分类超曲面算法是一种简单的基于覆盖的分类算法.实验证明该算法具有分类正确率高、速度快的优点.但是,关于该算法的相关理论问题需要深入研究.文中对该算法的几个相关理论问题进行了研究.首先给出并证明了在分割的最大层数给定时算法...分类超曲面算法是一种简单的基于覆盖的分类算法.实验证明该算法具有分类正确率高、速度快的优点.但是,关于该算法的相关理论问题需要深入研究.文中对该算法的几个相关理论问题进行了研究.首先给出并证明了在分割的最大层数给定时算法假设空间的VC维,在此基础上结合可能近似正确(Probably Approximately Correct,PAC)学习框架,得出了对算法样本复杂度的估计,使得分类超曲面算法保证可PAC学习到任意目标概念.其次,分析了算法的时间复杂度和空间复杂度.最后,给出了无矛盾样本集的概念,并证明当输入样本集是有限无矛盾样本集的条件下,算法一定是收敛的.展开更多
Based on some language testing theories, an analysis of an English Mid-term Examination of grade eight students of Jingzhi Middle School is made in this paper. By means of SPSS （Statistical Package for the Social Sci...Based on some language testing theories, an analysis of an English Mid-term Examination of grade eight students of Jingzhi Middle School is made in this paper. By means of SPSS （Statistical Package for the Social Sciences） statistical software, the paper makes a whole analysis of the test paper, which covers descriptive statistics, reliability, and validity. The study aims to find some problems of the test paper, teachers＇ teaching, and students＇ learning. Thus, based on the results of analysis, this paper aims to improve the quality of test papers and give some advice to language teaching展开更多
Educational achievement and age correlatives may have significant bearings on generation, maintenance, and sustenance of environment to disseminate education for comprehensive development of learners as permeation of ...Educational achievement and age correlatives may have significant bearings on generation, maintenance, and sustenance of environment to disseminate education for comprehensive development of learners as permeation of learning and its diffusion rate may vary depending upon different achievements on literacy scale for different age groups. More so, for disable learners as such learners need additional initiatives and assisting environment of even more literate fellow beings constituting surroundings. From this perspective, this paper makes a descriptive analytical effort to present census （2011） results in evaluating overall literacy position and that for disable ones alongwith environment availability through simple statistical tools展开更多
The use of mobile phone technologies in the education sector is getting more attention nowadays. This is due to the advancement of technologies equipped in majority of the mobile phones which makes the devices become ...The use of mobile phone technologies in the education sector is getting more attention nowadays. This is due to the advancement of technologies equipped in majority of the mobile phones which makes the devices become more capable of supporting the learning and teaching activities. Mobile learning （m-learning） is a learning tool which can be run on mobile devices. It can be considered as an enhancement to the electronic learning （e-learning）. M-learning overcomes several limitations of e-learning especially in term of mobility. It provides more independent way of learning whereby learners can use the application to do the learning activities at anytime and any place. However, as with other learning and teaching applications, applications to be developed for mobile learning must also be developed based on certain learning theories and guidelines in order for them to be effective as well as usable. Therefore, in this paper, the development process of a mobile learning course content application called Mobile System Analysis and Design （MOSAD） as a revision tool will be shared and its testing＇s conduct and results will also be presented and discussed. MOSAD was developed with the content of a topic from the System Analysis and Design （SAD） course conducted at Universiti Teknologi PETRONAS （UTP）. A heuristic test involving 5 experts in the area of Human Computer Interaction （HCI） were conducted after the first version of MOSAD was completed to strengthen its functionality and usability, followed by a Post Test Quasi Experimental Design which was conducted to 116 UTP second year students who took the SAD course to test the effectiveness and usability of MOSAD after it was revised. As a result from the post test, the students who had used MOSAD （66 out of the 116 students） as their revision tool for answering ten quiz questions obtained a mean score of 7.7576 as compared to 5.160 obtained by the other group of students （50 out of the 116 students） who used traditional methods of revision. Besides, usability test which tested on consistency, leamability, flexibility, minimal action and minimal memory load of MOSAD gave results above 3.5 for each metric based on the rating of 1 to 5. Thus, both results indicate that MOSAD is effective and usable as a revision tool for the higher education students.展开更多
