The purpose of this paper is to present the results of the development, at the Mechanical Metrolo... more The purpose of this paper is to present the results of the development, at the Mechanical Metrology Laboratory - IPT, the capability to calibrate load cells until 2MN in tension using the pyramidal method. This type of assembly in normally applied for compression. The goal is achieve an uncertainty of 0,05%.
Atrofia maxilar Injerto óseo Implantes dentales Reconstrucción 3D Técnica en túnel Elevación de s... more Atrofia maxilar Injerto óseo Implantes dentales Reconstrucción 3D Técnica en túnel Elevación de seno r e s u m e n Objetivos: En defectos maxilares con importante componente vertical, es necesaria la reconstrucción del proceso alveolar previamente a la rehabilitación con implantes para evitar una longitud desproporcionada de las coronas protésicas. En este artículo se revisa el tratamiento del maxilar posterior atrófico mediante elevación de seno y técnica de reconstrucción alveolar tridimensional simultánea con autoinjerto óseo. Se utilizó como vía de abordaje un túnel mucoso subperióstico a través de una incisión vertical única para prevenir los principales problemas de los injertos en aposición: la exposición y la reabsorción. Material y método: Se han evaluado retrospectivamente 12 atrofias maxilares posteriores tratadas con esta técnica de forma consecutiva entre enero de 2011 y julio de 2012. El reborde alveolar se reconstruyó hasta un mínimo de 6 mm de anchura a nivel crestal, incrementando su altura y disminuyendo la distancia interoclusal, para alcanzar el criterio de éxito establecido de fijación segura de implantes de, al menos, 3,8 y 11 mm de diámetro y longitud respectivamente. Resultados: La ganancia media ósea en altura fue de 4,54 mm. La cirugía de implantes se realizó hacia los 4 meses. Se colocaron 25 implantes con un 96% de éxito. El tiempo medio de seguimiento fue de 18 meses. Conclusiones: El tratamiento del sector posterior maxilar atrófico mediante reconstrucción tridimensional con autoinjerto óseo, elevación sinusal y abordaje por tunelización es una técnica que proporciona resultados predecibles y estables, permitiendo la rehabilitación con coronas sobre implantes dentales de dimensiones adecuadas.
Surgical Endoscopy and Other Interventional Techniques, 1999
Background: Some of the persistent problems associated with laparoscopic surgery stem from the in... more Background: Some of the persistent problems associated with laparoscopic surgery stem from the inability of the surgeon to palpate the abdominal contents during the operation. This lack of tactile sensation can lead to poor abdominal exploration, difficulty in extracting the organs, and a relatively long operation time compared to conventional procedures. The Dexterity Pneumo Sleeve is a new device that allows the surgeon to insert his or her hand into the abdominal cavity through a small incision while preserving the pneumoperitoneum. Methods: Recently, 13 of our patients underwent handassisted advanced laparoscopic surgery using this device. In this series, we had two cases of gastrectomy, two cases of gastric bypass for morbid obesity, two Whipple cases for periampullary tumor, and seven cases of bowel resection. On the basis of this series, we were able to assess the utility of this device. Results: Satisfactory pneumoperitoneum was maintained in 12 of 13 cases. The length of the skin incision was 7.8 cm on average, which was almost the same size as surgeon's glove. The device proved to be very useful for tissue retraction and abdominal exploration in all cases and for intracorporeal knot tying in some cases. Conclusions: We found that the device permitted an easier dissection, resection, and anastomosis. It also helped to decrease the operation time.
Journal of Laparoendoscopic & Advanced Surgical Techniques, 1997
Endoscopically sutured vascular anastomoses are complex, time consuming, and require great dexter... more Endoscopically sutured vascular anastomoses are complex, time consuming, and require great dexterity. We decided to evaluate performance enhancement using a robotic device to create sutured coronary artery bypass anastomoses with endoscopic techniques in a plastic model. Seven coronary artery bypass anastomoses were endoscopically created in a plastic model using a robotic enhancement technology (Computer Motion, Goleta, CA). Anastomoses were created with a single running suture (7-0 monofilament). Our endpoints were operative time, intraoperative incidents, stability and dexterity of the robotic system, surgeon's fatigue, and anastomotic patency. Operative time was 46+/-12 min (mean+/-SD). There were no intraoperative incidents. Patency was confirmed in all anastomoses. The system's stability and dexterity were high. Surgeon's fatigue was mild. The use of robotic enhancement technology leads to an efficient performance of sutured coronary artery bypass anastomoses in a plastic model. The robotic device enhances dexterity, precision, and reduces surgeon's fatigue while preserving the quality of hand suturing.
