, if it exceeds the limit. Thus, helps in getting aware of the condition immediately.

5. Live display:
Display is incorporated to showcase and indicate condition of baby and body temperature. It receives real time data from the systems and display the results accordingly. It helps in knowing condition and status at a glance.

6. Data log:
Data can be logged to keep a record. In hospital, when baby is under observation, it is necessary to check the body temperature of baby, periodically. This is inefficient and tedious at some point. This automatic data logging system records and saves the data up to seven consecutive days and prevents all these chaos.

7. Speed control:
Speed of swinging should be really moderate and needs to be controlled for safety. This is achieved using special speed controlling technique.

Brief literature review and Prior Art Search (PAS) about the project
After several studies and survey, it has shown that though both babies and caretakers and nurses/doctors can be happy with smart and powered baby cradles; there is a segment of the working parents community finding it challenging to take care of their babies independently. The proposed work is to design and develop a smart and intelligent cradle using a voice intelligent modules and speed control system. It can be used economically with less effort by the users so that they can use it easily. To assist this population, researchers have used technologies originally create “smart cradles.” Smart cradles have been the topic of research since so many years. Various smart features were also incorporated. But the major downside of those cradles is their cost. It costs really high and people find it uneconomical to use. Psychologically, parents were also not adapting the thought of leaving a baby with machine. We yarned to build up a machine which bridges this notion and helps having faith in it as this product is completely reliable and full safety features. Safety and reliability shall be the first considered while designing a baby care product and we compromise this at no level. Yang Hu proposed calculation of altering the bassinet influencing degree by the sensor signals. The bassinet is made up of a versatile influencing gadget and different sensor system. While infant is crying, the sensor system can judge the reason as indicated by identifying the parameters, giving the distinctive signs to control circuit. In the meantime, the bassinet begins to influence marginally. The influencing mood can be balanced as indicated by the parameters from child status. They utilize three wet sensor situated in the bassinet base, one at the focus and others at left and right of the base.
A cradle is one of the safest place for baby to comfort sleep and babies’ likes the cradle and they enjoy in the cradle because they are habituate to rocking and all babies have already rocked in their mom’s wombs. During the time of pregnancy whenever mother breathing and movement of mother as well as through heart beat they enjoy rocking through mentioned activity. The Vestibules is established from the 3rd month onwards and fully established at the time of birth. This the reason why baby feels comfortable whenever the cradle swings.

Prior art search
Gim Wong introduce and electronic gadget that can be connected to the traditional essentially mounted type crib. Which is incited by the child cry voice got by the amplifier gives short toss shaking activity to bunk the pushing and pulling on the footer heard board. There is affectability control so child voice only execute the shaking action and there is clock to control the duration of rocking action. Anritha Ebenezer gives an approach to plan to design the automatic baby cradle for cry detection. Whenever analyze the sound intensity the cradle stars swings. It has approx. six times per minute. It has wet sensor to shows infant wets, at what over point infant wets resistance would change thus sending a signal. Different sensor such like temperature sensor to show baby temperature, respiratory sensor that signs in apnea condition. Module has been used to send the SMS to the guardians in case baby is not stopping crying as well as in the case of bed-wet.

Application of Automatic cradle:
baby care centres
Feedback in Computer Based Learning environment
Plan of work:

Initially, we will observe the problems and try to understand those in detail. Finally, as we have described in PPR’s, we will move on to the next stage- deciding and implementation of features.

Before that, Interfacing different modules with Arduino has to be understood carefully and finally implementation.

After learning all this, a prototype will be made that comprises these features and will be implemented on a small base.

Further, realising the results, we get, more powerful and robust design would be made and implemented on an actual cradle which resembles exactly the real market product.

Once a product is made, customer revalidation will be made to take reviews from them to know the sustainability of our product.

Materials/Tools required
As far as technology is concerned, SMART CRADLE invokes all types of system that are trending so far like Speed Control, Voice reorganisation and Obstacle detector, Water detector. The whole system is based on Arduino (Open Source) which is very widely used, available and easy to sort out the incorporated mistakes.

While designing our product, Instruments/Components that are needed are a Brushed/Brushless D.C. Motor, metal base and pillars, Spongy materials to increase the comfort, Rechargeable battery to give a supply to a system. Following block diagram shows the overall process, how the system will work.

