Magnitude Estimation Approach Research Articles

Frictional Fault Strength Analysis of Palu-Koro and Matano Faults, Sulawesi, Indonesia, from Earthquake Focal Mechanism Data

ABSTRACT Sulawesi’s complex tectonic setting generates active Palu-Koro and Matano faults. Understanding earthquake mechanic is important for mitigation purpose. We performed fault strength analysis by examining its friction, through joint stress inversion and stress magnitude estimation approach, using focal mechanism data from International Seismological Centre bulletin. Friction was analyzed in four segments of the Palu-Koro Fault and two segments of the Matano Fault. Bootstrap and Jack-knife are applied to assess its uncertainty. From north to south, the friction pattern increases at the Palu-Koro Fault segments: Donggala (0.35<μs <0.56) to Palu segment (0.59<μs <0.76); then decreases sequentially: at Saluki (0.49<μs <0.55), Moa segment (0.31< μs <0.35), and further at the Matano Fault segment (Pamsoa-Ballawai) (0.26<μs <0.3). Regarding the 2018 Mw 7.5 Palu earthquake rupture, high friction at the Saluki segment coincides with and indicates its rupture termination. Seismicity records from 1977 to 2011 showed that the largest event occurred at Matano Fault has Mw less than 7.5. Low friction observed at Matano Fault correlates with small magnitude events and low fault strength.

A Magnitude Estimation Approach and Application to the Yunnan Earthquake Early Warning Network

Abstract Estimating the magnitude based on P waves is important to issue early messages to the general public for earthquake early warning (EEW) purposes. First, we reviewed part of the magnitude estimation results of the current EEW system deployed in Yunnan and found that the magnitude of the mainshock of the Yangbi earthquake sequence (Ms 6.4, as formally determined by the Yunnan Seismic Network) is severe underestimated by 0.9, whereas a number of small earthquakes are overestimated. Then, we determined the reason for this phenomenon and improved the magnitude estimation precision in Yunnan by introducing the fixed effect regression technique, adopting a flexible time window and deriving the magnitude estimation equation strictly. Finally, we examined the deficiencies of this magnitude estimation approach and demonstrated that it is possible to provide instant and reliable parameters of an earthquake through numerous inexpensive accelerometers on the ground.

Adaptation of the standardized plant analysis–risk human reliability analysis technique for the surgical setting: expert judgment approach

Objectives. Application of human reliability analysis (HRA) techniques originally developed for industrial settings to the healthcare sector may be controversial in terms of reliability and methodological level. The aim of the present study was to adapt a standardized plant analysis risk–human reliability analysis (SPAR-H) technique for application in surgical settings through suggesting more context-specific definitions for performance shaping factors (PSFs), designing precise levels and elicitation of multipliers through a domain expert judgment approach. Methods. A ratio magnitude estimation approach was used for carrying out domain expert judgment for multiplier elicitation. Experts from four teaching hospitals participated in the present study. Intra-class correlation was used in order to examine the inter-rater reliability of the estimated multipliers for each level of diagnosis and action task type. Results. Available time, threat stress, task complexity, experience/training, procedures, working conditions, human–machine interface, fatigue and teamwork were the nine suggested PSFs for the adapted SPAR-H technique. Conclusion. Context-specific definitions of the PSFs can enhance the reliability of human error probability assessments. Eventually, it could be concluded that multiplier elicitation through domain expert judgment is an efficient approach for adaptation of the HRA techniques for application in specific contexts.

Study of the Human Stickiness Perception of Wet Fabric on the Volar Forearm via Two Contact Modes: Friction and Adhesion-Separation.

Wet fabric clinging to human skin may cause stickiness perception and facilitate wearing discomfort. This study aims to investigate the stickiness perception of wet fabrics via two contact modes (friction and adhesion-separation) as well as the influences of fabric properties and contact features on stickiness perception. A set of dynamic contact devices was developed to drive the samples to move horizontally or vertically on volar forearms. According to the magnitude estimation approach, 12 subjects were asked to assess the stickiness perceptions caused by 64 types of contact stimuli. The results showed that the water absorption capacity had a significant and negative correlation with stickiness perception under the two contact modes. However, the surface roughness was neither related to stickiness perception under the friction mode nor to stickiness perception under the adhesion-separation mode. There was an interaction between contact pressure and sliding velocity. The sliding velocity at medium or high pressure had a significant effect on stickiness perception, but the separating velocity had no significant effect. Stickiness perception under the friction mode is higher than that under the adhesion-separation mode in most cases. Consequently, the friction mode was considered the main contact mode that evokes stickiness perception.