To compare the surgical performance of manual and robotically assisted laparoscopic instruments o... more To compare the surgical performance of manual and robotically assisted laparoscopic instruments on basic maneuvers and intracorporeal suturing in inanimate models. A set of laparoscopic tasks was used to evaluate basic endoscopic movements and intracorporeal suturing: positioning a cylinder on a Peg-Board, dropping beads into receptacles, running a 25-cm rope, and capping a hypodermic needle. Intracorporeal knot tying and running a suture through predetermined points were evaluated separately. The sutures used for these tasks were 2-0 and 4-0 silk and 6-0 and 7-0 polypropylene. Twenty surgeons completed the set of laparoscopic tasks manually and then with a robotically assisted system. None had used the robotic system before. Time required to complete the tasks and the precision in performing them. The robotic system accurately reproduced the movements of the surgeons and filtered their hand tremors efficiently. In the basic tasks, operative times were significantly longer for the robotic system (P<.001). In the suturing tasks, operative times were longer with the use of the robotic system for sutures sizes 2-0 and 4-0 (P<.001). However, time differences were not significant for suture sizes 6-0 and 7-0 (P> or =.07). Precision measurements were similar for all tasks using the manual instruments and the robotically assisted system. No significant differences were found between the performance of advanced laparoscopic surgeons and laparoscopic fellows. Laparoscopic maneuvering and suturing is faster and just as precise when performed manually as when performed with the prototype robotic system. These differences in speed are inversely proportional to the size of the suture. Future generations of the robotic system may eliminate these differences.
Iee Proceedings-generation Transmission and Distribution, 2002
The daVa of four networks that can be used in carrying out comparative studies with methods for t... more The daVa of four networks that can be used in carrying out comparative studies with methods for transmission network expansion planning are gwen. These networks are of various types and different levels of complexity. The main mathematical formulations used in transmission expansion studies-transportation models, hybrid models, DC power flow models, and disjunctive models are also SummdnSed and compared. The main algorithm families are reviewed-both analytical, cOmbinatOnd1 and heuristic approaches. Optimal solutions are not yet known for some of the four networks when more accurate models (e.g. the DC model) are used to represent the power flow equations-the state of the art with regard to this is also summarised. This should sewe as a challenge to authors searching for new, more efficient methods. IEE ProcmLp.s online no. 2W20026 DO/: K.lM9/ip-ptdZMl2W26 Paper first received 14th March 2001 R. Romero is with the Faculty of Enpineefins of llha Solteira, Paulista Swte University. CP 31, Ilha Soltririr 15385-NX1, SP, Brazil A. Monticelli and A. Garcia are with the Departmcnl of Electric Enersy Systems. University of Campinas, CP 6101, Campinns 13081-970. SP. Brazil S. Hafiner is with the Depaitmeni of EImtfimudl Enginee~ing. Pontifical Catholic University of Rio Grande do SUI. CP 1429. Port0 Alepre 90619-9INl RS, Brazil stages of the planning process when the most attractive topologies have been determined.
The authors discuss the modeling of branches with zero impedances in power system state estimatio... more The authors discuss the modeling of branches with zero impedances in power system state estimation. A new modeling approach is introduced by means of which zero impedance branches can be modeled exactly. An overview of the state estimation problem is presented using two formulations: the standard normal equations and the extended form of the normal equations in which zero injections
IEEE Transactions on Power Apparatus and Systems, 1979
... Here, the Jacobian matrix H and the gain matrix G are tS =oaxl x k (5) ax x = x and G = Ht(xk... more ... Here, the Jacobian matrix H and the gain matrix G are tS =oaxl x k (5) ax x = x and G = Ht(xk) W H(xk) (6) ... A version that introduces approximations in the right-hand side of equation (4) was presented by Aschmoneit, Denzel, Graf and Schellstede5; this version was ap-...
