323,037 research outputs found
Network Saturation: Key Indicator for Profitability and Sensitivity Analyses of PRT and GRT Systems
No full textPersonal Rapid Transit (PRT) and Group Rapid Transit (GRT) are classes of fully automated public transport systems, where passengers can travel in small vehicles on an interconnected, grade-separated network of guideways, non-stop, from origin to destination. PRT and GRT are considered sustainable as they are low-emission and able to attract car drivers. The parameterized cost modeling framework developed in this paper has the advantage that profitability of different PRT/GRT systems can be rapidly verified in a transparent way and in function of a variety of relevant system parameters. This framework may contribute to a more transparent, rapid, and low-cost evaluation of PRT/GRT schemes for planning and decision-making purposes. The main innovation is the introduction of the “peak hour network saturation” S: the number of vehicles in circulation during peak hour divided by the maximum number of vehicles running at line speed with minimum time headways. It is an index that aggregates the main uncertainties in the planning process, namely the demand level relative to the supply level. Furthermore, a maximum S can be estimated for a PRT/GRT project, even without a detailed demand estimation. The profit per trip is analytically derived based on S and a series of more certain parameters, such as fares, capital and maintenance costs, daily demand curve, empty vehicle share, and physical properties of the system. To demonstrate the ability of the framework to analyze profitability in function of various parameters, we apply the methods to a single vehicle PRT, a platooned PRT, and a mixed PRT/GRT. The results show that PRT services with trip length proportional fares could be profitable already for S>0.25. The PRT capacity, profitability, and robustness to tripled infrastructure costs can be increased by vehicle platooning or GRT service during peak hours
TAMBUS: A novel authentication method through covert channels for securing industrial networks
No full textNowadays, many companies still use old and insecure protocols in Industrial Control Systems (ICSs). An example of such protocols is Modbus, one of the most employed industrial protocols. Also, companies are moving to Modbus/TCP when there are TCP devices involved in the facility. While remaining insecure, this migration also disrupts the assumption of air-gapped industrial networks, opening more attack surface to previously isolated systems. Due to legacy and efficiency constraint, the replacement of Modbus/TCP with secure protocols is not possible, generating big security issues. In this paper, we present TAMBUS (Transmitter Authentication and packet integrity in Modbus/TCP). This method is the first that at the same time: is not implemented in a secure by obscurity design and keeps the Modbus/TCP protocol compatible with legacy devices. TAMBUS allows detecting attacks with high statistical confidence, by leveraging two covert channels as a mean of providing security: 1) Storage-based, that hides authentication messages into the Modbus/TCP protocol fields; 2) Timing-based, that considers the inter-arrival time of packets. We demonstrate the feasibility and effectiveness of our method through a prototype implementation and testing in an industrial testbed environment. Our experiments confirm that TAMBUS introduces only a small overhead, negligible in most application, and it preserves the regular functioning of industrial systems. In particular, considering the storage-based covert channel, TAMBUS introduces an error into transmitted values of only 1.19×10−5%, without traffic overhead. On the other hand, TAMBUS can transmit correct security information through the timing-based covert channel with an accuracy of more than 99.99%
DOUBLE-ELECTRON EXCITATION AT THE Si K-EDGE OF AMORPHOUS SILICON
No full textIn this paper we report the experimental evidence of a double-electron excitation involving two deep core states in the X-ray absorption coefficient of a solid amorphous system. For the first time a fine structure (EXAFS) in a double-electron excitation cross section has been identified. Such feature has unambiguously allowed us to assign the dominant excitation channel to a (1s,2p) → (3p,ϵp) shake-up transition
Diffusive author(s), cohesive author: Analysis of S/N (1994)
No full textThis study indicates the ways in which various aspects of the author(s) are brought forth in Dumb type’s performance art, the S/N production. Previous research has suggested a non-hierarchical organization of Dumb type and the absence of a “privileged author” in Dumb type’s collaborative work, S/N. However, the results that I have investigated from member’s interviews on the creative process of S/N along with my analysis of the recorded images of S/N, indicate a different aspect of the author(s). First, S/N was created through, so to speak, the collective ideas of the members of Dumb type. Further, S/N has at least nine quotations from previous performances, installations, and printed writings, besides the work-in-progress technique. Explicating one of the “author functions” as given by Michel Foucault, each text has plural subjects of the author. However, it has been revealed from members’ interviews that Teiji Furuhashi had a decision-making role in selecting the members’ ideas within the performance. Since then, S/N has had plural subjects of creation; however, Furuhashi is one of the subjects of creation along with the “privileged author.” S/N has plural authors (diffusive authors) yet at the same time, it has a “privileged author,” Teiji Furuhashi (cohesive author)
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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We Can’t Compare Apples to Oranges: Establishing Validity Between Drastically Different Emotional Intelligence Tests
No full textAutism and alexithymia are two disorders characterized by deficiencies in interpersonal and emotional processing. For example, both of these disorders are associated with deficits in the ability to identify and judge the emotions of others. For diagnosis, patients are typically assessed for such deficiencies using published tests of emotion perception (e.g., the DANVA-2, the MSCEIT, the PONS) that require one to assess the emotion being displayed by a target person in a photograph or brief film clip. These tests are well known and used often, but it is rare for researchers or clinicians to ever give more than one of them to an individual. Although all three look like they are assessing the same skill, a systematic study of their agreement to show convergent validity has yet to be undertaken. The purpose of this study is to cross validate three measures of emotion perception ability. High correlations between these tests will increase the confidence researchers and clinicians will have in their validity to assess one’s skill in emotion perception and validate current diagnostic procedures for detecting disorders of interpersonal and emotional processing (e.g., autism or alexithymia).
