26 research outputs found
Achieving 100% roof-top based PV penetration in a low voltage distribution network
No full textGiven the merits of photovoltaic technology (PV), rooftop PV systems are becoming more prevalent in residential and commercial areas. As a result of the growing number of photovoltaic systems connected to low voltage (LV) distribution grids, a significant portion of power flow from photovoltaic arrays to the LV grid, As the PV penetration increases, this effect becomes more severe. This reversal of power flow (from the load side to the grid side) results in a voltage rise problem along the distribution feeder. Such an issue is more pronounced near the point of common coupling (PCC). Overvoltages are not desired as they can damage consumers’ electronic devices, burn the insulation and can trip protective equipment, causing sudden power outages. The principal objective of this study is to achieve 100% PV penetration in a low voltage distribution network while maintaining voltages within the grid constraints by employing numerous voltage control techniques. To conduct PV penetration studies, the European low-voltage distribution benchmark network developed by CIGRE is selected. PV systems of various configurations are designed and integrated into the CIGRE LV network. The results of the PV penetration analysis on the CIGRE network suggest that with the increase in the distance between the source and the load, the penetration level decreases drastically. The worst-case network model in which the penetration level is reduced to 65% is selected for employing voltage control strategies. Two main strategies have been used to improve PV penetration. In the first category of methods, the reactive power is controlled by the PV system so that voltages at the PCCs are within the grid voltage limits. Four different reactive power control methods are employed. The second category of methods are based on active power control, in which the voltages are controlled by batteries/electrolyzers by absorbing excess power generated by the PV system, avoiding reverse power flow into the grid. The results obtained reveal that all the techniques employed are successful at increasing PV penetration to 100% without violating grid voltage limits. However, it is concluded that, batteries/electrolyzer systems provide better value in terms of effectiveness in solving the voltage rise issue. They also offers lower losses, and multiple-use cases.Electrical Engineering | Sustainable Energy Technolog
Digital Image Processing for Quality Assessment of Fruits
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
Instrumented Hip Implant: A Review
No full textAbout 20% of people older than forty years old face more bone degenerative diseases. The older population is increasing quite rapidly than before which increases the need for knee or hip implants tremendously. One of the major problems of the current implants is their short lifetime and their impact on the surrounding human tissue. The short life can be attributed to implant wear, loosening, and misalignment, which often cause pain and discomfort to the patient. Functional failure of the implant may be followed by a revision surgery, which is often painful and has a relatively low success rate. Moreover, to avoid unexpected failure and unnoticed deterioration of the implant, it is important to make provision for monitoring implants' performance. Instrumented implants can provide accurate monitoring of the loosening state of the implant, which can delay the revision surgeries and its consequences. This study provides a comprehensive review of the technological development of instrumented hip implants to monitor the status of the implants. The main requirements for the implants are highlighted by reviewing different aspects of the instrumented hip implant systems. In-vivo studies reported in the literature were summarized. Vibration and Acoustic Emission (AE) measurement based loosening detection were found to be the most common methods for in-vitro studies. A comprehensive review of power supply and communication modules was presented. Despite the advancement in this field, current systems are not yet able to provide effective monitoring of the implant's status during the daily activities of patients. 2001-2012 IEEE.Manuscript received November 24, 2020; accepted December 10, 2020. Date of publication December 16, 2020; date of current version February 17, 2021. This work was supported in part by the Qatar National Research Fund under Grant NPRP11S-0102-180178 and in part by a member of the Qatar Foundation, Doha, Qatar. The associate editor coordinating the review of this article and approving it for publication was Prof. Kea-Tiong (Samuel) Tang. (Corresponding author: Muhammad E. H. Chowdhury.) Yazan Qiblawey, Muhammad E. H. Chowdhury, and Amith Khandakar are with the Department of Electrical Engineering, Qatar University, Doha, Qatar (e-mail: [email protected]; [email protected]; [email protected]).Scopu
Evaluation of mechanical properties of hybrid fiber (hemp, jute, kevlar) reinforced composites
No full textDampak Kebijakan Pelayanan Perizinan Terpadu Dan Penanaman Modal Terhadap Daya Tarik Investasi Asing Di Provinsi Riau Tahun 2013-2016
