Báo cáo " ENVIRONMENTAL EDUCATION BY PROBLEM BASED LEARNING METHOD (PBL) - BENEFITS AND REMAINING ISSUES - APPLY IN TEACHING CLEANER PRODUCTION SUBJECT IN HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY " pdf

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ENVIRONMENTAL EDUCATION BY PROBLEM BASED LEARNING
METHOD (PBL) - BENEFITS AND REMAINING ISSUES - APPLY IN
TEACHING CLEANER PRODUCTION SUBJECT IN HO CHI MINH CITY
UNIVERSITY OF TECHNOLOGY

Vu Hai Yen
Department of Environment and Biotechnology,
Ho Chi Minh City University of Technology, Vietnam

TÓM TẮT
―Ngƣời ta chỉ bảo vệ những gì mà họ yêu, chỉ yêu những gì mà họ hiểu, chỉ hiểu
những gì mà họ đƣợc học‖. đó là một câu châm ngôn khôn ngoan trong lĩnh vực giáo
dục, đặc biệt là trong lĩnh vực giáo dục môi trƣờng. Cốt lõi của vấn đề truyền thông,
giáo dục ý thức bảo vệ môi trƣờng của sinh viên, học sinh đều nằm ở việc giáo dục tình
yêu, lòng hăng hái, và trách nhiệm của giới trẻ đối với cuộc sống.
Trong thời gian vừa qua, giáo dục đại học đƣợc xem nhƣ những kiến thức ở tầm
vĩ mô, xa rời thực tiễn, vì thế mà sinh viên khó có thể áp dụng vào thực tiễn. Vài năm
trở lại đây, giảng dạy đại học bằng phƣơng pháp đặt vấn đề (Problem Based Learning)
thƣờng đƣợc nhắc tới nhƣ một phƣơng pháp giáo dục kiểu mới đem lại nhiều hiệu quả.
Phƣơng pháp này phát huy tính tích cực, chủ động trong học tập, ngƣời học đƣợc rèn
luyện các kỹ năng cần thiết, sớm tiếp cận những vấn đề thực tiễn và biết cách tổ chức
vấn đề, bài học đồng thời đƣợc nhớ sâu hơn. Phƣơng pháp còn giúp giảng viên không
ngừng vƣơn lên để học hỏi không ngừng. Phƣơng pháp đã giúp giảng dạy thành công
các môn học kỹ thuật vốn khô khan từ trƣớc đến nay, trong đó có các bộ môn Kỹ thuật
Môi Trƣờng. Tuy nhiên, ngoài những lợi ích dễ dàng nhận thấy, phƣơng pháp này vẫn
có những bất cập nhất định. Nội dung bài tham luận là tổng quát về những thuận lợi và
khó khăn trong công việc giảng dạy các môn học môi trƣờng.
Trong các môn học trong chuyên ngành Môi Trƣờng, môn học Công Nghệ Sản

Xuất Sạch Hơn là môn học đòi hỏi kiến thức tổng hợp từ nhiều lĩnh vực, kiến thức
chuyên môn nhiều nhất. Môn học này bắt đầu đƣợc giảng dạy trong khoảng 10 năm trở
lại đây. Do vậy, áp dụng PBL vào công tác giảng dạy môn học Công Nghệ Sản Xuất
Sạch Hơn là điều thực sự cần thiết. Nhƣng áp dụng nó nhƣ thế nào, những thuận lợi và
khó khăn nào sẽ gặp phải khi sử dụng phƣơng pháp này? Bài tham luận trình bày các
lƣu ý cần áp dụng trong việc giảng dạy môn học Công Nghệ Sản Xuất Sạch Hơn tại các
trƣờng Đại Học trong Thành phố Hồ Chí Minh.

