6,566 research outputs found
Native p-type transparent conductive CuI via intrinsic defects
No full textThe ability of CuI to be doped p-type via the introduction of native defects has been investigated using first-principles pseudopotential calculations based on density functional theory. The Cu vacancy has a lower formation energy than any of the other native defects, which include I vacancy (V(I)), Cu interstitial (Cu(i)), I interstitial (I(i)), Cu antisite (Cu(I)), and I antisite (I(Cu)). Combined with its shallow acceptor level, it offers sufficient hole concentrations in CuI. The natural band alignments as compared to zinc-blende ZnS, ZnSe, and ZnTe have also been calculated in order to further identify the p-type dopability of CuI. It is found that CuI has a relatively high valence band maximum and conduction band minimum, which also makes it easy to dope CuI p-type in terms of the doping limit rule. In addition, the small effective mass of the light hole-about 0.303m(0)-can provide high mobility and p-type conductivity in CuI. All of these results make CuI an ideal candidate for native p-type materials (C) 2011 American Institute of Physics. [doi:10.1063/1.3633220
Possibilities and limits of different experimental approaches of the 3D3C Photogrammetry Method for 3D analysis of the face
No full textIntroduzione: Il lavoro di ricerca sperimentale volto a definire un metodo fotografico 3D con particolari caratteristiche (precisione della misura; robustezza del metodo; rapidità di rilievo; facilità di ripresa; trasportabilità e basso peso; economicità del sistema finale; non invasività) per la rilevazione e misura senza contatto dei tessuti molli del volto, ha condotto a varie soluzioni di set-up sperimentali. Scopo della Ricerca: In questo lavoro si mettono in luce i vantaggi e gli svantaggi dei diversi set-up progettati durante la sperimentazione, confrontandoli tra loro per individuare quello che risponde meglio alle caratteristiche sopra elencate. Materiali e Metodi: Sono state progettate due tipologie diverse di approccio fotogrammetrico (con griglie proiettate e con target applicati), con cui sono sono stati scansionati sia volti reali che la testa di un manichino. Nell’ambito di ciascuna tipologia sono state sperimentate alcune varianti , modificando le condizioni di proiezione, luce, ripresa, ecc, per valutarne le differenze. Inoltre i risultati ottenuti da ciascun approccio sono stati confrontati con quelli ottenuti con la Scansione Laser (sia su volto reale che su manichino) di cui sono già note le prestazioni. Risultati: L’approccio con coded target applicati direttamente sul volto, luce ambiente, sensori fotovideo-digitali da 10 megapixel, scatti sincronizzati tra le 3 macchine, l’uso di software commerciali Photomodeler (per la ricostruzione CAD del volto) e Geomagic (per misure e confronti) si è rivelato essere quello che risponde meglio alle richieste poste alla metodica. Conclusioni: L’evoluzione della metodica a 3 macchine fotografiche ha consentito di raggiungere standard di prestazioni già molto soddisfacenti. L’ulteriore evoluzione della metodica potrebbe essere a 4 o più macchine fotografiche, in modo da ottimizzarne ulteriormente le prestazion
Reliability analysis of slopes with truncated quantile functions from small, truncated/censored samples
No full textTruncated and censored samples encountered in geotechnical engineering arise from various factors such as equipment limitations, formation characteristics, sample disturbance, unsuitable sampling methods, environmental conditions, human error, budget constraints, and geological complexities. In addition to this, unprecedented events like the COVID-19 pandemic can impede soil and rock sampling efforts, necessitating engineers and designers to work with truncated samples. The primary objective of the research is to explore novel approaches for probabilistic slope stability analysis and design under small, truncated/censored samples.