No full textWith the enactment of regional autonomy by the Indonesian government, the Riau provincial government established an institution that serves to minimize the process, the permit is always requested by the owners of capital / investors. The agency is the Integrated Licensing Service Agency and Capital Investment. This study aims to determine the policy of the institution, to know foreign investment in Riau province, to know the impact of the policy of the institution to foreign investment in Riau province. This research uses the perspectives of liberalism, this theory is pioneered by david ricardo & adam amith. The concept of this theory is based on the idea of market sovereignty in the economy. In this study the author uses the policy theory of Richard Snyder as a reference. The results of this study are positively impacting the economy in Riau province through incentive policies in the field of foreign investment including tax facilities and licensing facilities
Normal Probability and Heuristics based Path Planning and Navigation System for Mapped Roads
No full textAbstractIn a hybrid road network with multiple paths to same location having prior geographical knowledge, successful navigation for mobile robots is one of the main challenges. Path planning is one of the most important issues in the navigation process which enables the selection and identification of a suitable path for the robot to traverse in the workspace area. Path-planning for mapped roads can be considered as the process of navigating a mobile robot around a configured road map, which provides optimized path by considering roughness of roads. In this paper, we propose a novel navigation algorithm for outdoor environments, which permits robots to travel from one static node to another along a planned path. It utilizes Normal probability weight distribution (NPWD) to assign weights between two nodes dynamically. Heuristics based shortest path (HSP) algorithm is employed to solve complex optimization problems concerned with real-world scenarios. The experiments performed on categorized road databases show significant improvement in timings and complexity of system. Our results justify the effectiveness for the implementation of driver-assist system
Contact Force-Guided versus Contact Force-Blinded Cavo-Tricuspid Isthmus Ablation for Atrial Flutter: A Systematic Review and Meta-Analysis
No full textContact force (CF) is a novel approach developed to increase the safety and efficacy of catheter ablation. However, the value of CF-sensing technology for atrial flutter (AFL) cavo-tricuspid isthmus ablation (CTIA) is inconclusive. To generate a comprehensive assessment of optimal extant data on CF for AFL, we synthesized randomized controlled trials (RCTs) and observational studies from Web of Science, SCOPUS, EMBASE, PubMed, and Cochrane until 29 November 2022, using the odds ratio (OR) for dichotomous outcomes and mean difference (MD) for continuous outcomes with a corresponding 95% confidence interval (CI). Two RCTs and three observational studies with a total of 376 patients were included in our analysis. CF-guided ablation was associated with (A) a higher rate of AFL recurrence (OR: 2.26 with 95% CI [1.05, 4.87]) and total CF (MD: 2.71 with 95% CI [1.28, 4.13]); (B) no effect on total procedure duration (MD: −2.88 with 95% CI [−7.48, 1.72]), fluoroscopy duration (MD: −0.96 with 95% CI [−2.24, 0.31]), and bidirectional isthmus block (BDIB) (OR: 1.50 with 95% CI [0.72, 3.11]); and (C) decreased radiofrequency (RF) duration (MD: −1.40 with 95% CI [−2.39, −0.41]). We conclude that although CF-guided CTIA was associated with increased AFL recurrence and total CF and reduced RF duration, it did not affect total procedure duration, fluoroscopy duration, or BDIB. Thus, CF-guided CTIA may not be the optimal intervention for AFL. These findings indicate the need for (A) providers to balance the benefits and risks of CF when utilizing precision medicine to develop treatment plans for individuals with AFL and (B) clinical trials investigating CF-guided catheter ablation for AFL to provide definitive evidence of optimal CF-sensing technology
Development of Smart Squeeze Film Dampers for Small Rotors
No full textAbstractSqueeze film dampers (SFD) are lubrication elements which provide viscous damping in rotating systems. Squeeze film dampers in rotating machinery provide structural isolation, reduce the amplitudes of rotor response to unbalance and also assist to suppress rotor dynamic instability. They have been long used to subdue instability and vibration issues that are difficult to solve using conventional bearings like journal or ball bearings. Numerous studies have been tried to produce mechanically tunable dampers which allow the damping to be changed during different mode of operation. Magneto-rheological (MR) fluids are one of the strong contenders for tunable dampers. They provide the possibility to control the dynamic characteristics of conventional fluid dampers. Magneto-rheological fluids are viscous fluids suspended with micron sized ferromagnetic particles which on application of magnetic field undergo changes in their physical and mechanical properties like viscosity, stiffness, etc. This characteristic can be used to build squeeze film damper whose damping properties will change based on the input force. In present work a typical SFD is designed and development using MR fluid and tested for different amount of damping. It is observed that the damping provided by MR fluid increases with increase in magnetic field and the amplitude of vibration reduces by 70% at critical speeds
