The buck stops here: A survey of the financial status of PhD graduate students in psychology, 1966–1987.

Results of a survey of 454 graduate PhD candidates in psychology (1966–1987) suggest that current graduate students must assume a greater proportion of the cost of their education. Several strategies for increasing graduate student stipends are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relation between ego identity and temporal perspective.

In an attempt to expand the ego identity concept of J. E. Marcia (1975) to include the area of temporal perspective, 80 male undergraduates were administered a time line developed by the present 1st author. Temporal density (percentage of experiences in each of 5 time zones), temporal extension (chronological time spans for the past, future, and overall), and perceived duration (line length for each of 5 time zones) were measured, and an identity status interview was rated with a 4-status classification system (diffusion, foreclosure, moratorium, and identity achievement). Findings show significant differences between identity groups with regard to the proportional allocation both of experiences (i.e., density) and of linear space (i.e., perceived duration) among the time zones. The achievement and foreclosure groups generally scored higher on measures of futurity than did the diffusion and moratorium groups. Results point toward the crucial importance of the contextual framework in interpreting findings regarding temporal perspective. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Panic onset and major events in the lives of agoraphobics: A test of contiguity.

Major life events were reported in greater numbers and by a higher percentage of 50 index agoraphobics during a time period around panic onset than during either a within-subjects or a between-subjects control period. These differences were found for analyses of life events in general, events that preceded panic, and foreseeable events that occurred shortly after panic onset. Though many events involved separation or interpersonal conflict, other types of events were frequently reported. Results provide more convincing evidence than prior studies of a contiguous relationship between life events and onset of panic attacks associated with agoraphobia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Children and Computers: Do Sex-Related Differences Persist?

A three-year study of middle-school and high-school students shows that girls are less interested in computers and less confident in their computer skills even when they have as much experience with the technology as boys.     

Semantic relatedness and the scope of facilitation for upcoming words in sentences.

Three experiments examined the generality of context effects displayed for congruous completions appearing in high- and low-constraint sentences. Exp 1 found an effect of context for a broader range of completions for low-constraint than high-constraint sentences. Lexical decisions for unexpected congruous words that were related in meaning to the most expected completion for the sentence showed a benefit from context in low-constraint sentences only. Unexpected words that were unrelated to the most expected completion never benefited from appearing in either high- or low-constraint sentence contexts. Exp 2 varied the semantic relatedness of the unexpected words within Ss and found that unrelated words still did not benefit from sentence context. Exp 3 included only low-constraint sentences to encourage Ss to develop broader expectations for upcoming words. Unrelated words continued not to display any benefit from context. It is concluded that the scope of facilitation for upcoming words demonstrated in a lexical decision task is wider for low-constraint than high-constraint sentences, but never includes unrelated, although acceptable, completions for the sentence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of blending high‐pressure low‐density polyethylene on the crystallization kinetics of linear low‐density polyethylene

It is well known that the addition of a small amount of high‐pressure low‐density polyethylene (HP‐LDPE) to linear low‐density polyethylene (LLDPE) can improve the optical properties of LLDPE, and LLDPE/HP‐LDPE blend is widely applied to various uses in the field of film. The optical haziness of polyethylene blown films, as a result of surface irregularities, is thought to be as a consequence of the different crystallization mechanisms. However, not much effort has been directed toward understanding the effect of HP‐LDPE blending on the overall crystallization kinetics (k) of LLDPE including nucleation rate (n) and crystal lateral growth rate (v). In this study, we investigated the effect of blending 20% HP‐LDPE on the crystallization kinetics of LLDPE polymerized by Ziegler‐Natta catalyst with comonomer of 1‐butene. Furthermore, by combining depolarized light intensity measurement (DLIM) and small‐angle laser light scattering (SALLS), we have established a methodology to estimate the lateral growth rate at lower crystallization temperatures, in which direct measurement of lateral growth by polarized optical microscopy (POM) is impossible due to the formation of extremely small spherulites. This investigation revealed that HP‐LDPE blending leads to enhanced nucleation rate, reduced crystal lateral growth rate, and a slight increase in the overall crystallization kinetics of pure LLDPE. From the estimated crystal lateral growth rate, it was found that the suppression in v from HP‐LDPE blending is larger at lower temperatures than at higher temperatures. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