Landslides represent a prevalent and impactful geo hazard in Canada, particularly in relation to human lives and infrastructure sustainability. Thousands of landslides occur across Canada annually, resulting in direct and indirect damage estimated to range between 400 million per year. Reliability analysis, specifically utilizing the reliability index, serves as a valuable tool for evaluating engineering uncertainties, especially within the realm of slope stability. This study assesses the challenges posed by probability distribution limitations, emphasizing the relevance of truncated random variables in engineering contexts. The application of maximum entropy principles (MEPs) to estimating quantile functions (QFs) from truncated samples is discussed in the research. By employing MEPs along with partial probability weighted moments (PPWMs), the study demonstrates the effective estimation of truncated quantile functions. The optimization of these functions, determined by the Akaike information criterion (AIC), prevents the use of excessively complex models, thereby ensuring flexibility in model selection. [...
Youthhood
No full textTESTING-GROUND issue 03, Youthhood, examines worlds through youthful eyes, makes evident young ambitions, and questions how we can better empower young people to design cities, landscapes, and a planet that works for them. The issue includes contributions from: Carmel Keren, Jude Daniel Smith, Claire Edwards, Kazeem Kuteyi, Emmanuel Adarkwah, Reza Nik, Dan Cui, Kristofer Cullum-Fernandez, Fida Sassi, Simeon Shtebunaev, Daze Aghaji, Averill Dimabuyu, Sarri Elfaitouri, Rebecca McDonald-Balfour, and Ed Wall.
Rebecca McDonald-Balfour (Author), Jude Daniel Smith (Author), Daze Aghaji (Author), Carmel Keran (Author), Alexis Liu (Author), Dan Cui (Author), Kristofer Cullum-Fernandez (Author), Fida Sassi (Author), Averill Dimabuyu (Author), Ed
Impact damage of composite laminates with high-speed waterjet
No full textRain erosion may cause substantial damage to aircrafts during supersonic flight. Such event is investigated here via high-speed waterjet impact on composite laminates. An experimental setup is developed to produce waterjets with the speed up to 700m/s and a finite element model of the waterjet-composite impact event is established. The consistency of experiment and simulation results validates the adopted numerical methods. The distribution of the water-hammer pressure is non-uniform and the maximum pressure occurs near the contact periphery when the water is about to eject laterally. After a high-speed (300∼560m/s) waterjet impacts a composite laminate, the impacted surface depression is observed, and the typical surface damage presents a central region with no visible surface damage surrounded by a faded “failure ring” with resin removal, matrix cracking and minor fiber fracture. Delamination occurs at the interfaces of adjacent layers with unequal dimensions and longitudinal matrix cracking appears on the back surface. Both the velocity and the diameter of waterjets are crucial factors on CFRP damage extents. Water-hammer pressure, the stagnation pressure and propagation of stress waves are failure mechanisms for most matrix damage in CFRP impacted by waterjets.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Structural Integrity & Composite
Relationships between facial features in the perception of profile attractiveness
No full textObjective: The aim of the study was to analyse the attractiveness of modifications of lip, nose or chin positions on profile photographs. Materials and methods: A profile digital photograph was randomly selected among pictures of 50 models participating to a beauty contest and then reviewed by 10 orthodontists and 10 laypersons who unanimously rated the profile as attractive.The original picture (O) was modified so as to create protrusion and retrusion of the lips of 2,4 and 6mm, thus generating 6 new pictures (O-6, O-4, O-2, O+2, O+4, O+6). From the original picture 7 new pictures were generated: (N) with the nose protruded of 6mm and its combinations with lips protrusion and retrusion (N-6, N-4, N-2, N+2, N+4, N+6). In the same way, picture (C) was created with the chin protruded of 6mm and 6 combinations of protruded chin with protruded and retruded lips were generated (C-6, C-4, C -2, C+2, C+4, C+6). 