MINISTRY OF EDUCATION AND TRAINING HANOI NATIONAL UNIVERSITY OF EDUCATION

HOANG VAN TAI

TRAINING AND DEVELOPING ALGORITHMIC THINKING FOR

STUDENTS IN TECHNICAL UNIVERSITIES THROUGH THE

COURSE OF DESCRIPTIVE GEOMETRY

Major: THEORY & METHODOLOGY OF MATHEMATIC EDUCATION

Code: 62 14 01 11

THE SUMMARY OF DOCTORAL DISSERTATION

IN SCIENCE EDUCATION

HA NOI – 2016

The work was completed at:

Department of Mathematics - Hanoi National University of Education

Scientific supervior: Prof. Bui Van Nghi. PhD

Reviewer 1: Assoc. Prof. Trinh Thanh Hai. PhD Thai Nguyen University of Sciences Reviewer 2: Assoc. Prof. Nguyen Xuan Thao. PhD

Hanoi University of Science and Technology

Reviewer 3: Assoc. Prof. Nguyen Anh Tuan. PhD Hanoi National University of Education

The dissertation will be defended before the Council of dissertation assessment

or at: Hanoi National University of Education

At: ............. on ……/……/ 2016

The dissertation can be further referred at:

- National Library of Vietnam

- Library of Hanoi National University of Education

PREAMBLE

1. Reason of study

+ Improvement of learner’s capability: Conference of UNESCO in 2003

presented a report which analyzed clearly significant changes on the need and

demand of knowledge society for students, especially capability of problem

solution and innovation of thought.

+ Role of Descriptive geometry in Technical universities: Helping learners to

present and read drawings, and build up the cooperation and creativity in career.

+ Practical teaching of descriptive geometry shows that: Although this

course is very essential for the profession, its results of teaching and studying are

not high. One of the reasons is the method of teaching and studying, of which

students do not grasp the algorithm in each solution. If an appropriate method is

applied, this weakness will be improved to foster the effectiveness of teaching and

studying.

+ Development of thinking for students: To understand and solve problems

on descriptive geometry, students are not only good at spatial imagination but also

be able to solve problems in a logical and accurate manner and well apply

procedures, basic mathematical problems and other rules of basic procedures and

problems. In addition, students are encougared to propose the alternative ways to

solve mathematical problems by different procedures. All those things create a type

of thought, called Algorithmic Thinking. It is not only necessary for the course of

descriptive geometry but also for the life.

+ Regarding to the relevant researches: There are several researches on the

development of innovative thinking, logical thinking, algorithmic thinking... for

students, but they do not mention about training and developing algorithmic

thinking for students of technical universities.

For the above mentioned reasons, the chosen subject is “Training and

developing algorithmic thinking for students of technical universities though the

course of descriptive geometry”

2. Scientific theory

According to the theoretical and practical base on development of

algorithmic thinking for learners, if during the course of descriptive geometry,

trainers equip students the basic algorithm and create opportunities for them to

propose algorithm as well as improve gradually the level of algorithmic

application, students shall have better learning outcomes and develop their

algorithmic thinking.

3. Goal and mission of study

+ Goal: Proposing methods of training and developing algorithmic thinking

for students of technical universities through the course of descriptive geometry,in order

to help students with better learning results and development of algorithmic thinking.

+ Mission of study: To gain the above goals, the missions include:

(1) Brief introduction on thinking; algorithmic thinking and its role, through

published scientific documents.

(2) Practical investigation on the studying of descriptive geometry and

development of algorithmic thinking for students of technical universities.

(3) Proposing methods of training and developing algorithmic thinking for

students of technical universities through the course of descriptive geometry,in

order to help students with better learning results and development of algorithmic

thinking.

(4) Implementation of pedagogical experiment to evaluate the posibility and

effectiveness of the study

4. Research method

Main methods applied in this thesis are:

+ Theoretical studies (performing tasks (1), (3));

+ Survey and Observation (performing tasks (2), (4));

+ Pedagogical experiment (performing tasks (4);

5. Objects and scope of study

- Object of study is a process of teaching descriptive geometry, training and

developing algorithmic thinking for students of technical universities

- Scope of study: Content, teaching program of the descriptive geometry

course in the technical universities

6. New contribution of the study

+ For theoretical Perspectives

- Generalize the domestic and abroad researches and systematize theoretical

perspectives on algorithm, algorithmic thinking and development of algorithmic

thinking in teaching mathematics.

