Logic programming as classical inference

We propose a denotational semantics for logic programming based on a classical notion of logical consequence which is apt to capture the main proposed semantics of logic programs. In other words, we show that any of those semantics can be viewed as a relation of the form $T{\models }^{\star }X$ where T is a theory which naturally represents the logic program under consideration together with a set of formulas playing the role of “hypotheses”, in a way which is dictated by that semantics, ${\models }^{\star }$ is a notion of logical consequence which is classical because negation, disjunction and existential quantification receive their classical meaning, and X represents what can be inferred from the logic program, or an intended interpretation of that logic program (such as an answer-set, its well-founded model, etc.). The logical setting we propose extends the language of classical modal logic as it deals with modal operators indexed by ordinals. We make use of two kinds of basic modal formulas: ${\square }_{\alpha }\phi$ which intuitively means that the logical program can generate φ by stage α of the generation process, and ${◇}_{\alpha }{\square }_{\beta }\phi$ with $\alpha >\beta$, which intuitively means that φ can be used as a hypothesis from stage β of the generation process onwards, possibly expecting to confirm φ by stage α (so expecting ${\square }_{\alpha }\phi$ to be generated). This allows us to capture Rondogiannis and Wadge's version of the well-founded semantics [27] where a member of the well-founded model is a closed atom which receives an ordinal truth value of ${\mathtt{true}}_{\alpha }$ or ${\mathtt{false}}_{\alpha }$ for some ordinal α: in our framework, this corresponds to having $T{\models }^{\star }{\square }_{\alpha }\phi$ or $T{\models }^{\star }{\square }_{\alpha }\neg \phi$, respectively, with T being the natural representation of the logic program under consideration and the right set of “hypotheses” as dictated by the well-founded semantics. The framework we present goes much beyond the proposed traditional semantics for logic programming, as it can for instance let us investigate under which conditions a set of hypotheses can be minimal, with each hypothesis being activated as late as possible and confirmed as soon as possible, setting the theoretical foundation to sophisticated ways of making local use of hypotheses in knowledge-based systems, while still being theoretically grounded in a classical notion of logical consequence.     

Mixed Generation Sensitivity Analysis: An Optimal Scenario Study

There are several generating units available to meet the load demand on any given day. The mixed‐integer programme case engages generating units that can be shut down or operated between minimum and maximum output levels within a specific time demand block. An examination of these conditions espouses the utilization of renewable energy technology as a reliable power generation source and its effectiveness and augmentation in a robust, heavily subjugated thermal generation system. The mixed‐integer problem has the predisposition to generate many subproblems during the computation. However, with careful selection of the parameters in the model, the challenges are easily overcome. Hydroelectric energy is significant from an operational standpoint as it requires little or no ramp‐up time, commonly found in many combustion technologies. The essential load‐following capability, peaking capacity and voltage stability attributes render hydroelectric energy as a significant part in ensuring reliable electricity service and in meeting customer needs in a market‐driven industry. When this renewable resource is combined with the thermal generation, an improved reliability function is apparent. Yet, in order to minimize the environmental effects inherent in this type of energy resource, the renewable power supply is expected to produce an effectual, consistent output. The integration of renewable generation within the electrical system entails intricate analysis of the transmission line upgrades throughout the system. These upgrades are designed to relieve congestion, improve reliability and provide voltage support by thoroughly evaluating the alternatives to accommodate the new expansion efforts. This paper examines the system integration of renewable generators, via simulated studies, in the context of electrical operations from the hydroelectric generation perspective. Copyright © 2014 John Wiley & Sons, Ltd.     

Manipulating number generation: Loud + long = large?

Humans make numerous choices every day and tend to perceive these choices as free. The present study shows how simple free choices are biased by experiencing unrelated auditory information. In two experiments, participants categorized tones according to their intensity on the dimensions volume and duration on the majority of trials. On some trials, however, they were to randomly generate a number, and we found these choices to be influenced by tone intensity. Particularly, if participants were cued toward volume, loud tones clearly biased participants to generate larger numbers. For tone duration, a similar effect only emerged if spatial information was reinforced by the motor context of the task. The findings extend previous findings relating to the ATOM framework (A Theory of Magnitude) by an explicit focus on auditory magnitude processing. As such, they also constrain ATOM by showing that the connections between different magnitude dimensions vary to a considerable degree.     

