Literatura académica sobre el tema "Directed patrol"
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Artículos de revistas sobre el tema "Directed patrol":
1
McGARRELL, EDMUND F., STEVEN CHERMAK, ALEXANDER WEISS y JEREMY WILSON. "REDUCING FIREARMS VIOLENCE THROUGH DIRECTED POLICE PATROL*". Criminology Public Policy 1, n.º 1 (noviembre de 2001): 119–48. http://dx.doi.org/10.1111/j.1745-9133.2001.tb00079.x.
2
Bonkiewicz, Luke. "Shooting Stars". Police Quarterly 20, n.º 2 (5 de octubre de 2016): 164–88. http://dx.doi.org/10.1177/1098611116671309.
Resumen
This study analyzes two decades of data from a municipal police agency and describes the average patrol officer career productivity trajectory. We find that declines in productivity begin immediately after the first year of service and worsen over the course of officers’ careers. After their 20th year, patrol officers generate 88% fewer directed patrols, 50% fewer traffic warnings, 58% fewer traffic citations, 41% fewer warrant arrests, and 57% fewer misdemeanor arrests compared to officers with 1 year of experience. Using a patrol officer productivity metric called Z-score per Productive Time ( Z-PRO), we estimate that each additional year of service decreases an officer’s overall productivity by about 2%. Z-PRO also indicates that after 21 years of service, an average officer will be approximately 35% less productive overall than an officer with 1 year of service.
3
Harinam, Vincent y Lawrence W. Sherman. "Targeting Knife-Enabled Homicides for Preventive Policing: A Stratified Resource Allocation Model". Cambridge Journal of Evidence-Based Policing 4, n.º 3-4 (19 de agosto de 2020): 125–33. http://dx.doi.org/10.1007/s41887-020-00049-w.
Resumen
Abstract Research Question How can police translate differing risk levels for knife homicide into a resource allocation model that follows the evidence? Data The data for this publication are taken from the open access tables published in this journal by Massey et al. Cambridge Journal of Evidence-Based Policing, 3:1-20, (2019). Those data show the linear relationship between the number of non-fatal knife assaults in a lower super output area (LSOA) in 1 year and the risk of a knife-enable homicide in the subsequent year, as well as how many of the 4835 LSOAs fell into each of five levels of increasing homicide risk. Methods The data from Massey’s research are re-calculated to show how a hypothetical number of 15-min police patrols could be allocated across all areas on the basis of a combination of knife-enabled (KE) homicide risk level and the volume of LSOAs at each of the five levels of knife homicide risk. We display these results using both tables and multi-layered “wedding cake” images to show the size of different dimensions of each level, including proportion of total homicides and directed patrol frequency per LSOA at each of the five risk levels. Findings Based on the hypothetical allocation of 10,000 patrol visits of 15 min in length, the highest risk group, with a forecasted 6% of all KE homicides, would receive 600 police patrols, divided by the 41 LSOAs at that risk level = 15 patrols across every 10 days. At the lowest level of risk, the 2787 LSOAs would share the 3000 patrols that a group of LSOAs would recieve for having 30% of homicides, which equals 1.1 patrols every 10 days. The hypothetical premise is that every LSOA gets some patrol, but the highest risk areas get 15 times more patrol to follow the evidence of risk. The formula is to (1) allocate resources by proportion of homicide at each risk level; (2) divide the allocated resources by the number of areas in each risk level group; and (3) allocate the resulting resources per day to each area in each of the 5 levels. Conclusion Police face difficult tradeoffs between targeting more policing to fewer areas of higher risk (with more efficiency) or to more areas of lower risk (with more effectiveness). The use of a formula combining risk and volume can help guide such decisions, illustrated by a layered “wedding cake” visualization for gaining clarity and legitimacy in communications.
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Boba Santos, Rachel y Bruce Taylor. "The integration of crime analysis into police patrol work". Policing: An International Journal of Police Strategies & Management 37, n.º 3 (12 de agosto de 2014): 501–20. http://dx.doi.org/10.1108/pijpsm-08-2012-0075.
Resumen
Purpose – The purpose of this paper is to examine national survey data of police agencies in the USA to explore the current state of crime analysis integration to patrol crime reduction work. Design/methodology/approach – The data examined in this paper are from a national quantitative survey which sought to understand how crime analysis results are used by officers as well as higher ranking personnel in the patrol division and what types of strategies are implemented using crime analysis. Findings – The findings show that the routine use of crime analysis is not well integrated. Despite the low integration, however, some differences were found. Management uses crime analysis the most overall, but officers and first-line supervisors use tactical crime analysis more routinely than management, where management personnel use evaluation most routinely. Tactical crime analysis is used most often for directed patrol, strategic for both directed patrol and general information, and evaluation for both general information and crime prevention. Analysis of using analysis proactively shows that agencies use tactical crime analysis most proactively, followed by the strategic crime analysis, then evaluation. Research limitations/implications – The study relies on self-report surveys, so the results may suffer from some of the general limitations of self-reports. Also, the study resulted in a lower response rate than surveys of police agencies typically achieve. Although responding and non-responding agencies were comparable in terms of population size, number of officers, and region of the country, the response rate was about 55 percent. However, it is a possibility based on the analysis results that non-responses may reflect a disinterest in the topic or the lack of integration of crime analysis. Originality/value – This is the first national survey that focussed specifically on crime analysis integration in patrol work for crime reduction. The value of the results presented here are in the description of the current state of crime analysis integration in the USA which has not been investigated in such depth before and the identifications of gaps in both research in practice.
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Piza, Eric L., Joel M. Caplan, Leslie W. Kennedy y Andrew M. Gilchrist. "The effects of merging proactive CCTV monitoring with directed police patrol: a randomized controlled trial". Journal of Experimental Criminology 11, n.º 1 (15 de julio de 2014): 43–69. http://dx.doi.org/10.1007/s11292-014-9211-x.
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Frogner, Louise, Henrik Andershed, Odd Lindberg y Marcus Johansson. "Directed Patrol for Preventing City Centre Street Violence in Sweden — A Hot Spot Policing Intervention". European Journal on Criminal Policy and Research 19, n.º 4 (14 de febrero de 2013): 333–50. http://dx.doi.org/10.1007/s10610-013-9197-3.
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Baloch, Wajeeh, Bhawani Shanker y Sumbul Ghulamani. "Controlling Self-Directed Vehicle via Webpage using Raspberry Pi Lighttpd Webserver". Sir Syed University Research Journal of Engineering & Technology 6, n.º 1 (19 de diciembre de 2016): 4. http://dx.doi.org/10.33317/ssurj.v6i1.43.
