Preservation of multivariate stochastic orders under multivariate Poisson shock models

1997 ◽  
Vol 34 (4) ◽  
pp. 1009-1020 ◽  
Author(s):  
Tityik Wong
Keyword(s):  
Counting Process ◽  
Poisson Processes ◽  
Stochastic Orders ◽  
Shock Models ◽  
Two Systems ◽  
Multivariate Stochastic Orders ◽  
System 2 ◽  
System 1

Consider two systems, labeled system 1 and system 2, each with m components. Suppose component i in system k, k = 1, 2, is subjected to a sequence of shocks occurring randomly in time according to a non-explosive counting process {Γ i(t), t > 0}, i = 1, ···, m. Assume that Γ1, · ··, Γm are independent of Mk = (Mk,1, · ··, Mk,m), the number of shocks each component in system k can sustain without failure. Let Zk,i be the lifetime of component i in system k. We find conditions on processes Γ1, · ··, Tm such that some stochastic orders between M1 and M2 are transformed into some stochastic orders between Z1 and Z2. Most results are obtained under the assumption that Γ1, · ··, Γm are independent Poisson processes, but some generalizations are possible and can be seen from the proofs of theorems.

Preservation of multivariate stochastic orders under multivariate Poisson shock models

1997 ◽  
Vol 34 (04) ◽  
pp. 1009-1020 ◽  
Author(s):  
Tityik Wong
Keyword(s):  
Counting Process ◽  
Poisson Processes ◽  
Stochastic Orders ◽  
Shock Models ◽  
Two Systems ◽  
Multivariate Stochastic Orders ◽  
System 2 ◽  
System 1

Consider two systems, labeled system 1 and system 2, each with m components. Suppose component i in system k, k = 1, 2, is subjected to a sequence of shocks occurring randomly in time according to a non-explosive counting process {Γ i (t), t > 0}, i = 1, ···, m. Assume that Γ1, · ··, Γ m are independent of Mk = (Mk, 1, · ··, Mk,m ), the number of shocks each component in system k can sustain without failure. Let Zk,i be the lifetime of component i in system k. We find conditions on processes Γ1, · ··, Tm such that some stochastic orders between M 1 and M 2 are transformed into some stochastic orders between Z 1 and Z2. Most results are obtained under the assumption that Γ1, · ··, Γ m are independent Poisson processes, but some generalizations are possible and can be seen from the proofs of theorems.

Influence of Experience on the Thought Process of Clinical Psychologists: An Analysis from the Dual-Process Theories Framework

2020 ◽  
Vol 23 ◽  
Author(s):  
Ana M. Nieto ◽  
María R. Villarejo
Keyword(s):  
Clinical Reasoning ◽  
Clinical Psychologists ◽  
Dual Process ◽  
Process Theories ◽  
Two Systems ◽  
System 2 ◽  
Dual Process Theories ◽  
System 1 ◽  
Relationship Of ◽  
Different Levels

Abstract In the course of their work, psychologists must make judgments and complex decisions, skills that are part of clinical reasoning. Recent models approach the analysis of such process using the dual-process theories framework. This study provides an assessment of the two systems, System 1 and System 2, in forty-five clinical psychologists with different levels of experience (novices, intermediates and experts) with the purpose of exploring their level of activation and evolution throughout such stages of expertise. According to the results, clinical psychologists mainly activate System 2, M = 70.91, SD = 6.71, than System 1, M = 60.49, SD = 3.78; $ {F}_{\left(1,\kern0.5em 41\right)}=7.99;p<.01;{\upeta}^2=.163, $ when performing their clinical duties. However, no significant changes have been observed regarding the preferential use of thinking Systems 1 or 2 throughout the experience, both systems are used in a similar way in the different levels of expertise analyzed, with an increase of System 2 at the intermediate level of expertise. The results are analyzed in terms of intermediate effect and discussed focusing on the unremitting need for System 2 in psychologist work given the idiosyncratic characteristics of each case requiring treatment in the area of psychology and on the relationship of the two systems in clinical reasoning.

