扑克牌问题的数学推广与解决

首先给出由—扑克牌游戏规则产生的问题,进而利用(0,1)-矩阵方法对此问题作了数学推广与理论分析：即重排数g(m,n)及其存在性,最后给出g(m,n)求解算法与求解公式。     

真与雅:贾宝玉之女子审美观

贾宝玉所生活的大观园里,美女如云,虽然她们容貌不同,性情有别,但在贾宝玉的审美观中,真与雅构成了他女子审美的真正核心与共同标准.     

Introducing grapheme-phoneme correspondences (GPCs): exploring rate and complexity in phonics instruction for kindergarteners with limited literacy skills

Two experiments explored rates for introducing grapheme-phoneme correspondences (GPCs) and the types of correspondences taught for optimal alphabet and early literacy skills learning. In both studies, children entered with minimal alphabet knowledge and were randomly assigned within classrooms to one of two treatments delivered individually over 5 weeks. In Study 1, children grades K-1 were assigned to instruction in a set of either 10 (Slow rate, n?=?33) or 15 (Fast rate, n?=?32) single- and two-letter GPCs. Study 1 findings indicated that children who learned five added GPCs did not reduce learning of the common set of 10 learned GPCs for any measure (including letter names, sounds, letter sound writing, word reading, and spelling), and learning favored Fast items over Slow for letter sounds, letter sound writing, and word reading (median d?=?0.30). In Study 2, kindergarteners were assigned to instruction in either single letters only (Single, n?=?30) or mixed-size GPCs (Mixed, n?=?31). Instruction included application of GPCs to decoding and spelling. Results showed that kindergarteners in the Mixed condition made significantly greater gains learning the four two-letter GPCs across measures (median d?=?0.86), and no significant differences between groups on measures of the 11 one-letter GPCs common to both conditions. Findings add precision to understanding how rate and order of introducing GPCs influence children’s initial alphabet learning. Further study of empirically validated methods of alphabet instruction may benefit in particular those children most at risk for acquiring this foundational knowledge.

     

Elegant and Democratic Values: How Will the New English Universities Gel?

This paper examines the respective cultures of universities and polytechnics under the former 'binary' system and goes on to consider the implications of this pattern for the development of the new unitary system. It is concluded that a 'plurality of missions and cultures' will emerge alongside the movement for an elite to a mass higher education system. The importance of a concern for quality in the learning experience of students and what this should mean in practice is put forward as a unifying factor in this diversity.     

Resistance to extinction: contingency termination and generalization decrement

We present an algebraic model of resistance to extinction that is consistent with research on resistance to change. The model assumes that response strength is a power function of reinforcer rate and that extinction involves two additive, decremental processes: (1) the termination of the reinforcement contingency and (2) generalization decrement resulting from reinforcer omission. The model was supported by three experiments. In Experiment 1, 4 pigeons were trained on two-component multiple variable-interval (VI) 60-sec, VI 240-sec schedules. In two conditions, resistance to change was tested by terminating the response-reinforcer contingency and presenting response-independent reinforcers at the same rate as in training. In two further conditions, resistance to change was tested by prefeeding and by extinction. In Experiment 2, 6 pigeons were trained on two-component multiple VI 150-sec schedules with 8-sec or 2-sec reinforcers, and resistance to change was tested by terminating the response-reinforcer contingency in three conditions. In two of those conditions, brief delays were interposed between responses and response-independent reinforcers. In both Experiments 1 and 2, response rate was more resistant to change in the richer component, except for extinction in Experiment 1. In Experiment 3, 8 pigeons were trained on multiple VI 30-sec, VI 120-sec schedules. During extinction, half of the presentations of each component were accompanied by a novel stimulus to produce generalization decrement. The extinction data of Experiments 1 and 3 were well described by our model. The value of the exponent relating response strength and reinforcement was similar in all three experiments.     