Resumen
Internet of Things (IoT) and Tele-Robotics aremost advanced technologies that provide a vision where anyobject in this world can be connected to anything else. Thesetechnologies enable us to build communication among variousentities such as Wireless Sensor Networks (WSN) devices, homeappliances, medical equipment, RFIDs etc. An intelligent Self-Directed Vehicle (SDV) incorporated with features of Internet ofThings (IoT) is presented in this work. In order to manuallycontrol the SDV, a web page (embedded with google maps) isdeveloped and uploaded on Lighttpd server on Raspberry Pi.Lighttpd server can act like a normal apache server. User cannavigate SDV manually using maneuvering control buttons. Theonboard camera provides visual awareness. This technology canbe utilized and implemented in a number of areas such asmilitary, where SDV can undertake missions like dronesurveillance, border patrol etc. Furthermore, our work highlightsthe use of webservers for interconnecting devices and describesthe use of internet to control SDV from a remote end withRaspberry Pi Lighttpd Web Server.
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Piza, Eric L., Andrew M. Gilchrist, Joel M. Caplan, Leslie W. Kennedy y Brian A. O’Hara. "The financial implications of merging proactive CCTV monitoring and directed police patrol: a cost–benefit analysis". Journal of Experimental Criminology 12, n.º 3 (23 de junio de 2016): 403–29. http://dx.doi.org/10.1007/s11292-016-9267-x.
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Tie, Chun Hua y Yan Chun Shen. "An Improved Graph-Based Depth-First Algorithm and Dijkstra Algorithm Program of Police Patrol". Advanced Materials Research 433-440 (enero de 2012): 4135–41. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.4135.
Resumen
The urban road network is abstracted as a directed graph in this paper，according to the theory of graph theory. It uses depth-first traversal algorithm of graph，and combining with Dijkstra shortest path algorithm，futhermore ,these two algorithms are improved，so that , the model of this regional division are built which on city roads for patrol’s police Alarm practical speed and distance as the verification conditions，we propose an efficient program for the city police patrol.
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Chang, Kang-Ming, Hao-Chen Xu, Congo Tak-Shing Ching y Shing-Hong Liu. "Wireless Patrol Sign-In System with Mental Fatigue Detection". Journal of Healthcare Engineering 2018 (12 de noviembre de 2018): 1–6. http://dx.doi.org/10.1155/2018/6419064.
Resumen
Current sign-in methods of patrolling security guards mainly comprise signature, image identification, and fingerprint identification; notably, none of these methods indicate the physical and mental conditions of such guards. In particular, when patrolling security guards perform their duties consecutively for a long period of time, adequate attention should be directed toward their levels of mental fatigue. When a handwriting sign-in system is adopted, security guards may not record their sign-in time accurately, or they may fake signatures during long shifts. In addition, image identification systems cannot comprehensively reflect the physical and mental statuses of on-duty security guards, particularly their levels of fatigue. Monitor fatigue in patrolling security guards is important to avoid burnout and stress in the workplace. Therefore, in this study, a patrolling sign-in system that integrates physiological signals and images was designed. A thermometer, hand dynamometer, and electromyography sensor were combined to measure physiological signals. Results showed that hand grip strength and the median frequency of electromyography signals gradually reduced when muscle fatigue occurred. The system determined whether a security guard had signed in punctually and whether this person should stay on duty. Overall, this system was verified to operate effectively, and it is therefore applicable for monitoring the sign-in of patrolling security guards who work long shifts. This case series study proposed a conceptual prototype of the system; large-scale testing should be performed in subsequent research.
Tesis sobre el tema "Directed patrol":
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Johnsson, Caroline y Kriv Ado. "Ordningsvakter på Möllevångstorget : En studie om ordningsvakter som förebyggande åtgärd". Thesis, Malmö universitet, Fakulteten för hälsa och samhälle (HS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-42539.
Resumen
Studien har ett tvådelat syfte. Först ämnar studien undersöka utifrån vilka förutsättningar det tagits beslut om att implementera kommunala ordningsvakter att patrullera på och kring Möllevångstorget i Malmö, vidare att undersöka vilka mål och förväntningar involverade aktörer har på insatsen. Syftet är också att undersöka upplevelsen av ordningsstörningar och trygghet och slutligen uppfattning om ordningsvakter bland personer som besöker Möllevångstorget. För att uppnå studiens första syfte genomfördes semistrukturerade intervjuer med nyckelinformanter, urvalet bestod av sju personer. För att uppnå det andra syftet genomfördes i första hand strukturerade intervjuer med personer som vistades på platsen, i andra hand erbjöds de en webbenkät. 42 personer deltog på en strukturerad intervju och 18 personer besvarade webbenkäten. Det framkom genom de semistrukturerade intervjuerna att narkotikaförsäljning och otrygghet är ett stort problem i området. Målet är framför allt att tryggheten ska öka i samband med LOV§3-insatsen. Det önskades också att det finns en väl fungerande samverkan mellan aktörer som kan bidra till att brottsligheten och otryggheten minskar, att inte enbart förlita sig på att ordningsvakter löser alla problem. Resultatet från de strukturerade intervjuerna/webbenkäten visar att klotter och öppen drogförsäljning är de ordningsstörningar som upplevs förekomma mest frekvent. Tryggheten på platsen förefaller vara relativt hög med viss variation vad gäller tidpunkt, då oro att utsättas för brott är högre under kvällstid. Slutligen visar studien att förtroende kan vara av betydelse för hur effektiva ordningsvakter uppfattas vara.The study has a twofold purpose, the first is to investigate the conditions on which decisions have been made to implement municipal security guards to patrol around and on Möllevångstorget in Malmö. Furthermore, the study aims to investigate goals and expectations the involved actors have on the current operation. The purpose of the study is also to investigate the experience of disorder and fear of crime and lastly the perception regarding security guards, among people who visits Möllevångstorget. To achieve the first purpose of the study, semi-structured interviews were conducted with key informants, the sample consisted of seven people. To achieve the second purpose of the study, primarily structured interviews were conducted and secondly a web survey was offered. 42 people participated in a structured interview and 18 people answered the web survey. What emerged from the semi-structured interviews indicates that drug sales and fear of crime is a common issue in the area. Furthermore, the main goal is for the security to increase in connection with the LOV§3 operation. It was also desired that there is a well-functioning collaboration between actors that can contribute to reducing crime and fear of crime, and not to rely solely on security guards solving all problems. The results from the structured interviews/ web survey indicate that graffiti and open drug sales are disorders that are perceived to occur most frequently. The fear of crime in the area appears to be relatively low with certain variations in terms of time, as fear about being exposed to crime is higher in the evening. Finally, the study shows that trust can be important for how effective security guards are perceived to be.
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Muñoz, Martel Karin Soledad. "Análisis jurisprudencial en materia de cuidado personal y relación directa y regular". Tesis, Universidad de Chile, 2011. http://www.repositorio.uchile.cl/handle/2250/111568.