Effect of material property, surface temperature and contact duration on the thermal sensation when contacting shell materials of electronic devices

Heat generated in electronic devices is generally unevenly distributed across the casing. Contacting the hot areas may cause thermal discomfort and possibly skin burn. This study aims at better understanding the interrelationship between the thermal sensation, material properties and surface temperature for enhancing the user experience of electronic devices. A Thermal Simulation System was developed in this study to precisely control the surface temperature of shell materials to simulate various end-use conditions. Seventeen participants were asked to contact the plates with their fingers and rate their thermal sensation using the magnitude estimation approach. Results showed that thermal sensation magnitude and plate temperature followed a power function. The differences in sensation magnitude can be attributed to the thermal inertias of different materials. The findings suggested that laminated plate was generally perceived cooler when heated. Given that the surface temperature of plate is higher than skin, the thermal sensation magnitude increases with contact duration.

Magnitude Estimation Approach for Assessing Stickiness Sensation Perceived in Wet Fabrics

Sweating will trigger stickiness sensation and affecting sensorial comfort of wearer. This study aims at assessing stickiness sensation perceived in wetted fabrics utilizing the Body Movement Simulator (BMS). BMS was built to drive the samples to and fro subject’s volar forearms, providing repeatable fabric movement. Assessors were asked to compare the sample with the reference and assign numerical value to the sample using the magnitude estimation approach. 22 types of fabrics with different constructional parameters and fiber content were assessed by 23 assessors. Statistical analysis shows that within-judge reliability and between-judge consistency are satisfactory, and significant between-fabric differences are observed, demonstrating that both experimental method and assessor panel are reliable. The results reveal that thicker fabrics with higher absorption capacity and less contact area with skin contribute to weaker stickiness sensation. The perceived stickiness is highly related to water content and saturation level of samples, but poorly related to its surface friction and roughness in dry condition. This subjective assessment method is useful for assessing the stickiness sensation in textiles especially for sportswear, intimate apparel or hygiene products.

Assessing the accumulated stickiness magnitude from fabric-skin friction: effect of wetness level of various fabrics.

Increasing skin wetness tends to increase fabric–skin adhesion and friction, resulting in wear discomfort or skin injuries. Here, the magnitude estimation approach was used to assess the stickiness sensation perceived in fabrics. Seven fabric types were wetted by putting onto wet ‘skin’ surface and dried for different durations to achieve different wetness levels, simulating wearing conditions during the recovery period after sweating. Results showed that the relationship between magnitude estimates of stickiness and amount of water present in fabric demonstrated a power function. The exponents and constant from power regression show the growth rate of stickiness sensation with moisture intensity and the perceived stickiness under fixed stimulus intensity, respectively. A novel parameter, accumulated stickiness magnitude (ASM), describing how much discomfort a wetted fabric offered throughout the drying period, was developed. Thin cotton fabrics (fabric W01 and W03), having higher saturation level after contacting with wetted skin surface, arouse stronger stickiness feeling and their ASM is remarkably higher. The difference in stickiness estimates is due to the difference in chemical composition and surface geometry. This study suggests us the way to predict perceived stickiness in fabrics with different wetness levels which is useful for applications like sportswear, intimate apparel or healthcare products.

A benchmark process for measuring consumer perceptions of total quality

Researchers and business practitioners have made much progress in the last several decades towards both the measurement and management of the many aspects of quality. However, a standardised and comprehensive methodology for the measurement of consumer perceptions of total quality has remained elusive for a variety of reasons. This article proposes an illustrative pilot study that applies magnitude estimation (psychophysics) as a valid and convenient method to benchmark consumer perceptions of the various marketing dimensions that come to define total quality. The magnitude estimation approach allows specific quality-related information to be generalised and extended to other similar studies using small-size samples of targeted respondents. The ability to validate and generalise these findings across studies allows researchers and managers to observe functional relationships between existing and new marketing stimuli for related patterns and potential innovations. The observation and analysis of treatment effects over time allows management to implement a consumer-driven quality improvement programme. An empirical pilot study is presented for illustration of the methodology.

