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This work presents experimental results on pickup velocity (critical velocity) measurements for a variety of particulate solids. The present experiments together with previously published experiments of a number of researchers encompass about 100 measurements of 24 materials for a wide range of particle sizes, shapes and densities. Based on the experimental results, three zones are defined by establishing simple relationships between the Reynolds and Archimedes numbers. The empirical relationships were further modified by taking into account the pipe diameter and particle shape (sphericity). The three-zone model was shown to reasonably correlate to Geldart's classification groups.  相似文献   
3.
The debuggers of Ref. 11) and most of their derivatives are of themeta-interpreter type. The computation of the debugger tracks the computation of the program to be diagnosed at the level of procedure call. This is adequate if the intuitive understanding of the programmer is in terms of procedure calls; as is indeed the case in Prolog. InLDL however, while the semantics of the language are described in a bottom-up, fixpoint model of computation,8) theactual execution of a program is a complex sequence of low-level procedure calls determined (and optimized) by the compiler. Consequently, a trace of these procedure calls is of little use to the programmer. Further, one cannot “execute” anLDL program as if it was a Prolog program; the program may simply not terminate in its Prolog reading and severalLDL constructs have no obvious Prolog counterparts. We identify the origin of a fault in theLDL program by a top-down, query/subquery approach. The basic debugger, implemented in Prolog, is a shell program between the programmer and theLDL program: it poses queries and uses the results to drive the interaction with the user. It closely resembles the one presented in Ref. 11). The core of a more sophisticated debugger is presented as well. Several concepts are introduced in order to quantify debugging abilities. One is that of agenerated interpretation, in which the structureless intended interpretation of Ref. 11) is augmented with causality. Another is the (idealized) concept of areliable oracle. We show that given an incorrect program and a reliable oracle which uses a generated interpretation, a cause for the fault will be found in finitely many steps. This result carries over to the more sophisticated debugger.  相似文献   
4.
The Oslo A and B agreements of September 1993 and September 1995 were the beginning of a process aimed at a peaceful resolution of the Arab-Israeli conflict. The Israeli-Jordanian Treaty of 1994 addresses issues of water sharing between the two parties. In 1995, Israel and the Palestinians signed an Agreement on Water and Sewage as part of their Interim Agreement. In February 1996, Israel, Jordan, and the Palestinians agreed to a “Declaration of Principles for Joint Development of Water Resources.” The purpose of this paper is to compare the components of the two Agreements with an “ideal” institution for management of shared water resources. The “ideal” institution was formulated by 23 water experts who were interviewed on this issue. The main finding is that in most respects, expert opinions did not differ significantly from the Israeli-Jordanian Treaty of Peace and the Israeli-Palestinian Interim Agreement.  相似文献   
5.
This paper explores the scale and scope of transformations in the environmental planning field, and the factors that may advance or impede their widespread adoption. A conceptual model is offered which examines scope (defined as type, breadth and structure of the transformation), and the scale of its impact (categorized as stakeholder, organizational, institutional or societal) and applies it to the analysis of several cases in Israel where environmental transformations, affecting the way in which planning is conducted, have been adopted. Conclusions include identification of conditions for facilitating and advancing transformations, including knowledge of innovative alternatives, initiative, willingness to adopt new practices, and identification of policy windows that emerge during conflict, reform, or crisis. The fostering of relations between environmental non-government organizations and planning systems and leadership roles are also significant in catalyzing environmental transformation.  相似文献   
6.
Objective: Individuals may desire to diet or restrain from eating certain foods while attempting to quit smoking out of concern for weight gain. However, previous research and clinical tobacco treatment guidelines suggest that concurrent dieting may undermine attempts to quit smoking. The current study applied the self-control strength model, which posits that self-regulation relies on a limited strength that is consumed with use, to test whether resisting tempting sweets would lead to a greater likelihood of subsequent smoking. Design: Participants were 101 cigarette smokers randomly assigned to resist eating either from a tempting plate of sweets or from a plate of less tempting vegetables. All participants were then given a 10-min recess. Main Outcome Measures: Whether participants smoked during the break, measured with a breath carbon monoxide sample, served as the primary dependent variable. Results: As predicted, participants who resisted sweets were more likely to smoke during the break (53.2%) than those who resisted vegetables (34.0%), χ2(1, N = 101) = 3.65 p  相似文献   
7.
