390 resultados para minimal occlusive volume technique


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Today’s highly competitive market influences the manufacturing industry to improve their production systems to become the optimal system in the shortest cycle time as possible. One of most common problems in manufacturing systems is the assembly line balancing problem. The assembly line balancing problem involves task assignments to workstations with optimum line efficiency. The line balancing technique, namely “COMSOAL”, is an abbreviation of “Computer Method for Sequencing Operations for Assembly Lines”. Arcus initially developed the COMSOAL technique in 1966 [1], and it has been mainly applied to solve assembly line balancing problems [6]. The most common purposes of COMSOAL are to minimise idle time, optimise production line efficiency, and minimise the number of workstations. Therefore, this project will implement COMSOAL to balance an assembly line in the motorcycle industry. The new solution by COMSOAL will be used to compare with the previous solution that was developed by Multi‐Started Neighborhood Search Heuristic (MSNSH), which will result in five aspects including cycle time, total idle time, line efficiency, average daily productivity rate, and the workload balance. The journal name “Optimising and simulating the assembly line balancing problem in a motorcycle manufacturing company: a case study” will be used as the case study for this project [5].

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A Flash Event (FE) represents a period of time when a web-server experiences a dramatic increase in incoming traffic, either following a newsworthy event that has prompted users to locate and access it, or as a result of redirection from other popular web or social media sites. This usually leads to network congestion and Quality-of-Service (QoS) degradation. These events can be mistaken for Distributed Denial-of-Service (DDoS) attacks aimed at disrupting the server. Accurate detection of FEs and their distinction from DDoS attacks is important, since different actions need to be undertaken by network administrators in these two cases. However, lack of public domain FE datasets hinders research in this area. In this paper we present a detailed study of flash events and classify them into three broad categories. In addition, the paper describes FEs in terms of three key components: the volume of incoming traffic, the related source IP-addresses, and the resources being accessed. We present such a FE model with minimal parameters and use publicly available datasets to analyse and validate our proposed model. The model can be used to generate different types of FE traffic, closely approximating real-world scenarios, in order to facilitate research into distinguishing FEs from DDoS attacks.

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Client owners usually need an estimate or forecast of their likely building costs in advance of detailed design in order to confirm the financial feasibility of their projects. Because of their timing in the project life cycle, these early stage forecasts are characterized by the minimal amount of information available concerning the new (target) project to the point that often only its size and type are known. One approach is to use the mean contract sum of a sample, or base group, of previous projects of a similar type and size to the project for which the estimate is needed. Bernoulli’s law of large numbers implies that this base group should be as large as possible. However, increasing the size of the base group inevitably involves including projects that are less and less similar to the target project. Deciding on the optimal number of base group projects is known as the homogeneity or pooling problem. A method of solving the homogeneity problem is described involving the use of closed form equations to compare three different sampling arrangements of previous projects for their simulated forecasting ability by a cross-validation method, where a series of targets are extracted, with replacement, from the groups and compared with the mean value of the projects in the base groups. The procedure is then demonstrated with 450 Hong Kong projects (with different project types: Residential, Commercial centre, Car parking, Social community centre, School, Office, Hotel, Industrial, University and Hospital) clustered into base groups according to their type and size.

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Fast calculation of quantities such as in-cylinder volume and indicated power is important in internal combustion engine research. Multiple channels of data including crank angle and pressure were collected for this purpose using a fully instrumented diesel engine research facility. Currently, existing methods use software to post-process the data, first calculating volume from crank angle, then calculating the indicated work and indicated power from the area enclosed by the pressure-volume indicator diagram. Instead, this work investigates the feasibility of achieving real-time calculation of volume and power via hardware implementation on Field Programmable Gate Arrays (FPGAs). Alternative hardware implementations were investigated using lookup tables, Taylor series methods or the CORDIC (CoOrdinate Rotation DIgital Computer) algorithm to compute the trigonometric operations in the crank angle to volume calculation, and the CORDIC algorithm was found to use the least amount of resources. Simulation of the hardware based implementation showed that the error in the volume and indicated power is less than 0.1%.

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Background: Pregnant women find themselves subject to comments and questions from people in public areas. Normally, becoming ‘public property’ is considered friendly and is relatively easy for pregnant women to deal with. However, following diagnosis of a fetal anomaly, the experience of being public property can exacerbate the emotional turmoil experienced by couples. Original research question: What is the experience of couples who continue pregnancy following the diagnosis of a fetal anomaly? Method: The study used an interpretive design informed by Merleau-Ponty and this paper reports on a subset of findings. Thirty-one interviews with pregnant women and their partners were undertaken following the diagnosis of a serious or lethal fetal anomaly. Women were between 25 and 38 weeks gestation at the time of their first interview. The non-directive interviews were audiotaped, transcribed verbatim and the transcripts were thematically analysed. Findings: A prominent theme that emerged during data analysis was that pregnancy is embodied therefore physically evident and ‘public’. Women found it difficult to deal with being public property when the fetus had a serious or lethal anomaly. Some women avoided social situations; others did not disclose the fetal condition but gave minimal or avoidant answers to minimise distress to themselves and others. The male participants were not visibly pregnant and they could continue life in public without being subject to the public’s gaze, but they were very aware and concerned about its impact on their partner. Conclusion: The public tend to assume that pregnancy is normal and will produce a healthy baby. This becomes problematic for women who have a fetus with an anomaly. Women use strategies to help them cope with becoming public property during pregnancy. Midwives can play an important role in reducing the negative consequences of a woman becoming public property following the diagnosis of a fetal anomaly.

