Analysis of topology aggregation techniques for QoS routing

We study and compare topology aggregation techniques used in QoS routing. Topology Aggregation (TA) is defined as a set of techniques that abstract or summarize the state information about the network topology to be exchanged, processed, and maintained by network nodes for routing purposes. Due to scalability, aggregation techniques have been an integral part of some routing protocols. However, TA has not been studied extensively except in a rather limited context. With the continuing growth of the Internet, scalability issues of QoS routing have been gaining importance. Therefore, we survey the current TA techniques, provide methodology to classify, evaluate, and compare their complexities and efficiencies. ©2007 ACM.postprin

Optimization of the load-and-haul operation at an opencast colliery

The current coal mining climate is characterized by coal price volatility, political instability, high labour costs, and increasing operational costs. This is exacerbated by a steady decline in the growth of global coal demand due to the increased use of alternative and renewable fuels in the energy industry. Locally, the overall mining cost inflation indices shows a yearly increase of 2% over the national consumer inflation. In order for coal mines to survive and mine profitably, they need to capitalize on the opportunity to improve their productivity and focus on one factor they can control: operational efficiency. Increasing productivity is one of the key drivers to counter diminishing profit margins. Increasing production effectively reduces operating costs. However, the emphasis should not only be on increasing output with the same input, but increasing the output while decreasing the input, and ultimately adding optimum value to current resources. Research shows that an increase in production will ultimately decrease the operation’s unit cost, especially fixed costs. In this study a load-and-haul fleet optimization approach has been used to identify the opportunities for operational improvement at an opencast colliery. The study combines the results of a literature review, on-site time studies, and statistical data analysis in order to determine the best loadertruck fleet combinations for increased production. Several relevant key performance indicators (KPIs) for the evaluation and identification of productivity improvement opportunities were defined during this study. These KPIs are bucket fill factor, loading conditions, loading cycle time, utilization, and deviations from schedule. The priority delays determined by on-site time studies compared to the time book for each delay showed that idle or waiting time by the loaders, face preparation and relocation, and process delays had significant deviations. However, the results showed that this operation is under-trucked, hence optimizing the loader-related inputs proved less effective than optimizing truck-related inputs. The results indicated that a homogeneous truck fleet consisting of five Caterpillar 789C trucks, combined with a Caterpillar 994K loader, is the most efficient fleet option and will produce 1455 t/h. The combined optimized effect of each identified KPI of production led to a tonnage improvement opportunity of 5421 t per shift.http://www.saimm.co.za/journal-papersam2018Mining Engineerin

Encaminhamento óptimo do tráfego em redes Triple Play

A Internet é responsável pelo surgimento de um novo paradigma de televisão – IPTV (Televisão sobre IP). Este serviço distingue-se de outros modelos de televisão, pois permite aos utilizadores um elevado grau de interactividade, com um controlo personalizado sobre os conteúdos a que pretende assistir. Possibilita ainda a oferta de um número ilimitado de canais, bem como o acesso a conteúdos de Vídeo on Demand (VoD). O IPTV apresenta diversas funcionalidades suportadas por uma arquitectura complexa e uma rede convergente que serve de integração a serviços de voz, dados e vídeo. A tecnologia IPTV explora ao máximo as características da Internet, com a utilização de mecanismos de Qualidade de Serviço. Surge ainda como uma revolução dentro do panorama televisivo, abrindo portas a novos investimentos por parte das empresas de telecomunicações. A Internet também permite fazer chamadas telefónicas sobre a rede IP. Este serviço é denominado VoIP (Voz sobre IP) e encontra-se em funcionamento já há algum tempo. Desta forma surge a oportunidade de poder oferecer ao consumidor final, um serviço que inclua os serviços de Internet, de VoIP e de IPTV denominado serviço Triple Play. O serviço Triple Play veio obrigar a revisão de toda a rede de transporte de forma a preparar a mesma para suportar este serviço de uma forma eficiente (QoS), resiliente (recuperação de falhas) e optimizado (Engenharia de tráfego). Em redes de telecomunicações, tanto a quebra de uma ligação como a congestão nas redes pode interferir nos serviços oferecidos aos consumidores finais. Mecanismos de sobrevivência são aplicados de forma a garantir a continuidade do serviço mesmo na ocorrência de uma falha. O objectivo desta dissertação é propor uma solução de uma arquitectura de rede capaz de suportar o serviço Triple Play de uma forma eficiente, resiliente e optimizada através de um encaminhamento óptimo ou quase óptimo. No âmbito deste trabalho, é realizada a análise do impacto das estratégias de encaminhamento que garantem a eficiência, sobrevivência e optimização das redes IP existentes, bem como é determinado o número limite de clientes permitido numa situação de pico de uma dada rede. Neste trabalho foram abordados os conceitos de Serviços Triple Play, Redes de Acesso, Redes Núcleo, Qualidade de Serviço, MPLS (Multi-Protocolo Label Switching), Engenharia de Tráfego e Recuperação de falhas. As conclusões obtidas das simulações efectuadas através do simulador de rede NS-2.33 (Network Simulator versão 2.33) serviram para propor a solução da arquitectura de uma rede capaz de suportar o serviço Triple Play de uma forma eficiente, resiliente e optimizada.Orientador: Paulo Nazareno Maia Sampai

