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The Conflict Graph for Maintaining Case–Based Reasoning Systems

The Conflict Graph for Maintaining Case–Based Reasoning Systems
The Conflict Graph for Maintaining Case–Based Reasoning Systems

The Con?ict Graph for Maintaining

Case–Based Reasoning Systems

Ioannis Iglezakis

DaimlerChrysler AG,Research&Technology,FT3/AD,

P.O.Box2360,89013Ulm,Germany

ioannis.iglezakis@https://www.doczj.com/doc/0d16909111.html,

Abstract.The maintenance of case–based reasoning systems is remarkably im-

portant for the continuous working ability of case–based reasoning applications.

To ensure the utility of these applications case properties like correctness,consis-

tency,incoherence,minimality,and uniqueness are applied to measure the qual-

ity of the underlying case base.Based on the case properties,the con?ict graph

presents a novel visualization of con?icts between cases and provides a technique

on how to eliminate these con?icts and therefore maintain the quality of a case

base.An evaluation on ten real world case bases shows the applicability of the

introduced technique.

1Introduction

During the last years,the research in the realm of case–based reasoning(CBR)systems in general and maintaining of case–based reasoning systems in particular has become a main topic for many researchers.In the?eld of maintaining case–based reasoning systems various measures like coverage and reachability[14,17]and thereby case com-petence[15]are modeling the competence of a case base.The use of case properties which show the relations within cases and between cases[11]is an other way to measure the quality of a case https://www.doczj.com/doc/0d16909111.html,pared to the standard case–based reasoning cycle[1],the case properties are embedded in an extended case–based reasoning cycle[12]with the two additional steps:review and restore.The review step detects con?icts within and between cases with the help of the case properties.These con?icts are then monitored and the decision is made when to maintain and therefore trigger the restore step.The re-store step suggests the necessary changes for the contents of the case base to reestablish the quality.

This paper focuses on the monitor task of the review step and how it can be used to restore the quality of the case base.It introduces a new visualization for the con?icts between cases—the con?ict graph—and shows how this con?ict graph can be used to?nd a subset of cases which must be changed in order to restore the quality of a case base.Therefore the needed case properties are revisited in section2.The concept of

a con?ict graph is de?ned in section3,followed by results of an evaluation in section

4.Section5discusses the related work.Finally,section6concludes the paper with a summary and issues of further work.

2The Case Properties Revisited

As explained above,the review step in the extended case–based reasoning cycle has among other things like monitoring the quality of the case base the duty of measuring the case base through case properties.These measures are disjunct and used for quality indication within cases or between cases.The formal de?nition of the case properties which are used here can be found in[11].In this section only an informal description of the case properties correctness,consistency,uniqueness,minimality,and incoherence is given to motivate them for further use in the next sections.

2.1Correctness

There are two kinds of case properties:isolated and comparative.Correctness is the only isolated property,because the correctness of a case can be recognized without considering any other case.A case is believed to be correct if and only if the problem description of the case corresponds to the given solution.This implies that the solution solves the problem that is described by the problem description.Note that for the fol-lowing descriptions of case properties and experiment the correctness of the cases is assumed.

2.2Consistency

The?rst of the comparative case properties is consistency.A given case is called con-sistent if and only if there is no other case whose problem description is a subset or the same of the given case’s problem description and their solutions are different.Hence, consistency covers situations where the subset relation between problem description with different solutions reports that there possibly is an absence of some attributes or values to make the two cases distinctive.

Table1illustrates a counter–example from the help–desk domain when two cases are not consistent.This example shows two cases with the same operating system,the

Table1.Example for(in-)consistency

Operating System Printer Printing Paper Ink Solution

WinNT HP840c No Yes Yes Update Driver

WinNT HP840c No——Second Level

same printer and no printing.In addition,the?rst case has more information about the paper and ink situation than the second.Note that the value“—”for the paper and ink attribute in the second case means the these values are unknown.Thus,with regard to the above description the second case is not consistent,because the problem description of the second case is a real subset of the?rst case and the solutions are different.

In general,consistency contains the occurrence of alternatives.It is assumed that for each capable problem description there exists a“best”solution.As a matter of course, the case base should only consist of cases that have“best”solutions.Thus,no alternative solutions are allowed neither as an alternative in the same case nor as a further case with the same or a more general problem description and a different solution.

Note that it is possible for some domains to have equivalent solutions for the same or more general problem description.The travel domain is a good example for this kind of domain and it is up to the case base administrator to decide whether these alternatives are admitted or not.

2.3Uniqueness

Another comparative case property is uniqueness.A given case is called unique if and only if the problem description and corresponding solution of each other case in the case base is different.A counter–example from the help–desk domain is displayed in table2.It describes the fact when the given case property uniqueness is violated.

Table2.Example for(not)unique

Operating System Printer Printing Paper Ink Solution

WinNT HP840c No Yes Yes Update Driver

WinNT HP840c No Yes Yes Update Driver For both cases in this example,the problem descriptions and solutions are exactly the same.With the above description of uniqueness follows that both cases are evidently not unique.

2.4Minimality

The third comparative case property is minimality which means the opposite of sub-sumption.A given case is called minimal if and only if there is no other case for which the problem description is a real subset of the given case and the solutions are identical. This concept is clari?ed by the counter–example in table3which contains an example when two cases are not minimal.