Munchausen by proxy: a case, chart series, and literature review of older victims

The history of an older child victim of Munchausen by proxy (MBP) is described. He was referred for evaluation after repeated sinus surgeries for recurrent sinus infections believed to be related to a falsified history of an immunodeficiency. The perpetrator was the mother of this 14-year-old victim, consistent with the majority of such cases. This case prompted a review of cases of MBP in older children reported in our hospital as well as a literature search for other cases in older children. METHODS: This study was a chart review of children over 6 years of age who had been evaluated by social services at the Children's Hospital at the Cleveland Clinic and reported as cases of Munchausen by proxy to Child Protective Services between January 2001 and June 2003. Also, an OVID, Psychline, and Pubmed literature review of published cases of Munchausen by proxy were identified, and cases occurring in the older child were selected for review. RESULTS: Older children who are the victims of Munchausen by proxy may have an induced illness, but falsified reports of symptoms and medical history to coerce the child to undergo medical procedures may be more common. Collusion of the victim with the perpetrator may also become a factor as the child ages and adopts the deception. Given the complex relationship that exists between the parent and child, it is difficult to predict whether the victim either will assist the caregiver in maintaining the factitious illness or be able to recognize the falsification. CONCLUSIONS: Older children who are the victims of Munchausen by proxy may fear consequences of revealing the factitious illness. Physicians must consider the possibility of this diagnosis whenever there are discrepancies in a child's illness that makes a factitious illness a consideration.     

Trials to criterion: a within‐program prediction of post‐program generalization

Data‐based instruction is an important and effective procedure when teaching handicapped learners; at present, however, no validated decision rules are available to predict post‐program generalization. This study investigated the extent to which learning set analysis of a severely handicapped subject's performance was capable of providing decision rules when teaching for a generalized outcome. Generalized compliance was trained and training data analyzed to determine how data trends across training examples compared with post‐program generalization. Results show that the greatest generalization effect occurrred when training data trends were steepest downwards. Discussion of the findings includes suggestions concerning future research to further define the parameters of decision rules necessary to teach for generalization.     

Beyond phonics: Integrated decoding and spelling instruction based on word origin and structure

In this paper, the relevance of word structure knowledge to decoding and spelling instruction is discussed. An explicit, discussion oriented, direct approach to teaching decoding and spelling based on word origin and structure results in improved reading and spelling. This instruction leads students to a comparison and contrast of letter-sound correspondences, syllable patterns, and morpheme patterns in English words of Anglo-Saxon, Romance, and Greek origin.     

Learning to read: Evidence on the distinction between decoding and comprehension skills

The paper focuses on the importance of distinguishing between decoding and comprehension skills in reading. This distinction can also be applied to the study of precursors of reading and of the first phases of reading acquisition. The reconsideration of a 15-year research program shows evidence and implications of such a dissociation. In particular, the paper reviews psychometric research concerning reading performance in first and second grade, research on precursors of reading, the effects of early programs devoted to develop reading abilities. Decoding and comprehension reading components appear at least partially separated, related to different underlying cognitive abilities, differently sensitive to enrichment programs.     

探索、归纳与推广

就一道全国中竞赛题，先探索其结果，再归纳其系数规律得出几个新的结论，从而将原题加以推广。     

湍流大气中SHG光束和EHG光束的M~2因子的比较

基于广义的惠更斯-菲涅尔原理和Wigner分布函数(WDF)二阶矩的定义,对常规厄米-高斯(SHG)光束和复宗量厄米-高斯(EHG)光束通过湍流大气的M2因子和相对M2因子进行了对比分析.结果表明,大气湍流中在相同条件下的SHG和EHG光束的M2因子存在明显的差异,仅有阶数m=0、m=1时SHG和EHG光束的M2因子的相等,当m≥2时,EHG光束的M2因子比SHG光束显著小,但SHG光束的相对M2因子比EHG光束的显著小,说明SHG光束比EHG光束受湍流大气影响更小.     

Sex-related differences in response to practice on a visual-spatial test and generalization to a related test

93 first graders (mean age 6.5 years) were given a pretest and posttest on half of the items from the Children's Embedded Figures Test. Half of the children were randomly assigned to a training condition and received a brief training procedure on visual-spatial disembedding prior to the administration of the posttest. Children in the control condition received no training. The performance of girls improved significantly more from pretest to posttest than the performance of boys. Boys and girls showed similar beneficial effects of training in addition to the benefit of direct practice. The tendency that was observed for boys to perform higher than girls on the pretest, p less than .10, was not evident on the posttest. Scores on the pretest predicted scores on a different measure of visual-spatial ability only for children in the control group. The results are interpreted in terms of current theories of sex differences in visual-spatial perception.     