INTRODUCTION
In recent times, education is seen as the knowledge at the macro level, far from reality, so that
students can not be applied to practice. Few years, teaching method question (Problem Based
Learning) is often referred to as a new kind of educational methods bring more efficiency. This
method of promoting a positive, active learning, students are trained to the necessary skills, early
access to practical issues and how to organize the issues, lessons at the same time is remembered
more in-depth . The method also helps teachers constantly striving to learn continuously. The
method has successfully helped teach technical subjects which hitherto sterile, including the
Environmental Engineering department. However, in addition to the benefits of easy to see, this
method still has certain shortcomings.
In the specialized course work in Environmental field, Cleaner Production Technology is a
subject requires knowledge from multiple domains, the most expertise. This course is taught
starting in about 10 years. Therefore, the application of PBL in teaching subject Cleaner Production
Technology is indeed necessary. But how to apply it, the advantages and disadvantages will be
encountered when using this method?

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RESEARCH PURPOSE
Topics focus on the issues as follows:
-Teaching Method question: purpose, methods, benefits, meaning, scope, advantages and

difficulties in teaching this method.
- Apply in teaching the subject Cleaner Production Technology: subject characteristics, by
applying the teaching methods into question how teaching this course.
- Finding on the advantages and disadvantages when using this method to teach Cleaner
Production Technology.
RESEARCH CONTENTS
The study focused on two directions as follows:
+ Learn teaching methods question (Problem based learning): definition, purpose, methods,
benefits, meaning, scope, advantages and difficulties in teaching this method.
+ To apply these teaching methods in teaching subjects Cleaner Production Technology:
-Understanding of the course requirements in each field of study, course duration for
-Select-level teaching
-From the number of students, selected teaching methods
-Distribution of time, select the appropriate topics for student
-Lessons learned from practical

TEACHING METHODS
Definitions
Teaching problem-based learning (PBL: Problem based learning) is an overall approach to
education, at both angles curriculum learning process: curriculum includes selected issues and
carefully designed kidneys to help the school to receive knowledge is a critical way, strengthen
problem-solving skills, self-study and group work skills, the learning process as systematic problem
solving process or may face challenges in life. Learning problem is based on teaching methods to
help students receive the knowledge and skills through a learning process is based on the questions,
problems and practical tasks that have been built up.
Objectives
- Awareness: helping students have the opportunity to grasp the breadth of knowledge.
- About skills: helping learners to develop reading ability, scientific research skills, problem-
solving skills, social skills such as teamwork, presentations, debates, negotiations,
- On attitude: helps students feel close and loved the subject and learn, see the value of group

activities for themselves.
The characteristics of teaching methods based on problem
Background center of learning and teaching activities
Instead information is presented from low to high, students will only have access to a problem
to be explained once they are fully equipped with the necessary knowledge. Learners have access to
immediate problems in the early stages of a teaching unit. The problem may be a natural
phenomenon or an event / situation was, is or may in fact occur and contain things to be explained.
The self-exploration study to determine the source of information to help solve problems
On the basis of issues raised, the learner must actively search for relevant information to solve
problems. In other words, the students almost have to equip yourself with the "theory" in order to
have sufficient knowledge to approach and solve problems.
Group discussions are the core activities
Through discussion in small groups, students share information and resources together to
form hypotheses to help solve the problem, and hypothesis testing concluded.
The role of teacher support nature
Lecturer‘s role orientation (pointing out the need to explain the problem), assistance (only
source of information, questions, ), assessment (testing hypotheses and conclusions of study),
codified knowledge, generalized conclusions.
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Advantages and disadvantages of teaching methods based on problem
Advantages
-To promote positive and active learning.
- The school trained the necessary skills: practice / reading skills, scientific methods of
thinking, scientific debate, collective work
- The lesson has been wide acceptance has deep, long stored in the memory study.
- Require teacher constantly rising.
Disadvantages
- Difficult to apply in the subject is highly abstract: This method does not result in the same

for all subjects, although it can be widely applied. In fact the subject close to reality as much to
build, the more likely problem, and thus applicability of the method is higher.
- Difficult to apply to large classes: Classes are more crowded more and more small groups so
that the organization, management will become more complex. A teacher is difficult to monitor and
guide the discussion for a dozen study groups. In this case, the role of teaching assistants will be
essential.