In this table both cases are identical besides the value for the operating system.The ?rst case contains a value for the operating system while the second case does not.This disobeys the de?nition of minimality because the problem description of the second case is a real subset of the?rst case’s problem description and the solution for both cases are equal.

Table3.Example for(not)minimal

Operating System Printer Printing Paper Ink Solution

WinNT HP840c No Yes Yes Update Driver

—HP840c No Yes Yes Update Driver

2.5Incoherence

Finally,the last comparative case property is incoherence.A given case is incoherent if and only if each other case with the same solution as the given case has the same prob-lem description with the exception of a speci?c(small)number(?)of attributes whose values are different.To illustrate this case property in table4once more a counter–example is used.

Table4.Example for(not)incoherent(for?=1)

Operating System Printer Printing Paper Ink Solution

WinNT HP840c No Yes Yes Update Driver

Win95HP840c No Yes Yes Update Driver Both cases in table4have the same solution and differ only in the value for the oper-ating system and in contrast to the minimality example in both cases these values exist. With the assumption that?=1and the above description it follows that these two cases have a con?ict with the de?nition of incoherent and are therefore not incoherent.

This section gave an informal description of the case properties in combination with examples from the help–desk domain.With these descriptions it is possible to build case base properties in which the case properties are assigned to a whole case base.For example,if each case in a case base is minimal,then the entire case base is by de?nition also minimal.To receive a better granularity of assessment,the case properties can be measured in degrees within the case base.The measurement for each case property is computed by counting the number of cases which ful?ll this property divided by the total number of cases in the case base.This mapping of sets to numbers offers a more sophisticated way to measure the quality of the case base.Finally,quality measures are de?ned as a function over the degrees of case properties.For example,a weighted sum could respresent one usable function.More information on the subject of quality measures for case base maintenance can be found in[11].In the following section,the notion of the con?ict graph is introduced.This notion can help to visualize the con?icts between cases and decide which cases should be changed in order to restore the quality of a case base.

3The Con?ict Graph

After measuring the quality of the case base with the help of the case properties,the next step is to monitor these results.This section will introduce a novel method to display con?icts between cases which are indicated by case properties and how this representation can be used in order to maintain a case base.

When applying the described case properties from the previous section to the case base it is usually that not all properties are satis?ed and thus the degree of case prop-erties is below100%.This means that for some cases a case property is not ful?lled. The purpose of the single con?ict indicators in de?nition1is to test two cases for a particular case property and to indicate a possible con?ict.

De?nition1(Single Con?ict Indicator).Assume a case base C with two cases c i,c j∈C and i=j.

(i)cInd1:C×C→{?consistent,?},

cInd1(c i,c j):= ?consistent,if c i is not consistent with c j

?else

(ii)cInd2:C×C→{?incoherent,?},

cInd2(c i,c j):= ?incoherent,if c i is not incoherent with c j

?else

(iii)cInd3:C×C→{?minimal,?},

cInd3(c i,c j):= ?minimal,if c i is not minimal with c j

?else

(iv)cInd4:C×C→{?unique,?},

cInd4(c i,c j):= ?unique,if c i is not unique with c j

?else

To explain the above as well as the following de?nitions an exemplary case base is designed.Table5shows this case base with seven cases.Each case c i contains the solution s i and the problem description p i which encloses the attribute–value pairs v ij.

Table5.Example case base with seven cases

c i p i s i

c1v11s1

c2v12v22s1

c3v11v22s1

c4v12v22v33s2

c5v11v23v35s1

c6v11v23v34s1

c7v11s1

Example1(Single Con?ict Indicator).Assume the cases c1and c6from the case base given in table5and the single con?ict indicators cInd1and cInd3.The results are: cInd1(c1,c6)=?and cInd3(c1,c6)=?minimal.

After de?ning the single con?ict indicators the next step is to de?ne the con?ict indicator set which is then used to build the con?ict indicator.

De?nition2(Con?ict Indicator Set).Assume the indices of all single con?ict indi-cators I={1,...,n},where n is the maximum number of single con?ict indicators, and I?the set of all subsets of I.The con?ict indicator set M is de?ned as M∈I?with M=?and m l∈M where l denotes the l–th element of M.

The purpose of the con?ict indicator set is to choose which single con?ict indicators are used to con?gure a con?ict indicator.Note that for the single con?ict indicators given in de?nition1the maximum number n of single con?ict indicators is n=4 which limits the possible number of different con?ict indicator sets to2n?1=15. De?nition3(Con?ict Indicator).Assume a case base C with two cases c i,c j∈C and i=j,and M is a con?ict indicator set.

cInd:I?×C×C→{?consistent,?incoherent,?minimal,?unique,?}, cInd(M,c i,c j):= |M|l=1cInd m l(c i,c j)

Note that for the given single con?ict indicators cInd k in de?nition1the value of |cInd(M,c i,c j)|is0or1for all con?ict indicator sets M and pairs of cases c i,c j.

The con?ict indicator is a composition of the single con?ict indicators.The con?ict indicator set M determines the con?guration of which single con?ict indicators are used.The results are the kind of con?icts between two cases or the empty set if all case properties are satis?ed.Example2illustrates this behavior.