- Actual situations on training and developing algorithmic thinking for students in

teaching and learning the course of descriptive geometry in technical universities.

- Propose possible and effective solutions for training and developing

algorithmic thinking for students in teaching and learning the course of descriptive

geometry in technical universities

+ For pracical perspectives

- Study results contribute to the innovation and improvement of teaching

and learning quality of descriptive geometry in technical universities

- It is a useful reference document for colleagues and students in technical

universities

7. Defended issues

(1) There are domestic and aboard researches on algorithm, algorithmic

thinking and development of algorithmic thinking in teaching Mathematics,

Informatics, Computer Science, however the issues of training and developing

algorithmic thinking for students in technical universities during the course of

descriptive geometry has not been studied yet.

(2) There are some shortcomings on teaching and learning descriptive

geometry in technical universities that affect the teaching effectiveness and quality

of this course.

(3) Mesures to train and develop the algorithmic thinking for students in

technical universities during the course of descriptive geometry proposed in this

research are possible and effective.

8. Study structure

Besides preamble and conculsion, this thesis consits of 03 chapters.

Chapter 1: Theoretical and practical base

Chapter 2: Measures to train and develop algorithmic thinking for students in

teaching Descriptive geometry

Chapter 3: Pedagogical experiment

Chapter 1

THEORETICAL AND PRACTICAL BASE

1.1. Brief of study

1.1.1. Abroad researches on algorithm and algorithmic thinking

1.1.1.1. For algorithm and teaching algorithm

* Research on the appearance of “algorithm”, Morten Misfeldt (2015)

indicated that: The appearance of the algorithm is associated with the birth of

Mathematics. Evgeniy Semakin Khenner and Igor (2014) stated: The algorithm

describes the sequence of actions (plan), which are performed strictly according to

the instructions to solve the problems in a finite number of steps. According to

Robert J. Sternberg (2000), in daily life, we have learned some algorithms and

ocassionally created it to guide others to do something.

* Research on teaching algorithm, Evgeniy Semakin Khenner and Igor

(2014) stated: The algorithmic teaching has also appeared very early, in the form of

puzzle or fun maths. The book of Levitin Anany (2008) presented many algorithms

and exercises with programming puzzles and algorithms. The book of Thomas H

Cormen (2009) introduced the algorithm 3E, which is used at many universities

worldwide. Marasaeli, Jacob perrenet, Wim M.G. zwaneveld jochems and Bert

(2011) has proposed four abstract levels in the algorithmic thinking of students

corresponding to those of algorithm as follows: (1) Implementation level; (2)

Program level; (3) Object level; and (4) Problem level.

1.1.1.2. For algorithmic thinking

Studies of algorithmic thinking in a foreign country are consistent with the

concept of algorithm in Informatics. According COMAP (Consortium for

Mathematics and Its Applications) (1997): "Algorithmic thinking" is one kind of a

mathematical thinking. The expression of algorithmic thinking is: Application of

algorithm; Development of algorithm; Analysis of algorithm; Noting the problem

without algorithmic solution. According to Gerald and Julia Moschitz Futschek

(2011), algorithmic thinking is an important capability in Informatics that can be

separated with the learning of computer programming.

1.1.2. Domestic researches

1.1.2.1. For algorithm and teaching algorithm

In essence, each calculation, rules for calculation and solving the equations

... are algorithm. In Geometry, there are some algorithms such as: drawing with a

ruler and compass. At university, algorithms are also found, for example:

calculating the definite, higer equatations, matrix inversion and determinant…

Nguyen Ba Kim and Vu Duong Thuy (1992) defined the algorithm as followings:

“The algorithm is considered as a descriptive rule of the clearly accurate

instructions helps people (or machines) to perform a series of actions with the aim

of achieving its propsed goals or solving a certain problem. It is not an exact

definition but merely a statement which helps us to imagine the concept of

algorithm intuitively”. Bùi Văn Nghị (1996) used the definition on algorithm of the

two above authors and added the concept “algorithmic procedure”. Vương Dương

Minh (1996) studied “Development of algorithmic thinking for students while

teaching numeration system in high schools". The author has given a definition of

algorithm as follows: "Algorithm is an accurate and simple rule of limited numbers

of primary actions following a definite order specified on the object so that we will

obtain desired results after perporming that procedure”. Some authors also

identified the two concepts, "algorithm" and "algorithm" such as works of Chu

Cẩm Thơ (2015), Nguyễn Chí Trung (2015)

