Currently , large - scale distributed systems generally use three - tier client / server computing model based on middelware . in this pattern , developers could concentrate on business logic programming , and let those numerous complexions such as network programming , or distributed transaction maintaining , etc . be implemented by the lower middleware 在這種計(jì)算模式下,系統(tǒng)的復(fù)雜應(yīng)用需求集中體現(xiàn)在位于服務(wù)器端的業(yè)務(wù)邏輯功能實(shí)現(xiàn)上;基于中間件技術(shù),分布式系統(tǒng)的開(kāi)發(fā)人員能夠擺脫傳統(tǒng)的網(wǎng)絡(luò)編程以及維護(hù)分布事務(wù)完整性等的繁瑣局面,直接針對(duì)業(yè)務(wù)邏輯功能進(jìn)行實(shí)現(xiàn)。
It effectively separate logic programming from interface design . moreover , the system combines web services to struts frame . in realization of web services , the system make use of axis which is most extensible and completely opened soap engine 在系統(tǒng)設(shè)計(jì)上,采用了基于mvc模式的struts框架,有效地實(shí)現(xiàn)了界面設(shè)計(jì)和邏輯編程的分離;并把webservices應(yīng)用到struts框架中,實(shí)現(xiàn)服務(wù)流程自動(dòng)化;在web服務(wù)實(shí)現(xiàn)上,采用了擴(kuò)展性最強(qiáng)、完全開(kāi)放和可插入體系結(jié)構(gòu)的引擎axis 。
The dcs of i / a series is regarded as main reference object , and the control is separated from model . and the configuration of control is operatised at administration system , not to be added into model , not to build control sound code also . therefore it realizes on - line adjusting , real - time control and so on . users configurate by filling table . they only define i / o condition , fill certain operation variable , and name logic variable . the software offers a friendly user ' s interface , so personnel can compile and modify the control and logic program , change the value of logic and control variable conveniently , attach themselves to run , debug and control the system , not need to know the programs deeply . so the configuration software offer a flat that control engineers can attend to control loop , not to give their attention to the complicated program 在本課題中,采用填表的方式進(jìn)行控制組態(tài),用戶只需定義i / o條件、填寫(xiě)具體的運(yùn)算變量名即可。本軟件為建模人員提供了一個(gè)友好的用戶界面,使建模人員在建模時(shí)不必對(duì)模塊內(nèi)部的控制、邏輯程序有很深的了解就可以方便的對(duì)其進(jìn)行編寫(xiě)和修改,實(shí)時(shí)改變各邏輯和控制變量在數(shù)據(jù)庫(kù)里的值,參與運(yùn)行和調(diào)試,從而實(shí)現(xiàn)對(duì)系統(tǒng)的控制。因此,本組態(tài)軟件提供的這樣一個(gè)平臺(tái),讓控制工程師能集中精力于控制回路的構(gòu)成,而不必拘泥于一些具體而煩瑣的程序操作。
With the development of science , embedded system has been widely used in the field of industrial control and intelligent appliance with increasing complication of control logic and function . as compared with the simple control logic program of the earlier embedded system , modern embedded system is inclient to integrated operation system , which makes embedded system more and more important 隨著科學(xué)技術(shù)的不斷發(fā)展,嵌入式系統(tǒng)在工業(yè)控制和智能家電領(lǐng)域得到了廣泛的應(yīng)用,同時(shí)控制邏輯和功能也變得越來(lái)越復(fù)雜,相對(duì)于早期嵌入式系統(tǒng)所采用的簡(jiǎn)單的控制邏輯程序,現(xiàn)代嵌入式系統(tǒng)越來(lái)越傾向于使用完整的操作系統(tǒng),這就使得嵌入式操作系統(tǒng)在嵌入式系統(tǒng)領(lǐng)域變得越來(lái)越重要。