Example2(Con?ict Indicator).Assume the cases c1and c6from the case base given in table5and the con?ict indicator set M={1,2}and M ={3,4}.Then results are cInd(M,c1,c6)=?,and cInd(M ,c1,c6)=?minimal.

The con?ict graph creates a graphical representation of con?icts between two cases within a case base which are indicated through the con?ict indicator.This means that the con?ict graph contains all the cases which have con?icts detected by the case properties and connects these cases with a labeled edge.The label depends on the kind of property violation.De?nition4formalizes this in a more detailed form.

De?nition4(Con?ict Graph).Assume a case base C={c1,...,c i},a con?ict indicator set M,a set of nodes N∈C?where C?is the set of all subsets of C,and a set of edges E?N×N with e jk∈E and e jk de?nes an edge from node of case c j to node of case c k with label cInd(M,c j,c k)if and only if cInd(M,c j,c k)=?. The con?ict graph G=(N,E,M)is a directed Graph with labeled edges and?c j∈N,?c k∈N:cInd(M,c j,c k)=?and?c j∈C\N,?c k∈C:cInd(M,c j,c k)=?.

Note that for some case bases it is possible to have more than one con?ict graph which are not connected.For example,if a case base has four cases {c 1,...,c 4}and c 1has only an inconsistency con?ict with case c 2,case c 3has only a minimality con?ict with case c 4and no other con?icts are detected,then the result would be two con?ict graphs with the cases c 1and c 2in the one and the cases c 3and c 4in the other graph.

Figure 1shows the con?ict graph for the example case base given in table 5.The graph displays thirteen con?icts within the case base.One consistency con?ict (c 2,c 4),four incoherence con?icts (c 2,c 3),(c 3,c 2),(c 5,c 6),(c 6,c 5),six minimality con?icts (c 1,c 3),(c 1,c 5),(c 1,c 6),(c 7,c 3),(c 7,c 5),(c 7,c 6),and two uniqueness con?icts which are (c 1,c 7)and (c 7,c 1).Note that with the increasing number of cases the con?ict graph

Fig.1.The con?ict graph for table 5

can confuse a human observer like the case base administrator.However it is possible to cluster groups of con?ict cases and present these groups ?rst with the ability to navigate into these groups.

The advantage of the con?ict graph in comparison to other representations like ad-jacent lists is the ability to display the cases which do not satisfy the de?ned case prop-erties in a compact manner.Thus,the case base administrator can decide which cases have to be modi?ed to restore the quality of the case base.However this decision is very complex because the goal is to modify at least as possible cases dependable on the arising costs.The following de?nitions do support the case base administrator within this task by identifying the cases which should be modi?ed.Hence,the following de?-nitions can help to automate the parts of the restore step within the extended case base reasoning cycle.

De?nition5(Independent Graph).A Graph G=(N,E,M)with con?ict indicator set M is independent if and only if there is no pair of nodes n i,n j∈N for which G de?nes an Edge e ij∈E.

Graph G=(N,E,M)is independent:??E=?

An independent graph is the result after the decision is made which cases have to be modi?ed.It is a graph in which the nodes have no edges and therefore no con?icts which each other.For example,if the cases{c1,c3,c4,c5,c6}are removed from the con?ict graph in?gure1then the resulting graph would be independent.However it is not appropriate to remove too many cases because of the unnecessary loss of knowledge and the costs which appear with each modi?cation of the case base.Note that instead of removing a case other modify operators are possible.For simplicity,in this paper only the remove operator is considered.A list of more sophisticated modify operators can be found in[12].

De?nition6(Optimal Subset).Assume the con?ict graph G=(N,E,M),the set N?of all subsets of N,the con?ict indicator set M,the cost function cost:N?→[0;1],N ∈N?,and the graph G =(N ,E ,M)is independent.

N is the optimal subset within N?:?? N ∈N?:cost(N )>cost(N ) and the graph G =(N ,E ,M)is independent.

De?nition6states that the optimal subset of a con?ict graph creates an independent graph and is mainly dependable of a cost function.The cost function is an arbitrary function which describes the optimization goal.Example3introduces a cost function for which the search for an optimal subset becomes equivalent to the search for a max-imum independent set.

Example3(Maximum Independent Set).Assume a con?ict graph G=(N,E,M), a node subset N ∈N?,and a cost function cost:N?→[0;1],cost(N ):= |N |/|N|.Then the search for an optimal subset is equivalent to the search for a maxi-mum independent set.For the con?ict graph in?gure1the maximum independent set is(c3,c4,c5),or(c3,c4,c6).Note that the search for a maximum independent set is N P?complete[13].

The case base administrator can control the search for an optimal subset on three different ways.If there exists more than one solution for the optimal subset like in example3then the?rst way is to decide which of the possible solution is adequate for the actual situation.The second way is to mark the cases which should be put in the optimal subset.This can totally change the behavior of the algorithm which searches for the optimal subset.For example,if case c1is marked for the con?ict graph in?gure1, then the optimal subset with the same cost function as in example3is(c1,c2)or(c1,c4) and hence different from the optimal subset without any interaction.Finally,the third way is to mark the cases which should not be included in the optimal subset.Again, this would change the manner of how to search for the optimal subset.For example,if case c5is marked for the con?ict graph in?gure1,then the optimal subset with cost function like in example3is(c3,c4,c5).