Resumen
Memoria (licenciado en ciencias jurídicas y sociales)La presente memoria tiene por objetivo analizar la jurisprudencia nacional que verse sobre las materias de cuidado personal y relación directa y regular, con la finalidad de examinar y determinar cuáles son los criterios de atribución que consideran los jueces a la hora de entregar a uno u otro progenitor el cuidado personal de los hijos, cuáles son los criterios de determinación del régimen de relación directa y regular, cuáles son las problemáticas que a la hora de resolver estos conflictos enfrentan los jueces, analizar la participación de los diferentes individuos afectados por la crisis familiar, entre otros objetivos, todo ello bajo el prisma de los principios del derecho de familia e infancia. A partir de esa investigación, comprobar si la aplicación de la normativa vigente se condice con la realidad imperante y permite que, en la práctica, las crisis familiares sean resueltas por los jueces de la manera más adecuada a las necesidades de cada familia. Para lograr tal cometido se realizó un análisis de sentencias emanadas de toda la jerarquía de tribunales de nuestro país, con el objeto de obtener una visión generalizada de los razonamientos jurídicos utilizado por nuestros jueces, concluyendo, a partir de la muestra analizada, que es necesario realizar reformas legislativas respecto a las materias de cuidado personal y relación directa y regular, y modificaciones en la aplicación de la normativa vigente y los principios generales del derecho de familia por parte de los jueces, para que las resoluciones de los conflictos de familia se adecuen a la realidad social imperante en nuestro país y, especialmente, sean las más acertadas a las necesidades de cada familia.
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Oyarce, Bustamante Carolina. "El derecho y deber a mantener una relación directa y regular con los hijos: de su configuración en la legislación chilena y su eficacia según jurisprudencia". Tesis, Universidad de Chile, 2005. http://www.repositorio.uchile.cl/handle/2250/107595.
Resumen
Memoria (licenciado en ciencias jurídicas y sociales)Sin perjuicio del debido análisis dogmático, el principal aporte de esta investigación se traduce en intentar visualizar la forma que el máximo Tribunal Jerárquico de nuestro país ha recogido las diversas modificaciones existentes en la materia y observar cómo la jurisprudencia a llevado a la práctica los principios inspiradores de tales reformas. En dicho espíritu, comprende un análisis acucioso análisis jurisprudencial principalmente de sentencias pronunciadas por la Corte Suprema, buscando revelar la existencia de fallos suficientes como para constituir ciertas tendencias en uno sentido u otro, determinar si hay pronunciamiento de fondo o solamente se resuelve acorde a criterios formales; y, al mismo tiempo, establecer los tópicos y vías recurrentes por los cuales llega a conocimiento del máximo tribunal del país, tales como la acusación de abuso sexual cada vez mas invocada en sede jurisdiccional; el interés superior del niño como uno de los íconos de la legislación en materia de familia y en especial, el derecho del menor a ser oído en audiencia respecto de asuntos que vayan a afectar su vida, como una de sus manifestaciones, de su valor probatorio; y la vinculación en general de todos los conflictos de índole familiar cuando existen quiebres o rupturas en la pareja; sin perjuicio de recurrir a resoluciones de Juzgados de Menores, tribunales encargados de zanjar la problemática familiar en primera instancia, vislumbrar la manera en que el aparato judicial absorbe y asume esta clase de dificultades, con el objeto de llegar a dilucidar desde la perspectiva práctica, la eficacia de las reformas (Código Civil y Ley de Menores), señalar la existencia de discrepancias entre la norma de jerarquía legal y su aplicación, y comparar la realidad con la norma, desde el punto de vista de los objetivos y ventajas, que pretendían traer consigo tales reformas, que finalmente, es la posibilidad de comunicación entre los progenitores con el menor, en la forma que más se asemeje, a la relación que hubiese habido de no existir el quiebre o separación entre los padres
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Liou, Sheng-huei y 劉勝輝. "Study on the Satisfaction of Director and Deputy Director of Eastern Coast Patrol Office Regarding the Performance Evaluation of Logistic Support". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/dx7696.
Resumen
碩士國立臺東大學
區域政策與發展研究所
96
To follow the trend of the world and effectively manage the water territory so as to strive for our maritime benifits and rights, “Coast Guard Administration of Executive Yuan” (hereafter referred to as “Coast Guard Administration”) was establishes on January 28th, 2001. Based on the Coast Guard Act, its authority would be to implement the crime investigation and the smuggling investigation on the sea and at non-trading ports, check the illegal entry and exit of the border of our country, control and maintain the maritime traffic and order, and perform the rescue of marine disaster and other serving work. Besides, performing the protection of marine environment, the maintenance of marine resources as well as fishery protection and safeguard based on domestic legal provision is most difficult and complicated. Furthermore, in order to perform the tasks mentioned above, we would need all kinds of equipments which are very sophisticated and detailed, as these facilities, from the purchase, obtainment, and distribution to the subsequent maintenance, elimination, the changes of records, other logistic support, and the management, would take tremendous manpower, resources, and expense. Therefore, how the management efficiency and the effect on the logistic support of coast patrol can be enhanced to meet the requests for coast guard personnel’s duty-implementation and life so that the operation of coast guards’ missions can be assured has become an issue worth more in-depth research and discussion. This study is conducted primarily in use of the questionnaire and quantified analysis, while its main scope of research would be limited to the allocation of their clothing, regular gears, vehicle maintenance, repairing work, and others items for the coast guard units and personnel. The study would survey the satisfaction of director and deputy director of Eastern Coast Patrol Office regarding the performance evaluation of logistic support, generalize and analyze the problems connected with the current logistic support system, and formulate future improvement strategy for logistic support so as to establish comprehensive logistic support system, formulate and simplify the standard operation procedures. Through that, each management plan for logistic support could be carried out more effectively and their economic effects will turn to be great. The research shows that the satisfaction of director and deputy director for Eastern Coast Patrol Office regarding the performance of logistic support has gone up to 82.5%. Among them, the “customer aspect” of hierarchical performance is considered the best. Meanwhile, the rate of satisfaction with logistic support goes to 79.1%. Among them, the satisfaction of “maintenance control” hierarchy is found to be the highest. Thus, we can tell that the administration of logistic support can fully satisfy each unit when processing and managing the equipment maintenance and repair for each unit in Eastern Coast Patrol Office. Besides, extremely high praise is awarded to the logistic support management system for its brilliant service performance by every unit.
Libros sobre el tema "Directed patrol":
1
Crowe, Timothy D. Directed patrol manual: Juvenile problems. Washington, D.C: U.S. Dept. of Justice, Office of Juvenile Justice and Delinquency Prevention, 1985.
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McGarrell, Edmund F. Targeting firearms violence through directed police patrol. Indianapolis: Hudson Institute, 1999.
3
Ekstrand, Laurie E. Border control: Revised strategy is showing some positive results : statement of Laurie E. Ekstrand, Associate Director, Administration of Justice Issues, General Government Division, before the Subcommittee on Immigration and Claims, Committee on the Judiciary, House of Representatives. Washington, D.C: The Office, 1995.
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1956-, McGarrell Edmund F., Chermak Steven M, Weiss Alexander y National Institute of Justice (U.S.), eds. Reducing gun violence: Evaluation of the Indianapolis Police Department's directed patrol project. Washington, DC: U.S. Dept. of Justice, Office of Justice Programs, National Institute of Justice, 2002.