Términos de colores en el náhuatl de Cuetzalan: un enfoque etnocientífico. Dimensión Antropológica Vol. 11 Año 4 (1997) septiembre-diciembre
No full textBerlin, Brent y Paul Kay, Basic Color Terms: Their Universality and Evolution, Berkeley, EUA, University of California, Press, 1969.Beyer, Hermann, "Mitos y simbología del México antiguo", en El México Antiguo, Revista internacional de arqueología, etnología, folklore, historia antigua y lingüística mexicana, t. 10, México, Sociedad Alemana Mexicana, 1965.Boas, Franz, "Introduction to Hanbook of American Indian Languages", en J. W. Powell, (ed.), Indian Linguistic Families of American North of Mexico, University of Nrbraska Press, 1991, pp. 1-79.Burgess, D., W. Kempton y R. MacLaury, "Tarahumara Color Modifiers: Individual Variation and Evolutionary Change", en Janet Doughery (ed.), Direcction in Cognitive Anthropology, Urban y Chicago, University of Illinois Press, 1985, pp. 49-72.Campbell, Joe R., A Morphological Dictionary of Clasical Nahuatl. A Morphemes Index to The Vocabulario en lengua mexicana y castellana, fray Alonso de Molina, Madison, Hipanic Seminary of Medival Studies, 1985.Canger, Una, "Nahuatl Dialectology: A Survey an Some Suggestion", en IJAL, núm. 1, vol. 54, enero, 1988a, pp. 28-72.____________, "Subgrupos de los dialectos nahuas", en J. Kathryn Josserand y Karen Dakin (eds.), Some and Mist: Mesoamerican Studies in Memory of Thelma O. Sullivan, Osford, BAR International, Serie 402, parte II, 1988b, pp. 473-498.Cardona, Giorgio Raimondo, Los lenguajes del saber, Barcelona, Gedisa, 1990.CEPEC, Taller de tradición oral de la Sociedad Agropecuaria del CEPEC, Les oímos contar a nuestros abuelos: etnohistoria de San Miguel Tzinacapan, México, INAH, (Divulgación), 1994.Conklin, Harold, "Color Categorization", en American Anthropologist, núm. 4, vol. 75, agosto, 1973, pp. 931-942.____________, "Hanunóo Color Categories", en Journal Anthropological Research, núm. 3, vol. 42, 1986, pp. 441-446.Cuevas, Suárez Susana, "La etnociencia", en Carlos García Mora (coord.) La antropología en México. Panorama histórico, México, INAH (Biblioteca del INAH, 3), 1988, pp. 329-356.____________, "Modelos etnocientíficos", en Revista Mexicana de Estudios Antropológicos, t. 35, México, Sociedad Mexicana de Antropología, 1989, pp. 73-85.Hasler, Hangert Andrés, Hacia una tipología morfológica del náhuatl a partir del dialecto de Zacamilola, México, CIESAS (Cuadernos de la Casa Chata), 1987.____________, Manual de gramática del náhuatl moderno, México, Universidad Autónoma de Tlaxcala-CIESAS, 1995.Hill, Jane y Kenneth Hill, "A Note Utoaztecan Color Terminologies", en Anthropological Linguistic, núm. 7, vol.12, 1970, pp. 232-238.Karttunen, Frances, An Analytical Dictionary of Nahuatl, University of Texas Press, Austin, 1983.Kay, Paul y C. K. McDaniel, "The Linguistic Significance of The Meaning of Basic Color Terms", en Language, vol. 54, 1978, pp. 610-646.Kay, P., B. Berlin y W. Merrifield, "Biocultural Implications of Systems of Color Naming", en Journal of Linguistic Anthropology, núm. 1, vol. 1, junio, 1991, pp. 12-25.Kay, P., B. Berlin, L. Maffi y W. Merrifield, Color Naming Across Language, septiembre, 1994, (copia).Kenneth, Pike L., "El punto de vista ético y émico para la descripción de la conducta", en Alfred G. Amith (comp.), Comunicación y cultura, Buenos Aires, Nueva Visión, 1984, pp. 233-248.Lastra de Suárez, Yolanda, Las áreas dialectales del náhuatl moderno, México, UNAM, 1986.Launey, Michel, Introducción a la lengua y la literatura náhuatl, México, UNAM, 1992.Lounsbury, Floyd G., "Análisis estructural de los términos de parentesco", en Tzvetan Todorov (comp.), Investigaciones semánticas, Buenos Aires, Nueva Visión, 1978, pp. 81-103.____________, "El lenguaje y la cultura", en Sidney Hook (comp.), Lenguaje y filosofía, México, FCE, 1982, pp. 15-52.Lucy, John A. y Richard A. Ahwedwe, "Whorf and his Critics: Linguistic and Nonlinguistic Influences on Color Memory", en American Anthropologist, núm. 4, vol. 3, septiembre, 1979, pp. 581-615.Mackert, Michel, "The Roots of Franz Boas, Iew of Linguistic Categories as Window to Human Mind", en Historiographia Linguistica XX, núm. 2-8, 1993, pp.331-351.MacLaury E. Robert, "Color in Mesoamerica: A Theory of Composite Categorization", vol. 1, tesis doctoral, University of California, Berkeley, 1986.Maffi, Luisa, "Somali Color Terms Evolution: Gramatical and Semantic Evidence", en Anthropological Linguistic, núms., 3-4, vol. 32, 1990, pp. 316-334.Martí, Samuel, "Simbolismo de los colores, deidades, números y rumbos", en Estudios de cultura náhuatl, núm. 2, México, UNAM, 1962, pp. 93-127.Molina, fray Alonso de, Vocabulario en lengua castellana y mexicana y mexicana y castellana, México, Porrúa, 1970.Mounin, George, Historia de la lingüística: desde los orígenes al siglo XX, Madrid, Gredos, 1983.Rémi, Simeón, Diccionario de lengua náhuatl, México, Siglo XXI Editores, 1978.
