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91.
Yefim Haim Michlin Ofer Shaham 《Quality and Reliability Engineering International》2018,34(2):161-174
The Sequential Probability Ratio Test (SPRT) is widely used in the field of reliability and quality control. This paper is a continuation and a significant extension of the authors' earlier paper; it is dedicated to various risk ratios (α/β) and will lead to the increased use of the Sequential Probability Ratio Test for practical and research needs. The sample number (SN) until the test stops is a random value, and its distribution tails can be extremely long relative to the average SN (ASN). This is not suitable for practical use; therefore, truncation is required, usually by a pair of lines whose intersection, denoted as the Truncation Apex (TA), determines the maximum SN (maxSN). The optimality of the test is determined by the minimality of the SN (by means of maxSN and ASN) for a given Operating Characteristic. Presented are formulas and an algorithm for the TA and other parameters of the optimal test stopping boundaries for various α/β. This methodology also shortens the test planning process. Displacement of the TA from the optimal location results in a significant increase in ASN. The study was implemented in the Israeli standard SI‐61123. Revision of IEC 61123 and IEC 61124 (for exponential distributed data), by this study, has been accepted to the work plan of TC‐56 of IEC. The proposed methodology can be the basis for the improvement of additional standards, for example, in ISO 8422:2006. 相似文献
92.
Ofer Elior 《Centaurus; international magazine of the history of science and medicine》2020,62(1):181-197
The aim of this paper is to shed light on the transmission of Euclid's Elements in the Middle Ages, and in particular of an Arabic version of this work, which medieval sources attribute to al-Ḥajjāj ibn Yūsuf ibn Maṭar. I examine some medieval reports that explicitly ascribe certain textual variants and diagrams to this “Ḥajjāj-version.” These reports concern Books II–V and VII–X. I compare them to a medieval Hebrew version of the Elements, a single copy of which is extant in MS Paris, BnF, héb. 1011. The comparison reveals that no fewer than 14 and as many as 16 such reports conform to the Hebrew version. On the basis of these results, I argue that the circulation of a single complete version of the Elements widely recognized by medieval readers to be authored by al-Ḥajjāj, and one which perhaps was indeed his work, was not a myth. 相似文献
93.
Gil Drachuck Meni Shay Galina Bazalitsky Rinat Ofer Zaher Salman Alex Amato Christof Niedermayer Dirk Wulferding Peter Lemmens Amit Keren 《Journal of Superconductivity and Novel Magnetism》2012,25(7):2331-2335
We report the successful growth of a large (Ca x La1?x )(Ba1.75?x La0.25+x )Cu3O y (CLBLCO) single crystal. In this material, x controls the maximum of T c ( $T_{c}^{\max }$ ), with minimal structural changes. Therefore, it allows a search for correlations between material properties and $T_{c}^{\max }$ . We demonstrate that the crystals are good enough for neutron scattering and cleave well enough for Raman scattering. These results open new possibilities for cuprate research. 相似文献
94.
Yefim Haim Michlin Ofer Shaham 《Quality and Reliability Engineering International》2013,29(3):369-383
A planning methodology is proposed for the sequential probability ratio test (SPRT) for the purpose of practical application. The SPRT is the most common acceptance test in the field of reliability and quality control. In it, the hypothesis is checked that the percentage of defective items does not exceed a specified value. Truncation is resorted to compensate for the absence of a limit on the test duration, but it complicates the planning process. Moreover, the discreteness and multidimensionality of the characteristics of such tests prevent their direct comparison and optimization. To remedy these drawbacks, quality features of the test are proposed, one of which—the relative efficiency—represents the ratio of the test's weighted average sample number till its stopping and its counterpart for the nontruncated SPRT. It facilitates solution of the problems in automatic planning of the test. Another important advantage of this relative efficiency is that it yields accurate and simple formulas for the stopping boundary. Besides, these formulas permit sound choice of the truncation level already at early stages of the planning process. A planner's algorithm and an industrial example are also included. The proposed methodology can also be applied to exponential SPRT. The advantages of tests based on the proposed methodology over those in IEC‐61123 (the binomial case) and IEC‐61124 (the exponential case) are demonstrated, and revision of the standards is recommended. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
95.
Ofer Bergman Andreas Komninos Dimitrios Liarokapis James Clarke 《Personal and Ubiquitous Computing》2012,16(6):757-766
Throughout their lives, people gather contacts on their mobile phones. Some of these are unused contacts—contacts that have not been used for a long time and are less likely to be used in future calls. These contacts compete for the users’ attention and the mobile phone’s limited screen capacity. To address this problem, we developed a prototype contact list interface called DMTR, which automatically demotes unused contacts by presenting them in a smaller font at the bottom of the contact list. In phase I of this research, we asked 18 participants to assess for how long they had not used each of their mobile phone contacts. Results show that 47% of all their contacts had not been used for over 6?months or had never been used at all. In phase II, we demoted these unused contacts using DMTR and asked our participants to locate contacts that they had recently used, with and without the prototype. Results indicate that the use of DMTR reduced both the number of key strokes and the retrieval time significantly. The majority of participants indicated that it was easier for them to access their contacts using DMTR and that they would like to use it in their next mobile phone. The results provide strong evidence for the demotion principle suggested by the user-subjective approach. 相似文献
96.
