A Talk-Listen-Ack Beaconing Strategy for Neighbor Discovery Protocols in Wireless Sensor Networks

Neighbor discovery is a fundamental function for sensor networking. Sensor nodes discover each other by sending and receiving beacons. Although many time-slotted neighbor discovery protocols (NDPs) have been proposed, the theoretical discovery latency is measured by the number of time slots rather than the unit of time. Generally, the actual discovery latency of a NDP is proportional to its theoretical discovery latency and slot length, and inversely proportional to the discovery probability. Therefore, it is desired to increase discovery probability while reducing slot length. This task, however, is challenging because the slot length and the discovery probability are two conflicting factors, and they mainly depend on the beaconing strategy used. In this paper, we propose a new beaconing strategy, called talk-listen-ack beaconing (TLA). We analyze the discovery probability of TLA by using a fine-grained slot model. Further, we also analyze the discovery probability of TLA that uses random backoff mechanism to avoid persistent collisions. Simulation and experimental results show that, compared with the 2-Beacon approach that has been widely used in time-slotted NDPs, TLA can achieve a high discovery probability even in a short time slot. TLA is a generic beaconing strategy that can be applied to different slotted NDPs to reduce their discovery latency.

Enhancement of loudness discrimination acuity for self-generated sound is independent of musical experience

Musicians tend to have better auditory and motor performance than non-musicians because of their extensive musical experience. In a previous study, we established that loudness discrimination acuity is enhanced when sound is produced by a precise force generation task. In this study, we compared the enhancement effect between experienced pianists and non-musicians. Without the force generation task, loudness discrimination acuity was better in pianists than non-musicians in the condition. However, the force generation task enhanced loudness discrimination acuity similarly in both pianists and non-musicians. The reaction time was also reduced with the force control task, but only in the non-musician group. The results suggest that the enhancement of loudness discrimination acuity with the precise force generation task is independent of musical experience and is, therefore, a fundamental function in auditory-motor interaction.

Do no harm in due process – a historical analysis of social determinates of institutionalization in the USA

Involuntary hospitalization has been a fundamental function of psychiatric care for mentally ill persons in the USA for centuries. Procedural and judicial practices of inpatient psychiatric treatment and civil commitment in the USA have served as a by-product of socio-political pressures that demanded constant reform throughout history. The origin of modern commitment laws can best be understood through the lens of cultural paradigms that led to their creation and these suggest caution for future legislative amendments.

Hippocampus and striatum encode distinct task regularities that guide human timing behavior

The brain encodes the statistical regularities of the environment in a task-specific yet flexible and generalizable format. How it does so remains poorly understood. Here, we seek to understand this by converging two parallel lines of research, one centered on striatal-dependent sensorimotor timing, and the other on hippocampal-dependent cognitive mapping. We combined functional magnetic resonance imaging (fMRI) with a visual-tracking and time-to-contact (TTC) estimation task, revealing the widespread brain network supporting sensorimotor learning in real-time. Hippocampal and caudate activity signaled the behavioral feedback within trials and the improvements in performance across trials, suggesting that both structures encode behavior-dependent information rapidly. Critically, hippocampal learning signals generalized across tested intervals, while striatal ones did not, and together they explained both the trial-wise performance and the regression-to-the-mean biases in TTC estimation. Our results suggest that a fundamental function of hippocampal-striatal interactions may be to solve a trade-off between specificity vs. generalization, enabling the flexible and domain-general expression of human timing behavior broadly.

Zebra Crossing Detection and Time Scheduling Accuracy, Enhancement Optimization Using Artificial Intelligence

Zebra crossing detection is a fundamental function of the electronic travel aid. It can locate the zebra crossing and estimate its direction to help the visually impaired to cross the road safely. In contrast to the conventional methods, a regression approach is adopted to detect zebra crossing based on convolutional neural networks. Specifically, a fixed‐size window slides across the image captured at the intersection. The image patches are sequentially fed to the logistic regression model to identify the zebra crossing. Then the image patch of zebra crossing is fed to the regression model to predict the direction. The parameters of models are optimized by the ANN back propagation algorithm before predictions. Compared with existing methods, the proposed method can improve the precision‐recall performance of the zebra crossing identification and reduce the root mean square error of predicted directions.

التغيير في معنى المفرد والجمع في القرآن الكريم / Changes in Lexical Meaning of Singular and Plural Words in the Quran