FEATURES OF THE SUBJECT OF CLEANER PRODUCTION (CP)
Objectives of the course
-Knowledge: The objective of the course is to introduce students method, a new approach to
prevention has just had its high environmental pollution. This approach not only helps
manufacturers and service providers to reduce the amount and toxicity of waste in the production
process again just to bring high economic efficiency.
- Skills: implementing the cleaner production projects for the manufacturing industry.
- Attitudes, attendance: need serious learning attitude, diligence. Industrial environments
always require strict working style, and progressive responsibility.
Course Content
The program teaches cleaner is designed to give students the scientific environment with basic
knowledge on cleaner production technology, skills implementation of cleaner production, the
technical solutions to reduce waste and toxic calculation of waste at source and integrate the
implementation of energy efficiency in the CP, the attitude required when implementing cleaner
production.
+ Part 1: Introduction of cleaner production: a) Overview of environmental protection; b)
The concept: cleaner production; Productivity Ecology, Pollution Prevention, Clean Technology; c )
The similarities and differences in concepts, approaches, d) The purpose and significance of the
application of cleaner production; f) Difficulties and advantages in the application of cleaner
production in Vietnam and the world; f) practical application of cleaner production in HCMC City
from 1996 to present.
+ Part 2: implementation of cleaner production techniques and tasks or steps in the
implementation of cleaner production: a) Establish CP group; b) List the processes; c) Determine

the fuel consumption and selected key center audit; d) Develop flow charts for key audit; e)
Calculate the balance of raw materials (material balance): f) Determination of loss due to waste
money in production; g ) Analyze and determine the cause of emissions, waste ; h) Proposals and
selection of CP opportunities; i) Screening and feasibility analysis of opportunities; j) Options and
Opportunities implementation plan; k) maintaining focus and selecting a new auditor; l) Objectives
and significance of the combined use of cleaner energy efficiency; m) The concept of energy audit,
forms of energy audit; n) The approach is to use energy efficiency; o) Analyze and evaluate
opportunities to use energy efficiency in boilers used in some industries; p) Analysis and evaluation
of opportunities to save energy in the electricity production facilities.
+ 5 topic seminars
Topic 1: CP Methodology - CP Applying for a typical industry (tanning, dyeing, metallurgy,
food, paper, plastic )
Topic 2: Audit for cleaner energy
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Topic 3: Recycling and reuse of waste products in plants
Topic 4: Design for sustainable development (D4S)
Topic 5: Cleaner Production and Clean Development Mechanism: CP and CDM
+ Part 3: Building a data monitoring system cleaner production - Syllabus, sample evaluation
reports CP
- Establish monitoring systems data CP
- Outline of cleaner production assessment report.
- Presentation report on the assessment form VNCPC initiated by CP.
The methodology applied by program
Number
of
Properties
Content
Method of application

Name & chapter headings outline of teaching
6
Course Introduction
Part 1: Overview and Methodology cleaner
production approach (6 steps, 18 tasks)
Introduction: environmental
pollution and levels of
environmental management
The method presented Illustrations
+ Question
3
Part 2: Technical implementation of cleaner
production
 Internal management of the factory
 Change inputs
 Improved production technology
 Efficient use of energy
 Changes, product redesign
 Recycling and reuse in the plant
 Utilization of waste products into useful
materials
Theory
Presentation + example illustrates
Question
3
Topic 1: Cleaner Production Methodology for
Tanning Industry
Assignment: Material Balancing for CP
Performing experience
Background

3
Topic 2: Energy Audit
Assignment: Calculate the energy efficiency
Question
Homework
3
Topic 3: Recycling and Reuse
Assignment: Calculate the volume of wastes and
to propose the ability to recycle and reuse waste in
the factory
Question
Discussion solution recycling and
reuse of wastes.
4
Topic 4: Design for sustainable development
Background
Use the product division students
illustrate  discussion groups
settle the problem  Systematics
3
Topic 5: Cleaner Production and Clean
Development Mechanism: CP and CDM
Background
Discuss the solution
5
Part 3: Building monitoring data Cleaner
Production - The section should present a report of
the Cleaner Production
Presentation
The lessons given problem