648 Direct Comparison of Fractional Carbon Dioxide Lasers Systems: Ablative Well Properties and Healing

2020 ◽  
Vol 41 (Supplement_1) ◽  
pp. S170-S171
Author(s):  
Heather M Powell ◽  
Molly E Baumann ◽  
Kevin L McFarland ◽  
Jennifer Zuccaro ◽  
Britani N Blackstone ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Laser System ◽  
Multiple Time ◽  
Burn Scar ◽  
Fractional Coverage ◽  
Two Systems ◽  
Laser Systems ◽  
System 2 ◽  
System 1 ◽  
Ex Vivo Study

Abstract Introduction Ablative lasers are a common tool for burn scar remodeling with numerous commercially available systems, each with varying capabilities. Among fractional CO2 (FXCO2) laser systems, the same nomenclature is utilized to describe properties of the laser including beam fluence and fractional coverage. Despite identical laser settings for these properties, the outcomes in two patient cohorts utilizing two different FXCO2 laser systems were notably different. As a result, a direct comparison of ablative wells, fractional coverage and healing between the two systems was conducted using ex-vivo and porcine models. Methods An ex-vivo study comparing fractional coverage settings (1%, 3%, and 5%) between the two different FXCO2 laser systems was first carried out (all measurements were obtained by a blinded rater using a high-powered microscope to quantify ablative area). Porcine skin was then treated with the two systems at 10–70 mJ. To compare ablative well properties, biopsies were collected and serial sectioned with the deepest/widest point of each well calculated from the histological section using ImageJ. Fractional coverage for each laser system was quantified for three different settings: 70 mJ 1%, 70 mJ 5%, and 30 mJ 5%. Finally, re-epithelialization rate (as measured by transepidermal water loss), erythema and expression of genes encoding inflammatory cytokines were quantified in a porcine burn model prior to and at multiple time points following treatment with both laser systems (70 mJ, 5% fractional coverage). Results The two laser systems produced significantly different ablative wells. In the ex-vivo study, the fractional coverage measurements obtained differed from those provided by the manufacturer by 1.6 - 8.9%. In the porcine study, at 70 mJ, the ablative wells created from system 1 were deep and narrow, on average 1251 + 183 µm deep and 142 + 32 µm wide whereas wells from system 2 were shallow and wide, 374 + 44 µm deep and 267 + 35 µm wide. Following treatment, scars treated with system 2 re-established barrier function within 7 days whereas scars treated with system 1 re-established within 4 days. A significant increase in gene expression for IL-6 was observed in both systems at 1-hour post laser. Expression levels returned to baseline in system 2 by 24 hours whereas a return to baseline was not observed until the 96-hour time point for system 2. Conclusions While different FXCO2 laser systems utilize the same nomenclature for user selected properties, the same settings are not equivalent between systems resulting in significantly different ablative wells and downstream healing. Applicability of Research to Practice Laser systems should not be considered interchangeable despite being programmed for the same settings.

scholarly journals Milk Production, Body Weight, Body Condition Score, Activity, and Rumination of Organic Dairy Cattle Grazing Two Different Pasture Systems Incorporating Cool- and Warm-Season Forages

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 264
Author(s):  
Kathryn E. Ritz ◽  
Bradley J. Heins ◽  
Roger D. Moon ◽  
Craig C. Sheaffer ◽  
Sharon L. Weyers
Keyword(s):  
Body Weight ◽  
Milk Production ◽  
Body Condition Score ◽  
Warm Season ◽  
Cool Season ◽  
Organic Dairy ◽  
Condition Score ◽  
Annual Grasses ◽  
System 2 ◽  
System 1

Organic dairy cows were used to evaluate the effect of two organic pasture production systems (temperate grass species and warm-season annual grasses and cool-season annuals compared with temperate grasses only) across two grazing seasons (May to October of 2014 and 2015) on milk production, milk components (fat, protein, milk urea nitrogen (MUN), somatic cell score (SCS)), body weight, body condition score (BCS), and activity and rumination (min/day). Cows were assigned to two pasture systems across the grazing season at an organic research dairy in Morris, Minnesota. Pasture System 1 was cool-season perennials (CSP) and Pasture System 2 was a combination of System 1 and warm-season grasses and cool-season annuals. System 1 and System 2 cows had similar milk production (14.7 and 14.8 kg d−1), fat percentage (3.92% vs. 3.80%), protein percentage (3.21% vs. 3.17%), MUN (12.5 and 11.5 mg dL−1), and SCS (4.05 and 4.07), respectively. Cows in System 1 had greater daily rumination (530 min/day) compared to cows in System 2 (470 min/day). In summary, warm-season annual grasses may be incorporated into grazing systems for pastured dairy cattle.