1.1.2.2. For algorithmic thinking and development of algorithmic thinking

There are domestic researches on development of algorithmic thinking for

students. For instance, a research of Vũ Quốc Chung (1995) on fostering capacities

of thinking for students in the final grade of primary school; a work of Nguyễn

Thái Hòe (1997) on training the thinking for students via mathematic exercises;

works of Nguyễn Đình Hùng (1996), Nguyễn Văn Thuận (2004) on developing

logical thinking for students; awork of Tôn Thân (1995), Trần Luận (1996) on

fostering creative thinking for students.

Among the domestic researches on algorithm and algorithmic thinking, it

can be counted for Trần Thúc Trình (1975), Nguyễn Bá Kim (1992, 2011, 2015),

Vương Dương Minh (1996) và Bùi Văn Nghị (1996).

Nguyen Ba Kim (2011) suggested that algorithmic thinking is shown in the

following activities: (i) Implementing the activities following the certain order in

accordance with a provided algorithm; (ii) Anlalyzing an activity based on

performance of its components in a certain order; (iii) Describing exactly the

process of conducting an activity; (iv) Generalizing an activity on a group of

objects from an activity; (v) Comparing different methods to perform the same

work in order to find the optimal solution.

Based on the research results on algorithm and algorithmic thinking, the

conclusion is summarized as follows:

- The domestic and abroad authors agree with the concept of algorithm in

Computer Science and Informatics. However, the researchers in mathematics

education in domestic schools only concern about the concept of algorithm in

intuitive manner. Meanwhile, researchers in Computer Science and Informatics can

not stop at this limit, especially when they need to prove the non-existence of an

algorithm to solve a problem; an algorithm based on the Turing machine or

recursive function are required.

- It is nesscessary to distinguish algorithm in science from algorithm in daily

life. If a solution process does not consit of specific and clear actions to gain a good

result, it only is considered an algorithmic-like process

- Many abroad authors assumed “algorithmic thinking” in the meaning of

strict in Computer Science and Informatics; some domestic authors considered

algorithmic thinking as an algorithmic-like process.

1.2. Concepts on algorithm and algorithmic thinking in this thesis

1.2.1. Algorithmic concepts

In this thesis, we assume: The algorithm is considered as a descriptive rule of

the clearly accurate instructions helps people (or machines) to perform a series of

actions with the aim of achieving its propsed goals or solving a certain problem.

1.2.2. Algorithmic thinking concepts

We assume that: Thinking is a cogitative way to perceive things,

phenomena, and the natural and social relationships and human that is expressed

through notion, judgments, and inference. These concepts do not concentrate on the

psychological nature of the cognitive process, but appearance (more intuitive) on the

thinking. Algorithmic thinking is applied to solve problems through not only algorithm

but also “algorithmic process" or “algorithmic-like process".

1.3. Descriptive geometry course in technical universities

1.3.1. Brief history of descriptive geometry

Descriptive geometry was introduced by Gaspard Monge (1746-1818) and

used in French education system since Century XVIII. In Vietnam, since the year

60s of the previous century, when the first universities was established, descriptive

geometry was taught officially in Univerity of Technology and Science.

1.3.2. Brief introduction of descriptive geometry

Descriptive geometry is the branch of geometry which allows the

representation of three-dimensional objects in two dimensions by using a specific

set of procedures. This course equips the leaners knowledge and skills to

understand and draw the technical drawings. Knowledge of descriptive geometry is

basic, compulsory and minimum for a student in technical universities.

In descriptive geometry, each point A in the space is represented by only a

pair of projection (A1, A2) on two planes of perpendicular projection. And vice

versa, each pair of projection (A1, A2) on two planes of perpendicular projetions

identifies point A in space. Thus the representation of spatial projection on two

planes of perpendicular projections shall totally define the size and shape of

geometrical figures. All problems of descriptive geometry are problems of the

formatting image; every problem has only one answer. Hence, application of

algorithm to solve the problems of descriptive geometry can be considered.