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United States. General Accounting Office., ed. Border Patrol: Southwest border enforcement affected by mission expansion and budget : statement of Harold A. Valentine, Associate Director, Administration of Justice Issues, before the Subcommittee on International Law, Immigration and Refugees, Committee of the Judiciary, House of Representatives. [Washington, D.C.]: The Office, 1992.
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Carasso, Odette y Pierre Albert. Arthur Meyer, Directeur du Gaulois : Un patron de presse juif, royaliste et antidreyfusard. Imago, 2003.
7
Royan, Nicola. The Noble Identity of Gavin Douglas. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198787525.003.0009.
Resumen
This essay takes up Sally Mapstone’s contention that Scottish Advice to Princes was directed as much to magnates and their supporters as it ever was to the king, and applies it to Gavin Douglas’ Eneados. It considers the manner in which Douglas’ translation represents nobility, national identity, and political violence, with reference to Douglas’ own magnatial identity and that of the poem’s patron, William Sinclair. It considers both the prologues and the translated texts, examining further the relationship between them. In so doing, it places the Eneados in the context of Virgilian criticism as well as Older Scots poetic traditions, and demonstrates parallels in language choices regarding war, government, and rule.
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Forrestal, Alison. Early Patrons and Favours. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198785767.003.0003.
Resumen
Chapter 2 provides a narrative account of Vincent de Paul’s activities between 1612 and 1617. It concentrates on new connections with prominent dévots in Paris, whose sponsorship provided him with opportunities for material stability and for the expansion of his rather limited pastoral experience. These included his patron employers, the high noble Gondi family, and Pierre de Bérulle, founder of the French Oratory, and founding figure of the French School of Spirituality. The appointments that resulted from these contacts were a preceptorship in the Gondi household, followed by a role as spiritual director to Madame de Gondi, and two sojourns as curé of the parishes of Clichy and Châtillon-lès-Dombes.
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Parsons, Laurel y Brenda Ravenscroft. Hildegard of Bingen, O Ierusalem aurea civitas (ca. 1150–1170). Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190237028.003.0002.
Resumen
This chapter contextualizes Hildegard of Bingen’s monumental sequence for her monastic community’s patron St. Rupert, O Ierusalem aurea civitas, both within Hildegard’s own output of sequences, and within the sequence repertory at large. Considering her deep sensitivity to the relationship between text and music, including close attention to grammatical structure, word stress, and word and syllable parsing, the essay proposes that Hildegard uses a varied repetition technique, adapting the standard sequence form. Instead of strict repetition, she varies many elements of the melodic surface through expansion or contraction, preserving an audible sense of repetition while responding directly to new text structures. The essay provides a textual and musical analysis of the entire sequence, demonstrating the composer’s large-scale control of musical structure.
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United States. General Accounting Office., ed. Border management: Dual management structure at entry ports should end : statement of J. William Gadsby, Director, Government Business Operations Issues, General Government Division, before the Subcommittee on Information, Justice, Transportation, and Agriculture, Committee on Government Operations, House of Representatives. [Washington, D.C.]: The Office, 1993.
Capítulos de libros sobre el tema "Directed patrol":
1
Schultz, Gerrit. "Direct Reconstruction for Cartesian PatLoc Imaging". En Magnetic Resonance Imaging with Nonlinear Gradient Fields, 155–206. Wiesbaden: Springer Fachmedien Wiesbaden, 2013. http://dx.doi.org/10.1007/978-3-658-01134-5_5.
2
Schultz, Gerrit. "Direct Reconstruction for Radial PatLoc Imaging". En Magnetic Resonance Imaging with Nonlinear Gradient Fields, 207–33. Wiesbaden: Springer Fachmedien Wiesbaden, 2013. http://dx.doi.org/10.1007/978-3-658-01134-5_6.
3
Brayne, Sarah. "Directed Surveillance". En Predict and Surveil, 56–73. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190684099.003.0004.
Resumen
This chapter focuses on directed surveillance, or the surveillance of people and places deemed suspicious. Big data is associated with a shift from reactive to predictive policing. Predictive policing refers to analytic techniques used by law enforcement to forecast potential criminal activity. It involves using data to determine current crime patterns and direct patrol resources, such as where officers should go and who they should stop. In general terms, the stages of predictive policing are collection, analysis, intervention, and response. The chapter analyzes how the Los Angeles Police Department (LAPD) conducts person- and place-based predictive policing; why it adopted different forms of predictive policing; how it uses algorithms to quantify criminal risk; how the police do—and do not—incorporate insights from the algorithms into their work in the field; and how predictive policing serves as a foundation for ongoing intelligence gathering.
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Fisher, Daniel. "Spun Dry: Mobility and Jurisdiction in Northern Australia". En Looking for Law in All the Wrong Places, 62–84. Fordham University Press, 2019. http://dx.doi.org/10.5422/fordham/9780823283712.003.0004.
Resumen
This chapter pursues an ethnographic account of intra-indigenous relations and jurisdictional contest in urban northern Australia. Its narrative explores the relationship between Aboriginal community policing and emergent forms and figures of urban mobility and morbidity in Darwin, capital of Australia's Northern Territory. While Darwin's indigenous patrols have no police powers and its officers disavow any authority as police, they do have a certain status vested in them by the traditional owners of the country on which they patrol. Their Aboriginal-directed efforts thus entail both an assertion of indigenous jurisdiction and an accompanying reflexivity about the substance and limits of its reach-limits informed by settler colonial oversight, by the diversity of indigenous claims to urban space, and by poetic figures and mediatized narratives that trope the volatility of Aboriginal dispersal and displacement. The chapter explores the ways patrols negotiate their authority and reckon its limits, extending a local poetics of jurisdiction and movement to illuminate the new urban worlds they traverse.
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"The Director". En Making Patton, 60–72. University Press of Kansas, 2020. http://dx.doi.org/10.2307/j.ctvzsmd5v.9.
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Van De Mieroop, Dorien. "Een verkenning van de pragmatische functies van directe rede in narratieven". En Patroon en argument, 683–96. Leuven University Press, 2014. http://dx.doi.org/10.2307/j.ctt14jxsr0.49.
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Macías-Rojas, Patrisia. "Victims and Culprits". En From Deportation to Prison. NYU Press, 2016. http://dx.doi.org/10.18574/nyu/9781479804665.003.0005.
Resumen
The criminal alien mandate requires that border agents direct enforcement resources toward high-priority targets, principally those with a criminal record. Rather than processing apprehended undocumented migrants according to explicit “racial” and “national” criteria, agents now distinguish between victims and criminals. Focusing on Border Patrol–migrant interactions, this chapter examines how enforcement priorities rooted in the Criminal Alien Program have transformed apprehension and deportation practices on the border.
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Kemeny, P. C. "The Travails of Becoming a University, 1888-1902". En Princeton in the Nation's Service. Oxford University Press, 1998. http://dx.doi.org/10.1093/oso/9780195120714.003.0007.