scholarly journals Comparison of Three Fungicide Spray Advisories for Lettuce Downy Mildew

Plant Disease ◽  
2001 ◽  
Vol 85 (8) ◽  
pp. 895-900 ◽  
Author(s):  
B. M. Wu ◽  
K. V. Subbarao ◽  
A. H. C. van Bruggen ◽  
S. T. Koike
Keyword(s):  
Downy Mildew ◽  
Drip Irrigation ◽  
Leaf Wetness ◽  
Lettuce Downy Mildew ◽  
Advisory System ◽  
System 2 ◽  
Forecasting System ◽  
Low Incidence ◽  
System 1 ◽  
First Time

Lettuce growers in coastal California have relied mainly on protective fungicide sprays to control downy mildew. Thus, timing of sprays before infection is critical for optimal results. A leaf-wetness-driven, infection-based advisory system, previously developed, did not always perform satisfactorily. In this study, the advisory system was modified by incorporating a pathogen survival component (system 1) or both survival and sporulation components (system 2). These systems were then evaluated in commercial lettuce fields in coastal California during 1996-1998. Three or four treatments were carried out in each field: (i) no spray; (ii) sprays as scheduled by the growers; (iii) sprays following modified system 1; and (iv) sprays following the original advisory system (1996) or modified system 2 (1998). Downy mildew incidence was evaluated every 2 to 9 days. In fields with drip irrigation, the number of fungicide applications was reduced by one or two regardless of the advisory system used compared to the grower's calendar-based schedule, although one unnecessary spray was recommended in 1996 at Soledad and 1997 at Salinas. Under all three systems, disease levels were low (incidence <25% and about 1 lesion per plant) for fields with drip irrigation, but not for fields with sprinklers (incidence up to 100% and 5 to 10 lesions per plant). For the first time, we established that survival and sporulation components are not needed for a lettuce downy mildew forecasting system. Instead, a threshold with a shorter period of morning leaf wetness and high temperatures were found to have potential for improving forecasting efficiency.

scholarly journals Performance of deep learning technology for evaluation of positioning quality in periapical radiography of the maxillary canine

2021 ◽  
Author(s):  
Mizuho Mori ◽  
Yoshiko Ariji ◽  
Motoki Fukuda ◽  
Tomoya Kitano ◽  
Takuma Funakoshi ◽  
...  
Keyword(s):  
Deep Learning ◽  
Characteristic Curve ◽  
Classification Performance ◽  
Learning Systems ◽  
Learning Technology ◽  
System 2 ◽  
Potential Benefits ◽  
System 1 ◽  
Periapical Radiography

Abstract Objectives The aim of the present study was to create and test an automatic system for assessing the technical quality of positioning in periapical radiography of the maxillary canines using deep learning classification and segmentation techniques. Methods We created and tested two deep learning systems using 500 periapical radiographs (250 each of good- and bad-quality images). We assigned 350, 70, and 80 images as the training, validation, and test datasets, respectively. The learning model of system 1 was created with only the classification process, whereas system 2 consisted of both the segmentation and classification models. In each model, 500 epochs of training were performed using AlexNet and U-net for classification and segmentation, respectively. The segmentation results were evaluated by the intersection over union method, with values of 0.6 or more considered as success. The classification results were compared between the two systems. Results The segmentation performance of system 2 was recall, precision, and F measure of 0.937, 0.961, and 0.949, respectively. System 2 showed better classification performance values than those obtained by system 1. The area under the receiver operating characteristic curve values differed significantly between system 1 (0.649) and system 2 (0.927). Conclusions The deep learning systems we created appeared to have potential benefits in evaluation of the technical positioning quality of periapical radiographs through the use of segmentation and classification functions.

A New Class of Oxide Superconductor (Nd, Ce, Sr)2CuO4

1989 ◽  
Vol 156 ◽  
Author(s):  
E. Takayama-Muromachi
Keyword(s):  
Crystal Structure ◽  
Crystal Chemistry ◽  
Superconducting Phase ◽  
Type Structure ◽  
Oxide Superconductor ◽  
New Class ◽  
System 2 ◽  
New Type ◽  
System 1 ◽  
Tetragonal Cell