This paper outlines the necessity of the knowledge representation for the geometrical shapes （KRGS）. We advocate that KRGS for being powerful must contain at least three major components, namely （1） fu...This paper outlines the necessity of the knowledge representation for the geometrical shapes （KRGS）. We advocate that KRGS for being powerful must contain at least three major components, namely （1） fuzzy logic scheme; （2） the machine learning technique; and （3） an integrated algebraic and logical reasoning. After arguing the need for using fuzzy expressions in spatial reasoning, then inducing the spatial graph generalized and maximal common part of the expressions is discussed. Finally, the integration of approximate references into spatial reasoning using absolute measurements is outlined. The integration here means that the satisfiability of a fuzzy spatial expression is conducted by both logical and algebraic reasoning.展开更多
Learner strategies are of crucial importance in ESL/EFL learning and teaching. The importance lies to the fact that learners are encouraged to become autonomous language learners by self-evaluating their learning and ...Learner strategies are of crucial importance in ESL/EFL learning and teaching. The importance lies to the fact that learners are encouraged to become autonomous language learners by self-evaluating their learning and self-directing the process of language development. More effective learners differ from less effective ones in that they use more strategies and in greater variety. Research shows that learner strategies can be taught and can facilitate language learning if a number of factors, such as the explicitness of the strategy instruction, the individual differences of the learners, the appropriateness of the teaching materials, the teacher training on the strategy instruction etc. should be taken into consideration.展开更多
Let D be an integral domain, ＊a star-operation on D, and S a multiplicative subset of D. We define D to be an S-＊w-principal ideal domain if for each nonzero ideal I of D, there exist an element s ∈ S and a princip...Let D be an integral domain, ＊a star-operation on D, and S a multiplicative subset of D. We define D to be an S-＊w-principal ideal domain if for each nonzero ideal I of D, there exist an element s ∈ S and a principal ideal （c） of D such that sI （c） In this paper, we study some properties of S-＊w-principal ideal domains. Among other things, we study the local property, the Nagata type theorem, and the Cohen type theorem for S-＊w-principal ideal domains.展开更多
Synthetic macrocyclic host molecules always play an essential role in the establishment and development of supramolecular chemistry. Along with the continuous interests in the study of classical macrocycles, recent de...Synthetic macrocyclic host molecules always play an essential role in the establishment and development of supramolecular chemistry. Along with the continuous interests in the study of classical macrocycles, recent decades have witnessed the emergence and rapid development of the chemistry and supramolecular chemistry of novel and functional macrocycles. Owing to their easy availability, a self-tunable V-shaped cavity resulted from 1,3-alternate conformation, and diversified electronic features steered by the interplay between heteroatom linkages and aromatic rings, heteracalixaromatics act as a type of versatile and powerful macrocyclic hosts in molecular recognition and fabrication of supramolecular systems. Very recently, by means of engineering the bond connectivity or the recombination of chemical bonds within heteracalixaromatics, we have devised coronarenes, a new generation of macrocycles. In this concise review, macrocyclic and supramolecular chemistry of coronarenes are summarized in the order of their syntheses, structural features, molecular recognition and self-assembly properties. In the last part of this article, personal perspectives on the study of macrocyclic and supramolecular chemistry will also be discussed.展开更多
文摘分类超曲面算法是一种简单的基于覆盖的分类算法.实验证明该算法具有分类正确率高、速度快的优点.但是,关于该算法的相关理论问题需要深入研究.文中对该算法的几个相关理论问题进行了研究.首先给出并证明了在分割的最大层数给定时算法假设空间的VC维,在此基础上结合可能近似正确(Probably Approximately Correct,PAC)学习框架,得出了对算法样本复杂度的估计,使得分类超曲面算法保证可PAC学习到任意目标概念.其次,分析了算法的时间复杂度和空间复杂度.最后,给出了无矛盾样本集的概念,并证明当输入样本集是有限无矛盾样本集的条件下,算法一定是收敛的.