4Evaluation

The last section introduced the con?ict graph and how it can be used to indicate a subset

of cases which should be changed to restore the quality of the case base.This section

will present an evaluation of these con?ict graph related techniques for the maintenance

of case–based reasoning systems.

4.1Experimental Procedure

To perform the experiments,the data set of cases is divided into a training set and a

test set.The training set becomes the case base and is then used for the case–based

reasoning algorithm.Then each case from the test set is tested against the case base

within a case–based reasoning algorithm.This implements the benchmark for the other

experiments and a certain accuracy and case base size is acquired.To achieve the re-

maining experiments the training case base is optimized.Thus,the con?ict indicator is

con?gured with the following con?ict indicator sets{{1},{2},{3},{4},{1,2,3,4}}.

This means that each single case property was applied on its own as a con?ict indicator

and then all properties together.For the optimization the same cost function is chosen as

in example3:cost:N?→[0;1],cost(N ):=|N |/|N|where N denotes the Nodes in the con?ict graph and N ∈N?.This means that the search for the optimal subset is N P?complete.Algorithm1is a heuristics to calculate a not necessarily optimal so-lution of the optimal subset for a given graph.The algorithm returns a nodes–collection

which is then viewed as the optimal subset and the graph which can build from the

nodes–collection is guaranteed to be independent.

Algorithm1(Heuristic to calculate the optimal subset for a given graph).

nodes–collection:=nodes of graph

while(nodes–collection does not build an independent graph)

n:=node with the maximum number of incoming and outgoing edges

remove node n from nodes–collection

end while

return nodes–collection

Furthermore,the optimization’s modify operator is remove and the optimization is done

automatically without human interaction.After optimizing the case base the test cases

are applied to the case base,a level of accuracy is reached,and the case base size is

registered.

4.2Experimental Results

The aim of the prede?ned benchmarks and experiments is to show that the representa-

tion of the con?ict graph and the following search for the optimal subset is applicable

for maintaining case–based reasoning systems.

To accomplish this,data of the UCI Machine Learning Repository[6]is taken.

Namely,the following case bases are used:Annealing(797cases),Audiology(200

cases),Australian(690cases),Credit Screening(690cases),Housing(506cases),Let-ter Recognition(16000cases),Pima(768cases),Soybean(307cases),Voting Records (435cases),and Zoo(101cases).To achieve the results that are presented below,a ?ve–fold cross validation with a basic optimistic nearest neighbor algorithm is used.If numerical attributes did occur they have been pre–processed by a standard equal–width discretization.

Table6.Results

benchmark consistency incoherence minimality uniqueness all properties case base size acc.size acc.size acc.size acc.size acc.size acc. Annealing637.60.97622.80.97416.00.97532.60.97574.80.97335.60.97 Audiology160.00.70160.00.70144.20.70156.00.70145.20.69128.60.70 Australian552.00.81550.60.81509.40.80552.00.81548.60.81506.00.80 Credit S.552.00.80550.60.80508.80.79551.40.80549.00.79505.60.78 Housing404.80.31404.20.31391.20.30404.80.31401.40.30387.20.30 Letter R.16000.00.8816000.00.8814787.80.8816000.00.8815081.40.8814044.60.88 Pima614.40.65614.40.65575.60.65614.40.65612.00.65573.00.65 Soybean245.60.92244.80.92217.00.92245.00.92243.20.92213.20.92 V oting R.348.00.93344.40.92257.60.93271.60.93280.60.93191.80.93 Zoo80.80.9580.80.9553.80.9580.80.9550.40.9533.40.95 Table6shows that optimization through the case properties keeps the case base con-sistent,incoherent,minimal,and unique and reduces the case base size while preserving the prediction accuracy.

For the single case properties as con?ict indicators,the case base size is reduced up to34.8%from the original case base for incoherence in the annealing case base and the reduction for all properties as con?ict indicator is up to58.7%while the prediction accuracy remains the same as in the benchmark.The combination of all case properties gives each time a better case reduction result than the single case properties.The results vary from0.5%between incoherence and all properties in the pima case base and33.7% between uniqueness and all properties in the zoo case base.

In addition,the letter recognition case base with16000cases shows that the de-scribed technique is applicable for large case bases,too.

Furthermore,in comparison with the results in[8]which uses a different kind of optimization the results for the prediction accuracy were better and thus more robust against the used case base domain.Moreover,this evaluation used combinations of the case properties while the earlier did not.Another advantage of the optimization used in this evaluation is that it is possible to have an interaction with the case base administrator.

This shows that with the help of the con?ict graph and the search of an optimal sub-set within this graph it is possible to maintain a case base reasoning system.Furthermore with the interactive help of a case base administrator the results should improve.

5Related Work

The formal de?nitions of the case properties used for the con?ict graph can be found in Reinartz et al.[11].Several additional measures like case base properties,degrees of case properties,and quality measures are de?ned there,too.Evaluations showing that case properties are valueable for maintaining case–based reasoning systems have been done by Iglezakis et al.[7,8].The extension of the standard case–based reasoning cycle and the de?nitions of the modify operators were?rst proposed by Reinartz et al.[12].