ABSTRACTSince the discovery of the high-Tc superconductor in the La-Ba-Cu-O system [1], a great deal of experimental and theoretical effort have been made to clarify the nature of the Cu-based oxides. In order to elucidate mechanism of the high-Tc superconductivity, discovery of a new type of superconductor is no doubt of great importance. Recently, Akimitsu et al. found a new oxide superconductor in the Nd-Ce-Sr-Cu-O system [2]. Soon after their discovery, the superconducting phase was isolated and identified [3]. It has a tetragonal cell with space group P4/nmm and has a structure closely related to but different from the K2NiF4− or T'-Nd2CuO4− -type structure. Although, Tc of the Nd-Ce-Sr-Cu oxide is not so high (ca. 20 K) compared with the 1–2–3 or Bi(Tl)-based superconductors, it has aroused interest widely due to a very simple crystal structure. In this article, I will discuss superconductivity and crystal chemistry of the Nd-Ce-Sr-Cu oxide. Also, various compounds isostructural to it will be presented.

scholarly journals Three levels of naturalistic knowledge

2019 ◽  
Author(s):  
Andreas Stephens
Keyword(s):  
Semantic Memory ◽  
Conceptual Knowledge ◽  
Procedural Knowledge ◽  
Dual Process ◽  
Long Term Memory ◽  
Cognitive Ethology ◽  
System 2 ◽  
System 1 ◽  
Level Of Analysis

A recent naturalistic epistemological account suggests that there are three nested basic forms of knowledge: procedural knowledge-how, conceptual knowledge-what, and propositional knowledge-that. These three knowledge-forms are grounded in cognitive neuroscience and are mapped to procedural, semantic, and episodic long-term memory respectively. This article investigates and integrates the neuroscientifically grounded account with knowledge-accounts from cognitive ethology and cognitive psychology. It is found that procedural and semantic memory, on a neuroscientific level of analysis, matches an ethological reliabilist account. This formation also matches System 1 from dual process theory on a psychological level, whereas the addition of episodic memory, on the neuroscientific level of analysis, can account for System 2 on the psychological level. It is furthermore argued that semantic memory (conceptual knowledge-what) and the cognitive ability of categorization are linked to each other, and that they can be fruitfully modeled within a conceptual spaces framework.

scholarly journals The psychology of diagnostic error

2015 ◽  
Vol 8 (3) ◽  
pp. 91-98
Author(s):  
L. Zwaan
Keyword(s):  
Diagnostic Errors ◽  
Diagnostic Error ◽  
Dual Process ◽  
Dual Process Theory ◽  
Process Theory ◽  
Diagnostic Process ◽  
Cognitive Errors ◽  
System 2 ◽  
System 1 ◽  
Analytic Reasoning

Diagnostic errors in medicine occur frequently and the consequences for the patient can be severe. Cognitive errors as well as system related errors contribute to the occurrence of diagnostic error, but it is generally accepted that cognitive errors are the main contributor. The diagnostic reasoning process in medicine, is an understudied area of research. One reason is because of the complexity of the diagnostic process and therefore the difficulty to measure diagnostic errors and the causes of diagnostic error. In this paper, I discuss some of the complexities of the diagnostic process. I describe the dual-process theory, which defines two reasoning modes, 1. a fast, automatic and unconscious reasoning mode called system 1, and a slow and analytic reasoning mode called system 2. Furthermore, the main cognitive causes of diagnostic error are described.

Narrow and Broad Faculties in System 1 and System 2: Toward Consensus in the Debate on Modularity

2021 ◽  
Vol 21 (3-4) ◽  
pp. 261-279
Author(s):  
Norbert Francis
Keyword(s):  
Future Research ◽  
Domain Specific ◽  
Evolutionary Science ◽  
System 2 ◽  
And Performance ◽  
System 1 ◽  
Use Of Knowledge

Abstract Research on learning, the structure of attained knowledge, and the use of this competence in performance has repeatedly returned to longstanding proposals about how to better understand proficient use of knowledge and how humans acquire it. The following article takes up an exchange between Chiappe & Gardner (2011) and Barrett & Kurzban (2012) on the concept of modularity, one of these proposals. Despite the disagreements expressed, a careful reading of the contributions shows that they also left us with lines of discussion that will eventually sort out the relevant hypotheses and integrate findings for future research. These lines of work will contribute to a clearer understanding of an updated version of the modularity hypothesis that is also compatible with evolutionary science perspectives on learning. How might the categories of domain-specific and domain-general correspond to the distinction between competence and performance and to that of narrow faculty and broad faculty?

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