Task 3.1. Anna is giving advice on how to find keywords effectively while reading a document. Use a dictionary to look up the meanings of the following words. Then listen and circle the words you can pick up from the video.
core activities time-saving identical words
grammar synonyms inefficient
main idea adverbs 5Ws and 1 H questions
capitalized or italicized prediction quick note
which paraphrase word byword
Task 3.2. This video mentioned several steps to find keywords and key information effectively in a long and complex document. Watch the video again and match each step and the way to do it.
Step How to do
For the 5-W s, we need to find nouns or compound nouns that First contain information about names, locations, times, or numbers. For
the 1 H, we will look for verbs and adjectives.
Second Scan each paragraph to locate keywords.
Third Find out what kinds of information that we are looking for by using the 5-W and JH questions.
Fourth Underline the keywords and key information that you find in the passage.
Fifth Look for synonyms ( children - kids, singer - artist). We should note that antonym pairs are sometimes used to paraphrase an idea.
Task 3.3. Complete the sentences below. Try to fill in the blanks with the words in the box, then watch the second part of the video to check your answers.
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time- nouns or
verbs and
consummg skimming scannmg compound
adjectives nouns
core
understand 5-W and lH
antonym pairs underlining
activities questions
1. Reading a document, especially a complex document like a patent, can sometimes be very _ _ _ _ _ _ _
2. To read it effectively, you can use techniques like _ _ _ _ _ _ _ and scanning.
3. One of the _ _ _ _ _ _ _ during skimming and scanning is picking out keywords or key information in the passage.
4. The first step we need to do is to find out what kinds of information that we are looking for by using the _ _ _ _ _ _ : What, Why, Where, When, Who, How.
5. For the 5-W s, we need to find - - - that contain information about names, locations, times, or numbers.
6. For the 1 H, we will look for
- - - -
7. We should note that _ _ _ _ _ _ _ are sometimes used to paraphrase an idea.
8. The second step is _ _ _ _ _ _ _ each paragraph to locate keywords.
9. The last step is _ _ _ _ _ _ _ the keywords and key information that you find in the passage.
IO. They are words and sentences that carry specific information that help you to better _ _ _ _ _ _ _ the given document.
Task 3.4. Read the abstract. Choose the best keyword/ key information to fill in the gap in each sentence.
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Abstract-This paper presents the analysis, design, and implementation of a high- performance and cost-effective sensorless control scheme for the extensively used brushless de motors. To decrease cost and increase ease of implementation, the commutation signals are obtained without the neutral motor voltage, multi-stage analog filters, AID converters, or complex digital phase shift ( delay) circuits. In the proposed method, instead of detecting the zero-crossing point of the non-excited motor back electromagnetic force (EMF) or the average motor terminal to neutral voltage, the commutation signals are extracted directly from the specific average line-to-line voltages with simple RC circuits and comparators. In contrast to conventional methods, the neutral voltage is not needed; therefore, the commutation signals are insensitive to the common mode noise. Moreover, the complex phase shift circuit can be eliminated. As a result, the proposed control algorithm can be easily interfaced with the cost-effective commercial Hall effect sensor-based commutation integrated circuits. Due to its inherent low cost, the proposed control algorithm is particularly suitable for cost-sensitive products such as air purifiers, air blowers, cooling fans, and related home appliances. Theoretical analysis and experiments are conducted over a wide operating speed range and different back EMF waveforms to justify the effectiveness of the proposed method.
Source: A New Cost Effective Sensorless Commutation Method for Brushless DC Motors Without Phase Shift Circuit and Neutral Voltage, Cheng-Hu Chen and Ming-Yang Cheng, Member, IEEE, 2007.
1. The _ _ _ _ _ _ _ are obtained without the motor neutral voltage, multi-stage analog filters, AID converters, or the complex digital phase shift ( delay) circuits.
2. In _ _ _ _ _ _ _ _ _ , the commutation signals are extracted directly from the specific average line-to-line voltages.
3. In contrast to conventional methods, the complex phase shift circuit can be
4. The proposed control algorithm can be easily interfaced with the - - - - 5. Theoretical analysis and experiments are conducted over a wide operating speed range
and different back
Task 3.5. Read the statements below and decide if they are true or false. Watch the video again to check your answer. Correct the false statements.