121. Load flow sensitivity for node injections and system param¬ eters 121. Increase or decrease ... more 121. Load flow sensitivity for node injections and system param¬ eters 121. Increase or decrease of stored energy of the elements and C in the electric power system due to a small frequency disturbance raise
The purpose of this paper is to present the results of the development, at the Mechanical Metrolo... more The purpose of this paper is to present the results of the development, at the Mechanical Metrology Laboratory - IPT, the capability to calibrate load cells until 2MN in tension using the pyramidal method. This type of assembly in normally applied for compression. The goal is achieve an uncertainty of 0,05%.
Atrofia maxilar Injerto óseo Implantes dentales Reconstrucción 3D Técnica en túnel Elevación de s... more Atrofia maxilar Injerto óseo Implantes dentales Reconstrucción 3D Técnica en túnel Elevación de seno r e s u m e n Objetivos: En defectos maxilares con importante componente vertical, es necesaria la reconstrucción del proceso alveolar previamente a la rehabilitación con implantes para evitar una longitud desproporcionada de las coronas protésicas. En este artículo se revisa el tratamiento del maxilar posterior atrófico mediante elevación de seno y técnica de reconstrucción alveolar tridimensional simultánea con autoinjerto óseo. Se utilizó como vía de abordaje un túnel mucoso subperióstico a través de una incisión vertical única para prevenir los principales problemas de los injertos en aposición: la exposición y la reabsorción. Material y método: Se han evaluado retrospectivamente 12 atrofias maxilares posteriores tratadas con esta técnica de forma consecutiva entre enero de 2011 y julio de 2012. El reborde alveolar se reconstruyó hasta un mínimo de 6 mm de anchura a nivel crestal, incrementando su altura y disminuyendo la distancia interoclusal, para alcanzar el criterio de éxito establecido de fijación segura de implantes de, al menos, 3,8 y 11 mm de diámetro y longitud respectivamente. Resultados: La ganancia media ósea en altura fue de 4,54 mm. La cirugía de implantes se realizó hacia los 4 meses. Se colocaron 25 implantes con un 96% de éxito. El tiempo medio de seguimiento fue de 18 meses. Conclusiones: El tratamiento del sector posterior maxilar atrófico mediante reconstrucción tridimensional con autoinjerto óseo, elevación sinusal y abordaje por tunelización es una técnica que proporciona resultados predecibles y estables, permitiendo la rehabilitación con coronas sobre implantes dentales de dimensiones adecuadas.
Surgical Endoscopy and Other Interventional Techniques, 1999
Background: Some of the persistent problems associated with laparoscopic surgery stem from the in... more Background: Some of the persistent problems associated with laparoscopic surgery stem from the inability of the surgeon to palpate the abdominal contents during the operation. This lack of tactile sensation can lead to poor abdominal exploration, difficulty in extracting the organs, and a relatively long operation time compared to conventional procedures. The Dexterity Pneumo Sleeve is a new device that allows the surgeon to insert his or her hand into the abdominal cavity through a small incision while preserving the pneumoperitoneum. Methods: Recently, 13 of our patients underwent handassisted advanced laparoscopic surgery using this device. In this series, we had two cases of gastrectomy, two cases of gastric bypass for morbid obesity, two Whipple cases for periampullary tumor, and seven cases of bowel resection. On the basis of this series, we were able to assess the utility of this device. Results: Satisfactory pneumoperitoneum was maintained in 12 of 13 cases. The length of the skin incision was 7.8 cm on average, which was almost the same size as surgeon's glove. The device proved to be very useful for tissue retraction and abdominal exploration in all cases and for intracorporeal knot tying in some cases. Conclusions: We found that the device permitted an easier dissection, resection, and anastomosis. It also helped to decrease the operation time.
Journal of Laparoendoscopic & Advanced Surgical Techniques, 1997
Endoscopically sutured vascular anastomoses are complex, time consuming, and require great dexter... more Endoscopically sutured vascular anastomoses are complex, time consuming, and require great dexterity. We decided to evaluate performance enhancement using a robotic device to create sutured coronary artery bypass anastomoses with endoscopic techniques in a plastic model. Seven coronary artery bypass anastomoses were endoscopically created in a plastic model using a robotic enhancement technology (Computer Motion, Goleta, CA). Anastomoses were created with a single running suture (7-0 monofilament). Our endpoints were operative time, intraoperative incidents, stability and dexterity of the robotic system, surgeon's fatigue, and anastomotic patency. Operative time was 46+/-12 min (mean+/-SD). There were no intraoperative incidents. Patency was confirmed in all anastomoses. The system's stability and dexterity were high. Surgeon's fatigue was mild. The use of robotic enhancement technology leads to an efficient performance of sutured coronary artery bypass anastomoses in a plastic model. The robotic device enhances dexterity, precision, and reduces surgeon's fatigue while preserving the quality of hand suturing.