Predicting children’s academic achievement from early assessment scores: a validity generalization study

Although there have been numerous studies investigating the predictive validity of early assessment, observed predictive validity coefficients across studies are not stable. A validity generalization study was conducted in order to answer the question of whether the relationship between early assessment of children and later achievement is generalizable or situation-specific. This study examined 716 predictive correlation coefficients from 44 studies using Hierarchical Linear Modeling (HLM). The findings of this study revealed that predictive validity of early assessment is not generalizable. Additional analyses indicated that predictive validity differ across assessments as a function of test type, specific construct being assessed, length of prediction, and administration procedures. The most impressive finding in this study was the variability of effect sizes across different test administration types. In particular, tests that were scored through ratings were found to be most effective. These findings suggest that instead of addressing a broad predictive validity between a test and a criterion measure, it is necessary to understand early assessment procedures as a whole system by including considerations of various variables related to testing conditions.     

Classroom applications of mnemonic instruction: acquisition, maintenance, and generalization.

This investigation evaluated the effectiveness of classroom mnemonic instruction of science content, for 19 students with mild disabilities. Students were given either mnemonic instruction or more traditional instruction in a within-subjects design, in which treatment order was counterbalanced across classrooms, for each of two weekly units in life science. Following a third week of mnemonic instruction, students were taught to generate and draw their own mnemonic pictures. Results suggested that mnemonic instruction resulted in substantial increases in initial content acquisition, and substantially higher delayed-recall scores, over more traditional instructional procedures. Further, it was found that trained students were able to successfully generate and apply their own mnemonic strategies to novel content. Students overwhelmingly preferred mnemonic instruction over traditional instructional methods.     

Developing functional requesting: acquisition, durability, and generalization of effects.

This study investigated the effects of a language program called the missing-item format, on the acquisition of requesting during snack periods. The missing-item format, an assessment and training approach, develops a child's spontaneous requesting skills in everyday tasks. Generalization and response-durability measures were also collected. The missing-item format produced effects in requests for targeted snack items, but not for the majority of generalization and durability measures. A generalization training program was then implemented, using the missing-item format. As a result, a requesting repertoire that was durable and generalized across multiple settings and stimulus conditions was established in both students.     

Dyadic analyses of friendship in a sample of preschool-age children attending Head Start: correspondence between measures and implications for social competence

Friendships among a large sample of preschool-age children (N = 471) attending Head Start were assessed. Based on sociometric data, friendship dyads were identified as reciprocated (mutual choice) or nonreciprocated (unilateral choice). Dyads were further classified with respect to gender composition as either same- or mixed-gender dyads. Older children were more likely to participate in a reciprocated friendship than were younger children and reciprocated dyads were more likely to be same-gender than were nonreciprocated dyads. Analyses of interaction between dyad partners revealed that reciprocated friends interacted more frequently across all categories of interaction coded and looked at each other more frequently than did members of nonreciprocated dyads. For the positive interaction subscore, the friendship status effect was modified by a significant interaction with gender composition such that significant effects of friendship status were obtained only for same-gender dyads. Additional analyses indicated that the average social competence level was greater for reciprocated dyads than for nonreciprocated dyads. The findings suggest that reciprocated friendships are meaningful for preschool-age children and may serve as special socialization contexts in which the repertoire of behavior can be exercised and perhaps improved. They also highlight the salience of same-gender friendships in the preschool classroom.     

清新淡雅：一抹明丽温润的色彩——莫友芝山水田园诗创作特点探析

莫友芝是晚清宋诗派代表诗人,其诗以＂酸涩＂之风著称,既以学问入诗,又发乎真情。难得的是,在他的《郘亭诗钞》中,有一部分清新淡雅的山水田园诗,如一抹明丽温润的色彩,令人心旷神怡。探析其山水田园诗的创作特点,可对莫友芝的诗歌创作特点有更为全面的了解。