As can be seen from the figure, there is a controlling device, which in our case we will use an Arduino. Power supply is connected to motor and as well as controller. Power supply provides power to the system to run which is 12V DC battery. Further, motor is connected to the cradle and all the above mentioned features which consists of sensors are incorporated here. Indicating devices consist of alarm, diplay and annunciators which draws ones attention.

Motor is a main part used in cradle, which is connected to the 12 V DC supply. It is used to swing the cradle.

Cradle is the bed where your baby can sleep comfortably. It is specially designed for your baby which can provide baby a pleasant sleep.


Here we have used a controlling component to detect the controlling signal and pass it to the system.
Indicating devices are the device which sense the indicating signals from controlling device and pass this signals to the indicator. LED ; Buzzer

The power supply is used to operate the whole cradle system. In motor 12 V , 5 Amp. DC supply is applied to operate. All controlling devices are operated at 5 V, 1 Amp. DC supply.

Arduino Compiler
The Arduino UNO is an open-source microcontroller board based on the Microchip ATmega328P microcontroller and developed by The board is equipped with sets of digital and analog input/output (I/O) pins that may be interfaced to various expansion boards (shields) and other circuits.1 The board has 14 Digital pins, 6 Analog pins, and programmable with the Arduino IDE (Integrated Development Environment) via a type B USB cable.4 It can be powered by a USB cable or by an external 9 volt battery, though it accepts voltages between 7 and 20 volts. It is also similar to the Arduino nano and Leonardo.56 The hardware reference design is distributed under a Creative Commons Attribution Share-Alike 2.5 license and is available on the Arduino website. Layout and production files for some versions of the hardware are also available. “Uno” means one in Italian and was chosen to mark the release of Arduino Software (IDE) 1.0.1 The Uno board and version 1.0 of Arduino Software (IDE) were the reference versions of Arduino, now evolved to newer releases.4 The Uno board is the first in a series of USB Arduino boards, and the reference model for the Arduino platform.3 The ATmega328 on the Arduino Uno comes preprogrammed with a bootloader that allows uploading new code to it without the use of an external hardware programmer.3 It communicates using the original STK500 protocol.1The Uno also differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it uses the Atmega16U2 (Atmega8U2 up to version R2) programmed as a USB-to-serial converter.

Under Electrical Motor DC motor in simple words is a device that converts direct current (electrical energy) into mechanical energy. It’s of vital importance for the industry today, and is equally important for engineers to look into the working principle of DC motor in details that has been discussed in this article. In order to understand the operating principle of dc motor we need to first look into its constructional feature.

Working principle of DC Motor mainly depends upon Fleming Left Hand rule. In a basic dc motor, an armature is placed in between magnetic poles. If the armature winding is supplied by an external dc source, current starts flowing through the armature conductors. As the conductors are carrying current inside a magnetic field, they will experience a force which tends to rotate the armature. Suppose armature conductors under N poles of the field magnet, are carrying current downwards (crosses) and those under S poles are carrying current upwards (dots).

By applying Fleming’s Left hand Rule, the direction of force F, experienced by the conductor under N poles and the force experienced by the conductors under S
poles can be determined. It is found that at any instant the forces experienced by the conductors are in such a direction that they tend to rotate the armature.

Again, due this rotation the conductors under N – poles come under S – pole and the conductors under S – poles come under N – pole. While the conductors go form N – poles to S – pole and S – poles to N – pole, the direction of current through them, is reversed by means of commutator. Due to this reversal of current, all the conductors come under N – poles carry current in downward direction and all the conductors come under S – poles carry current in upward direction as shown in the figure. Hence, every conductor comes under N – pole experiences force in same direction and same is true for the conductors come under S – poles.

Power supply:

Power supply is a device which converts the AC supply into DC supply. Basically the parts used in power supply are transformer, bridge rectifier ,integrated circuit, resistors and capacitors. The description of the parts is described below.

A transformer is an electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. Commonly, transformers are used to increase or decrease the voltages of alternating current in electric power applications. A varying current in the transformer’s primary winding creates a varying magnetic flux in the transformer core and a varying magnetic field impinging on the transformer’s secondary winding. This varying magnetic field at the secondary winding induces a varying electromotive force (EMF) or voltage in the secondary winding. Making use of Faraday’s Law in conjunction with high magnetic permeability core properties, transformers can thus be designed to efficiently change AC voltages from one voltage level to another within power networks. Since the invention of the first constant potential transformer in 1885, transformers have become essential for the transmission, distribution , and utilization of alternating current electrical energy. A wide range of transformer designs are encountered in electronic and electric power applications. Transformers range in size from RF transformers less than a cubic centimetre in volume to units interconnecting the power grid weighing hundreds of tons.