The use of graphs to maintain conversational case libraries(CCL)has been pre-sented by Aha[3]and Aha and Breslow[4,5].The CCL is applied to a transformation process which produces hierarchies.Then the hierarchies are pruned with the help of some design guidelines provided by case–based reasoning vendors.The resulting hier-archies are transformed back into cases of the CCL.

Over the years there where different kinds of measures for the maintenance of case–based reasoning systems published.Racine and Yang[9,10]proposed the measures for inconsistency and redundancy for the maintenance of large and unstructured case bases.Furthermore,with the access and use of background knowledge it is possible to differentiate between intra–case and inter–case measures.Smyth and Keane[14] described two different measures—coverage and reachability.The coverage of a case is the set of all problems in the problem area which can be solved by this case through adaptation.The reachability of a case is the set of all cases which are used to solve this case through adaptation.These two measures lead to different strategies how to preserve the competence of the used case base,namely case deletion by Smyth and Keane,and case addition introduced by Zhu and Yang[17].In addition,Smyth and McKenna[15]presented the measures for case density and group density for modeling competent case–based reasoning systems which are case addition strategies,too.More strategies on how to decide which cases should be stored are proposed by the DROP1–DROP5and DEL Algorithms by Wilson and Martinez[16],and Aha’s CBL1–CBL4 algorithms[2].

6Conclusions

With the help of case properties it is possible to create consistent,incoherent,minimal, and unique case bases.These properties have been shown to be valuable in the?eld of maintaining case–based reasoning systems.The application of these properties is the ?rst step in a framework for maintaining case–based reasoning systems,to monitor the properties and then if necessary to restore the quality of the case base are the next steps.

This paper introduced a novel method to visualize con?icts between cases which are detected by the case properties and how to use this presentation to maintain a case base. This is accomplished by formal de?nitions of the con?ict graph and the optimal subset. The subsequent evaluations showed that the proposed concepts and methods are useful

for maintaining case–based reasoning systems,by reducing the size of the evaluated case bases and preserve the prediction accuracy while satisfy the case properties.

Further tasks appear on both sides of the review–restore chain of the extended case–based reasoning cycle.At the beginning of the chain,the case properties can be ex-tended by the use of the similarity measures.This would allow the application of the case properties more?exibility in use.On the other side of the chain the use of other modify operators than remove(cf.Reinartz et al.[12])provides a strong technique for not only reducing the case base size but also for changing the cases which have con?icts and therefore increasing the quality of the case base.This would yield to an approach which does improve the cases rather than remove them.

Acknowledgments

The author is grateful to Thomas Reinartz(DaimlerChrysler,Research&Technology, FT3/AD)and Thomas Roth–Berghofer(tec:inno—empolis knowledge management GmbH)for the fruitful discussions and continual support.

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Windows系统自带画图工具教程87586

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认识画图软件教案

《认识画图软件》教学设计 任教教师:苗丽娟 所在学校:复兴小学

《认识画图软件》教学设计 教学目标: 1、能熟练启动并退出画图软件; 2、认识画图软件的窗口并了解各种绘画工具的使用; 3、能绘制简单的图形。 重点难点: 了解各种绘画工具的使用。 教学时间:一课时 课前准备: 课件 教学过程: 一、导入 1、今天的天气真好,阳光明媚,老师和大家一起来欣赏一些作品(出示课件) 师:这些画漂不漂亮,它们不仅漂亮而且还很神奇。因为不是用笔和纸画出来的,而是用电脑上的画图软件画出来的。同学们想不想成为一名电脑绘画小高手。那就和老师一起来学习这一课:认识画图软件(课件出示) 二、新授 1、启动画图软件: 课件出示启动画图软件的方法,请同学们根据课件演示操作。 2、认识画图软件窗口: 课件出示画图软件窗口。 3、认识工具箱 (1)师问:工具箱中有多少个按钮? 师:告诉大家一个方法,当我们把鼠标指针放到某个工具上时就会在它的旁边出现它的名字,而且下面任务栏中会出现对这个工具使用方法的介绍。 现在就请大家发挥你的小组合作能力,自主的探究一下这些工具: (2)课件出示:合作探究:工具箱中的各种工具有些什么作用?怎样使用?

(3)师说明活动要求:两人为一个小组进行合作,解决上述问题。 (4)学生操作。师和学生单独交流,了解学生学习情况,收集学生问题。(5)师问:谁愿意说说你对哪个工具最了解?它的名称是什么?怎样使用?(学生边说边演示,鼓励台下学生向台上演示的学生提出不懂的问题并寻求解决方法) 4、认识调色板: 课件出示选色框图:上面框中的颜色称为前景色,下面框中的颜色称为背景色 我们已经简单的认识了一些工具,现在我们画一个简单的图形并给它涂上颜色。 生画完后,师:在刚才的上色过程中为什么只有前景色会变化?背景色怎样改变?大家尝试一下。 师总结:单击左键拾取前景色,单击右键拾取背景色。 课件出示儿歌: 调色板儿真方便,多种颜色我来选。 单击左键前景色,单击右键背景色。 前景背景不一样,两键单击记心间。 三、退出画图软件 师:当图软件用完之后,怎样退出呢?聪明的你们能不能从课本上找到答案?有几种方法? 第一种: 单击“文件(F)”菜单中的“退出(X)”命令,可以退出“画图”程序。 第二种:按一下右上角的× 师:如果还没有保存画好或修改过的图形,则在退出“画图”程序时,屏幕上会出现“画图”对话框,这时,如果单击“是(Y)”按钮,则保存图形后再退出;如果单击“否(N)”按钮,则不保存图形就退出;如果单击“取消”按钮,则不退出“画图”程序。 四、赛一赛