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Statements True/False 1. Finding keywords makes reading a paragraph time-consuming.
2. Keywords are usually nouns and verbs, names, locations, dates and years, and numbers or figures.
3. You can use the SW and 1 H questions to find out what kinds of ã.
information that you are looking for.
4. Only synonym pairs are used to paraphrase an idea.
5. The last step in finding keywords is taking quick notes of what you find in the paragraph.
Task 3.6. Look at the given patent, using what you have learned from the video, and fill the gaps in the sentences below with NO MORE THAN FOUR WORDS.
I. The number of the application is - - - -
2. The term of the patent can be reviewed by - - - -days.
3. According to the list of the inventors, there are _ _ _ _ _ _ _ people who take part in developing this invention.
4. The patent is about the control system of - - - for a rehabilitation apparatus.
5. _ _ _ _ _ _ _ is the Primary Examiner.
6. Tam Nguyen is - - - -
7. There are _ _ _ _ _ _ _ devices in this control system.
8. This patent is assigned to - - - -, Tainan Hsien (TW).
9. The date of the patent is _ _ _ _ _ _ _ 10. The patent was filed on _ _ _ _ _ _ _
53
United States Patent
Tsai et al.
CONTROL SYSTEM OF RESISTING AND ASSISTING FORCE FOR A REHABILITATION APPARATUS Inventors:
(TW);
(TW);
Tainan
Assignee:
Mi-Ching Tsai, Tainan Tien-Chi Chen, Tainan Cheng-Hu Chen, Tainan (TW); Jia-Sheng Hu, (TW); Andy Wu, Tainan Hsien (TW); Joseph Wu, Tainan Hsien (TW)
Tonic Fitness Technology, Inc., Tainan Hsi en (TW) Notice: Subject to any disclaimer, the
term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 171 days.
Appl. No.: 10/252,672 Filed: Sep.24,2002
Int. CI.7 ... A63B 22/06 U.S CI. ... 482/57; 482/5 Field of Search ... 482/ l-9, 51, 52,
482/57-65, 900 References Cited
U.S. PA TENT DOCUMENTS 3,589,193 A* 6/1971 Thornton ... .482/2
(10) Patent No.: US 6,942,603 Bl ( 45) Date of Patent: Sep. 13, 2005
3,848,467 A* 11/1974 Flavell ... 482/4 3,869,121 A* 3/1975 Flavell ... 482/2 5,919,115 A* 7/1999 Horowitz et al...482/
2001/0019985 Al* 9/2001 Reck
* cited by examiner
Prima,y Examiner - Justine R. Yu Assistant Examiner - Tam Nguyen
(74) Attorney, Agent, or Firm-Bacon & Thomas, PLLC
(57) ABSTRACT
A control system of resisting and assisting force for a rehabilitation apparatus includes a motor, a resistance adjustment control device, and a motor output force control device. The motor drives the rotating wheels of the rehabilitation apparatus and controls the rotating wheels to produce resistance and power assisting force. The resistance is designed by imitating the frictional force of different road conditions. The motor output force control device gathers the resistance value preset by the resistance adjustment control device, and the force of a patient pushing or pedaling the rotating wheels and then controls the compensation and the output force of the motor to push the rotating wheels.
When the resistance is adjusted to become increasingly larger and larger by the resistance adjustment device, the force of a patient's hands or legs will gradually increase and finally be able to push or pedal the rotating wheels by himself.
Source: Control .system of resisting and assisting force for a rehabilitation apparatus. Mi- Ching Tsai, Tien-Chi Chen, Cheng-Hu Chen, Jia-Sheng Hu, Andy Wu; Joseph Wu. (2005).
Patent No.: US 6,942,603 Bl.
54
Task 3.7. Use the advice in the video to predict the types of the missing keywords in these sentences (nouns or verbs, names, location, dates and years, numbers or figures). The first one has been done for you.