1.3.3. The expression , the level of algorithmic thinking of students and

the opportunity to develop algorithmic thinking in teaching descriptive

geometry at the Technical University of block

1.3.3.1. The expression, the level of algorithmic thinking of students

expressed through descriptive geometry module

Thinking algorithm University students Technical block manifested in

descriptive geometry module through the ascending levels of the following:

i) To comply with the basic algorithm known in the course of payment;

ii) Imagine , performing the entire process of solving the problem, solve the

problem according to the block diagram, process simulation or language, or

algorithms written into the program;

iii) Know how to apply these algorithms known during problem solving;

iv) May participate in the proposal, design algorithms in the process of

accounting;

v) Can select the optimal algorithm in multiple algorithms and solve a

problem.

1.3.3.2. Opportunities to develop algorithmic thinking in teaching

descriptive geometry at the Technical University of block

- Opportunities for the content knowledge in module

- Chance of cognitive abilities of students

- Opportunity to organize teaching methods

1.4. Practical Situation of teaching and learning descriptive geometry in

technical universities

1.4.1. Advantages and disadvantages of students in learning descriptive

geometry

* Advantage: Basic knowledge of descriptive geometry is based on basic

knowledge of Euclidean geometry which was taught in high schools. Some

drawing softwares such as AutoCad, Cabri, GSP… can be used in teaching and

learning descriptive geometry

* Disadvantage: When studying the descriptive geometry, the learners are

required to have spatial imagination and logically reasoning ability.

1.4.2. Investigating practical situation of teaching and learning descriptive

geometry in technical universities

We have designed and used Questionnaire on teaching and learning the descriptive geometry for 250 2nd year students - term 57 and 58 at two educational

institutions of the University of Mining and Geology (Hanoi and Vung Tau) in

September (one month after learning the course of descriptive geometry) in 2013

and 2014.

Results show that: When start learning the descriptive geometry, most of

students (80%) reported that this is a difficult subject, the rest 20% stated that this

subject is very difficult. Many reasons were reported by students as follows. For

10% of students, the reason is students must understand thoroughly the knowlgde

in high schools; 25% assumed that they has not found a proper learning methods, in

which 15% for teacher’s teaching methods and 10% for timing isues; for 40%

thought that it is difficult because of requirement of good spatial imagination.

Therefore, most of students are not interested in this subject; 20% feel normal and

only 15% are excited with that.

In conclusion, it is propably stated that the descriptive geometry is quite

abstract and difficult for students in technical, civil engineering and architectural

universities. Also teachers has not concerned appropriately about formity and

development of algorithmic process for students, leading to low effectiveness of

teaching

1.5. Conclusion of Chapter 1

In the technical universities, descriptive geometry equips students the basic

knowledge to understand and draw technical drawings, also contributes to develop

spatial imagination, algorithmic thinking, creative thinking for students, engineers,

architects, industrial art painter during their work. Therefore, teaching the course of

descriptive geometry in the direction of training and development of algorthmic

thinking for students of technical universities are justified.

Chapter 2

MEASURES TO TRAIN AND DEVELOP ALGORITHMIC THINKING FOR

STUDENTS IN TEACHING DISCRIPTIVE GEOMETRY

2.1. Measures building orientation

(1) Orders of measures should be suitable to procedures of forming and

developing algorithmic thinking for students

(2) Measures proposed should be suitable to students and perception

process of leaners.

(3) Measures should be feasible and effective

(4) Measures aim to innovate the present methods of teaching discriptive

geometry

2.2. Basic definitions and knowledge in descriptive geometry

2.3. Methods to train and develop algorithmic thinking for students in

teaching descriptive geometry

2.3.1. Method 1: select some basic algorithmics and train stydents to well

apply them into basic maths in Descriptive geometry.

2.3.1.1. Method base: base on the learners; base on the difficulty of

descriptive geometry course; base on the content of descriptive geometry.

2.3.1.2. Method implementation approach

First and foremost, we need to select some basic algorithmics.Those are

procedures that problems in Descriptive Geometry will be inferred to. If students

are trained to be skillfull in those basic Algorithmics, there are more chances for

them to solve simple descriptive geometry problems.