pymol作图的一个实例演示教学

p y m o l作图的一个实 例

Pymol作图的实例 这是一个只是用鼠标操作的初步教程 Pdb文件3ODU.pdb 打开文件 pymol右侧 All指所有的对象,2ODU指刚才打开的文件,(sele)是选择的对象 按钮A:代表对这个对象的各种action, S:显示这个对象的某种样式, H:隐藏某种样式, L:显示某种label, C:显示的颜色 下面是操作过程: 点击all中的H,选择everything,隐藏所有 点击3ODU中的S,选择cartoon,以cartoon形式显示蛋白质 点击3ODU中的C,选择by ss,以二级结构分配颜色,选择 点击右下角的S,窗口上面出现蛋白质氨基酸序列,找到1164位ITD,是配体点击选择ITD ,此时sele中就包含ITD这个残基,点击(sele)行的A,选择rename selection,窗口中出现

,更改sele为IDT,点击(IDT)行的S选择sticks,点击C,选择by element,选择,,调整窗口使此分子清楚显示。 寻找IDT与蛋白质相互作用的氢键: IDT行点击A 选择find,选择polar contacts,再根据需要选择,这里选择to other atoms in object ,分子显示窗口中出现几个黄色的虚线 ,IDT行下面出现了新的一行 ,这就是氢键的对象,点击这一行的C,选择red red,把氢键显示为红色。 接着再显示跟IDT形成氢键的残基 点击3ODU行的S,选择lines,显示出所有残基的侧链,使用鼠标转动蛋白质寻找与IDT以红色虚线相连的残基,分别点击选择这些残基。注意此时selecting要是residures。选择的时候要细心。取消选择可以再次点击已选择的残基。使用上述的方法把选择的残基(sele)改名为s1。点击S1行的S选择sticks,C选择by elements,点击L选择residures显示出残基名称.在这个例子中发现其中有一个N含有3个氢键有两个可以找到与其连接的氨基酸残基,另一个找不到,这是因为这个氢键可能是与水分子形成的,水分子在pdb文件中只用一个O表示,sticks显示方式没有显示出来水分子,点击all行S选择nonbonded,此时就看到一个水与N形成氢键

使用画图工具

如何使用画图工具 想在电脑上画画吗?很简单,Windows 已经给你设计了一个简洁好用的画图工具,它在开始菜单的程序项里的附件中,名字就叫做 “画图”。 启动它后,屏幕右边的这一大块白色就是你的画布了。左边是 工具箱,下面是颜色板。 现在的画布已经超过了屏幕的可显示范围,如果你觉得它太大了,那么可以用鼠标拖曳角落的小方块,就可以改变大小了。 首先在工具箱中选中铅笔,然后在画布上拖曳鼠标,就可以画出线条了,还可以在颜色板上选择其它颜色画图,鼠标左键选择的是

前景色,右键选择的是背景色,在画图的时候,左键拖曳画出的就是前 景色,右键画的是背景色。 选择刷子工具,它不像铅笔只有一种粗细,而是可以选择笔尖的大小和形状,在这里单击任意一种笔尖,画出的线条就和原来不一 样了。 图画错了就需要修改,这时可以使用橡皮工具。橡皮工具选定后,可以用左键或右键进行擦除,这两种擦除方法适用于不同的情况。左键擦除是把画面上的图像擦除,并用背景色填充经过的区域。试验一下就知道了,我们先用蓝色画上一些线条,再用红色画一些,然后选择橡皮,让前景色是黑色,背景色是白色,然后在线条上用左键拖曳,可以看见经过的区域变成了白色。现在把背景色变成绿色,再用左键擦除,可以看到擦过的区域变成绿色了。 现在我们看看右键擦除:将前景色变成蓝色,背景色还是绿色,在画面的蓝色线条和红色线条上用鼠标右键拖曳,可以看见蓝色的线条被替换成了绿色,而红色线条没有变化。这表示,右键擦除可以只擦除指定的颜色--就是所选定的前景色,而对其它的颜色没有影响。 这就是橡皮的分色擦除功能。 再来看看其它画图工具。 是“用颜料填充”,就是把一个封闭区域内都填上颜色。 是喷枪,它画出的是一些烟雾状的细点,可以用来画云或烟 等。