15 orthodontists and 15 laypersons were asked to rate all the 21 pictures on Visual Analogue Scales (VAS). Results: The original picture reported the highest VAS scores. Comparing the series "C" and "N" , the pictures with Nose protrusion show higher VAS scores if compared with pictures with chin protrusion (p<.05). When nose or chin protrusion is present, the pictures that shows lip protrusion (N+2, C+2) reported higher VAS scores (p<.05). Conclusions: In cases of nose or chin protrusion, a compensatory lip protrusion improves the profile attractiveness. Nose protrusion seems to be more tolerated than a similar amount of chin protrusion. Obiettivo: Analizzare il gradimento di modifiche introdotte a livello delle labbra, del naso o del mento su fotografie del profilo. Materiali e metodi: Una fotografia di un profilo è stata scelta in maniera casuale tra le fotografie dei profili di 50 modelle che partecipavano alla fase finale di un concorso di bellezza. Tale fotografia è stata valutata da 10 ortodontisti e 10 persone comuni che hanno giudicato unanimemente il profilo come attraente. La foto originale (O) è stata poi modificata in modo da creare delle protrusioni e delle retrusioni delle labbra di 2,4 e 6mm, ottenendo così 6 nuove immagini (O-6, O-4, O-2, O+2, O+4, O+6). Partendo dalla foto originale sono state generate poi altre 7 nuove immagini: (N) con il naso ingrandito di 6mm e le combinazioni di (N) con le protrusioni e le retrusioni delle labbra (N-6, N-4, N-2, N+2, N+4, N+6). In modo analogo, la foto (C) è stata creata allungando il mento di 6mm ed ulteriori 6 combinazioni di immagini col mento allungato e labbra protruse o retruse sono state generate (C-6, C-4, C -2, C+2, C+4, C+6). 15 ortodontisti e 15 persone comuni hanno giudicato le 21 foto ottenute per mezzo di scale VAS (Visual Analogue Scales). Risultati: La foto originale ha riportato i punteggi VAS più alti. Confrontando le serie "C" e "N" , le immagini con il naso aumentato hanno mostrato punteggi VAS più alti delle immagini col mento aumentato (p<.05). Nelle serie con il naso o il mento ingranditi, le immagini che mostravano una protrusione delle labbra (N+2, C+2) hanno riportato i punteggi VAS più alti (p<.05). Conclusioni: Nei casi in cui il naso o il mento appaiono aumentati, una protrusione compensatoria delle labbra migliorerà il gradimento del profilo. A parità di aumento, un naso più grande sembra essere tollerato meglio di un mento più grande. Objectif: Le but de l'étude était d'analyser l'attraction des modifications des lèvres, de nez ou de menton sur des photographies de profil. Matèriaux et mèthodes: Une photographie numérique de profil a été aléatoirement choisie parmi des images de 50 modèles participant à un concours de beauté et alors passée en revue par 10 orthodontists et 10 laypersons qui ont unanimement évalué le profil comme attrayant. La situation originale (o) a été modifiée afin de créer la protrusion et la retrusion des lèvres de 2.4 et 6 millimètres, de ce fait produisant de 6 nouvelles images (O-6, O-4, O2, O+2, O+4, O+6). De l'image on a produit 7 originaux nouvelles images: (n) avec le nez avancé de 6 millimètres et de ses combinaisons avec la protrusion de lèvres et la retrusion (N-6, N-4, N2, N+2, N+4, N+6). De la même manière, l'image (c) a été créée avec le menton dépassé de 6 millimètres et 6 combinaisons de menton dépassé avec les lèvres en protrusion et rétraction ont été produites (C-6, C-4, C -2, C+2, C+4, C+6). 15 orthodontists et 15 laypersons ont été invités à évaluer toutes les 21 images sur des échelles d'analogue visuel (VAS). Résultats: L'image originale a rapporté les plus hauts points de VAS. Comparant la série «C» et «N», les images à la saillie de nez montrent de plus hauts points de VAS si comparé aux images avec la saillie de menton (p<.05). Quand la protrusion du nez ou du menton est présente, les images qui montre la saillie de lèvre (N+2, C+2) de plus hauts points rapportés de VAS. Conclusions: Dans les cas de la protrusion du nez ou du menton, une protrusion compensatoire des lèvre améliore l'attraction de profil. La protrusion de nez semble être plus tolérée qu'une quantité semblable de saillie de menton. Objetivo: El objetivo del estudio fue el de analizar el atractivo en las modificaciones de los labios, de la nariz o la posición