We selected the following basic algorithmics:

- Determine a point on a line;

- Determine the intersection point of a common line and the projected planes

(trace of line);

- Determine the vertical projected plane (projected by) (P) contains a given

line a (a1, a2);

- Determine the true magnitude of a line segment;

- Define a line perpendicular to the plane.

Specifically,

Basic algorithmics 1: Determine a point on a line

In descriptive geometry, there are some common problems as follows:

determine the intersection point of two intersected lines, determine a point of a

given triangle or a given tetrahedron, and identify a point in a generatrix of a

cylindrical or conical surface. These problems are all defined as determining a

point on a line. Hence, we decided that the algorithmics to determine a point of a

straight line is a basic algorithmics.

Situation 1: line d is a normal line (not perpendicular to the axis x,

algorithmics to identify A in d as follows:

Step 1: Identify A1 d1

Step 2: Identify A2 d2 so that A1A2 x

Situation 2: line d is a special line (which is perpendicular to axis x, also

called an edge line) – determined by two points B (B1, B2) and C (C1, C2),

algorithmics identifies point A on line d as follows

Step 1: determine A1 B1C1

Step 2: determine A2 B1C2 so that A1A2 x, single ratio of a three-point set

B1,C1,A1 equals to , single ratio of a three-point set B2,C2,A2: (B1C1, A1) =

is a single ratio of a three-point set B, C, A on a (B2C2,A2). Therein (BC,A) =

straight line.

From this basic algorithmics, we can infer the following algorithmics to

solve basic problems:

Problem 1.1. Determine a point on plane (ABC): given point M on plane

(ABC) = (A1B1C1, A2B2C2). Determine the projection

by M2 when vertical projection M1 is known (Figure 1)

Algorithms for solving the problem as follows:

Step 1: Determine I1 = B1C1 ∩ A1M1;

Step 2: Apply basic algorithm 1 to identify I2;

Step 3: Apply basic algorithm 1 to identify M2;

(If B1C1//A1M1, we identify I1 = B1C1 ∩ A1M1

and follow the same procedure)

Figure 1

Problem 1.2. Determine a point on a plane of

tetrahedron ABCD.

Problem 1.3. Given a quadrilateral ABCD  (P) = (V1P, V2P), known

vertical projection A1B1C1D1, determine projection by A2B2C2D2.

Projection 1.4. Given a plane (ABC), make line b of the plane with given height

x

Problem 1.5. Determine a point on a cone of revolution

Algorithmics 2: determine intersection point of a line and projected planes.

Given line a (a1, a2), determine intersection point M of

a and (P1) and intersection point N of a and (P2).

Algorithmic steps to solve the problem as follows:

If a straight line is not parallel to the plane of

projection, the procedure for determining trace a

following

Figure 2

Step 1: Determine M2 = a2 ∩ x;

Step 2: Apply basic algorithm 1 to identify M1;

Step 3: Determine N1 = a1 ∩ x;

Step 4: Apply basic algorithm 1 to identify N2.

If a is frontal (a2 // x), the intersection N of a and (P2) is identified by B1 and

B2 above; If a is surface (a1 // x), the intersection M of a and (P1) is identified by

B3 and B4 above

Use the basic algorithmics 2, we can solve the basic problems on finding

traces of a plain.

Problem 1.6. Given (P) determined by 2 intersected lines a (a1,a2), b (b1,b2),

a and b do not parellel to axis x. Find traces of plane (P).

Problem 1.7 Determine the intersection of the vertical projection plane (P)=

(V1P,V2P) with plane (Q) = (a//b)

Problem 1.8 Determine the intersection of the vertical projection plane (P)=

(V1P,V2P) with plane (Q) = (V1Q,V2Q).

Basic algorithmics 3: Determine the vertical projection plane (projection

by) containing a given line

Basic algorithmics 4: indentify the real magnitude of a segment

Basic algorithmics 5: identify a line perpendicular to a plane

Problem 1.9. Identify distance from point A (A1, A2) to plane (P) in

following cases: (P) = (V1P, V2P);b) (P) = (a x b)

Problem 1.10. Identify distance from A to line d

2.3.2. Method 2: Train the students to use some mehods to demonstrate

algorithmics in teaching descriptive geometry.