CAD绘图教程及案例_很实用

CAD 绘制三维实体基础 AutoCAD除具有强大的二维绘图功能外,还具备基本的三维造型能力。若物体并无复杂的外表曲面及多变的空间结构关系,则使用AutoCAD可以很方便地建立物体的三维模型。本章我们将介绍AutoCAD 三维绘图的基本知识。 11.1 三维几何模型分类 在AutoCAD中,用户可以创建3种类型的三维模型:线框模型、表面模型及实体模型。这3种模型在计算机上的显示方式是相同的,即以线架结构显示出来,但用户可用特定命令使表面模型及实体模型的真实性表现出来。 11.1.1线框模型(Wireframe Model) 线框模型是一种轮廓模型,它是用线(3D空间的直线及曲线)表达三维立体,不包含面及体的信息。不能使该模型消隐或着色。又由于其不含有体的数据,用户也不能得到对象的质量、重心、体积、惯性矩等物理特性,不能进行布尔运算。图11-1显示了立体的线框模型,在消隐模式下也看到后面的线。但线框模型结构简单,易于绘制。 11.1.2 表面模型(Surface Model) 表面模型是用物体的表面表示物体。表面模型具有面及三维立体边界信息。表面不透明,能遮挡光线,因而表面模型可以被渲染及消隐。对于计算机辅助加工,用户还可以根据零件的表面模型形成完整的加工信息。但是不能进行布尔运算。如图11-2所示是两个表面模型的消隐效果,前面的薄片圆筒遮住了后面长方体的一部分。 11.1.3 实体模型 实体模型具有线、表面、体的全部信息。对于此类模型,可以区分对象的内部及外部,可以对它进行打孔、切槽和添加材料等布尔运算,对实体装配进行干涉检查,分析模型的质量特性,如质心、体积和惯性矩。对于计算机辅助加工,用户还可利用实体模型的数据生成数控加工代码,进行数控刀具轨迹仿真加工等。如图11-3所示是实体模型。 图11-1 线框模型 图11-2 表面模型 1、三维模型的分类及三维坐标系; 2、三维图形的观察方法; 3、创建基本三维实体; 4、由二维对象生成三维实体; 5、编辑实体、实体的面和边;

《画图软件画图忙》教学设计

《画图软件画图忙》教学设计 [教学目标] (1)学习启动与退出“画图”程序。 (2)了解“画图”窗口的组成,特别是画图窗口独特的组成部分。 (3)学生通过自主探索初步认识绘图工具箱。 (4)通过对画图作品的欣赏和对画图程序的简单操作,培养学生对电脑画图的兴趣,从而进一步培养对信息技术的热爱。 [教学重点与难点] 重点:培养良好的画图习惯,能正确使用撤消和擦除。 难点:读懂对话框,学会保存作品。 [课时安排] 1课时。 [教学准备] 多媒体网络教室、多媒体课件 [教学过程] 一、激趣导入 师:今天,老师给大家带来了一位美术高手,但他不用纸笔,而是用电脑画画,想不想看他的精彩表演? 播放《用“画图”画跑车》视频(2分钟)。

师:这位高手厉害不厉害?我们班有没有人能做到?想不想学? 师:想成为高手可不是一朝一夕的事儿,我们要一点一滴地学习。首先,需要有敏锐的观察力。所以,我要考考大家,刚才视频中的高手是用哪个软件完成这幅图画的? 师:看!这就是windows操作系统自带的“画图”程序。今天我们就来认识这个新朋友——“画图”。(板书课题) 二、教学新课 (一)启动“画图” 1.大家想认识这位新朋友吗?请你到电脑里把它找出来。 2.交流:你是如何找到这位新朋友的? 3.是啊,联系以前学过的打开“写字板”的方法,同学们很快就找到了,这种知识迁移的方法是我们学习新知识的一种重要的方法。 (二)“画图”窗口 1.同学们都成功的启动了画图,看看这位新朋友,结合写字板,它窗口的哪些组成部分你认识呢? 2.教师结合“写字板”引导小结。 常规部分:标题栏、菜单栏、状态栏 独特组成:工具箱、颜料盒、画图区 3.画图窗口中画图区就是我们用来画画的纸,我觉得这张纸太小了,你能帮我变大些吗?

50款医学软件

一、PPT模板与软件: 1.ScienceSlides: ScienceSlides是一种PPT插件,可方便的画出各种细胞器化学结构,用来论文画图确实很好用。特别是用这个和AI(illustrator)结合,画的图可以媲美老外的CNS哦。 2.科研医学美图PPT模板 3.200+套绝美PPT模板 二、代谢与信号分析软件: 1.CellNetAnalyzer: CellNetAnalyzer,是一种细胞网络分析工具,前身是FluxAnalyzer,是基于MatLab的代谢网络和信号传导网络分析模块,。这是一个典型的代谢流分析工具,可以进行代谢流的计算、预测、目标函数的优化,端途径分析、元素模式分析,以及代谢流之间的对比等。可以基本满足研究一个中型代谢网络的结构尤其是计算流分配的要求,大部分论文中的代谢网络分析都是或明或暗的用这个分析的。