Negative life events and symptoms of depression and anxiety: stress causation and/or stress generation

Background and Objectives: Stressful life events are known to contribute to development of depression; however, it is possible this link is bidirectional. The present study examined whether such stress generation effects are greater than the effects of stressful life events on depression, and whether stress generation is also evident with anxiety. Design: Participants were two large age cohorts (N = 732 aged 44 years; N = 705 aged 63 years) from the West of Scotland Twenty-07 study. Methods: Stressful life events, depression, and anxiety symptoms were measured twice five years apart. Cross-lagged panel analysis examined the mutual influences of stressful life events on depression and on anxiety over time. Results: Life events predicted later depressive symptomatology (p = .01), but the depression predicting life events relationship was less strong (p = .06), whereas earlier anxiety predicted life events five years later (p = .001). There was evidence of sex differences in the extent to which life events predicted later anxiety. Conclusions: This study provides evidence of stress causation for depression and weaker evidence for stress generation. In contrast, there was strong evidence of stress generation for anxiety but weaker evidence for stress causation, and that differed for men and women.     

Research With the Draw-A-Person Test: Conceptual and Methodological Issues

A number of methodological, statistical, and conceptual problems are inherent in research with the Draw-A-Person Test (DAP). These difficulties invalidate the theoretical position that an individual's gender-role identification is reflected in the sex of the figure drawn. The complexity of these problems affects the evaluation of the DAP and illustrates the need for multiple approaches to its interpretation.     

Intergenerational Relationships Within the Local Congregation

ABSTRACT

The following article explores the effect of the quality of intergenerational relationships on the health, healing and wholeness of the congregation. The fundamental premise is that an intergenerational approach to congregational life is a conscious, intentional choice on the part of the leadership and membership of that congregation to honor both the contributions and the requirements of each and every generation for the good of that generation as well as the good of the whole community. A casestudy is presented to demonstrate this approach. A reflection on the casestudy focuses on three dimensions of this approach to building up intergenerational relationships, i.e., the revelation of 1 Corinthians 12, the approach of family systems theory, and the paradigm of pastoral care.     

押韵加工的认知神经机制

押韵是指一对词语中从最后一个发音的元音到词尾的语音结构均相同的现象。现有押韵加工主要分为押韵识别与押韵产生两个研究领域,两者的认知加工过程相似,包括字形编码、形音转换、语音表征与语音分段等阶段。从语音加工与字形加工两方面对押韵过程的神经基础进行探讨,发现左半球颞上回与额下回分别负责语音表征与语音分段,左半球梭状回参与着字形编码,而有效的形音转换依赖于左半球顶下小叶与额下回组成的神经网络。今后应进一步整合不同研究方法与任务下的研究结果,并对押韵产生加工进行更深入的探讨。     

论代际公平

公平问题是一个现代社会日益凸现的问题。如果将公平问题放在“代”的语境中加以讨论和审视 ,则可以将公平分为代内公平和代际公平。代内公平实际上就是一般所说的公平。代际公平可分为在场各代之间的公平和在场各代与后代之间的公平。由于对这两种代际公平未加区分 ,因此 ,人们在讨论代际公平问题时往往显得语义含糊。由于在场各代处于现实的关系之中 ,他们之间的公平是具有实践基础的。但是 ,对在场各代与尚未出场的人类后代之间的公平却存在着较大的争议 ,其焦点在于尚未出场的人类后代与在场各代之间的关系并不是现实的。为此 ,对在场各代与人类后代的公平进行权利论证明就是当前一个迫切的理论课题。     

Specificity and Abstraction of Examples: Opposite Effects on Fixation for Creative Ideation

Fixation is one of the major obstacles that individuals face in creative idea generation contexts. Several studies have shown that individuals unintentionally tend to fixate to the examples they are shown in a creative ideation task, even when instructed to avoid them. Most of these studies used examples formulated with high level of specificity. However, no study has examined individuals’ creative performance under an instruction to diverge from given examples, when these examples are formulated with a high level of abstraction. In the present study, we show that (a) instructing participants to avoid using common examples when formulated with a high level of specificity increases fixation; whereas (b) instructing participants to avoid such examples while using a more abstract level for stating these common examples—such as a categorization of these examples—mitigates fixation and doubles the number of creative ideas generated. These findings give new insights on the key role of categorization in creative ideation contexts.     

Enhancement of Creativity: Semantic Priming Through Naming Objects Loosens Functional Fixedness within Idea Generation

Functional fixedness is related to excessive focusing on a specific functional property of an object. We assumed that the naming of other objects which possess the same functional property to a lesser extent than a given object can reduce the excessive focusing on this functional property for this object. It can help to loosen functional fixedness and improve individual creative performance. We tested the effectiveness of this method with 302 participants aged between 17 and 22 (256 female and 46 male). The study consisted of two experiments with 110 and 192 participants, respectively. Prior to performing a creative activity (story writing in Experiment 1 and thinking up unusual uses of a given object in Experiment 2), participants from different groups were asked to name objects which possess the main functional property of the given object to the same extent, to a lesser extent, and to a greater extent, respectively. In both phases of the study, we found a significant effect on the extent of the target property possession on originality. Results showed that participants named objects with the lesser manifestation of a target property outperformed their counterparts from other groups.