2.3.2.1. Method base: base on the significance of the block diagram; base on

teaching method of algorithmics.

2.3.2.2. How to implement the method

+ When teaching Descriptive Geometry, teachers need to combine analysis

to solve problems with algorithmic demonstration. This combination will clarify

the analysis and the students also can learn about algorithmic demonstration.

Lecturers can select some cases and activities for modeling, and then ask students

to practice some similar cases.

Example 2.3.1: when teaching about second basic algorithmics, besides this oral

description, we can demonstrate algorithmics by simulation language as follows:

Beginning:

If a1 // x

Then a a ∩ P2 = ϕ, a ∩ P1 = M, with M2 = x ∩ a2, M1M2 x;

x And if a1

Then consider a2

If a2//x

then a ∩ P1 = ϕ, a ∩ P2 = N so N1 = x ∩ a1, N1N2 x

x

if a2

then a ∩ P1 = M so M2 = x ∩ a2, N1= a1 x, M1M2 x, N1N2 x

ending.

Schematic illustration (Figure 3):

Figure 3

+ Instruct students to practice some similar examples

Example 2.3.2. Demonstrate algorithmics by block diagram to identify the

line perpendicular to plane

Schematic illustraction: (Figure 4)

(a) (b) (c)

Figure 4

2.3.3. Method 3: create opportunites for students to joind hands in

building and propose some algorithmics in solving some problems in descriptive

geometry

2.3.3.1. Method bases: Base on process of training and develop algorithmic

thinking mentioned in orientation 1 in chapter 2; base on plate-tectonic theory and

operational perspective; base on the needs of developing capacity of leaners; base

on memory effectiveness; base on course contents;

2.3.3.2. How to implement the method

(1) Select the problems demonstrates many cases and give chance for

leaners to cooperate, discuss, propose algorithmic solution for each case.

Example 3: Relative position of two distinguished lines, 3 situations:

Situation 1: two normal lines;

Situation 2: one normal line and one special line

Situation 3: two special lines: with two normal lines, 3 possibilities for two

projections of the same name: intersected by two, parallel by two, an intersected

pair and a parallel pair. When two projection pairs of the same name intersect by

two: whether two intersection points lie on the same alignment line.

The same possibility happens for the rest of situations.

Hence, a discussion among students can be organized: what is the relative

position of each following schemetic? (Figure 5)

Figure 5

2.3.4. Method 4: Apply different algorithmics in descriptive geometry and

practical application

2.3.4.1. Method base

+ Base on objectives of the descriptive geometry course of technical

universities;

+ Base on the orientation of developing capacity for learners;

2.3.4.2. How to implement the method

First approach: train the students to identify the intersection of two surfaces

in line with 3 level of increasing difficulty: interface of 02 polyhedrons; interface of

01 polyhedron and 01 curved surface; interface of 02 curved surfaces; intersection

of 03 surfaces

We need to combine several times of following algorithmics:

- Algorithmics to identify intersection of two planes;

- Algorithmics to identify the intersection point of line and plane;

Moreover, we need to use auxiliary planes and identify intersection points of

both planes on each auxiliary plane. The problem now is to identify the intersection

of lines on the auxiliary plane. For example: find the intersection of of two

cylindrical surfaces: let (R) parallel to generatrix of two cylinders; find intersection

of two conical surfaces: let (R) go through conical peak and parallel to the

generatrix of the cylindrical surface; find the intersection of two conical surfaces:

let (R) contain line connecting two peaks of both cones….

Example 4: Identify the intersection between an oblique prism with base

∆DEF and a cone S.ABC in the schematic in Figure 6a

a b

Figure 6

Possible steps to identify the intersection of these two faces:

- Identify the auxiliary cross section of vertical projection , δ,… to find the

intersection of sides d, e, f of the prism and the cone, we have peaks 1, 2, 3, 4.

- Identify the auxiliary cross section of vertical projection by ,… to find the

intersection of sides of cone with prism, we have peaks 5, 6. The result is the

schematic as in figure 6b.