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Purpose: To assess the effects of pre-cooling volume on neuromuscular function and performance in free-paced intermittent-sprint exercise in the heat. Methods: Ten male, teamsport athletes completed four randomized trials involving an 85-min free-paced intermittentsprint exercise protocol in 33°C±33% relative humidity. Pre-cooling sessions included whole body (WB), head+hand (HH), head (H) and no cooling (CONT), applied for 20-min pre-exercise and 5-min mid exercise. Maximal voluntary contractions (MVC) were assessed pre- and postintervention and mid- and post-exercise. Exercise performance was assessed with sprint times, % decline and distances covered during free-paced bouts. Measures of core(Tc) and skin (Tsk) temperatures, heart rate, perceptual exertion and thermal stress were monitored throughout. Venous and capillary blood was analyzed for metabolite, muscle damage and inflammatory markers. Results: WB pre-cooling facilitated the maintenance of sprint times during the exercise protocol with reduced % decline (P=0.04). Mean and total hard running distances increased with pre cooling 12% compared to CONT (P<0.05), specifically, WB was 6-7% greater than HH (P=0.02) and H (P=0.001) respectively. No change was evident in mean voluntary or evoked force pre- to post-exercise with WB and HH cooling (P>0.05). WB and HH cooling reduced Tc by 0.1-0.3°C compared to other conditions (P<0.05). WB Tsk was suppressed for the entire session(P=0.001). HR responses following WB cooling were reduced(P=0.05; d=1.07) compared to CONT conditions during exercise. Conclusion: A relationship between pre-cooling volume and exercise performance seems apparent, as larger surface area coverage augmented subsequent free-paced exercise capacity, in conjunction with greater suppression of physiological load. Maintenance of MVC with pre-cooling, despite increased work output suggests the role of centrally-mediated mechanisms in exercise pacing regulation and subsequent performance.

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An iterative based strategy is proposed for finding the optimal rating and location of fixed and switched capacitors in distribution networks. The substation Load Tap Changer tap is also set during this procedure. A Modified Discrete Particle Swarm Optimization is employed in the proposed strategy. The objective function is composed of the distribution line loss cost and the capacitors investment cost. The line loss is calculated using estimation of the load duration curve to multiple levels. The constraints are the bus voltage and the feeder current which should be maintained within their standard range. For validation of the proposed method, two case studies are tested. The first case study is the semi-urban 37-bus distribution system which is connected at bus 2 of the Roy Billinton Test System which is located in the secondary side of a 33/11 kV distribution substation. The second case is a 33 kV distribution network based on the modification of the 18-bus IEEE distribution system. The results are compared with prior publications to illustrate the accuracy of the proposed strategy.

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Purpose Endotracheal suctioning causes significant lung derecruitment. Closed suction (CS) minimizes lung volume loss during suction, and therefore, volumes are presumed to recover more quickly postsuctioning. Conflicting evidence exists regarding this. We examined the effects of open suction (OS) and CS on lung volume loss during suctioning, and recovery of end-expiratory lung volume (EELV) up to 30 minutes postsuction. Material and Methods Randomized crossover study examining 20 patients postcardiac surgery. CS and OS were performed in random order, 30 minutes apart. Lung impedance was measured during suction, and end-expiratory lung impedance was measured at baseline and postsuctioning using electrical impedance tomography. Oximetry, partial pressure of oxygen in the alveoli/fraction of inspired oxygen ratio and compliance were collected. Results Reductions in lung impedance during suctioning were less for CS than for OS (mean difference, − 905 impedance units; 95% confidence interval [CI], − 1234 to –587; P < .001). However, at all points postsuctioning, EELV recovered more slowly after CS than after OS. There were no statistically significant differences in the other respiratory parameters. Conclusions Closed suctioning minimized lung volume loss during suctioning but, counterintuitively, resulted in slower recovery of EELV postsuction compared with OS. Therefore, the use of CS cannot be assumed to be protective of lung volumes postsuctioning. Consideration should be given to restoring EELV after either suction method via a recruitment maneuver.

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The use of Trusted Platform Module (TPM) is be- coming increasingly popular in many security sys- tems. To access objects protected by TPM (such as cryptographic keys), several cryptographic proto- cols, such as the Object Specific Authorization Pro- tocol (OSAP), can be used. Given the sensitivity and the importance of those objects protected by TPM, the security of this protocol is vital. Formal meth- ods allow a precise and complete analysis of crypto- graphic protocols such that their security properties can be asserted with high assurance. Unfortunately, formal verification of these protocols are limited, de- spite the abundance of formal tools that one can use. In this paper, we demonstrate the use of Coloured Petri Nets (CPN) - a type of formal technique, to formally model the OSAP. Using this model, we then verify the authentication property of this protocol us- ing the state space analysis technique. The results of analysis demonstrates that as reported by Chen and Ryan the authentication property of OSAP can be violated.