Rating the Importance of Nursing Home Residents' Quality of Life

To assess how various stakeholders involved with nursing home care rate the importance of various quality-of-life (QoL) items for hypothetical residents with varying types of impairment. A community-based exploratory description of a convenience sample. Eleven nursing homes in Florida, New Jersey, and Minnesota. Samples of registered and licensed nurses (RNs and LPNs), certified nursing assistants (CNAs), activities personnel, social workers, physicians, residents, and family members. Using a magnitude estimation approach, 17 QoL items were rated in order of importance on each of three hypothetical types of nursing home residents. Overall, there was little variation in the ratings for individual items. Ratings for persons with cognitive impairment were consistently lower. RNs'/LPNs' and CNAs' ratings were generally higher than the others, and physicians' ratings were generally lower. Residents' and families' ratings were generally lower than nurses' ratings. All stakeholders considered QoL to be important and felt that it deserves more attention in practice and regulation. A summary QoL score need not be weighted. Respondents (who were not cognitively impaired) considered QoL less important for residents with cognitive impairment. Value differences between those involved in nursing home care deserve more exploration.

An Exploration of Medical Professionals’ Perceptions of Managed Care and Policy Concepts: A Magnitude Estimation Approach

The authors begin by establishing the information content of measurement as the critical element in seeking research findings. They go on to indicate that traditional social science scaling has not provided all the information necessary to accomplish the task of measurement. They review some of the relevant literature in the field where the most common measure, Likert type scaling, has been used. They contrast that literature with research based on magnitude estimation procedures. They then apply magnitude estimation procedures to study beliefs among physicians and health care providers regarding managed care. This procedure is a novel application of magnitude estimation having never been applied in managed care research. The magnitude estimation based data are determined to yield ratio scales with true zero points, thereby, representing the highest level of measurement information. The differences between the pairs of managed care concepts using these ratio scales show that the health care concepts have greater variation in distances between them than might have heretofore been recognized because of the limitations of the scales previously applied. Consequently, the data reported have the potential to yield greater information concerning the current state of physicians’ and providers’ beliefs regarding managed care. Policy implications are discussed.

Psychophysical laws revealed by electric hearing.

Psychophysical laws relate the intensity of a physical stimulus to its perceived magnitude. G.T. Fechner hypothesized 150 years ago that the psychophysical law can be derived by measuring intensity discrimination, but modern scientists favor a direct magnitude estimation approach and are still divided on whether and how intensity discrimination is related to sensation magnitude. This controversy is partially due to the uncertainty of the role of the sensory organ in the psychophysical law. Here we bypass the auditory sensory organ with electric stimulation of the human auditory nerve and find a close coupling between intensity discrimination and loudness functions in electric hearing. Our results support Fechner's hypothesis in principle but not the exact relationship from which he derived his logarithmic law.

Developing a new metric for ADLs.

Most ADL summary measures add up the number of dependencies. They assume an equal weighting among items and require an arbitrary definition of dependency. A panel of experts in geriatrics was asked to rate a set of ADL and IADL components in terms of the contribution of each to overall dependency using a magnitude estimation (ME) technique. The ratings were done for both domains and for levels of function within each domain. The resultant scores were compared with the usual dependency count approach. The distribution of weighted items appears to have face validity. The pattern of dependency traced by the ME model was intermediate between those created by simple counts with two different definitions of dependency. The ME approach has stronger statistical properties than the ordinal scoring approach. The ME approach appears to be a reasonable and workable method for creating a measure that permits meaningful statements about the mean value of functional dependencies. This result can be used for any comparison of means, such as across individuals, across aggregates of individuals, or across time.

A Magnitude Estimation Scale for Human Values

This article describes the development and testing of a format for ratio magnitude estimation in the study of human values. This new format provides results which are free from the analytical constraints inherent in the typical ranking procedures followed in the Rokeach Value Survey. After showing that the new format produces comparable test-retest measures of stability to those obtained by Rokeach, the superior analytical possibilities offered by the magnitude-estimation approach are illustrated.

The subjective estimation of relative word frequency

Experiments reported here demonstrate the relationship between measures of relative word frequency in terms of (a) frequency counts of textual material and (b) subjective scaling procedures. With two separate subjective scaling techniques—magnitude estimation (ME) and multiple rank orders (MRO)—it was found that, with respect to the relationship of the subjective scales to direct criterion measures, the ME approach yielded scales for which the power law provided the best fit. For the MRO scales, however, a logarithmic formulation was most appropriate.