* For the intersection of two curved surfaces: we can devide students into

groups for researching of each following pairs:

(1) Identify intersection of 2 conical faces which share the same base;

(2) Identify intersection of a conical face with peak S and a cylindrical face

which share the same base;

(3) Identify intersection of two conical faces which do not share the same

base;;

(4) Identify the intersection of two cylindrical faces share the same base;

(5) Identify the intersection of a conical face and a spherical face;

(6) Identify intersection of a cylindrical face and a spherical face.

Second approach: Combination between Descriptive Geometry and

Technical drawing.

Technical Drawing Module is considered a direct application of the

knowledge of Descriptive Geometry. In Technical Drawing, students must reach

the following requirements: from a drawing, students have to imagazine and

present the objects on the axonometric view. Descriptive geometry will help us

overcome the difficulties in visualizing the object and know the intersection of the

two surfaces in the space from given drawings. Therefore, during Descriptive

geometry, teachers need to train students to be familiar with the drawings and

understand the design idea of the drawing.

Example 5. Given 03 objects as Figure 8. Identify the intersection of surfaces?

Present those intersections on multiview drawing.

Figure 8

Third approach: Assign each group of students to perform the assignments:

Researching an architectal work or creating an architectual form based on the

intersection of 02 surfaces.

Example 6. Design "pluripotent" bottle cap which can cover three types of

bottles as follows: A round cap with diameter of a; A square cap with a side of a; A

isosceles triangle cap with the bottom side of a and its height of a. (Figure 9)

Figure 9

The needed cap should be the common part of three circular cylinders with

vertical sections respectively in shape of the three above mentioned bottles. The

problem will be determined to identify the intersection of three cylinder surfaces

(three surfaces of these three cylinders).

2.4. Conclusion of Chapter 2

Our solution is to focus on training algorithms in soving the problems of

descriptive geomestry for students. This solution has helped students to learn this

course more efficiently and develop their algorithmic thinking. We asume that the

initial actions should be noted to form, train amd develop gradually algorithmic

thinking for students. Firstly, students need to become familiar with the basic

algorithm (foundation, core) and practice to master that through basic problems

(Method 1); training them some forms of algorithmic represetation (Method 2);

Then they can propose their own algorithims in a simple way (Method 3). Finally,

the measure to help them to combine and apply many algorithms effectively

(Method 4).

Chapter 3

PEDAGOGICAL EXPERIMENT

3.1. Pedagogical experiment purposes, methods and organization

3.1.1. Purposes of pedagogical experiment

Pedagogical experiment aims at assessing the feasibility and effectiveness

of measures in training and developing algorithmic thinking for technology

students through the module of Descriptive Geometry proposed in the thesis.

3.1.2. Pedagogical experiment methods and organization

Pedagogical experiment is conducted in two phases, with 2 units per phase:

Phase 1: Unit 1 to be taught from September 9 to 14, 2013, Unit 1 from

September 23 to 28, 2013, at the Hanoi campus of University of Mining and

Geology. The class chosen for pedagogical experiment was K58 Oil Refinery

(with 60 students), taught by Lecturer Hoang Van Tai, in 2 curriculums presented

in Section 3.2 of the thesis; whilst the control class was K58 Engineering Geology

(with 60 students) taught by Lecturer Le Thi Thanh Hang, in self-written

curriculum. Unit 1 –“Determining traces of a plane" practice (tasks on position

estimates, including 2 periods); Unit 2 - "Distance" practice (tasks on trigonometry

including 2 periods).

Phase 2: Unit 1 to be taught from September 8 to 13, 2013, Unit 1 from

September 22 to 27, 2013, at the Vung Tau campus of University of Mining and

Geology. The class chosen for pedagogical experiment was K59 Drilling and

Production (with 53 students), taught by Lecturer Hoang Van Tai, in 2 curriculums

presented in Section 3.2 of the thesis; whilst the control class was K59 Mining

Geodesy (with 51 students) taught by Lecturer Vu Huu Tuyen, in self-written

curriculum. The 2 units were identical as in Phase 1. The lecturers of pedagogical

experiment classes and control classes teach the same subject, of approximately the

same age, seniority and pedagogic capacity (as identified by the Department)

3.1.3. Pedagogical experiment preparation

Step 1: Preparing lesson plans and questionnaire for observers and students

on experimental lessons

Step 2: Department discussion, aiming to an agreement on experiemental

teaching purpose, organization, content, method and result assessment, and on the

test (questions, pedagogical goals, scale and answer key);

Step 3: Conducting experimental lessons, collecting comments of observers

and students through the questionnaire.