Resumen
In bringing the College of New Jersey to the brink of university status, McCosh stood on the verge of the promised land. As the nineteenth century was coming to a close, alumni, professors, and trustees in Princeton, like those at many other American colleges and universities, were eager to see the institution position itself so that it would be better able to meet society’s need for moral and thoughtful leaders, practical knowledge, and scientific expertise once the nation entered the twentieth century. With the future direction of the institution hanging in the balance, the choice of who should succeed McCosh divided the college community along the same lines as had emerged earlier over both the alumni’s attempt to secure direct representation on the Board of Trustees and McCosh’s failed attempt to make the college a university. Whereas McCosh harmoniously upheld the college’s dual mission through the breadth of his scholarly interests, the warmth of his evangelical piety, and the force of his personality, the two candidates who vied for the presidency after his resignation possessed only a portion of McCosh’s qualities and appealed to only one part of the Princeton community. Francis L. Patton appealed to those primarily, though not exclusively, interested in preserving Princeton’s heritage as an evangelical college. According to McCosh, the “older men” among the trustees, faculty, and alumni “want a minister,” and on these grounds, the forty-five-year-old Patton seemed like a natural successor to McCosh. A native of Bermuda, Patton had graduated from University College of the University of Toronto; had attended Knox College, also of the University of Toronto; and had graduated from Princeton Theological Seminary in 1865. Ordained that same year in the Old School Presbyterian church, he served as pastor of a church in New York City. Cyrus H. McCormick (1809-1884), the farming machine magnate and patron of conservative Presbyterian causes, persuaded Patton to accept a position as the Professor of Didactic and Polemical Theology at the Presbyterian Seminary of the Northwest (later McCormick Theological Seminary) in Chicago in 1873.
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Arif, Yasmeen. "Bios, Pathos, and Life Emergent". En Life, Emergent. University of Minnesota Press, 2016. http://dx.doi.org/10.5749/minnesota/9781517900540.003.0006.
Resumen
The fifth and final chapter of Life, Emergent brings together the various strands of life and the social that have woven a swath of arguments that directs an excavation of life within an emphatic imagination of the social. This essay also approaches a reflection on the possible nature of a politics of and in life that the discussions so far lead to.
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Macías-Rojas, Patrisia. "The Citizen and the Criminal". En From Deportation to Prison. NYU Press, 2016. http://dx.doi.org/10.18574/nyu/9781479804665.003.0006.
Resumen
New enforcement targets and deployment of more border patrol to Arizona-Sonora border communities has inadvertently involved agents more directly in local crime control. This is the flip side to the more familiar scenario of local police and sheriffs who carry out immigration enforcement. This chapter considers the overreach of enforcement priorities and what some refer to as “net widening” in predominantly Latino border communities where border residents, mostly Mexican American citizens and legal permanent residents, are routinely arrested, prosecuted, sentenced, and, in some cases, deported for violations of immigration law.
Actas de conferencias sobre el tema "Directed patrol":
1
"Message from chief executive director/patron". En 2017 2nd IEEE International Conference on Recent Trends in Electronics, Information & Communication Technology (RTEICT). IEEE, 2017. http://dx.doi.org/10.1109/rteict.2017.8256538.
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Ling, Jiatong, Hang Zhang, Shaohua Dong y Jinheng Luo. "Intelligent Prevention Method for Third-Party Damage of Long-Distance Pipeline Based on Mobile Devices Location Information". En 2020 13th International Pipeline Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/ipc2020-9556.
Resumen
Abstract As one of the main risks of long-distance oil and gas pipelines, the consequences of pipeline accidents caused by third-party damage (TPD) are usually catastrophic. At present, TPD prevention approaches mainly include manual line patrol, fiber-optical vibration warning, and unmanned aerial vehicle (UAV) line patrol, but there are some limitations such as untimely warning, false alarm, and the missed report. As the location technology of mobile device matures, the user group provides massive data sources for the collection of location information, with which the tracks and features of the third-party activity along the pipeline can be directly obtained. Therefore, this paper proposes a method to identify the TPD behavior based on the location data of mobile devices. Firstly, the characteristics of relevant destruction behaviors were extracted from the historical destruction events. Then, the location information of the third-party activity near the target pipeline is obtained and the data is processed to remove the influence of noise, to reduce the computational burden of the subsequent identification process. Finally, calculate the difference degree of neighborhood trajectory and the similarity with the TPD features based on the data feature grouping (Difference feature and Similarity feature) to classify the type of third-party activity. Taking a 10km pipeline segment as an example, the method of this paper is used to preprocess the collected data and calculate the difference degree and similarity, 232 suspected TPD events are identified. After the on-site verification of the suspected damage by the line patrol, the results show that the method can better identify the third-party activities near the pipeline.
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Falzarano, Jeffrey M., Srinivas Vishnubhotla y Sarah E. Juckett. "Combined Steady State and Transient Analysis of a Patrol Vessel as Affected by Varying Amounts of Damping and Periodic and Random Wave Excitation". En ASME 2005 24th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2005. http://dx.doi.org/10.1115/omae2005-67578.
Resumen
Traditional naval architecture analysis of ship survival-ability involves analyzing the vessel righting arm curve in isolation or as compared to a steady wind heeling moment. It is well known that ships do not capsize in calm water and infinite time but do so in rough seas and do so dynamically in short time. Understanding the shortcomings of the traditional approach especially for advanced vessels numerous researchers in the ship dynamics field have proposed an alternative view of ship stability analysis, which involves dynamical analysis. Unfortunately, most ship motions analysis is linear and uses ideal flow theory both of which are inadequate descriptions of large amplitude ship rolling motion. Moreover, much of engineering nonlinear vibrations analysis involves perturbation methods where the nonlinearity is assumed small. Numerical simulation and physical model testing to find this critical behavior is time consuming and expensive. An alternative approach involves directly calculating critical behavior. This approach was originally developed for periodic forcing at a single frequency possibly the linear natural frequency. However, nonlinear resonance is much more complicated than linear resonance and more than a single frequency, multi-valued behavior can occur over a range of frequencies. Moreover, the phenomena which are possible for a nonlinear system are much more varied and diverse. In this paper we will analyze a traditional displacement hull form’s critical response in harmonic waves at the system’s linear natural frequency and compare this to the system’s critical response in random waves. We will compare these responses for different values of damping using these different analysis techniques.
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Fletcher, Richard y Muthu Chandrasekaran. "SmartBall™: A New Approach in Pipeline Leak Detection". En 2008 7th International Pipeline Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/ipc2008-64065.