This study had 189 undergraduate psychology students take the PONS, DANVA-2, and MSCEIT. The PONS features video clips of various facial, body and voice expressions, where participants identify the emotional context. The DANVA-2 features face and body pictures, as well as voice clips, where participants identify what emotion is expressed. The MSCEIT features face and environmental pictures for emotional quantification by participants.
As expected, all three tests of emotion processing skill correlated significantly with each other, thus providing evidence of their general validity. However, an unexpected result was observed as subscales that were most comparable in content (e.g., “reading faces for emotion”) did not show the strongest level of agreement with each other. Specifically, none of three tests subscale for perceiving emotional expressions in faces correlated significantly despite being the subtest that looked the most familiar across tests. This implies each test may be assessing different aspects of emotion processing that have not been recognized by researchers or even the test creators. Until the convergent validity for the subscales of these three tests can be established, the DANVA-2, MSCEIT, and PONS should not be considered interchangeable. They may be diagnosing aspects of emotional intelligence relevant to disorders such as autism or alexithymia, but they are not assessing the same exact thing
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We Can’t Compare Apples to Oranges: Establishing Validity Between Drastically Different Emotional Intelligence Tests
No full textAutism and Alexithymia are two disorders characterized by deficiencies in interpersonal and emotional processing. For example, both of these disorders are associated with deficits in the ability to identify and judge the emotions of others. For diagnosis, patients are typically assessed for such deficiencies using published tests of emotion perception (e.g., the DANVA-2, the MSCEIT, the PONS) that require one to assess the emotion being displayed by a target person in a photograph or brief film clip. These tests are well known and used often, but it is rare for researchers or clinicians to ever give more than one of them to an individual. Although all three look like they are assessing the same skill, a systematic study of their agreement to show convergent validity has yet to be undertaken. The purpose of this study is to cross validate three measures of emotion perception ability. High correlations between these tests will increase the confidence researchers and clinicians will have in their validity to assess one’s skill in emotion perception and validate current diagnostic procedures for detecting disorders of interpersonal and emotional processing (e.g., autism or alexithymia).
This study had 189 undergraduate psychology students take the PONS, DANVA-2, and MSCEIT. The PONS features video clips of various facial, body and voice expressions, where participants identify the emotional context. The DANVA-2 features face and body pictures, as well as voice clips, where participants identify what emotion is expressed. The MSCEIT features face and environmental pictures for emotional quantification by participants.
As expected, all three tests of emotion processing skill correlated significantly with each other, thus providing evidence of their general validity. However, an unexpected result was observed as subscales that were most comparable in content (e.g., “reading faces for emotion”) did not show the strongest level of agreement with each other. Specifically, none of three tests subscale for perceiving emotional expressions in faces correlated significantly despite being the subtest that looked the most familiar across tests. This implies each test may be assessing different aspects of emotion processing that have not been recognized by researchers or even the test creators. Until the convergent validity for the subscales of these three tests can be established, the DANVA-2, MSCEIT, and PONS should not be considered interchangeable. They may be diagnosing aspects of emotional intelligence relevant to disorders such as Autism or Alexithymia, but they are not assessing the same exact thing
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