Step 4: 45-minute test after each lesson for the experimental class and

control class occured at the same time, with the same questions and answer keys

Step 5: Pedagogical experiment results processing

3.1.4. Pedagogical experiment hypothesis

Students would have a better understanding of the topics, distributing to the

development of their algorithmic thinking if taught to the curriculum based on

training methods for algorithmic thinking development as proprosed in Chapter II

of the thesis.

3.2. Pedagogical experiment content

(Experimental lesson plans attached in the thesis)

3.3. Pedagogical experiment result assessment

+ Qualitative Assessment: by questionnaires done by 226 students

participating in the lessons and 20 observers

+ Quantitative Assessment: by two tests after each experimental lesson:

classifying, creating table charts, bar charts and statistical hypothesis testing.

For instance, the comparation of post-experimental result of the 1st test of the 1st phase between the experimental class and the control class is demonstrated in

the chart below:

Chart 1. Comparation of the 1st test result

3.4. Summary of Chapter III

Pedagogical experiment was conducted in two phases, each one of them took

place at the campus of University of Mining and Geology (in Hanoi and Vung

Tau), with two classes taught by pedagogical experiment and two control classes.

Pedagogical experiment results are assessed by tests with participation of

240 students (both times) and 20 observers. Despite the fact that the pedagogical

experiment was conducted in a small scale, the results have shown that:

- The feasibility and effectiveness of pedagogical experiment plans were

reassured;

- Dual goals obtained in experimental lessons: The students having a better

understanding of lesson contents and contributing to the development of their

algorithmic thinking.

CONCLUSIONS AND RECOMMENDATIONS

CONCLUSION

The thesis has the following results:

(1). Briefly introduce domestic and abroad research results on teaching

algorithm and development of algorithmic thinking for learners;

(2). Present the sientific base of development of algorithmic thinking for

students in technical universities through teaching the descriptive geometry:

Conception of algorithm, algorithmic thinking, demand and means for development

of algorithmic thinking for learners.

(3) Propose 04 methods to train and develop the algorithmic thinking based

on required procedures and goals of the descriptive geometry course for students in

technical universities.

(4) Carry out the pedagogical experiment at two educational facilities of

University of Mining and Geology (Hanoi and Vung Tau).

REQUEST

Oriented curriculum development , capacity -oriented learners, so it takes

time for students to apply what they have learned into practice career , solve

problems arising from the practice . Thus the increase in the length module ,

increasing the time and enhance the practice of occupational activity is an

important issue and needed. Opinion, should have at least 4 credits of this module

can be reduced by difficulties in teaching and learning modules for both teachers

and students.

PUBLISHED WORKS OF THE AUTHOR RELATING

TO THE THESIS

1. Hoang Van Tai – Vu Huu Tuyen (2012), Designing situations of teaching

the procedure defined the poit projection via “Trigonometry problem” in

Desriptive Geometry, Journal of Education Science, ISN 0868 – 3662, No. 84,

page 28 – 30.

2. Hoang Van Tai (2014), Development of algorithmic thinking for students

through teaching Descriptive Geometry, Journal of Science, ISN 0868 – 3719,

Volume 59, page 121 – 128.

3. Hoang Van Tai – Nguyen Thi Huong Lan (2015), Algorithmic thinking in

problems defined the trace of plane (Descriptive Geometry), Journal of Science,

ISN 2354 – 0753, Special edition in 10/2015, page 123 – 125.

4. Hoang Van Tai – Nguyen Thi Huong Lan (2015), Cooperative teaching

“Defining the intersection line of 02 quadric planes” in Descriptive Geometry at

University of Mining and Geology, Journal of Education, ISN 2354 – 0753, Special

edition in 10/2015, page 126 – 128.

5. Hoang Van Tai (2016), Algorithm development thinking for students of

technical universities through block modules descriptive geometry, Journal of

Education Science, ISN 0868 – 3662, Special edition in 01/2016, page 45 – 47.

6. Hoang Van Tai (2016), Algorithm development thinking and problem-

solving capacity for students in teaching descriptive geometry, Journal of Science,

ISN 2354 – 0753, No. 377, page 47 – 49.