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Filtration using granular media such as quarried sand, anthracite and granular activated carbon is a well-known technique used in both water and wastewater treatment. A relatively new prefiltration method called pebble matrix filtration (PMF) technology has been proved effective in treating high turbidity water during heavy rain periods that occur in many parts of the world. Sand and pebbles are the principal filter media used in PMF laboratory and pilot field trials conducted in the UK, Papua New Guinea and Serbia. However during first full-scale trials at a water treatment plant in Sri Lanka in 2008, problems were encountered in sourcing the required uniform size and shape of pebbles due to cost, scarcity and Government regulations on pebble dredging. As an alternative to pebbles, hand-made clay pebbles (balls) were fired in a kiln and their performance evaluated for the sustainability of the PMF system. These clay balls within a filter bed are subjected to stresses due to self-weight and overburden, therefore, it is important that clay balls should be able to withstand these stresses in water saturated conditions. In this paper, experimentally determined physical properties including compression failure load (Uniaxial Compressive Strength) and tensile strength at failure (theoretical) of hand-made clay balls are described. Hand-made clay balls fired between the kiln temperatures of 875oC to 960oC gave failure loads of between 3.0 kN and 7.1 kN. In another test when clay balls were fired to 1250oC the failure load was 35.0 kN compared to natural Scottish cobbles with an average failure load of 29.5 kN. The uniaxial compressive strength of clay balls obtained by experiment has been presented in terms of the tensile yield stress of clay balls. Based on the effective stress principle in soil mechanics, a method for the estimation of maximum theoretical load on clay balls used as filter media is proposed and compared with experimental failure loads.

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Conference curatorial outline The focus of this symposium was to question whether interior design is changing relative to local conditions, and the effect globalization has on the performance of regional, particularly Southern hemisphere identities. The intention being to understand how theory and practice is transposed to ‘distant lands’, and how ideas shift from one place to another. To this extent the symposium invited papers on the export, translation and adoption of theories and practices of interior design to differing climates, cultures, and landscapes. This process, sometimes referred to as a shift from ‘the centre to the margins’, seeks new perspectives on the adoption of European and US design ideas abroad, as well as their return to their place of origin. Papers were invited from a range of perspectives including the export of ideas/attitudes to interior spaces, history of interior spaces abroad, and the adoption of ideas/processes to new conditions. Paralleling this trafficking of ideas are broader observations about interior space that emerge through specificity of place. These include new and emerging directions and differences in our understanding of interiority; both real and virtual, and an ever-changing relationship to city, suburb and country. Keeping within the Symposium theme the intention was to examine other places, particularly on the margins of the discipline’s domain. Semantic slippage aside, there are a range of approaches that engage outside events and practices enabling a transdisciplinary practice that draws from other philosophical and theoretical frameworks. Moreover as the field expands and new territories are opened up, the virtual worlds of computer gaming, animations, and interactive environments, both rely on and produce new forms of expression. This raises questions about the extent such spaces adopt or translate existing theory and practice, that is the transposition from one area to another and their return to the discipline.

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Use of focus groups as a technique of inquiry is gaining attention in the area of health-care research. This paper will report on the technique of focus group interviewing to investigate the role of the infection control practitioner. Infection control is examined as a specialty area of health-care practice that has received little research attention to date. Additionally, it is an area of practice that is expanding in response to social, economic and microbiological forces. The focus group technique in this study helped a group of infection control practitioners from urban, regional and rural areas throughout Queensland identify and categorise their daily work activities. The outcomes of this process were then analysed to identify the growth in breadth and complexity of the role of the infection control practitioner in the contemporary health-care environment. Findings indicate that the role of the infection control practitioner in Australia has undergone changes consistent with and reflecting changing models of health-care delivery.

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The ability to accurately predict the remaining useful life of machine components is critical for machine continuous operation, and can also improve productivity and enhance system safety. In condition-based maintenance (CBM), maintenance is performed based on information collected through condition monitoring and an assessment of the machine health. Effective diagnostics and prognostics are important aspects of CBM for maintenance engineers to schedule a repair and to acquire replacement components before the components actually fail. All machine components are subjected to degradation processes in real environments and they have certain failure characteristics which can be related to the operating conditions. This paper describes a technique for accurate assessment of the remnant life of machines based on health state probability estimation and involving historical knowledge embedded in the closed loop diagnostics and prognostics systems. The technique uses a Support Vector Machine (SVM) classifier as a tool for estimating health state probability of machine degradation, which can affect the accuracy of prediction. To validate the feasibility of the proposed model, real life historical data from bearings of High Pressure Liquefied Natural Gas (HP-LNG) pumps were analysed and used to obtain the optimal prediction of remaining useful life. The results obtained were very encouraging and showed that the proposed prognostic system based on health state probability estimation has the potential to be used as an estimation tool for remnant life prediction in industrial machinery.