Developing a mining plan for restarting the operation at Uis mine

AfriTin Mining Limited plans to reopen the Uis tin mine in Namibia and establish a pilot processing plant for phase 1 of the Uis tin project, which is scheduled to commence in the last quarter of 2018 . A mining plan is required for phase 1 to supply the new pilot processing plant with 500 kt of run-of-mine ore per annum, for a period of 5 years. New geological mapping and three-dimensional modelling of the mining area were utilized to identify the most optimal mining locations that require low initial waste stripping. An open-pit mining method was selected to target the surface outcrops of the pegmatite orebodies. The mine design criteria were determined and used as input to generate the mine design by utilizing professional engineering software. The mine design was optimized and an overall stripping ratio of 0.81 was achieved. A 5-year production schedule was developed for the mine design according to quarterly periods of three months. A fixed production target of 125 kt of ore was assigned to the quarterly periods, and a ramp-up production target of 65 kt of ore was assigned for the first period. The mobile mining equipment requirements were calculated, and recommendations were made for implementing the 5-year mining plan.Paper written on project work carried out in partial fulfilment of B.Eng (Mining Engineering) degree.http://www.saimm.co.za/journal-papersam2020Mining Engineerin

Laparoscopically-assisted vaginal hysterectomy for enlarged uterus: operative outcomes and the learning curve

Objectives: The aim of the study was to compare the effects of uterine size and surgeon experience on the surgical out­comes of laparoscopically-assisted vaginal hysterectomy (LAVH) for benign gynecological conditions. Material and methods: This was a retrospective analysis of 184 LAVH cases. All hysterectomies were performed by the same surgeon and divided into two groups, with uterine weight of < 280 g (group 1) and uterine weight of > 280 g (group 2). The groups were compared in terms of the effects of the uterine size and surgeon experience vs. the operative outcomes (operative time, change in hemoglobin levels, hospital stay, and perioperative complications). Results: No significant differences in mean age, parity, history of chronic systemic diseases and previous surgery history were observed between the two groups. However, operative time was significantly greater in group 2 as compared to group 1 (132.1 ± 42.7 minutes vs. 111.5 ± 30.4 minutes, p < 0.05). There were no differences in the hospital stay and perioperative complications between the two groups. One case of bladder injury occurred in each group and one patient underwent a second laparoscopic surgery for postoperative bleeding in group 2. Greater surgeon experience was demonstrated to be associated with decreased operative bleeding and, consequently, smaller differences between preoperative and postop­erative hemoglobin levels. Operative time was also reduced as the surgeon was getting more experienced but the effect did not reach statistical significance. Conclusions: Our study supports the thesis that LAVH is a safe and effective procedure for managing benign gynecologi­cal conditions. Despite increased operative time, LAVH can be safely performed for enlarged uterus in conjunction with increased surgeon experience

Agricultural Academy

Abstract UREMIS, I., M. E. CALISKAN, A. ULUDAG and S. CALISKAN, 2009. Weed management in earlyseason potato production in the Mediterranean conditions of Turkey. Bulg. J. Agric. Sci., Early-season potato production is a profitable system in the Mediterranean part of Turkey. Weeds are problem in early-season potato production. The effect of combinations of extended season weed control techniques (none, hand-hoeing twice, black or clear plastic mulch placed at planting, or metribuzin POST and soil applied herbicides (none, trifluralin PPI, or a commercially formulated combination of pendimethalin and metolachlor PRE) on weed control and potato yield were compared. No weed species shift was observed due to treatments. Soil applied herbicides kept weeds under pressure through growing season in some extent, improved effect of black plastic mulch on weed control, caused bigger tubers and consequently higher class-A yield. Although hand-hoeing twice during the growing season resulted in the lowest percent weed cover at harvest and better yield, cost and availability of labor may not make this method feasible for a potato grower. Combinations of PPI or PRE soil-applied herbicides and plastic mulch will be necessary. Overall, black rather than clear plastic mulch seems to be the best choice for an extended-season control method following a PPI or PRE herbicide. Metribuzin controlled weeds in some extent but the effect did not translate to potato yield. Plastic mulches, especially clear one, caused earliness at emergence, which might help earlier harvest

The association between coronary flow rate and impaired heart rate recovery in patients with metabolic syndrome: A preliminary report