Resumen
Early detection of leaks in hazardous materials pipelines is essential to reduce product loss and damage to the environment. Small undetected leaks can result in very high clean-up costs and have the potential to grow to more serious failures. There are a variety of methods that can detect leaks in pipelines, ranging from manual inspection to advanced satellite based imaging. Typically, most operators opt for a combination of CPM where available, and direct observation methodologies including aerial patrols, ground patrols and public awareness programs that are designed to encourage and facilitate the reporting of suspected leaks. Permanent monitoring sensors based on acoustic or other technologies are also available. These methods can be costly, and none can reliably detect small leaks regardless of their location in the line. SmartBall is a radical new approach that combines the sensitivity of acoustic leak detection with the 100% coverage capability of in-line inspection. The free-swimming device is spherical and smaller than the pipe bore allowing it to roll silently through the line and achieve the highest responsiveness to small leaks. It can be launched and retrieved using conventional pig traps, but its size and shape allow it to negotiate obstacles that could otherwise render a pipeline unpiggable. The SmartBall technology was originally developed and successfully implemented for the water industry, and now refined for oil and gas pipelines over 4-inches in diameter. SmartBall has been proven capable of detecting leaks in liquid lines of less than 0.1 gallons per minute where conventional CPM methods can detect leaks no smaller than 1% of throughput. Development work is continuing to reduce the detection threshold still further. Whereas traditional acoustic monitoring techniques have focused on longitudinal deployment and spacing of acoustic sensors, the SmartBall uses only a single acoustic sensor that is deployed inside the pipeline. Propelled by the flow of product in the pipeline, the device will record all noise events as it traverses the length of the pipeline. This allows the acoustic sensor to pass in very close proximity to any leak whereby the sensor can detect very small leaks, whose noise signature can be clearly distinguished from any background noise.
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Lee, Won Geun y David Montgomery. "Numerical Investigation of the Performance of a High Pressure Direct Injection (HPDI) Natural Gas Engine". En ASME 2014 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/icef2014-5681.
Resumen
High Pressure Direct-Injection (HPDI) is a technology option for engines used in mobile equipment applications where use of LNG as a fuel is desired. Using the combination of a diesel pilot injection and direct gas injection, HPDI has the potential to deliver low emissions, excellent transient performance, high efficiency, and high gas substitution. When the HPDI program was initially undertaken, in order to aid in initial hardware design, 3-dimensional computational fluid dynamic modeling was conducted to understand the mixing and reaction processes in the combustion chamber of an HPDI engine. Gaining insight into qualitative trends of operation parameters and hardware configurations was a first critical step toward delivering a hardware set to demonstrate HPDI natural gas combustion system capabilities. To model the combustion of multi-component fuel at arbitrary constituent ratios, a combustion model based on a detailed chemical kinetics approach was employed. Several published mechanisms and combinations of established mechanisms were tested by comparing results with existing fumigated dual fuel engine results. The result shows that some of combined mechanisms for n-heptane combustion and methane combustion are capable of adequately predicting combustion behavior in diesel-natural gas dual fuel combustion systems. One of the reduced n-heptane mechanisms (by Patel et al.) also matched dual fuel combustion results reasonably well. This preliminary simulation study was conducted with typical trapped air conditions and fuel quantities matching the energy delivery for a 100 % load condition in existing DI diesel engines. A full 360-degree mesh at intake valve closing was constructed and a detailed geometry of the gas injector nozzle and sac area was modeled in locally refined grids using a Caterpillar proprietary CFD code that accepts industry standard mechanisms. The diesel pilot injection followed by gas injection and resulting combustion inside an HPDI engine was simulated from IVC through the compression and combustion strokes. The operating parameters — such as diesel pilot injection timing, pilot injection amount, and start of gas injection — were varied, and the effect on IMEP, NOx, CO and cylinder pressure were investigated. It was shown that the start of gas injection is the strongest parameter for control of combustion. Subsequent to the work discussed in this paper, the hardware configuration established as optimal during the modeling work was carried forward to the physical engine testing and was successful in delivering the performance and emissions goals without modification, demonstrating the accuracy and value of modern combustion modeling.
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Goldstraw, M. W., C. Bil y C. Nicholson. "Aerodynamic Loads Prediction in an Integrated Computer-Based Conceptual Design Environment". En ASME/JSME 2003 4th Joint Fluids Summer Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/fedsm2003-45693.
Resumen
An important aspect of successful aircraft design is the concept of ‘right first time’, as any design changes downstream can be costly and may cause project delays. This is most applicable to the conceptual design phase. However, in the early stages of aircraft design, data is limited and prone to inaccuracies. Consequently, a design will typically traverse through a number of iterations, improving and refining with each step. Over the past 15 years, computer-based tools have become commonplace in aircraft design [1]. In general, most computer-based tools have been developed for the more advanced stages of the design process. For these tools to be useful in conceptual design, they must be user-friendly, interactive, and provide quick return times. A classic example is the aerodynamic load data required for structural design. Both are dependent on geometric parameters, which may still be subject to change. To complete the analysis within practical time constraints, a highly integrated and automated system is required [2, 3]. This paper presents such a system, developed using industry accepted software components including AutoCAD, VSAERO and MSC Nastran. This system allows an automatic, structured topology mesh to be generated from a basic three-view aircraft drawing, which inputs directly into VSAERO for loads calculations. The loads are subsequently transferred to MSC Patran as a pre-processor for structural analysis using MSC Nastran. If the result is unsatisfactory, the geometry or placement of structural components can easily be changed and the process repeated. The design environment was developed using FORTRAN90. The results of an application of this system to a simple wing, as well as a regional transport aircraft, are also presented.
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Pfliegler, G., J. Arnout, J. Kienast, K. Wittevrongel y J. Vermylen. "INSULIN RECEPTORS ARE NOT COUPLED TO THE PHOSPHOINOSITIDE OR ADENYLCYCLASE MESSENGER SYSTEMS IN HUMAN PLATELETS". En XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644523.
Resumen
Insulin receptors have been found not only on its “target Cells” but also on several other cell-types, including human platelets. From studies on adipocytes and liver cells it seems that they are coupled both to the adenylate cyclase-cyclic AMP and the polyphosphoinositide messenger systems. Circulating blood cells might faithfully reflect the insulin receptor state of target organ tissues. Impaired platelet function has an important role in the pathogenesis of vascular and thrombotic complications in diabetes mellitus, and insulin seems to act directly on platelets. A reduction in the number and binding capacity of platelet insulin receptors in diabetic patients (Udvardy et al. 1986) suggested a (patho)physiological role for these receptors. In our studies, insulin (1 × 10-9 - 1 × 10-6 M) did not affect basal platelet cyclic AMP levels, as measured following incorporation of [3H] adenine. Insulin did not prevent PGI2 (25-75 nmol/L) induced cyclic AMP formation in platelets. Insulin did not modify the basal levels of inositol phosphate (IP), IP2 or IP3 in platelets, as measured following incorporation of [3H] inositol. Insulin did not affect formation of IP, IP2 or IP3 by thrombin. No changes in cytosolic free Ca2+ (Quin 2 method) were detected in the presence of insulin. Sodium nitroprusside on the other hand, which is known to mimic several effects of insulin on adipocytes, inhibited IP formation induced by threshold concentrations of thrombin.On the basis of our results the insulin receptors in human platelets seem to be “non-functional” insofar as their occupancy is not accompanied by the stimulation or inhibition of phospho-inositide breakdown or cyclic AMP formation. Similarly, “silent” muscarinic-cholinergic receptors have recently been reported in human erythrocytes (Sehar et al. 1986).
