Developing new chemical–rheological models and chemical–durability indices of bitumen

Significant correlation among chemical properties, rheological characteristics and durability of bitumen is very important in evaluating and modifying bitumen. However, a number of previous studies found inconsistent correlation. Therefore, a study on developing new chemical-rheological models and chemical-durability indices was carried out. Two bitumen fractionation method, Rostler and Corbett methods were used to extract each chemical fraction of bitumen. A number of experiments were conducted to evaluate the effect of each chemical fraction on bitumen rheology such as the effect of asphaltenes, polar aromatics, naphthene aromatics, nitrogen bases, first acidaffins, second acidaffins and paraffins on elastic modulus (G’), viscous modulus (G”) or fatigue factor (G*sin[δ]), and rutting fator (G*/sin[δ]). Two bitumen from different sources, namely Petronas petroleum bitumen and Buton rock asphalt (BRA) bitumen, were used. New chemical�rheological models were formulated to estimate the bitumen rheology in corporating parameters which are G’, G” or (G*sin[δ]), and (G*/sin[δ]) based on the chemical properties. Furthermore, new chemical durability indices that may indicate the ageing rate of bitumen during short-term and long-term ageing were also formulated. Based on statistical analyses, the models and the indices, which were developed by using chemical properties according to Rostler method were found to be invalid because the real and the predicted rheology were significantly different. While according to Corbett method the models and the indices were valid because the differences is not significant since t-score of the models and the indices were maximum 2.679 and 2.119 or less than t-critical 2.797 and 2.861 respectively). The novelties of this study are the new models and the new indices can be used to predict the bitumen rheology and ageing rate based on the chemical composition. Furthermore, they are very important as guides in modifying a bitumen chemical composition to produce a bitumen mixture with the desired rheology and short-term or long-term ageing rat

Optimizing Service Differentiation Scheme with Sized-based Queue Management in DiffServ Networks

In this paper we introduced Modified Sized-based Queue Management as a dropping scheme that aims to fairly prioritize and allocate more service to VoIP traffic over bulk data like FTP as the former one usually has small packet size with less impact to the network congestion. In the same time, we want to guarantee that this prioritization is fair enough for both traffic types. On the other hand we study the total link delay over the congestive link with the attempt to alleviate this congestion as much as possible at the by function of early congestion notification. Our M-SQM scheme has been evaluated with NS2 experiments to measure the packets received from both and total link-delay for different traffic. The performance evaluation results of M-SQM have been validated and graphically compared with the performance of other three legacy AQMs (RED, RIO, and PI). It is depicted that our M-SQM outperformed these AQMs in providing QoS level of service differentiation.Comment: 10 pages, 9 figures, 1 table, Submitted to Journal of Telecommunication

Boosting traditional management of Sahelian Faidherbia parks

Traits and functions of Apple?ring acacia (Faidherbia albida (Del.) Chev.), iconic species of sahelian agroforesters, are well known of agro?pastoralists farmers and scientists. Traits include its deep taproot system reaching the water table on alluvial soils, its inverted phenology, and the leaves being present in the dry season and absent during the rainy season, and its ability to vegetative propagation (root suckers, coppices of stumps and branches). For functions, its general positive impact on associated crop, production of forage (leaves and fruit) and firewood are also widely recognized. However, the area extension of Faidherbia agroforestry systems (parklands) is still far below what it could be, despite the isolated actions of many extension services and NGOs. The example of northern Cameroon shows that research on crop productivity under Faidherbia helped changing the perception of this tree by services and operators of agricultural development, in the 1990s. Then it was possible to "boost" the restoration of these parklands on a large scale, mobilizing public funding, associations and farmer organizations and subsidizing (even at a low level) Assisted Natural Regeneration. The results of socio?economic surveys and pruning trials, conducted in 2012, confirm, at least, the interest of farmers for pruning the trees and fire?wood sustainable productivity of this method. Demand of farmers, on the right of pruning trees and freely use the wood harvested has been taken into account in the draft amendment to the Law on the forest regime, introduced in 2012, to the Cameroon parliament. These studies on Faidherbia albida have helped Cameroonian farmers to keep more than one million young trees, but also have helped to change the law in the sense of increasing the rights of peasants on the tree. This concern planted trees, often exotic, but also natural species kept and maintained by farmers, such as shea?butter tree (Vitellaria paradoxa) and many other multipurpose species. (Texte intégral