Background: The aim of this study is to evaluate heart rate recovery (HRR) and association between coronary flow rate and HRR in patients with metabolic syndrome (MS) who had morphologically normal coronary angiogram.Methods: Study population included 43 patients with MS and 37 control subjects without MS. All patients were selected from individuals who had recently undergone coronary angiography in our hospital and were diagnosed as having angiographically normal coronary arteries. Exercise stress test results obtained prior to coronary angiography were evaluated for calculating HRR and other parameters. In addition, coronary flow was objectively evaluated for each major coronary artery in each subject using TIMI frame count method.Results: All HRR values calculated were detected significantly lower in MS group compared to controls (HRR first: 32 ± 9 vs. 37 ± 10; p = 0.01, second: 46 ± 11 vs. 52 ± 11; p = 0.03, third: 51 ± 12 vs. 59 ± 12; p = 0.00, fourth: 54 ± 13 vs. 61 ± 2; p = 0.02). TIMI frame counts for each major epicardial coronary artery and mean TIMI frame count were also found to be significantly higher in MS group compared to controls (left anterior descending artery:51 ± 24 vs. 39 ± 15; p = 0.009, left circumflex artery: 32 ± 11 vs. 24 ± 7; p = 0.001, right coronary artery: 33 ± 14 vs. 24 ± 10; p = 0.003, mean TIMI frame count: 38 ± 15 vs. 29 ± 9;p = 0.002). Additionally, significant negative correlations were also detected between HRR first minute and coronary TIMI frame count values in patients with MS. None of MS parameters did not affect HRR values, however mean TIMI frame count independently associated with HRR first minute (p = 0.04) in patients with MS.Conclusions: Impaired coronary blood flow occurring in MS might be a clue of autonomic dysfunction in addition to previously known endothelial dysfunction.

Resveratrol affects histone 3 lysine 27 methylation of vessels and blood biomarkers in DOCA salt-induced hypertension

Hypertension is a risk factor for the cardiovascular diseases. Although, several drugs are used to treat hypertension, the success of the antihypertensive therapy is limited. Resveratrol decreases blood pressure in animal models of hypertension. This study researched the mechanisms behind the effects of resveratrol on hypertension. Hypertension was induced by using the deoxycorticosterone acetate (DOCA)-induced (15 mg/kg twice per week, subcutaneously) salt-sensitive hypertension model of Wistar rats. Hypertension caused a decrease in endothelium-dependent relaxations of the isolated thoracic aorta. Resveratrol treatment (50 mg/l in drinking water) prevented DOCA salt-induced hypertension, but did not improve endothelial dysfunction. Plasma nitric oxide (NO), asymmetric dimethylarginine (ADMA), total antioxidant capacity (TAC) and hydrogen sulfide (H2S) levels were not changed by DOCA salt application. However, treatment of resveratrol significantly decreased ADMA and increased TAC and H2S levels. NO level in circulation was not significantly changed by resveratrol. DOCA salt application and resveratrol treatment also caused an alteration in the epigenetic modification of vessels. Staining pattern of histone 3 lysine 27 methylation (H3K27me3) in the aorta and renal artery sections was changed. These results show that preventive effect of resveratrol on DOCA salt-induced hypertension might due to its action on the production of some blood biomarkers and the epigenetic modification of vessels that would focus upon new aspect of hypertension prevention and treatment. © 2014, Springer Science+Business Media Dordrecht

Comparing the emergence of Echinochloa crus-galli populations in different locations. Part II: similarities and threshold parameters

The variability in the emergence process of different populations was confirmed for two Echinochloa crus-galli populations, one from Italy (IT) and the second from Norway (NO). Seeds were sown in 12 localities over Europe and the Middle East, and the emergence patterns of IT and NO were compared with those of several local populations at each location. Seeds of each population were sown in pots buried to the ground level. The base temperature (Tb) for emergence was estimated by (1) analysing logistic models applied to the field emergence of IT and NO, and (2) a germination assay set in winter 2020 at constant temperatures (8, 11, 14, 17, 20, 26, 29°C) with newly collected seeds in 2019 from the same fields where IT and NO had previously been harvested in 2015. The logistic models developed for IT and NO in each location showed that the emergence pattern of IT was similar to that of the local populations in Poland, Italy, Spain, Turkey South and Iran, while NO fitted better to those in Sweden and Latvia. No germination was obtained for IT in a germination chamber, but the estimated Tb with the logistic model was 11.2°C. For NO, the estimated Tb was 8.8°C in the germination chamber and 8.1°C in the field. Results suggest that adaptation to local environmental conditions has led to inter-population differences in Tb and parameter estimates of thermal-time models to predict the emergence of E. crus-galli should only be used for populations with similar climatic and habitat conditions.The authors thank all the technicians, students and institutions that have contributed to establishing and maintaining the field experiment. We also thank Dr. Frank Forcella and James Eklund, from the USDA‐ARS in Morris (MN), for providing the dataloggers and facilitating the collection of soil temperature data in each location. Our thanks also to the Spanish Ministry of Economy and Competitiveness for funding to Royo‐Esnal through the AGL2017‐83325‐C4‐2‐R; Duzce Üniversitesi, Turkey, for funding to Uludag (Project No: 2015.11.02.375); and the Norwegian Research Funding for Agriculture and the Food Industry and project partners in Research Council of Norway Project no. 267700 for supporting Tørresen in the experiment. Uludag thank his two graduate students, Miss Buyukkurt and Zambak, and Murdoch thank MSc student, Mr Guangxing Xie, who carried out some of the germination assays. Royo‐Esnal thank Jordi Izquierdo for providing the seeds of L3 population for the experiment in Lleida. Finally, the authors are also grateful to the EWRS, for providing funds to enable the working group participants to meet and discuss the collaborative experiment