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Giostri, Andrea, Claudio Saccilotto, Paolo Silva, Ennio Macchi y Giampaolo Manzolini. "A Numerical Model for Off-Design Performance Calculation of Parabolic Trough Based Solar Power Plants". En ASME 2010 4th International Conference on Energy Sustainability. ASMEDC, 2010. http://dx.doi.org/10.1115/es2010-90383.
Resumen
The paper deals with the development and testing of an innovative code for the performance prediction of solar trough based CSP plants in off-design conditions. The code is developed in MS Visual Basic 6.0 with Excel as user interface. The proposed code originates from a previously presented algorithm for on-design sizing and cost estimation of the solar field lay-out, as well as of the main components of the plant, including connecting piping and the steam cycle. Off-design calculation starts from data obtained through the on-design algorithm and considers steady-state situations. Both models are implemented in the same software, named PATTO (PArabolic Trough Thermodynamic Optimization), which is very flexible: the optical-thermal model of collectors can simulate different kinds of parabolic trough systems in commerce, including a combination of various mirrors, receivers and supports. The code is also flexible in terms of working fluid, temperature and pressure range, and can also simulate direct steam generation plants (DSG). Regarding the power block, a conventional steam cycle with super-heater, eventually a re-heater section, and up to seven regenerative bleedings is adopted. The off-design model calculates thermal performance of collectors taking into account proper correlations for convective heat transfer coefficients, considering also boiling regime in DSG configurations. Solar plant heat and mass balances and performances at off-design conditions are estimated by accounting for the constraints imposed by the available heat transfer areas in heat exchangers and condenser, as well as the characteristic curve of the steam turbine. The numerical model can be used for a single calculation in a specific off-design condition, as well as for a whole year estimation of energy balances with an hourly resolution. The model is tested towards real applications and reference values found in literature; in particular, focusing on SEGS VI plant in the USA and SAM® code. Annual energy balances with ambient condition taken from TMY3 database are obtained, showing good accuracy of predicted performances. The code potentiality in the design process reveals twofold: it can be used for plant optimization in feasibility studies; moreover it is useful to find the best control strategy of a plant, especially the mass flow of heat transfer fluid in each operating condition.
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Bevilacqua, M. A. y M. A. Gimbrone. "LEUKOCYTE-ENDOTHELIAL INTERACTIONS: IMPLICATIONS FOR INFLAMMATION AND COAGULATION". En XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642948.
Resumen
A rapidly increasing body of data indicates that the vascular endothelium plays an active role in the development of inflammatory and thrombotic processes. Our laboratory has focused on the modulation of certain endothelial cell functions by inflammatory/immune mediators. Initially, we demonstrated that human monocyte derived interleukin-1 (hmIL-1) can act directly on cultured human endothelial cells (HEC) to increase the expression of tissue factor procoagulant activity in a time- and protein-synthesis dependent fashion (J. Exp. Med. 160:618, 1984). Increased expression of HEC tissue factor was also elicited with recombinant IL-1α (rlL-lα), rIL-1 β, and recombinant human tumor necrosis factor (rTNF), as well as with bacterial endotoxin (1 ipopolysaccharide, LPS) (Am. J. Pathol. 121:393, 1985; Proc. Natl. Acad. Sci. USA 83:4533, 1986). The kinetics of the HEC tissue factor responses to these stimuli were similar, demonstrating a rapid use rise to peak activity at ~ 4 hr, and a decline toward basal levels by 24 hr. This characteristic decline in tissue factor PCA after prolonged incubation with IL-1 or TNF was accompanied by selective endothelial hyporesponsiveness to the initially stimulating monokine. Interestingly, the effects of IL-1 and TNF were found to be additive even at apparent maximal doses of the individual monokines. We have also examined the effects of IL-1 and other mediators on HEC production of fibrinolytic components (J. Clin. Invest. 78:587, 1986). HEC monolayers which had been treated for 24 hr with IL-1 or TNF exhibited decreased tissue type plasminogen activator (tPA) and increased plasminogen activator inhibitor (PAI) as assessed in functional and immunological assays. Thus, certain inflammatory mediators such as IL-1 and TNF can act on vascular endothelial cells to induce the expression of tissue factor in a rapid and transient fashion, and to decrease the expression of fibrinolytic activity in a more prolonged fashion. In a parallel series of studies, we have demonstrated that IL-1, TNF and LPS also act on HEC to increase the adhesion of polymorphonuclear leukocytes (PMN), monocytes and the related cell lines HL-60 and U937 (J. Clin. Invest. 76:2003, 1985; Fed. Proc. 46:405A, 1987). The kinetics of this modulation of HEC adhesiveness parallel that of the change in tissue factor PCA. Recently, we have developed two monoclonal antibodies (mAb), H4/18 and H18/7, which identify a surface antigen expressed on monokine- and LPS-stimulated HEC but not on unstimulated HEC. The mediator specificity, kinetics, and protein synthesis-dependence of the expression of this antigen correlate with increased HEC adhesiveness for leukocytes. Neither mAb binds to unstimulated or stimulated PMN, HL-60 cells or dermal fibroblasts. H18/7 inhibits the adhesion of PMN (>50%) and HL-60 cells (>60%) to stimulated HEC by comparison to isotype matched control mAb; H4/18 also inhibits HL-60 adhesion but to a lesser extent. H4/18 and H18/7 immunoprecipitate the same polypeptides from biosynthetically-1abeled monokine-stimulated HEC, but not unstimulated HEC. We have designated this inducible endothelial cell surface protein, endothelial-leukocyte adhesion molecule-1 (E-LAM 1). Thus, vascular endothelium can be activated by inflammatory/immune mediators to express both prothrombotic and pro-inflammatory functions. In vivo, these endothelial responses may contribute to a variety of pathophysiologic processes.
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Maxey, M. R., S. Dong, D. Liu y J. Xu. "Simulation of Particulate Flows With the Force-Coupling Method (Keynote Paper)". En ASME/JSME 2003 4th Joint Fluids Summer Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/fedsm2003-45713.
