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51.
Bond Kenneth; Ospina Maria B.; Hooton Nicola; Bialy Liza; Dryden Donna M.; Buscemi Nina; Shannahoff-Khalsa David; Dusek Jeffrey; Carlson Linda E. 《Canadian Metallurgical Quarterly》2009,1(2):129
The authors used a 5-round Delphi study with a panel of 7 experts in meditation research to achieve agreement on a set of criteria for a working definition of “meditation” for use in a comprehensive systematic review of the therapeutic use of meditation. Participants agreed that essential to a meditation practice is its use of (a) a defined technique, (b) logic relaxation, and (c) a self-induced state. Participants also agreed that a meditation practice may (d) involve a state of psychophysical relaxation somewhere in the process; (e) use a self-focus skill or anchor; (f) involve an altered state/mode of consciousness, mystic experience, enlightenment or suspension of logical thought processes; (g) be embedded in a religious/spiritual/philosophical context; or (h) involve an experience of mental silence. The results of this study provide insight into the challenges faced by researchers who want to demarcate meditative practices from nonmeditative practices, and they describe an approach to this problem that may prove useful for researchers trying to operationalize meditation in the context of comparative research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Verbal working memory involves two major components: a phonological store that holds auditory-verbal information very briefly and an articulatory rehearsal process that allows that information to be refreshed and thus held longer in short-term memory (A. Baddeley, 1996, 2000; A. Baddeley & G. Hitch, 1974). In the current study, the authors tested two groups of patients who were chosen on the basis of their relatively focal lesions in the inferior parietal (IP) cortex or inferior frontal (IF) cortex. Patients were tested on a series of tasks that have been previously shown to tap phonological storage (span, auditory rhyming, and repetition) and articulatory rehearsal (visual rhyming and a 2-back task). As predicted, IP patients were disproportionately impaired on the span, rhyming, and repetition tasks and thus demonstrated a phonological storage deficit. IF patients, however, did not show impairment on these storage tasks but did exhibit impairment on the visual rhyming task, which requires articulatory rehearsal. These findings lend further support to the working memory model and provide evidence of the roles of IP and IF cortex in separable working memory processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Angrisani L. Baccigalupi A. Schiano Lo Moriello R. 《IEEE transactions on instrumentation and measurement》2006,55(4):1077-1084
This paper deals with distance or level measurements based on ultrasonic time-of-fight estimation. Moving from a past experience concerning the proposal of a method based on discrete extended Kalman filter (DEKF) to overcome some limitations of already available ultrasonic-based techniques, a new digital signal processing method capable of granting further improvements is presented. The method is based on the unscented Kalman filter (UKF), which is a new extension of the Kalman filter theory mandated to face some DEKF problems, mainly due to its inherent linearization approach. To this aim, UKF is applied to the acquired ultrasonic signal in order to estimate the returned echo envelope as well as to locate its onset more accurately. After describing key features and implementation issues of the new method, the results obtained in a number of tests on simulated and actual ultrasonic signals, which assess its reliability and effectiveness as well as advantages with respect to the previous one, are given. 相似文献
54.
蔡妮娜 《艺术与设计.数码设计》2007,(1)
本文通过对品牌战略和文化及其二者关系的分析来说明文化的介入在企业竞争中所起到的重要作用。文化的介入使品牌战略更具包容力,使企业更具凝聚力和竞争力。只有依靠优秀的文化,企业才能像常青藤一样生机盎然、充满活力。 相似文献
55.
Frese Michael; Krauss Stefanie I.; Keith Nina; Escher Susanne; Grabarkiewicz Rafal; Luneng Siv Tonje; Heers Constanze; Unger Jens; Friedrich Christian 《Canadian Metallurgical Quarterly》2007,92(6):1481
A model of business success was developed with motivational resources (locus of control, self-efficacy, achievement motivation, and self-reported personal initiative) and cognitive resources (cognitive ability and human capital) as independent variables, business owners' elaborate and proactive planning as a mediator, and business size and growth as dependent variables. Three studies with a total of 408 African micro and small-scale business owners were conducted in South Africa, Zimbabwe, and Namibia. Structural equation analyses partially supported the hypotheses on the importance of psychological planning by the business owners. Elaborate and proactive planning was substantially related to business size and to an external evaluation of business success and was a (partial) mediator for the relationship between cognitive resources and business success. The model carries important implications for selection, training, and coaching of business owners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
The goal of this research is to study the elasto-plastic properties of La-Cr-O thin films deposited by RF-magnetron sputtering on stainless steel interconnect materials after annealing at high temperatures in air. Elastic modulus, hardness and yield pressure derived from nanoindentation data are reported for thin films in different structural states. The amorphous film has an estimated elastic modulus of 174 GPa. The moduli of annealed films are calculated to be 150, 185 and 120 GPa after annealing at 500 °C, 600 °C and 800 °C, respectively. The film annealed at 800 °C has the lowest hardness and is dramatically different from the other structural states due to formation of the nanoporosity. The amorphous film and the films annealed at 500 °C and 600 °C both have hardness of 14 GPa, which is close to the value estimated by modeling. 相似文献
57.