Table 2 The CP problem given lessons in the course
Contents
Issues
Part 1: Methodology CP
- Businesses  cause environmental pollution are not aware of the role of
environmental protection alongside economic development. There is not a
comprehensive perspective on the relationship between environment and
economy.
- There are five approaches in environmental management: lack of access,
approach of passive and active low, active high and active. What exists in
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Vietnam is any approach, its strengths and weaknesses  environmental
approach to access in any direction? If a developing country, there should be
a passive approach (treatment end of pipe) is not?
Part 2: Technical
implementation of cleaner
production
– Tungkuang Company: "No sewage treatment, reducing costs from 90 to
100 million, used to restore the economic crisis." Do want to protect the
economic environment must be sacrificed? Fact, Waste disposal costs are
just floating icebergs of the problem and waste in the new production is the
source of "cash burn" of the business.
- Settlement of waste from? Is the consideration of the product value chain:
from the reduction of waste materials and energy to reducing toxicity,
reduction in waste products,
Topic 1: Typically cleaner
business
-

from?  cause analysis solution
Topic 2: Energy Audit
- The question: Using the boiler is not long on toilet cleaning, deposits in
boilers, consuming more energy to heat water? So to save energy in any
way?
-From the outside, it looks to save more coal and oil burning? The truth is
that? What analysts need to know the efficiency of energy use?
-We say this technology development than other technologies, the
technological level is higher than other countries, actually refers to what?
How to get only the intensity of energy consumption (GDP / TOE)
Topic 3: Recycling and
reuse
-The waste landfills increasingly appeared more related to the types of
waste packaging, industrial waste products? Europe 60% taxation on
packaging? If you produce products that can not recover packaging,
packaging for the landfills, the waste is it not? Should be recycled, reused
like?
Topic 4: Product Design for
the goal of sustainable
development (Design for
Sustainability)
-Evaluation of the environmental aspects of the shirt: from the production of
cotton, weaving, dyeing, sizing, sewing clothes, cardboard and plastic to
the environmental impact from products is not small.
1-
How to solve?
2-Story: Bat Trang is a product of traditional culture of Vietnam, but not
exported, why? What stage has not been paying attention?
3-Story: "Hot in the ": The role of other forms of marketing products like?
4-Story: "Read the directions carefully before using content." Packaging

any effect in the product?
Topic 5: CP and CDM
-Vietnam is a country of rice and water, because salt water intrusion from
sea to land.
Japan would not be proud "to have the spring cherry blossom", because
climate change is causing any warm season  Kyoto Protocol allows
countries to exchange emissions rights.
-In 2004, Vietnam's first CDM project, but why not a reality? But the
trouble?
Feedback from the faculty and students on methods of placing the subject matter for Cleaner
Production
Table 3 Surveys of students who are attending courses on cleaner production methods PBL
Reviews
The opinions of the people surveyed (%)

Good
Satisfactory
To overcome some
No
comments
Provide an overview of knowledge
68
32
0
0
Understand the objectives and requirements
clearly
59
36
0

0
Course content clearly and fully
50
50
0
0
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Subject knowledge is updated with modern
50
50
0
0
Lecture content transmitted easily understood
45
27
27
0
The method of promoting positive
36
41
23
0
Create opportunities for students to participate in
class
36
45
18
0

Answers students' questions
68
32
0
0
Effective means to teach
73
27
0
0
Source: Chamber Testing and Quality Control, HUTECH, 2010.
Table 4: Surveys of students on teaching methods subject CP
Contents
Opinion (%)
Teaching methods most used
41% held faculty
Teaching methods questioned: 59%
Time for seminars
30% of the time: 50%
20% of the time: 50%
Time of discussion, study groups
Always: 41%
Frequently: 59%
The effects of teaching methods
Very good: 50%
Meet: 50%
Type of exam application form
50% reported
50% oral
Source: Chamber Testing and Quality Control, HUTECH, 2010.

