BACKGROUND Root canal shaping without any procedural error is of the utmost preference. Therefore, the purpose of this study was to use micro-computed tomography to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files. MATERIAL AND METHODS Sixty extracted upper second premolars were selected and were divided into 2 groups of 30. Be...

BACKGROUND The accessibility to health centers is a limitation to the use of preventive and curative health centers. AIM To assess geographic accessibility using a parameter that integrates information about the use of preventive services and travelling time from home to the health center. MATERIAL AND METHODS We analyzed target geographical areas of 10 community centers located at the Nort...

Most U.S. energy usage is for electricity production and vehicle transportation, two interdependent infrastructures. The strength and number of the interdependencies will increase rapidly as hybrid electric transportation systems, including plug-in hybrid electric vehicles and hybrid electric trains, become more prominent. There are several new energy supply technologies reaching maturity, acce...

The transportation of hazardous materials such as gasoline has unique features due to the nature of these type of materials and the importance role of these material in human life. Therefore, determining the routing of these materials is more challengeable than non-hazardous one due to more dangerous and risky condition besides the transportation costs. Since the distribution of gasoline take p...

A value chain is a series of events that takes a raw material and with each step adds value to it. Global interest in the application of natural gas (NG) in production and transportation has grown dramatically, representing a long-term, low-cost, domestic, and secure alternative to petroleum-based fuels. Many technological solutions are currently considered on the market or in development, whic...

This paper presents a new mathematical model for a production system through a scheduling problem considering a material handling system as an intelligent transportation system by automated guided vehicles (AGVs). The traditional systems cannot respond to the changes and customer’s demands and for this reason, a flexible production system is used. Therefore, for this purpose, automated transpor...

BACKGROUND This study aimed to compare glide path preparation of different pathfinding systems and their effects on the apical transportation of ProTaper Next (Dentsply Maillefer, Ballaigues, Switzerland) in mesial root canals of extracted human mandibular molars, using digital subtraction radiography. MATERIAL AND METHODS The mesial canals of 40 mandibular first molars (with curvature angles...

PURPOSE Comparison of TB incidence in young and middle age group between urban/surrounding area and other area. MATERIAL & METHODS TB incidence in young and middle age group by sex, nationality, labor status and prefecture is calculated with data of National Population Survey and TB surveillance in 2005. Risk factors of TB infection/break down such as public transportation, poverty, populatio...

Recently, the Value-at-Risk (VaR) framework was introduced for the routing problem of a single hazmat trip. In this paper, we extend the VaR framework in two important ways. First, we show how to apply the VaR concept to a more realistic multi-trip multi-hazmat type framework, which determines routes that minimize the global VaR value while satisfying equity constraints. Second, we show how to ...

IN T R O D U C T IO N U tiliz ing the m ethods of Price, Schm idt, and Davis in V irg in ia (1), it is feasible to estim ate expected hazardous m aterial highw ay accident frequencies for the State of Indiana. Politicians, adm inistrators, and those otherwise interested in rendering the threat posed by hazardous m aterial highw ay transporta tion som ew hat m ore intelligible m ay find it of va...