Robinson, Federico (ed.), Aztec Studies, t. I y II, Summer Institute o Linguistics of the University of Oklahoma, 1969.Sahagún, fray Bernardino de, Historia general de las cosas de la Nueva España, t. 1 y 2, México, CNCA, 1989.Sapir, Edward, Selected Writing of Edward Sapir in Language, Culture and Personality, David G. Mandelbaum (ed.), Berkeley, University of California Press, 1949.Snow, David, "Samoa Color Terminologies: A Note on The Universality and Evolutionary Ordering of Color Terms", en Anthropological Linguistics, núm. 8, vol. 13, noviembre, 1971, pp. 385-390.Sullivan, Thelma, Compendio de la gramática náhuatl, México, IIH-UNAM, 1983.Troani, Duna, Estudios del mexicano de Tzinacapan, París, VER études Ibérique el latinoamericanes, 1979, (traducción del francés).Whorf, Benjamin Lee, Lenguaje, pensamiento y realidad: selección de escritos, Barcelona, Barral Editores, 1971.El objetivo de la presente investigación consiste en identificar los términos de colores que utilizan los hablantes de la lengua náhuatl de Cuetzalan y la relación que éstos tienen con su cultura. Otro propósito es descubrir los criterios que dichos hablantes emplean para ordenar y clasificar los colores que perciben
Defibrillation strategies for refractory ventricular fibrillation out‐of‐hospital cardiac arrest: A systematic review and network meta‐analysis
No full textAbstract Background and Objective Double sequential external defibrillation (DSED) and vector‐change defibrillation (VCD) have been suggested to enhance clinical outcomes for patients with ventricular fibrillation (VF) refractory of standard defibrillation (SD). Therefore, this network meta‐analysis aims to evaluate the comparative efficacy of DSED, VCD, and SD for refractory VF. Methods A systematic review and network meta‐analysis synthesizing randomized controlled trials (RCTs) and comparative observational studies retrieved from PubMed, EMBASE, WOS, SCOPUS, and Cochrane through November 15th, 2022. R software netmeta and netrank package (R version 4.2.0) and meta‐insight software were used to pool dichotomous outcomes using odds ratio (OR) presented with the corresponding confidence interval (CI). Our protocol was prospectively published in PROSPERO with ID: CRD42022378533. Results We included seven studies with a total of 1632 participants. DSED was similar to SD in survival to hospital discharge (OR: 1.14 with 95% CI [0.55, 2.83]), favorable neurological outcome (modified Rankin scale ≤2 or cerebral performance category ≤2) (OR: 1.35 with 95% CI [0.46, 3.99]), and return of spontaneous circulation (ROSC) (OR: 0.81 with 95% CI [0.43; 1.5]). In addition, VCD was similar to SD in survival to hospital discharge (OR: 1.12 with 95% CI [0.27, 4.57]), favorable neurological outcome (OR: 1.01 with 95% CI [0.18, 5.75]), and ROSC (OR: 0.88 with 95% CI [0.24; 3.15]). Conclusion Double sequential external defibrillation and VCD were not associated with enhanced outcomes in patients with refractory VF out‐of‐hospital cardiac arrest, compared to SD. However, the current evidence is still inconclusive, warranting further large‐scale RCTs