A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. The process is known as rectification . Physically, rectifiers take a number of forms, including vacuum tube diodes , mercury-arc valves, copper and selenium oxide rectifiers, semiconductor diodes , silicon-controlled rectifiers and other silicon-based semiconductor switches.

Rectifier circuits may be single-phase or multi- phase (three being the most common number of phases). Most low power rectifiers for domestic equipment are single-phase, but three-phase rectification is very important for industrial applications and for the transmission of energy as DC ( HVDC ).

A resistor is a two-terminal electronic component designed to oppose an electric current by producing a voltage drop between its terminal in proportion to the current, that is in accordance with Ohm’s Law :V=IR
Resistors are used as part of electrical networks and electronic circuits. They are extremely commonplace in most electronic equipment. Practical resistors can be made of various compounds and films, as well as resistance wire (wire made of a high resistivity alloy, such as nickel/chromel)

The primary characteristics of resistor are resistance and the power they can dissipate. Its unit is ohm ?.

A capacitor or condenser is a passive electronic component consisting of a pair of conductors separated by a dielectric. When a voltage potential difference exists between the conductors, an electric field is present in the dielectric. This field stores energy and produces a mechanical force between the plates. The effect is greatest between wide flate, parallel, narrowly separated conductors.

An idea capacitor is characterized by a single constant value, capacitance, which is the ratio of the electric charge on each conductor to the potential difference between them.


initially when cradle is turned on, the current values of all the sensors are recorded.

If mic value is greater than 60, the message “baby is crying” will be sent via SMS and it will be displayed on a screen and emergency alert alarm will be triggered.

If it is less than 60, then continuous monitoring will take place and values would be recorded continuously.

If water sensor triggers, the message “baby is wet” will be sent via SMS and it will be displayed on a screen and emergency alert alarm will be triggered.

If it doesn’t trigger, then continuous monitoring will take place and values would be recorded continuously.

If temperature value is greater than 98F, the message “baby’s temperature is high” will be sent via SMS and it will be displayed on a screen and emergency alert alarm will be triggered.

If it is less than 98, then continuous monitoring will take place and values would be recorded continuously.

If load value is less than 20, the message “baby out of cradle” will be sent via SMS and it will be displayed on a screen and emergency alert alarm will be triggered.

If it doesn’t trigger, then continuous monitoring will take place and values would be recorded continuously.

Thus, continuous and automatic baby monitoring takes place through this smart baby cradle.

Design: Analysis, Design Methodology, and Implementation Strategy
Empathy canvas:-
This is the first step of the project or problem. In this canvas, we have mentioned the users to our problems, stakeholders, activities and some touching stories related to it.
It basically involves users who are going to use this product. They are the one who takes care of the babies and babies themselves.

Care takers
Hospital staff
A stakeholder means a person or firm with interest.
In this stage, we find the user who will directly or indirectly relate to users.

Activities here include the programs that are being carried out at a particular place of research. As we have been to children’s hospital, and interacted with parents, following activities were being carried out.

Baby bath
body check up
Medical care
Story Boarding:-
Happy and Sad stories have been mentioned in the canvas below. Some happy and motivational stories are being mentioned like how a working mother got relief from the chaos of tedious baby caring. Some sad and emotional stories are also mentioned likewise.

Ideation canvas:-
This is the second step of the project or problem. From the user canvas, we have an idea what are the people? In ideation canvas, we carried out which type of activities is related to our project and people, the situation and location regarding activities. Then after, we find the possible solutions.
People here are those, who are directly related to this product and people using this product. The following list mentions the people who are directly related to it and are the most important assets to this domain.

Family members
care takers
Activities which have been mentioned previously are mentioned here too.

baby bathing
Situation and Location are the places where this product can be used. It describes when to use this product, where and why. For, e.g., it is difficult to check the body temperature of baby periodically and keep a record, automatic cradle does this automatically. Similar situations and places have been mentioned below in the form of a list.

Child care centres
Props/Possible Solutions:-
For working parents and children’s hospital staff, some of the possible solutions have been penned down below as a list.

Continuous monitoring
Live updates through SMS
Automatic swinging
Efficient care
Soothing sleep
Stress free

3. Product development canvas:-
The third step is the development of the product. From possible solutions, we have an idea of what is a product? In this canvas, following things are being carried out.

The purpose of fabricating our product is listed below.