Quick Response (QR) codes are a type of 2D barcode that is becoming very popular, with several application possibilities. Since they can encode alphanumeric characters, a rich set of information can be made available through encoded URL addresses. In particular, QR codes could be used to aid visually impaired and blind people to access web based voice information systems and services, and autonomous robots to acquire context-relevant information. However, in order to be decoded, QR codes need to be properly framed, something that robots, visually impaired and blind people will not be able to do easily without guidance. Therefore, any application that aims assisting robots or visually impaired people must have the capability to detect QR codes and guide them to properly frame the code. A fast component-based two-stage approach for detecting QR codes in arbitrarily acquired images is proposed in this work. In the first stage, regular components present at three corners of the code are detected, and in the second stage geometrical restrictions among detected components are verified to confirm the presence of a code. Experimental results show a high detection rate, superior to 90 %, at a fast speed compatible with real-time applications. 相似文献
58.
Markus Schleburg Lars Christiansen Nina F. Thornhill Alexander Fay 《Journal of Process Control》2013,23(6):839-851
A process alarm arises when normal operation limits are exceeded and an alarm management system alerts the operator of a process plant. Due to the material, energy and information flow in a plant, single disturbances can cause multiple consequent alarm messages, and the alarm messages may overload the operator by presenting many redundant alarms. This undesired situation is called an ‘alarm flood’. In such situations, the operator might not be able to fulfil his required tasks to keep the plant within safe operation limits and to find the root cause of the disturbance. The aim of the work presented in this paper is to reduce the number of alerts presented to the operator. If alarms are related to one another, those alarms should be grouped and presented as one alarm problem. For the implementation of the concept, a software prototype has been developed to perform this reduction automatically. The analysis process starts with the alarm history which is a log containing all past alarm messages. This is combined with the plant topology of the controlled system and a set of rules. The rules describe typical interrelations between alarm messages which have a common cause. The combination of these three elements yields an effective alarm management strategy that can help plant owners and operators to comply with standards for alarm management such as ANSI/ISA 18.2 (2009) and EEMUA 191 (2007) which set limits on the number of alarms per unit time for an operator. The effectiveness of the approach is illustrated by two industrial examples where a significant reduction of alarms has been achieved. 相似文献
59.
Hand tools should be designed so that they are comfortable to use, fit the hand and are user-oriented. Six different manual, single-channel axial pipettes were evaluated for such objective outcomes as muscular activity, wrist postures and efficiency, as well as for subjective outcomes concerning self-assessed features of pipette usability and musculoskeletal strain. Ten experienced laboratory employees volunteered for the study. The results showed that light and short pipettes with better tool comfort resulted in reduced muscular activity and perceived musculoskeletal strain when they were compared with a long and heavy pipette. There were no differences in the efficiency between the different pipettes. Combining both the objective and subjective measures enabled a broader evaluation of product usability. The results of this study can be used both in product development and as information on which to base the purchase of new pipettes for laboratory work. 相似文献
60.
Dawid Polak Marcin Talar Nina Wolska Dagmara W. Wojkowska Kamil Karolczak Karol Kramkowski Tomasz A. Bonda Cezary Watala Tomasz Przygodzki 《International journal of molecular sciences》2021,22(6)
Blood platelets’ adenosine receptors (AR) are considered to be a new target for the anti-platelet therapy. This idea is based on in vitro studies which show that signaling mediated by these receptors leads to a decreased platelet response to activating stimuli. In vivo evidence for the antithrombotic activity of AR agonists published to date were limited, however, to the usage of relatively high doses given in bolus. The present study was aimed at verifying if these substances used in lower doses in combination with inhibitors of P2Y12 could serve as components of dual anti-platelet therapy. We have found that a selective A2A agonist 2-hexynyl-5’-N-ethylcarboxamidoadenosine (HE-NECA) improved the anti-thrombotic properties of either cangrelor or prasugrel in the model of ferric chloride-induced experimental thrombosis in mice. Importantly, HE-NECA was effective not only when applied in bolus as other AR agonists in the up-to-date published studies, but also when given chronically. In vitro thrombus formation under flow conditions revealed that HE-NECA enhanced the ability of P2Y12 inhibitors to decrease fibrinogen content in thrombi, possibly resulting in their lower stability. Adenosine receptor agonists possess a certain hypotensive effect and an ability to increase the blood–brain barrier permeability. Therefore, the effects of anti-thrombotic doses of HE-NECA on blood pressure and the blood–brain barrier permeability in mice were tested. HE-NECA applied in bolus caused a significant hypotension in mice, but the effect was much lower when the substance was given in doses corresponding to that obtained by chronic administration. At the same time, no significant effect of HE-NECA was observed on the blood–brain barrier. We conclude that chronic administration of the A2A agonist can be considered a potential component of a dual antithrombotic therapy. However, due to the hypotensive effect of the substances, dosage and administration must be elaborated to minimize the side-effects. The total number of animals used in the experiments was 146. 相似文献