Dialogue-based Experiment Design Process

Since contents in script language have many dependence relations, and many contents reference preprocessed default knowledge, we use a dialogue-based knowledge acquisition to help teacher fill out the script. The dialogue-based approach has two objectives, one is to reduce cost in experiment construction, and the other is to keep the identical of notations that have dependency in this script.

A dialogue algorithm is proposed in Figure 11. In the first phase, teachers need to specify experiment elements which include scenes, devices, structures and variables.

Teachers just name the elements without configuration of details. The phase is similar to design a hands-on experiment. Teachers don’t need to describe the details, because most of details belong to the default knowledge which means default values of hands-on experiments. The details setting would be finished through the following dialogue phase. In the second phase, teachers will be asked to set the value of variables that have relation to scenes. The third phase is for the configurations of devices. Since most of devices belong to default knowledge, the attributes and actions are predefined, teachers will be asked to set values of the attributes without defining attributes of them. There are still experimental objects need to define attributes and actions. We use variables defined in the first phase to help teacher add the attributes of experimental object. In the fourth phase, teachers define the structure. We will guide

teacher to chose devices for composition. Then for attributes and actions of every composed device, the teacher is asked to determine whether the attributes and actions of the composed devices are inherited by this structure. The teacher could still extend new attributes or actions in the structure. The fifth phase is operation setting phase.

We hint teacher with each variable defined in the first phase. The teacher will be asked the operation flow to change the variable. In the last stage, the teacher could define rules to describe how the time could affect the experimental results.

Figure 11. Dialogue Algorithm

Example 12: Using dialogue-based script language to edit the experiment “The related factors in transpiration speed of plants”

First phase: Specify Experiment Element

Teachers name the four parts as they design a hands-on experiment.

Scene: laboratory, playground

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Device: graduated cylinder, knife, water vat, ruler, red ink, celery Structure: celery in the graduated cylinder

Variable: temperature, leaves number of celery, stem length of celery

Table 20. The script content in second phase of dialogue-based experiment construction

Second phase: Scene Setting

Consider the variables that have relation to scene. Since temperature has relation to scenes, teachers are asked to decide the temperature of each scene as follows.

Scene Setting

Place Context Attribute Value

laboratory temperature 25

Playground temperature 30

Table 21. Part 1 of the script content in the third phase of dialogue-based experiment construction

Third phase: Device Setting

In this experiment, devices like graduated cylinder, knife, water vat, ruler and red ink are belong to default knowledge. Thus we provide predefined attributes of

teachers to fill out the value. For the device graduated cylinder, teacher only has to set the values which are underlined in the following table.

Device Setting Device

Name

Number Attribute / Action Name

picture String measure.gif

contained liquid Record (none,0,0,0)

capacity Number 100

material String glass

Then we consider the celery. Celery belongs to experiment-specific knowledge.

Thus teachers have to define its attributes and actions. We use variable to guide teacher in adding the attributes and actions. For variable “leaves number of celery”, we ask teacher the way of how to change leaves number. First the celery need to have an attribute called leaves number, and the celery need some different pictures to show different leaves number. After the action “pluck leaves” is triggered, the picture of celery is replaced by the corresponding picture according to the number of leaves.

Table 22. Part 2 of the script content in second phase of dialogue-based experiment construction

Device Setting Device

Name

Number Attribute / Action Name

picture string celery1.gif, celery2.gif, celery3.gif

Pluck leaves Procedure 1.Change picture

2.change “leaves number”

attribute

Cut stem Procedure 1.change picture 2.change “stem cut”

attribute

Inhale red ink Procedure 1.change picture Immerse in

water

Procedure 1.change “in the water”

attribute

In the first phase teachers already name a structure called “celery in the Forth phase: Structure Setting

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graduated cylinder.” In this phase first step is to list all the composing devices. Then we will guide teacher via asking them if those composing devices have attributes or actions need to keep in the structure. Those inheritance attributes and actions are automatically filled in third column and fourth column.

Table 23. The script content in forth phase of dialogue-based experiment construction Structure Setting Pour out Graduate

cylinder

n/a n/a

Table 24. The script content in fifth phase of dialogue-based experiment construction Fifth phase: Operation Setting

We ask teacher the operations to achieve the change for each variable. For variable “stem length of celery”, it can be achieved by two operations. The two actions are immersing celery into water and cut the celery stem. Thus it forms two operation settings.

Operation Setting

Actor Manipulate Target Conditions Reaction celery Drag in water vat none Trigger celery

“immerse in water”

action

knife Drag with line celery Celery’s attribute Trigger celery “cut

“stem cut” has value “none”

stem” action

Table 25. The script content in sixth phase of Dialogue-based experiment construction Sixth phase: Time Setting

In this experiment teachers define the red ink decreasing amount in different conditions.

Time Setting Passed time

Target Condition Reaction

10 celery in the

graduated cylinder

Leaves numbers of celery = 10

trigger action “Inhale red ink” and

“Pour out” with degree equals 12

10 celery in the

graduated cylinder

Leaves numbers of celery = 5

trigger action “Inhale red ink” and

“Pour out” with degree equals 6

10 celery in the

graduated cylinder

Leaves numbers of celery = 0

trigger action “Inhale red ink” and

“Pour out” with degree equals 2

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Chapter 5. Implementation and Experiment