To compare the surgical performance of manual and robotically assisted laparoscopic instruments o... more To compare the surgical performance of manual and robotically assisted laparoscopic instruments on basic maneuvers and intracorporeal suturing in inanimate models. A set of laparoscopic tasks was used to evaluate basic endoscopic movements and intracorporeal suturing: positioning a cylinder on a Peg-Board, dropping beads into receptacles, running a 25-cm rope, and capping a hypodermic needle. Intracorporeal knot tying and running a suture through predetermined points were evaluated separately. The sutures used for these tasks were 2-0 and 4-0 silk and 6-0 and 7-0 polypropylene. Twenty surgeons completed the set of laparoscopic tasks manually and then with a robotically assisted system. None had used the robotic system before. Time required to complete the tasks and the precision in performing them. The robotic system accurately reproduced the movements of the surgeons and filtered their hand tremors efficiently. In the basic tasks, operative times were significantly longer for the robotic system (P<.001). In the suturing tasks, operative times were longer with the use of the robotic system for sutures sizes 2-0 and 4-0 (P<.001). However, time differences were not significant for suture sizes 6-0 and 7-0 (P> or =.07). Precision measurements were similar for all tasks using the manual instruments and the robotically assisted system. No significant differences were found between the performance of advanced laparoscopic surgeons and laparoscopic fellows. Laparoscopic maneuvering and suturing is faster and just as precise when performed manually as when performed with the prototype robotic system. These differences in speed are inversely proportional to the size of the suture. Future generations of the robotic system may eliminate these differences.
Iee Proceedings-generation Transmission and Distribution, 2002
The daVa of four networks that can be used in carrying out comparative studies with methods for t... more The daVa of four networks that can be used in carrying out comparative studies with methods for transmission network expansion planning are gwen. These networks are of various types and different levels of complexity. The main mathematical formulations used in transmission expansion studies-transportation models, hybrid models, DC power flow models, and disjunctive models are also SummdnSed and compared. The main algorithm families are reviewed-both analytical, cOmbinatOnd1 and heuristic approaches. Optimal solutions are not yet known for some of the four networks when more accurate models (e.g. the DC model) are used to represent the power flow equations-the state of the art with regard to this is also summarised. This should sewe as a challenge to authors searching for new, more efficient methods. IEE ProcmLp.s online no. 2W20026 DO/: K.lM9/ip-ptdZMl2W26 Paper first received 14th March 2001 R. Romero is with the Faculty of Enpineefins of llha Solteira, Paulista Swte University. CP 31, Ilha Soltririr 15385-NX1, SP, Brazil A. Monticelli and A. Garcia are with the Departmcnl of Electric Enersy Systems. University of Campinas, CP 6101, Campinns 13081-970. SP. Brazil S. Hafiner is with the Depaitmeni of EImtfimudl Enginee~ing. Pontifical Catholic University of Rio Grande do SUI. CP 1429. Port0 Alepre 90619-9INl RS, Brazil stages of the planning process when the most attractive topologies have been determined.
The authors discuss the modeling of branches with zero impedances in power system state estimatio... more The authors discuss the modeling of branches with zero impedances in power system state estimation. A new modeling approach is introduced by means of which zero impedance branches can be modeled exactly. An overview of the state estimation problem is presented using two formulations: the standard normal equations and the extended form of the normal equations in which zero injections
IEEE Transactions on Power Apparatus and Systems, 1979
... Here, the Jacobian matrix H and the gain matrix G are tS =oaxl x k (5) ax x = x and G = Ht(xk... more ... Here, the Jacobian matrix H and the gain matrix G are tS =oaxl x k (5) ax x = x and G = Ht(xk) W H(xk) (6) ... A version that introduces approximations in the right-hand side of equation (4) was presented by Aschmoneit, Denzel, Graf and Schellstede5; this version was ap-...
121. Load flow sensitivity for node injections and system param¬ eters 121. Increase or decrease ... more 121. Load flow sensitivity for node injections and system param¬ eters 121. Increase or decrease of stored energy of the elements and C in the electric power system due to a small frequency disturbance raise
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