de la barbilla en fotografías de perfil. Materiales y métodos: Fueron seleccionado al azar fotografías digitales de perfil; entre las fotos escogidas de 50 modelos participantes de un concurso de belleza. Luego fueron revisadas por 10 ortodoncistas y 10 personas al azar, que por unanimidad valoraron los perfiles como atractivos. La imagen original (O) se modifico con el fin de crear protrusión y retracción de los labios de 2,4 y 6mm, generando así nuevas imágenes 6 (O-6, O-4, O-2, O 2, O + 4, O +6). De la imagen original 7 nuevas imágenes fueron generadas: (N), con la nariz protraida de 6mm y sus combinaciones con los labios protraidos / retraído (N-6, N-4, N-2, N 2, N 4, N +6). De la misma manera, (figura C) se creó con el mentón sobresaliente de 6mm y 6 combinaciones de la barbilla con labios protraidos y retraídos (C-6, C-4, C -2, C +2, C + 4, C 6). 15 ortodoncistas y 15 personas calificaran las 21 imágenes en escala visual analógica (VAS). Resultados: Las imágenes originales reportaron las mayores puntuaciones de VAS. La comparación de la serie "C" y "N" , las imágenes con protrusión nariz presentan mayores puntuaciones de VAS, si se compara con las imágenes con protrusión del mentón (p<.05). Cuando se presenta la nariz o la protrusión del mentón, las imágenes que muestra la protrusión del labio (N +2, C +2) reportaron un aumento en valores del VAS (p<.05). Conclusiónes: En los casos de nariz o protrusión del mentón, la protrusión del labio compensatoria mejora el atractivo perfil. La protrusión de nariz parece ser más tolerada que una cantidad similar de protrusión del mentón. © 2010 Società Italiana di Ortodonzia SIDO
Sampling and Reconstruction of Signals on Product Graphs
No full textIn this paper, we consider the problem of subsampling and reconstruction of signals that reside on the vertices of a product graph, such as sensor network time series, genomic signals, or product ratings in a social network. Specifically, we leverage the product structure of the underlying domain and sample nodes from the graph factors. The proposed scheme is particularly useful for processing signals on large-scale product graphs. The sampling sets are designed using a low-complexity greedy algorithm and can be proven to be near-optimal. To illustrate the developed theory, numerical experiments based on real datasets are provided for sampling 3D dynamic point clouds and for active learning in recommender systems.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Signal Processing System
Ban dao ti yi zhi jie gou zai guang cui hua he guang dian cui hua zhong de yan jiu
No full textLi, Qian = 半導體异质结构在光催化和光電催化中的研究 / 李乾.Thesis Ph.D. Chinese University of Hong Kong 2015.Includes bibliographical references (leaves 145-162).Abstracts also in Chinese.Title from PDF title page (viewed on 30, December, 2016).Li, Qian = Ban dao ti yi zhi jie gou zai guang cui hua he guang dian cui hua zhong de yan jiu / Li Qian
A Conversational User Interface for Instructional Maintenance Reports
No full textMaintaining a complex system, such as a modern production line, is a knowledge-intensive task. Many firms use maintenance reports as a decision support tool. However, reports are often poor quality and tedious to compile. A Conversational User Interface (CUI) could streamline the reporting process by validating the user's input, eliciting more valuable information, and reducing the time needed. In this paper, we use a Technology Probe to explore the potential of a CUI to create instructional maintenance reports. We conducted a between-groups study (N = 24) in which participants had to replace the inner tube of a bicycle tire. One group documented the procedure using a CUI while replacing the inner tube, whereas the other group compiled a paper report afterward. The CUI was enacted by a researcher according to a set of rules. Our results indicate that using a CUI for maintenance reports saves a significant amount of time, is no more cognitively demanding than writing a report, and results in maintenance reports of higher quality. Internet of ThingsHuman-Centred Artificial Intelligenc
The Logic of Knowledge-Based Cooperation in the Social Dilemma
No full textComputer Science, Artificial IntelligenceComputer Science, Theory & MethodsCPCI-S(ISTP)
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