Sentence
Type of missing keywords
0. There are four claims and _ _ _ _ drawing sheets in the Number patent document.
I . In this document, the 'TW" stands for - - - - 2. Conventional wheelchairs are divided into
categories: hand-pushing wheelchairs and power-driving wheelchairs.
3. The resistance adjustment control device controls the rotating wheels to resistance.
4. This invention is devised to improve the defects and maintain the functions of - - - -and the stationary bike.
5. This U.S patent document was filed on September 24,
Task 3.8. Match the headings below with appropriate paragraphs.
Headings
Mathematical Models of Each Communication State Introduction
Abstract Conclusion
Experimental Evaluation
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A This paper presents the analysis, design, and implementation of a high- performanceãand cost-effective sensorless control scheme for the extensively used brushless deã motors. To decrease cost and increase ease of implementation, the commutation signals are obtained without the neutral motor voltage, multi-stage analog filters, AID converters, or the complex digital phase shift ( delay) circuits.
In the proposed method, instead of detecting the zero-crossing point of the nonexcited motor back eler.;tromagnetic force (EMF) or the average motor terminal to neutral voltage, the commutation signals are extracted directly from the specific average line to line voltages with simple RC circuits and comparators.
In contrast to standard methods, ãthe neutral voltage is not needed; therefore, the commutation signals are insensitive to the common mode noise. Moreover, the complex phase shift circuit can be eliminated. As a result, the proposed control algorithm can be easily interfaced with the cost-effective commercial Hall effect sensor-based commutation integrated circuits. Due to its inherent low cost, the proposed control algorithm is particularly suitable for cost-sensitive products such as air purifiers, air blowers, cooling fans, and related home appliances. Theoretical analysis and experiments are conducted over a wide operating speed range and different back EMF waveforms to justivfy the effectiveness of the proposed method.
B During the last two decades, a lot of research on sensorless control techniques for brushless de motors (BLDCMs) have been conducted. This research can be divided into four categories. 1) Detection of the zero crossing point (ZC~) of the motor terminal to neutral voltage with a. precise phase shift circuit. 2) Back electromagnetic force (EMF) integration method. 3) Sensing of the third harmonic of the back EMF. 4) Detection of freewheeling diode conduction and related extended strategies. Among the various techniques, the back EMF zero crossing detection method is the most popular.
C Fig. 1 shows the equivalent circuit of a BLDCM and the inverter topology.
Fig. 2 illustrates the relationship among the back EME waveform of an ideal BLDCM, the armature current, the commutation signals (Hl-H3 ), and the switching signals (S 1-S6) for the inverter. It can be seen that the fundamental characteristics of a BLDCM during each commutation state is similar to that of a de brush motor.
D Fig. 10 shows the block diagram of the proposed sensorless control method.
The system can be divided into several subblocks, including a velocity command generator, an open loop starting process, a line-to-line voltage based virtual Hall effect signal circuit, an electric commutation table, and a PWM generator. The reference voltage determines the duty ratio for the PWM circuit, and the output speed of the motor is proportional to the duty ratio. The speed command is implemented using a variable resistor, while a simple RC circuit can be added to regulate a required acceleration/deceleration rate to achieve a smooth start. If the reference speed is too low a'nd the reference voltage is not high enough, the
preprogrammed Hall effect signals will be sent to the commutation table sequentially. It is known as the open loop starting procedure, where the BLDCM is operated as a synchronous motor during this process. The open loop starting procedure lasts l .5s to make sure that the rotor will align with the rotating magnetic field.
E Unlike standard back EMF-based sensorless commutation methods which focus on the detection of the ZCP of the motor terminal to neutral voltage, a novel sensorless commutation method based on the average line-to-line voltage is proposed in this study. Both theoretical analysis and experimental results confirm that satisfactory performance can be achieved with the proposed sensorless commutation method. Compared with the conventional solutions, the proposed method has several advantages, including the following.
Elimination of the neutral motor voltage: The neutral voltage is not required in the proposed method, only the three motor terminal voltages need to be detected.
Source: A New Cost Effective Sensorless Commutation Method for Brushless DC Motors Without Phase Shift Circuit and Neutral Voltage, Cheng-Hu Chen and Ming-Yang Cheng, Member, IEEE, 2007.