The unprecedented restrictions imposed due to the COVID-19 pandemic altered our daily habits and severely affected our well-being and physiology. The effect of these changes is yet to be fully understood. Here, we analysed highly detailed data on 169 participants for two to six months, before and during the second COVID-19 lockdown in Israel. We extracted 12 well-being indicators from sensory data of smartwatches and from self-reported questionnaires, filled daily using a designated mobile application. We found that, in general, lockdowns resulted in significant changes in mood, sleep duration, sport duration, social encounters, resting heart rate and number of steps. Examining subpopulations, we found that younger participants (aged 20–40 years) suffered from a greater decline in mood and number of steps than older participants (aged 60–80 years). Likewise, women suffered from a higher increase in stress and reduction in social encounters than men. Younger early chronotypes did not increase their sleep duration and exhibited the highest drop in mood. Our findings underscore that while lockdowns severely impacted our well-being and physiology in general, greater damage has been identified in certain subpopulations. Accordingly, special attention should be given to younger people, who are usually not in the focus of social support, and to women.  相似文献   
8.
ABSTRACT

The term “big data” evokes emotions ranging from excitement to exasperation in the statistics community. Looking beyond these emotions reveals several important changes that affect us as statisticians and as humans. I focus on Behavioral Big Data (BBD), or very large and rich multidimensional datasets on human behaviors, actions, and interactions, which have become available to companies, governments, and researchers. This article describes the BBD landscape and examines opportunities and critical issues that arise when applying statistical and data mining approaches to Behavioral Big Data, including the move from macro- to micro-decisioning and its implications.  相似文献   
9.
Identifying file systems metadata changes such as which files have been added, modified or removed from the file system has many usages. In this paper we present a framework we developed for identifying those changes in increasing speeds. Our framework which is composed of crawling, hashing, and scheduling components, allows to scale the crawl to multiple client workstations that operate in parallel on the same file system in a non-overlapping fashion. Experiments carried using real-world data indicate performance improvement (speedup) of up to 36X using our framework compared to legacy crawling utilities such as Linux’s ‘find’.  相似文献   
10.
Perinatal hypoxia is a major cause of infant brain damage, lifelong neurological disability, and infant mortality. N-Acetyl-Cysteine (NAC) is a powerful antioxidant that acts directly as a scavenger of free radicals. We hypothesized that maternal-antenatal and offspring-postnatal NAC can protect offspring brains from hypoxic brain damage.Sixty six newborn rats were randomized into four study groups. Group 1: Control (CON) received no hypoxic intervention. Group 2: Hypoxia (HYP)-received hypoxia protocol. Group 3: Hypoxia-NAC (HYP-NAC). received hypoxia protocol and treated with NAC following each hypoxia episode. Group 4: NAC Hypoxia (NAC-HYP) treated with NAC during pregnancy, pups subject to hypoxia protocol. Each group was evaluated for: neurological function (Righting reflex), serum proinflammatory IL-6 protein levels (ELISA), brain protein levels: NF-κB p65, neuronal nitric oxide synthase (nNOS), TNF-α, and IL-6 (Western blot) and neuronal apoptosis (histology evaluation with TUNEL stain). Hypoxia significantly increased pups brain protein levels compared to controls. NAC administration to dams or offspring demonstrated lower brain NF-κB p65, nNOS, TNF-α and IL-6 protein levels compared to hypoxia alone. Hypoxia significantly increased brain apoptosis as evidenced by higher grade of brain TUNEL reaction. NAC administration to dams or offspring significantly reduce this effect. Hypoxia induced acute sensorimotor dysfunction. NAC treatment to dams significantly attenuated hypoxia-induced acute sensorimotor dysfunction. Prophylactic NAC treatment of dams during pregnancy confers long-term protection to offspring with hypoxia associated brain injury, measured by several pathways of injury and correlated markers with pathology and behavior. This implies we may consider prophylactic NAC treatment for patients at risk for hypoxia during labor.  相似文献   
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