Stress free
Efficient care
Hospital staff
Care takers
Product Experience:-
The customer should experience the essence of this product which is mentioned below.

Product function:-
Product features:-
Speed control
Obstacle avoidance
Temperature sensing, displaying and recoredingUrine and potty detection
Notifying and awareness through SMS
Rain sensor
PIR sensor
Speed control module
Temperature sensor
Alarms and annunciatorsDigital display
Customer Revalidation:-
Smart system
Restricted application
One time expense

AEIOU Summary:-
AEIOU is to help interpret observations gathered by ethnographic practice in the industry.

Activities are objective-directed sets of actions—paths towards things people want to accomplish. 
Baby bathing
Environments include the entire field where activities take place.

Child care centres
Interactions are between a person and someone else; they are the building blocks of activities. The nature of routine and interactions between people, between people and objects in their environment, and across distances are taken into account.

Care takers
Objects are building blocks of the environment; important elements sometimes put to complex or unintended uses.

Speed control
Obstacle avoidance
PIR sensor
Rain sensor
Temperature sensor
Alarms and annunciatorsMotor driver
Users are those people whose behaviours, preferences and needs are being observed. Who is there? What are their roles and relationships? What are their values and prejudices?
Care takers
Hospital staff

Pendulum motion:
A simple pendulum consists of a point mass suspended on a string or wire that has negligible mass. If the pendulum weight or bob is pulled to a relatively small angle from the vertical and let go, it will swing back and forth at a regular period and frequency. These requirements allow for the equations to be relatively simple.

If the bob is larger, the wire has mass, or the angle is larger, it is called a physical pendulum with complex equations of motion.

Although damping effects from air resistance and friction are a factor, they are considered negligible for the basic equations concerning the frequency or period of the pendulum.

Factors and parameters:
The major factor involved in the equations for calculating the frequency of a simple pendulum is the length of the rod or wire, provided the initial angle or amplitude of the swing is small. The mass or weight of the bob is not a factor in the frequency of the simple pendulum, but the acceleration due to gravity is a factor.

This means that the frequency and period would be different on the Moon versus on the Earth.

Knowing the length of the pendulum, you can determine its frequency. Or, if you want a specific frequency, you can determine the necessary length.

Period equation
The period of the motion for a pendulum is how long it takes to swing back-and-forth, measured in seconds. The equation for the period of a simple pendulum starting at a small angle (?) is:
T = 2??(L/g)
T is the period in seconds (s)
? is the Greek letter pi and is approximately 3.14
? is the square root of what is included in the parentheses
L is the length of the rod or wire in meters or feet
g is the acceleration due to gravity (9.8 m/s² or 32 ft/s² on Earth)
Thus, if L = 2 meters:
T = 2 * 3.14 * ?(2/9.8) = 6.28 * ?(0.204) = 6.28 * 0.4517
T = 2.837 seconds or rounding off a little to T = 2.8 s.

Frequency equation
The frequency of a pendulum is how many back-and-forth swings there are in a second, measured in hertz.

Frequency f is the reciprocal of the period T:
f = 1/T
f = 1/2??(L/g)
The equation can also be rearranged to be:
f = ?(g/L)/2?
Thus, if L = 2 meters,
f = ?(9.8/2)/2*3.14
f = ?(4.9)/6.28 = 2.21/6.28 = 0.353 Hz.

Length of wire
You can find the length of the rod or wire for a given frequency or period.

Solve the equation for L:
f = ?(g/L)/2?
2?f = ?(g/L)
Square both sides of the equation:
4?2f2 = g/L
Solve for L:
L = g/(4?2f2)
For example, the length of a pendulum that would have a frequency of 1 Hz (1 cycle per second) is about 0.25 meters.

Likewise, the length of the wire for a given period is:
T = 2??(L/g)
Square both sides:
T2 = 4?2(L/g)
Solve for L:
L = gT2/4?2
If the pendulum weight or bob of a simple pendulum is pulled to a relatively small angle and let go, it will swing back and forth at a regular frequency. If damping effects from air resistance and friction are negligible, equations concerning the frequency and period of the the pendulum, as well as the length of the string can be calculated.