Asaf Shahmoon Ofer Limon Olga Girshevitz Zeev Zalevsky 《International journal of molecular sciences》2010,11(5):2241-2252
In this paper, we present the self assembly procedure as well as experimental results of a novel method for constructing well defined arrangements of self assembly metallic nano particles into sophisticated nano structures. The self assembly concept is based on focused ion beam (FIB) technology, where metallic nano particles are self assembled due to implantation of positive gallium ions into the insulating material (e.g., silica as in silicon on insulator wafers) that acts as intermediary layer between the substrate and the negatively charge metallic nanoparticles. 相似文献
97.
Arousing and processing primary vulnerable emotions is a core change mechanism across a wide range of psychotherapies and clinical populations. This study examined the utility of 2 emotion-focused interventions—relational reframes and empty-chair enactments—in terms of arousing primary sadness associated with loss and longing among individuals suffering from unresolved anger. Twenty-nine women reporting unresolved anger underwent a single, analogue emotion-focused therapy session comprised of empathy, relational reframe, and empty-chair interventions. The arousal of sadness was measured with voice signal, voice quality, and speech fluency measures. Results indicated that both relational reframe and empty-chair interventions led to increased arousal of sadness relative to baseline nonemotional speech. Empty-chair interventions also led to increases in fear/anxiety, presumably due to the potential for rejection or attack by the significant other (i.e., attachment figure). Treatment implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
In cases of craniofacial and mandibulofacial malformations, which are mostly treated during childhood, difficult intubation conditions must generally be expected. In such cases, the laryngeal mask airway (LMA) an alternative instrument for use in endotracheal intubation is a new aid for ventilation. In certain instances, it can be used alone to induce general anaesthesia. Reports of endotracheal intubation by means of the LMA in adults have also been published. CASE REPORT: In our case, a 6-year-old boy with Pierre-Robin syndrome (triad: micrognathia, broad palatoschisis, glossoptosis) needed dental resetting. After induction of anaesthesia in this very cooperative boy with thiopentone and fluothane and relaxation with succinylcholine, it was not possible to examine the hypopharynx by laryngoscopy preparatory to nasal intubation as usual. Repeated blind attempts at nasal intubation (again with spontaneous breathing) failed, as did the attempt at fibreoptic bronchoscopic intubation, because of the narrow anatomical conditions. Finally, a laryngeal mask airway (LMA; size 2) was introduced, and as a result of this ventilation was achieved. However, endotracheal intubation was required for performance of the surgical resetting. With the fibreoptic bronchoscope, we could verify the central position of the LMA over the glottis. A tracheal tube (size 4) was inserted across the laryngeal airway without optic control. The tube connector was disconnected and a normal guide inserted into the tube to remove the LMA. The dental resetting was also performed by oral intubation. CONCLUSION: Therefore, the LMA is not only a ventilation aid, but also a valuable tool in difficult intubation conditions. In our opinion, it is necessary to provide this tool in every anaesthetic unit. 相似文献
99.
Stephen Weiner Solveig Schiegl Paul Goldberg Ofer Bar-Yosef 《Israel journal of chemistry》1995,35(2):143-154
The mineral assemblages in prehistoric sites can provide essential information on several important topics in archaeology. One of the key analytical tools used is Fourier-transform infrared spectrometry, which is operated both on-site during the excavation and in the laboratory. Three topics are reviewed here based on studies of Hayonim and Kebara caves in Israel. (1) Reaction rims form on calcitic and dolomitic rocks buried in the sediments. They are normally the result of interaction of the rock minerals with phosphate-rich groundwater. The mineralogical nature of these reaction rims can be indicative of prevailing chemical conditions in the sediments, which in turn provide information on whether or not bones are preserved at the site, or are preserved at specific locales within the site. Thus, a survey of reaction rims can be helpful in determining the potential of a future excavation site, or areas within a site, and for optimizing excavation strategies during an ongoing project. (2) The preservational states of the bones themselves, together with information on the mineralogical nature of some of the more labile sediment components, can be used for ascertaining whether or not the bone distribution patterns as excavated represent the original burial locations, or have been affected by secondary dissolution of bones in some areas and not others. (3) The ashes from wood fires are a major component of the sediments in both caves studied. Understanding and monitoring the complex series of diagenetic changes that ashes undergo in these environments can provide invaluable information, not only on the manner in which fire was used by the cave occupants, but also on a series of important processes that affect the depositional history of the site itself. The study of mineral assemblages in prehistoric cave sites, as illustrated here with 3 examples, and possibly in open-air sites as well, has the potential for contributing significantly to a better understanding of many archaeological problems. 相似文献
100.
The routine use of the chi-square tests has perhaps led to an incorrect consideration of basic underlying data in two articles in the accident and transportation fields. This paper emphasizes the necessity of comparing actual measured (observed, resultant, etc.) units with those which are expected. The two detected errors found in the literature serve as a warning stimulus in using proportions or transformed units instead of the actual numbers in chi-square tests. Several examples of data preparation are exhibited in detail. In addition, road accidents in construction or maintenance zones are analyzed as an application of correct usage of the basic available data. 相似文献