A proposition of adaptive state space partition in reinforcement learning with Voronoi tessellation

This paper presents a new adaptive segmentation of continuous state space based on vector quantization algorithm such as Linde–Buzo–Gray for high-dimensional continuous state spaces. The objective of adaptive state space partitioning is to develop the efficiency of learning reward values with an accumulation of state transition vector in a single-agent environment. We constructed our single-agent model in continuous state and discrete actions spaces using Q-learning function. Moreover, the study of the resulting state space partition reveals a Voronoi tessellation. In addition, the experimental results show that this proposed method can partition the continuous state space appropriately into Voronoi regions according to not only the number of actions, but also achieve a good performance of reward-based learning tasks compared with other approaches such as square partition lattice on discrete state space.     

Conducting guided inquiry in science classes using authentic, archived, web-based data

Students are often unable to collect the real-time data necessary for conducting inquiry in science classrooms. Web-based, real-time data could, therefore, offer a promising tool for conducting scientific inquiries within classroom environments. This study used a quasi-experimental research design to investigate the effects of inquiry-based instruction coupled with archived online data. Ninety-six preservice teachers in a four-year elementary science teacher-training program participated in this study. The students were enrolled in three sections of the methods course, and these existing groups were randomly assigned to the treatment groups: traditional instruction, traditional instruction supported with a simulation, and inquiry-based instruction with archived online data. Data were collected with structured interviews and analyzed with the constant comparative method and one-way ANOVA. Before the instructional interventions, none of the participants had a scientific understanding of tides, and 15% of the participants had no conceptual understanding of tides at all. After instruction, 72% of the participants who received inquiry-based instruction with archived online data were categorized as having scientific conceptual understandings; 46% of participants who received traditional instruction supported with a simulation were categorized as having scientific conceptual understandings; and 43% of participants who received traditional instruction were categorized as having scientific conceptual understandings. Statistical analyses showed that the group receiving inquiry-based instruction with archived online data performed significantly better than the other two instructional groups. Inquiry-based instruction with archived online data can be used to effectively perform inquiry activities within science classes; it might be used at different grade levels to teach a variety of scientific content.     

Atmosphere effects on micron-sized ZnO ridges during sintering

During the fabrication of micron-sized ceramic features, sintering plays a critical role in shape retention and microstructure evolution. Because of the evaporation tendency of zinc oxide (ZnO) during sintering, atmosphere has a significant influence on the sintering behavior and feature fidelity. In this study, micron-sized ZnO ridge features were sintered under air and argon atmospheres. Ridge size, line edge roughness, and shrinkage were characterized. Sintering mechanisms and evaporation mass loss were analyzed in order to obtain fundamental understanding of the micron-sized ZnO feature sintering. Oxygen partial pressure is the deciding factor in the ridge feature evolution. The argon atmosphere leads to faster grain growth and densification but compromises the ridge size and ridge grain size due to increased mass loss.     

下雨的巴黎

正身兼设计师和手艺人两职的米歇尔(Michel Heurtault)将雨伞定义为一个兼具艺术价值和机械功能的物件,凝聚了木工、纺织、刺绣、雕塑,甚至高级定制服装等多个行业的智慧。为了一件作品的完成,常常需要借助外界的支持与协助。比如雨伞的木质伞柄就是由法国和意大利的两个木工艺者专门提供的。他的作品件件细致,全部由手工制作,尤其在细节上可见其品质的精良和设计的巧思。细观每件作品,所有微小的部件都存在它的别致之处,彰显着夺目的光辉。每把雨伞都是一个独立的生命体。