文摘Based on some language testing theories, an analysis of an English Mid-term Examination of grade eight students of Jingzhi Middle School is made in this paper. By means of SPSS （Statistical Package for the Social Sciences） statistical software, the paper makes a whole analysis of the test paper, which covers descriptive statistics, reliability, and validity. The study aims to find some problems of the test paper, teachers＇ teaching, and students＇ learning. Thus, based on the results of analysis, this paper aims to improve the quality of test papers and give some advice to language teaching
文摘Educational achievement and age correlatives may have significant bearings on generation, maintenance, and sustenance of environment to disseminate education for comprehensive development of learners as permeation of learning and its diffusion rate may vary depending upon different achievements on literacy scale for different age groups. More so, for disable learners as such learners need additional initiatives and assisting environment of even more literate fellow beings constituting surroundings. From this perspective, this paper makes a descriptive analytical effort to present census （2011） results in evaluating overall literacy position and that for disable ones alongwith environment availability through simple statistical tools
文摘The use of mobile phone technologies in the education sector is getting more attention nowadays. This is due to the advancement of technologies equipped in majority of the mobile phones which makes the devices become more capable of supporting the learning and teaching activities. Mobile learning （m-learning） is a learning tool which can be run on mobile devices. It can be considered as an enhancement to the electronic learning （e-learning）. M-learning overcomes several limitations of e-learning especially in term of mobility. It provides more independent way of learning whereby learners can use the application to do the learning activities at anytime and any place. However, as with other learning and teaching applications, applications to be developed for mobile learning must also be developed based on certain learning theories and guidelines in order for them to be effective as well as usable. Therefore, in this paper, the development process of a mobile learning course content application called Mobile System Analysis and Design （MOSAD） as a revision tool will be shared and its testing＇s conduct and results will also be presented and discussed. MOSAD was developed with the content of a topic from the System Analysis and Design （SAD） course conducted at Universiti Teknologi PETRONAS （UTP）. A heuristic test involving 5 experts in the area of Human Computer Interaction （HCI） were conducted after the first version of MOSAD was completed to strengthen its functionality and usability, followed by a Post Test Quasi Experimental Design which was conducted to 116 UTP second year students who took the SAD course to test the effectiveness and usability of MOSAD after it was revised. As a result from the post test, the students who had used MOSAD （66 out of the 116 students） as their revision tool for answering ten quiz questions obtained a mean score of 7.7576 as compared to 5.160 obtained by the other group of students （50 out of the 116 students） who used traditional methods of revision. Besides, usability test which tested on consistency, leamability, flexibility, minimal action and minimal memory load of MOSAD gave results above 3.5 for each metric based on the rating of 1 to 5. Thus, both results indicate that MOSAD is effective and usable as a revision tool for the higher education students.
文摘This paper outlines the necessity of the knowledge representation for the geometrical shapes （KRGS）. We advocate that KRGS for being powerful must contain at least three major components, namely （1） fuzzy logic scheme; （2） the machine learning technique; and （3） an integrated algebraic and logical reasoning. After arguing the need for using fuzzy expressions in spatial reasoning, then inducing the spatial graph generalized and maximal common part of the expressions is discussed. Finally, the integration of approximate references into spatial reasoning using absolute measurements is outlined. The integration here means that the satisfiability of a fuzzy spatial expression is conducted by both logical and algebraic reasoning.
文摘Learner strategies are of crucial importance in ESL/EFL learning and teaching. The importance lies to the fact that learners are encouraged to become autonomous language learners by self-evaluating their learning and self-directing the process of language development. More effective learners differ from less effective ones in that they use more strategies and in greater variety. Research shows that learner strategies can be taught and can facilitate language learning if a number of factors, such as the explicitness of the strategy instruction, the individual differences of the learners, the appropriateness of the teaching materials, the teacher training on the strategy instruction etc. should be taken into consideration.
文摘Let D be an integral domain, ＊a star-operation on D, and S a multiplicative subset of D. We define D to be an S-＊w-principal ideal domain if for each nonzero ideal I of D, there exist an element s ∈ S and a principal ideal （c） of D such that sI （c） In this paper, we study some properties of S-＊w-principal ideal domains. Among other things, we study the local property, the Nagata type theorem, and the Cohen type theorem for S-＊w-principal ideal domains.
基金supported by the National Natural Science Foundation of China (21732004, 21421064, 91427301, 21132005)Tsinghua University
文摘Synthetic macrocyclic host molecules always play an essential role in the establishment and development of supramolecular chemistry. Along with the continuous interests in the study of classical macrocycles, recent decades have witnessed the emergence and rapid development of the chemistry and supramolecular chemistry of novel and functional macrocycles. Owing to their easy availability, a self-tunable V-shaped cavity resulted from 1,3-alternate conformation, and diversified electronic features steered by the interplay between heteroatom linkages and aromatic rings, heteracalixaromatics act as a type of versatile and powerful macrocyclic hosts in molecular recognition and fabrication of supramolecular systems. Very recently, by means of engineering the bond connectivity or the recombination of chemical bonds within heteracalixaromatics, we have devised coronarenes, a new generation of macrocycles. In this concise review, macrocyclic and supramolecular chemistry of coronarenes are summarized in the order of their syntheses, structural features, molecular recognition and self-assembly properties. In the last part of this article, personal perspectives on the study of macrocyclic and supramolecular chemistry will also be discussed.