THE TEACHING EXPERIENCE
How to organize the class like?
 Clearly stated objectives should be achieved when the subject completed / lectures
 Ask students how to solve
 Make the settlement of different order
 Scheduling problem
 Set challenging situations for students to solve
 Group discussion to understand problem
 Assigned essay topic for students / student groups
For example: The four topics on product design objectives for sustainable development: after
students raised the issue  preparing several products for students to analyze advantages and
disadvantages of products: comments design concepts, production methods, packaging, product
quality, distribution, marketing? From the analysis of a product, students will understand the
process of product life cycle assessment, if limited environmental impact during product life cycle,
they must do?











Figure 1. A number of consumer products are used for student analysis.
Classify education levels
By solving problems, students will achieve skills: a) References, collected documents, b)

document links the group to draw knowledge; c) General document; d) Making plans, schedules, e)
Discussion, group work; f) Brainstorming and thinking; f) Propose a solution; g) Review the
technical feasibility / economics of the solution; h) use technology better; i) Hone presentation
skills before the crowd and protect the interests of his points have.
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Before preparing lessons, teachers identified teaching objectives and level of teaching in
which teachers want students vien.Nhung the faculty is desired in students the skills that students
achieve after complete the course.

Level
Contents
Knowledge
While learning about cleaner production, students must learn by heart the expression,
definition and data, etc They must be able to remember or get the information. Can
just learn without understanding, without thinking. This is a low level of knowledge.
When teaching about cleaner production at this level students must learn, know and
apply certain expressions without thinking.

Understanding
At this level, we expect the students to grasp the deeper problem is learning. When
discussing a specific issue CP, the student must be able to express their own language. If
a person has the ability to define a particular expression he surely must understand the
problem.
Applications
Students can apply knowledge. For example, they know the process how a machine.
For example, students learn how to use a computer or know how to use a tool how to
solve a specific problem cleaner.
Analysis

Students will separate concepts or complex information into smaller parts. They will
find out the relevant parts and simpler to understand how they work together like.
Example: They may be separated into a clock removable parts separately.
In CP there are always problems to be solved. A good method is to find the important
parts of the problem, which means the analysis of the problem.
Synthesis
Students have the ability to synthesize these elements to form the new entity. They
understand the relationship between different factors. If you can disassemble the clock,
they can rebuild.
In the CP reconstruction is very important. For example, an analysis of the production
line. Part of the chain produce too much waste should be replaced. At that time,
renovation plans have been made correctly.
Rank
This is the highest level. Students capable of ruling. Of course, to do so they need to be
familiar with the level above. In CP we must evaluate the current product line. We need
to evaluate the use of energy and resources, waste and its impact to the environment.
The complexity of levels increases from 1 to 6. Cleaner production in the department should
train students how to think at higher levels such as 4.5 and 6. Thus, in a methodologically cleaner
production and cleaner production techniques section 2 of, say teachers only and requires students
to copy. This section requires only level 1-3. But when they made the special subject students
should have skills 4-6.
Develop good teaching objectives
The building is a goal of teaching conditions, if you want to achieve a specific purpose. If
you do not know where you go, you will never achieve a goal. The best teachers often have in
common, but not in technique, method or style of teaching. Main what they've done, not how they
finish makes the difference. CP in teaching, the instructor should closely follow the three
objectives of teaching:
The general
idea
Why use this lesson? What is it useful? Here we are building a common framework for

their teaching. This work will help us see clearly what content should be put on lectures
and not content. May include an analysis, one that reflects the needs and the methods
used.
Using the
teaching goals

This section indicates what students know more after the lecture comes to results. It
could be a new awareness, new strategies or new skills to use etc

The goal was
to use
teaching
Describe activity. After listening to lectures, students will react in different ways
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A goal of good teaching is targeted to meet these criteria: i) The student orientation; ii) A
description of the study results will be achieved; iii) To establish clear objectives and easy to
understand; iv) use the easy target of teaching observations.
Know how to ask questions
If you want students to be proficient using new skills, teachers should be obliged to find and
think of situations in which students can test their new skills. If the instructor to point, students can
base on which to know their progress. You can do this by asking questions. When you ask
questions, send messages together. "I will support you to become a true expert." The activities of
teachers, including: i) Bringing out the exercises; ii) The exercise includes questions to answer. The
article was very important for students; iii) Requires students to write down the questions / issues
arise in the lesson and discuss the validity of the test questions. Trainers must ask questions to elicit
the views of students. The requirements of the question:

Do exercises
Teacher introduces the lesson topic to a certain point so students can understand and begin to
focus on homework. It is not only the extent of application as a method of learning by heart, without
thinking. Exercises require students to have to think out how to solve problems. So teachers should
be able to:
- Find a suitable situation to be able to use methods
- Establish an information base from which students can work independently
- Find the time students begin working independently.
Note the following:
- The lecture must be in writing
- Teachers do not help students
- Allowed general suggestions about the conduct of how
- Teachers, students will decide to work in teams or work independently
- Referring to the criteria for determining success
Manners
We can ask questions beginning lessons, the learning process or the end of the lesson. The
questions related to information inside and outside the classroom. Students need to have time to
answer my question. Usually students need at least 3 seconds duration. If not for the time, they will
not think anything. Think of a combination of questions in different ways: i) Require the skills to

create images, graphics, ii) establish definitions; iii) Copy; iv) recognize the problem from a
different perspective together; v) Comparing; vi) Classification; vii) Developing new ideas; viii)
Conclusions; ix) Evaluation.
Record personal factors in teaching methods
From level 1, level 2, level 3 and the Foundation, we have spent 15,000 lessons in the
classroom. We have been in contact through various teaching methods of teachers. But have you
ever questioned why they were teaching that way of teaching them yet? Did you ever think about
Create conditions
for students to
express their
opinions
Assessing the
quality of student
Questions must be
clear
Clarify the accuracy
of the questions
Turn the question
into a habit
Requirements
of the
question
Teachers'
expectations must be
clear
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their subject teachers do not? What makes a teacher?
The individual characteristics

- Sex: female teachers generally tolerant and motivate students, male teachers often follow the
department.
- Age: In the early years of teaching teachers is often better and then how the quality
decreases slightly. Young teacher adaptable to changes and improvements. More easily because
they impose do not feel sure.
- Personality traits in the overall behavior and personality: People have their own needs,
including achievements and relationships (friendships formed) and managed.
Experience in teaching
- The way we were taught before will affect the way we teach our students. Mimicking skills
are people skills most easily absorb. We can distinguish between direct instruction (in which
teachers set goals, use materials and construction sequence and describe what students did) and
indirect methods of teaching, in that teachers set more general goals, using a variety of learning
materials and allow students the freedom to achieve their goals. In the curriculum, the courses of
specialized technical environment is often preferred to teach by the direct method, also the subject
of environmental management are preferred to teach in more indirect method. Indirect form of help
students can freely apply their minds to question, and go to the issue.
Background
- Character's very important to students. Explore your students. An experienced teacher will
look at a class of individuals. A class can be oriented to achieve more than just separation.
Question:
- Teaching Equipment: You are allowed to use the equipment if good teaching. The more
modern teaching equipment we will bring more knowledge to students, helping students more
receptive.
- Time: If you have time, we can apply the strategy of indirect learning. Currently the
universities through training in the form of credits, amount of class time duration equivalent to at
home, teachers should take initiative for students in the form of indirect.

CONCLUSION - RECOMMENDATIONS
Education is an important part in real life. Education Foundation which is a common goal of
social work training in the professional human resources for the country. Teaching method is the

question as to shorten the gap between reality and theory, helping students closer touch with real,
complete knowledge, skills and attitude. And the fact that, in applying the method of teaching
subjects in CP Engineering Technology University City was a major positive signal. The following
students were crestfallen time gradually acquainted, and know how to adapt organizational learning,
explore materials, self-study and discussions effectively.
Currently, most universities have turned to forms of credit, the courses on the environment
and reduce the number of lower class to class time. Therefore, the method of teaching performance,
monologue, read the copy was no longer promote its effects. Measures to promote positive thinking,
put learners in a central location such as teaching methods are being questioned as a prospective
measures need to expand on the model training credits.

REFERENCES
Chamber Testing and Quality Control, Lecturer ‗s Analysis, Ho Chi Minh City University of
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