Resumen
One of the challenges in the numerical simulation of a system of particles in a fluid flow is to balance the need for an accurate representation of the flow around individual particles with the feasibility of simulating the fully-coupled dynamics of large numbers of particles. Over the past few years, several techniques have been developed for the direct numerical simulation of dispersed two-phase flows. Examples include the ALE-FEM formulation described by Hu et al. [1] and the DLM method of Patankar et al. [2]. The former uses a finite element mesh that conforms to the shape and position of each particle and evolves dynamically as the particles move, while the latter employs a fixed mesh and constraints are imposed in the volume of fluid occupied by the particle to reproduce a corresponding rigid body motion. In both the aim is to fully resolve the flow dynamics for each particle and there is a corresponding demand for high resolution of the flow. A typical approach used for gas-solid flows has been the point-force method that combines a Lagrangian tracking of individual particles with an Eulerian formulation for force feedback on the fluid flow. The latter approach has worked well for very small particles in systems of negligible void fraction but significant mass loading. The resolution level is very low and often the particles are smaller than the spacing between grid points. Its success comes from the averaging effect of large numbers of small particles and the fact that the influence of an individual particle is weak. The approach though is inaccurate for liquid-solid or bubbly flows when the individual particles are of finite size and the void fractions may easily be larger than 1%. In tracking the individual particles an equation of motion is formulated that relates the particle acceleration to the fluid forces acting on the particle, and these forces such as drag and lift are parameterized in terms of the local fluid velocity, velocity gradients and history of the fluid motion. Once flow modification is included however, it is harder to specify the local flow. The parameterizations also become more complex as effects of finite Reynolds number or wall boundaries are included. As a numerical procedure, the force-coupling method (FCM) does not require the same level of resolution as the DLM or ALE-FEM schemes and avoids the limitations of the point-force method. It gives a self-consistent scheme for simulating the dynamics of a system of small particle using a fixed numerical mesh and resolves the flow except close to the surface of each particle. Distributed, finite force-multipoles are used to represent the particles, and FCM is able to predict quite well the motion of isolated particles in shear flows and the interaction between moving particles. The method also provides insights into how the two-phase flow may be described theoretically and modeled. The idea of the force-coupling method was first introduced by Maxey et al. [3]. The basic elements of the method are given by Maxey & Patel [4] and Lomholt & Maxey [5]. In the basic version of the method, fluid is assumed to fill the whole flow domain, including the volume occupied by the particles. The presence of each particle is represented by a finite force monopole that generates a body force distribution f(x,t) on the fluid, which transmits the resultant force of the particles on the flow to the fluid. The velocity field u(x,t) is incompressible and satisfies ∇·u=0(1)ρDuDt=−∇p+μ∇2u+f(x,t),(2) where μ is the fluid viscosity and p is the pressure. The body force due to the presence of NP bubbles is f(x,t)=∑n=1NpF(n)Δ(x−Y(n)(t)),(3)Y(n)(t) is the position of the nth spherical particle and F(n)(t) is the force this exerts on the fluid. The force monopole for each particle is determined by the function Δ(x), which is specified as a Gaussian envelope Δ(x)=(2πσ2)−3/2exp(−x2/2σ2)(4) and the length scale σ is set in terms of the particle radius a as a/σ = π. The velocity of each particle V(n)(t) is found by forming a local average of the fluid velocity over the region occupied by the particle as V(n)(t)=∫u(x,t)Δ(x−Y(n)(t))d3x.(5) If mP and mF denote the mass of a particle and the mass of displaced fluid, the force of the particle acting on the fluid is F(n)=(mP−mF)(g−dV(n)dt).(6) This force is the sum of the net external force due to buoyancy of the particle and the excess inertia of the particle over the corresponding volume of displaced fluid. In addition a short-range, conservative force barrier is imposed to represent collisions between particles and prevent overlap. A similar barrier force is imposed, normal to the wall, to represent collisions between a particle and a rigid wall. With this scheme the body forces induce a fluid motion equivalent to that of the particles. The dynamics of the particles and the fluid are considered as one system where fluid drag on the particles, added-mass effects and lift forces are internal to the system. The method does not resolve flow details near to the surface of a particle, and indeed the no-slip condition is not satisfied on surface. At distances of about half a particle radius from the surface the flow though is fairly well represented. While there is no explicit boundary condition on the particle surface, the condition (5) ensures that the bubble and the surrounding fluid move together. The method has been applied to a variety of flow problems. Lomholt et al. [6] compared experimental results for the buoyant rise of particles in a vertical channel filled with liquid with results from corresponding simulations with FCM. The particle Reynolds numbers were in the range of 0 to 5 and the results agreed well. The wake-capture and the drafting, kissing and tumbling of pairs of particles, or of a group of three particles were found to match. Comparisons have made too with full direct numerical simulations performed with a spectral element code [7]. Liu et al. [8] examined the motion of particles in a channel at both low and finite Reynolds numbers, up to Re = 10. There was in general good agreement between the FCM results and the DNS for the particle motion, and the flow details were consistent away from the particle surface. There has been extensive work in the past on the sedimentation of particles in a homogeneous suspension, mainly for conditions of Stokes flow. Climent & Maxey [9] have verified that the FCM scheme reproduces many of the standard features found for Stokes suspensions. The results for finite Reynolds numbers illustrate how the structure of the suspension changes as fluid inertia is introduced, in particular limiting the growth in velocity fluctuation levels with system size. Further work has been done by Dance [10] on sedimenting suspensions in bounded containers. Recently we have been studying the dynamics of drag reduction by injecting micro-bubbles into a turbulent channel flow. This has been proven through experiments over the past 30 years to be an effective means for drag reduction but the details of the mechanisms involved have not been determined. Numerical simulations by Xu et al. [11] have shown clear evidence of drag reduction for a range of bubble sizes. A key feature is the need to maintain a concentration of bubbles in the near-wall region. In the talk, the method will be described and example results given. Specific issues relevant to gas-solid flows will be discussed.
Informes sobre el tema "Directed patrol":
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Sanguinet, Eduardo, Luis Armando Galvis-Aponte, Inácio F. Araújo y Eduardo A. Haddad. Viajeros urbanos de paseo por la playa: efectos regionales del turismo interno en Colombia. Banco de la República de Colombia, diciembre de 2020. http://dx.doi.org/10.32468/dtseru.293.
Resumen
En este documento se estudia el rol que juega el turismo interno como un mecanismo de transferencia interregional de ingresos. En Colombia, esos flujos siguen un patrón de origen en las regiones centrales y con destino en la periferia del país. Uno de los principales destinos turísticos es la costa Caribe, la cual presenta los indicadores socioeconómicos más críticos del país. La hipótesis que se plantea es que la inyección de recursos, a través del gasto en turismo, contribuye a generar efectos sistémicos en las regiones de destino. Existe poca evidencia empírica sobre estos impactos del turismo en Colombia, donde la mayoría de los estudios adoptan métodos cualitativos. Aquellos que usan técnicas cuantitativas no tienen en cuenta una aproximación sistémica para calcular impactos regionales. En este sentido, el objetivo de este trabajo es analizar los impactos regionales de los patrones de consumo del gasto de los turistas colombianos, enfocado en la región Caribe, haciendo uso de un modelo interregional insumo-producto, junto con datos de la Encuesta de Gasto en Turismo Interno (EGIT) 2014-2015. Los ejercicios desarrollados permiten capturar la contribución del turismo interno al crecimiento económico inclusivo en términos de las características socioeconómicas del empleo y la generación de ingresos, tanto directa como indirectamente. Esto es importante para proporcionar información para la formulación de políticas regionales relacionadas con el turismo. Los resultados sugieren que el turismo interno puede ser considerado como un canal importante para producir una asignación más eficiente de recursos y reducir la desigualdad entre las regiones de Colombia. Se concluye que las estrategias de política regional dirigidas al sector turístico pueden ser relevantes para el desarrollo del Caribe colombiano.