The period equation is: T = 2??(L/g)
The frequency equation is: f = ?(g/L)/2?
The length equations are: L = g/(4?2f2) and L = gT2/4?2
Acceleration = v / t
Force = m*a
Torque produced = force * radius of the wheel = Power/Speed
Power = 2*3.14*NT / 60
Speed control method:
Speed control means intentional change of the drive speed to a value required for performing the specific work process. Speed control is a different concept from speed regulation where there is natural change in speed due change in load on the shaft. Speed control is either done manually by the operator or by means of some devieces.One of the important features of DC motor is that its speed can be controlled with relative ease. We know that the emf equation of DC motor is given as, N = 60A E / PZØ N = E / kØ where, k = PZ/60A N = V – Ia Ra / kØArmature Resistance Control Method:
This is the most common method employed. Here the controlling resistance is connected directly in series with the supply of the motor as shown in the fig.
The power loss in the control resistance of DC series motor can be neglected because this control method is utilized for a large portion of time for reducing the speed under light load condition. This method of speed control is most economical for constant torque. This method of speed control is employed for DC series motor driving cranes, hoists, trains etc.

Controller, which is the heart of the system, is arduino. Which allows you the easy and efficient control of the system.Power supply, which is 12VDC battery is given to the arduino to operate.

Controlling commands are given through downloading the required program in it, program is to be framed according to the user’s application and system operation. Programming language is easy and very similar to C language.

Various inputs and outputs are connected to the pins of arduino.

Temperature sensor, wet sensor and sound sensor generate anolg signal which needs to be converted into digital form.

Analog to digital converter is used to convert analog signal into the digital form, further it is given to arduino.

PIR sensor is directly connected to arduino as it’s output is already in compatible digital form.

Gear motor, alarms, annunciators, display and messaging system are connected at output side of the arduino.

Thus, according to the input received and program written, output action will be generated and respective output device will be triggered.

Designs for Performance, Safety, and Reliability
Design for performance:
We will increase the performance by using Brushless DC Motor of 12/24/36 V, 800-1000 rpm which will not require replacement of Brushes (Carbon). Apart from these, we will be using rechargeable battery so that the system can frequently be charged whenever required.

Design for reliability:
The prime important factor which is required in any system is reliability. In a sensitive product such as cradle or smart cradle when it is designed to take care of new borns, to make it more robust, we need to increase the reliability which could be done by increasing the comfort and leisure.
Designs for Ergonomics and Aesthetics
The design would consider the ergonomics aspect as well. Besides being highly comfortable and convenient to use, the position and design of control components and equipment will be well within reach. Materials used would feel pleasing to the eyes as well as body of the baby. The monotonous design of cradle would surely be paid attention to and be modified without a significant addition to cost.



Results and Future Scope
The appropriate interfacing of all components according to the circuit diagram gives us hardware circuitry for prototype cradle with smart features. The prototype cradle runs perfectly for monitoring as a Smart cradle. The hardware and software implementation is carried out appropriately. Now, in this segment, all the steps of this work are discussed, and their results are also mentioned. The implemented software is then uploaded on the Arduino board, and the prototype is checked with the help of smart module. The prototype worked successfully with smart modules.
This is to design and develop a smart cradle using automatic continuous monitoring system. The developed cradle is very user-friendly and does not contain any computer system with a cradle for controlling. So it is easy to comprehend and process. It contains two-three modules to control the movement of the cradle according to user commands. If any parent or member cannot be with baby 247, it is very suggestable for them to use this product and leading a stress free life without comrpmosing baby care at any level and adding additional safety at it. Not just this, continuous data logging is useful at child care centres as well as hospitals to keep a record of health condition of baby of secen consecutive days.

Our smart cradle system has proved usefulness to a person in many aspects. Still, there is room for improvement .CHAPTER-5:
Aquib Nawaz, ” Development of smart and baby cradle for hospital use”. Thesis of bachelor of technology, 111BM0010.

“proposal for a smart baby cradle,” Project proposal from Simon Fraser University School of Engineer, vol.3, issue on january 24, 2016.

Misha Goyal, Dilip Kumar “Automatic E-baby cradle swing based on baby cry” International Journal of Computer Applications (0975 – 8887) Volume 71– No.21, June 2013.

Chun-Tang Chao, Chia-Wei Wang, Juing-Shian Chiou, Chi-Jo Wang “An Arduino-Based Resonant Cradle Design with Infant cries recognition” journel of Department of Electrical Engineering, Southern Taiwan University of Science and Technology, issued on august 3, 2015.

Khan Pathan, , Pranjal R. Dandekar2, prof. A.D. Anjikar1, arshad “general idea about smart baby cradle” international journal of innovative computer science & engineering volume 4 issue 1; january-february-2017; page no. 18-20


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