2. 信号通路图汇总 3. 药理学思维导图 三、二维、三维构图软件: 1.DeepViewer _4.10_PC DeepViewer ,曾经也叫做Swiss-PdbViewer,是一个可以同时分析几个蛋白的应用程序。为了结构比对并且比较活性位点或者任何别的相关部分,蛋白质被分成几个层次。氨基酸突变,氢键,原子间的角和距离在直观的图示和菜单界面上很容易获得。 2.pymol-0_99rc6-bin-win32 PyMOL是一个开放源码,由使用者赞助的分子三维结构显示软件。PyMOL适用于创作高品质的小分子或是生物大分子(特别是蛋白质)的三维结构图像。PyMOL的源代码目前仍可以免费下载,供使用者编译。对于Linux、Unix以及Mac OS X等操作系统,非付费用户可以通过自行编译源代码来获得PyMOL执行程式;而对于Windows的使用者,如果不安装第三方软件,则无法编译源代码。 四、分子生物学软件

Matlab绘图教程(大量实例PPT)

MATLAB绘图

二维数据曲线图 p plot函数的基本调用格式为: x,y) ) plot( plot(x,y 其中x和y为长度相同的向量,分别用于存储x坐标和y坐标数据。 数据 例1 在0≤x2π区间内,绘制曲线y=2e-0.5x cos(4πx) 1≤区间内绘制曲线205x(4) 程序如下: x=0:pi/100:2*pi; cos(4*pi*x); 0.5*x).*cos (4*pi*x); y=2*exp(--0.5*x).* y=2*exp( x,y)) plot(x,y plot(x y plot( x y)

例2 绘制曲线。 绘制曲线 程序如下: t=0:0.1:2*pi; x=t.sin(3t); x=t*sin(3*t); y=t.*sin(t).*sin(t); plot( x,y);); plot(x,y

数最简单的调用格式是包含个输参数plot函数最简单的调用格式是只包含一个输入参数:p() plot(x) 在这种情况下,当x是实向量时,以该向量元素的下标为横坐标,元素值为纵坐标画出条连续曲线,标为横坐标,元素值为纵坐标画出一条连续曲线,这实际上是绘制折线图。

绘制多根二维曲线 1.plot函数的输入参数是矩阵形式时 数的输参数是矩阵形式时 (1) 当x是向量,y是有一维与x同维的矩阵时,则绘制出多根不同颜色的曲线。曲线条数等于y矩阵的另一维数,x被作为这些曲线共同的横坐标。 (2) 当x,y是同维矩阵时,则以x,y对应列元素为横、 纵坐标分别绘制曲线,曲线条数等于矩阵的列数。纵坐标分别绘制曲线曲线条数等于矩阵的列数

蛋白质作图软件pymol教程 Pymol学习笔记

B2WS-6JGH-PV7G-PBKP 什么是结构生物学 结构生物学(Structural biology)是生物领域里面相对较新的一个分支。它主要以生物化学和生物物理学方法来研究生物大分子,特别是蛋白质和核酸,的三维结构,以及与结构相对应的功能。因为几乎所有的细胞内的生命活动都是通过生物大分子来完成的,并且这些大分子完成这些功能的前提是它们必须具有特定的三维结构,因此,对于生物化学家们,这是一个非常具有吸引力的领域。 该领域通常被认为开始于20世纪50年代,Max Perutzhe和Sir John Cowdery Kendrew于1959年各自利用X射线晶体学方法解析了肌红蛋白(Myoglobin)的三维结构,一种在肌肉中运输氧气的蛋白。他们因此分享了1962年的诺贝尔化学奖,并由此揭开了结构生物学的序幕。截止到2008年10月28日,已有53917个生物大分子结构在https://www.doczj.com/doc/0d16909111.html, (蛋白质数据库)登记在案。 目前用于研究生物大分子结构的常用方法有X射线晶体学(X-ray crystallography)、核磁共振(NMR)、电子显微学(electron microscopy)、冷冻电子显微学(electron cryomicroscopy = cryo-EM)、超快激光光谱(ultra fast laser spectroscopy)、双偏振极化干涉(Dual Polarisation Interferometry)以及圆二色谱(circular dichroism)等。当中又以X射线晶体学和核磁共振最为常用。 图一:肌红蛋白(Myoglobin)的三维结构,世界上第一个由X射线晶体学解出的蛋白质结构,该蛋白在肌肉中传输氧气。

GRADS绘图实例教程

500mb高度场等直线图 .gs文件 * * Draw the COR.COEF SST and nhc000 * 'reinit' 'enable print h9601.31' 'clear' 'open hs.ctl' 'set dfile 1' 'set vpage 0.5 10. 0.2 8.5' 'set lon 0. 360.' 'set lat -90. 90.' 'set mproj latlon' 'set mpdset mres' 'set poli off' 'set ylint 10.' 'set xlint 20.' 'set csmooth on' 'set csmooth on' 'set csmooth on' 'set csmooth on' 'set csmooth on' 'set csmooth on' 'set csmooth on' 'set csmooth on' 'set clopts -1 -1 0.06' 'set clab forced' 'set cint 40.' 'set gxout contour' 'set cthick 4' 'set grads off' 'd rsst55' 'set string 3 c 5 0' 'set strsiz 0.14' 'draw string 4.5 7.5 1996.1.31 Global 500mb Geopotential Height Field' 'print' pull dummy .ctl文件 DSET h9601.31a TITLE height FORMAT yrev UNDEF -9999.00

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