حاولت هذه الدراسة الكشف عن أسرار استعمال المفرد والجمع في غير معناهما الأصلي في القرآن الكريم، وتتكون قضية هذه الدراسة مجيئ استعمال المفرد والجمع في غير معناهما الأصلي في القرآن الكريم، والأسرار البلاغية في مجيء المفرد والجمع خارجاً عن معناهما الأصلي في القرآن الكريم وأمّا نوع البحث المستخدم في هذه الدراسة فهو البحث الوصفي النوعي وطريقة جمع البيانات من خلال الدراسة التوثيقية لأنها من ضمن البحوث المكتبية، وتحليل البيانات عن طريقة تحليل فني بلاغي على أساس المنطق الاستقرائي. ونتيجة البحث تشير إلى مجيئ استعمال المفرد والجمع في غير معناهما الأصلي في عدة آيات قرآنية؛ لأن التنوع في استعمال المفرد والجمع يؤدي وظائف أساسية في الخطاب القرآني. الأسرار البلاغية أو الدلالات البلاغية في استعمال الجمع عن المثنى والمفرد تأتي للتعميم، والمبالغة، والتكثير والتعظيم واستعمال المفرد عن الجمع يفيد التقليل والتصغير والتحقير والتوبيخ، وقد يفيد المبالغة والإيجاز ورعاية الفاصلة. والمستفاد من هذه الدراسة نلاحظ أن القرآن الكريم يتوجه بالمتلقي إلى التأثير السريع والمباشر، وهذا منسجم مع الفكرة الإنسانية التي يخاطبها ليخدم الهدف من تنزيله من عند رب كريم رؤوف بعباده يهدف إلى هدايتهم للإيمان والتصديق بأقصر الطرق. الكلمات المفتاحية: استعمال الجمع، استعمال المفرد، الأسرار البلاغيةAbstract:This study aims to uncover the wisdom of using singular (mufrad) and plural (jamak) words that violate its original meaning. The research problem consists of two questions: what are the use of singular and plural words that violate the original meaning of the Qur'an? What is the wisdom and secret behind the use of singular and plural words that violate its original meaning in the Qur'an? The type of research is qualitative descriptive, the data collection method is library research and the data analysis used language arts (balaqhah) analysis. The results show that the use of singular and plural words that violate its original meaning is found in the Qur'anic clauses. The variety use of singular and plural is a fundamental function of the Quranic language. The wisdoms and connotations balaqhah, the use of plural mean mutsanna' (two) and singular denote common, exaggerated (hyperbola), many, and admirable meanings, whereas the use of a single word meaning plural indicates little, contempt, ostracize, humiliation, ridicule or criticisms and sometimes indicate excessive, concise and adaptable meaning. The implication of this study is that the Qur'an has a direct effect on its readers and listeners. This is in line with the human mind as the target, to implement the purpose of the Qur'an revealed by Allah SWT, to give guidance to people so they can quickly believe.

Interaction of surface pattern and contour shape in the tilt after effects evoked by symmetry

Integration of multiple properties of an object is a fundamental function of the visual cortex in object recognition. For instance, surface patterns and contour shapes are thought to be crucial characteristics that jointly contribute to recognition. However, the mechanisms of integration and corresponding cortical representations have not been fully clarified. We investigated the integration of surfaces and shapes by examining the tilt after effects (TAEs) evoked by the symmetry of patterns and contours. As symmetry in both pattern and contour evokes TAEs, we can directly measure the interaction between the two. The measured TAEs exhibited mutual transfer between the symmetry of the pattern (SP) and that of the contour shape (SS), i.e., adaptation by SP (SS) evoked TAEs when tested by SS (SP), suggesting the existence of an integrated representation. Next, we examined the interaction between SP and SS when both were simultaneously presented in adaptation. Congruent adaptors wherein their symmetry axes aligned evoked compressive interaction, whereas incongruent adaptors wherein the axes of SP and SS tilted to the opposite directions evoked subtractive interaction. These results suggest the existence of a cortical representation that integrates the properties of the surface and shape with suppressive interactions, which can provide crucial insights into the formation of object representation as well as the integration of visual information in the cortex.

Stringent Primer Termination by an Archaeo-Eukaryotic DNA Primase

Priming of single stranded templates is essential for DNA replication. In recent years, significant progress was made in understanding how DNA primase fulfils this fundamental function, particularly with regard to the initiation. Equally intriguing is the unique property of archeao-eukaryotic primases to terminate primer formation at a well-defined unit length. The apparent ability to “count” the number of bases incorporated prior to primer release is not well understood, different mechanisms having been proposed for different species. We report a mechanistic investigation of primer termination by the pRN1 primase from Sulfolobus islandicus. Using an HPLC-based assay we determined structural features of the primer 5′-end that are required for consistent termination. Mutations within the unstructured linker connecting the catalytic domain to the template binding domain allowed us to assess the effect of altered linker length and flexibility on primer termination.

From Progressive Radicalism to Democratic Degeneration: The Trajectory of John Locke's Political Theory

As an organic intellectual of the emerging propertied class in 17th century England, John Locke has made an enduring contribution to the prevailing ideas shaping the socio-political order in Western societies and beyond. Through invoking the law of nature and natural rights which were nothing more than what he had abstracted from the socio-economic conditions of the seventeenth century and had projected back into the state of nature, Locke assiduously embarked on justifying the separation of civil society from the state, naturalizing class inequalities identifying the preservation of property as the fundamental function of the state, and rationalizing the subordination of propertyless classes to the emerging liberal democratic political order geared to preserve the interests of economically hegemonic classes.

Introduction

In his book, Creation and Anarchy, Georgio Agamben writes that ‘it is … worth reflecting on the fundamental function that modal verbs develop in our culture and in philosophy in particular’.1 Agamben has in mind the modal verb ‘to be able to’ which he links to Aristotelean conception of potential (...