Neuronal in vitro impact of Amblyommaamericanumsalivary glands extracts

When a tick feeds off a host, the salivary glands of the tick excrete saliva to assist the tick in feeding (1). The reason saliva assists the tick in consuming its blood meal is due to its immunosuppressive, anti-inflammatory, and anti-coagulant properties (2).Tick salivary glands also play an important role in the transmission of tick-borne pathogens (3). We wanted to investigate the effect of tick salivary gland extracts (SGE) on human neurons. For our experiment, the organism whose salivary gland extract we used was the Amblyomma americanum. We compared the effects of salivary gland extract from ticks collected in the field and ticks reared in a lab colony. Our results showed that the salivary gland extract from the two types of ticks affected the neurons differently, and the salivary gland extract of the field tick was more damaging to the neurons. This indicates that SGE from field ticks, together with infectious agents, could result in a more severe neuronal impairment in a human host than the infectious agent alone

Influence of Critical Soft Factors on Quality Improvement and Organizational Performance

This study was to determine the relationships of selected variables, namely management commitment, customer focus, employee involvement, training and education, reward and recognition and supplier relationship in predicting quality improvement (QI) and their relationships to organizational performance (OP). The survey research provided a method of empirical verification utilizing stratified and simple random sampling to determine the relationships between variables at the time of study. The sample consisted of 255 firms from the electrical and electronics sector. The selection of respondents involves a complete list of electrical and electronics firms within West Malaysia which was obtained from directory list Federation of Malaysian Manufacturers- Malaysian External Trade Development Corporation (FMM-MATRADE). The quantitative data were subjected to various descriptive-correlation statistical analyses, multiple regression, mediation analyses, and structural equation modeling. In this study, the findings support the relationship between the independent variables and QI. Five variables, namely management commitment, customer focus, employee involvement, training and education, and reward and recognition explained 93.8% (F = 748.342, p = 0.0001) of QI. Only four variables, namely management commitment, customer focus, employee involvement, and reward and recognition significant predictors of organizational performance, and collectively these variables explained 25.6% (F = 15.636, p = 0.0001) of the variation in OP. QI is a significant predictor in determining OP. The effect of the QI as a mediator between all the exogenous variables and OP is found. Reward and recognition exerts the strongest total effect (0.688) on OP whereas customer focus emerged as having the second strongest total effect (0.588) on OP. The implications as well as the limitations of the study were discussed in detail. Future research suggestions were advocated, in particular, the replication of this study to other industry. Further work is also needed to develop a new model and identify the relationship between the critical soft and hard factors and their joint contribution to QI and OP. The implications as well as the limitations of the study were discussed

PELATIHAN KETRAMPILAN KERAJINAN KRIA SEBAGAI UPAYA PENANAMAN JIWA KEWIRAUSAHAAN DI SANTRI PONDOK PESANTREN Al AMIN PALUR MOJOLABAN SUKOHARJO

Pengabdian Kepada Masyarakat oleh Tim ISI Surakarta tahun 2014 bertujuan melakukan pelatihan dan pendampingan pembuatan produk kria. Pengabdian dilaksanakan di SMA Pondok Pesantren Al Amin Palur Mojolaban Kabupaten Sukoharjo. Metode pelaksanaan menerapkan pendekatan partisipasi dan kolaborasi mitra, baik dalam hal pengumpulan data, pendampingan pembuatan produk sampai dengan pasca pelatihan. Penerapan metode partisipasi dan kolaborasi mitra diharapkan dapat mengimplementasikan kolaborasi yang sesungguhnya, mitra dapat berpartisipasi dan berkolaborasi sesuai dengan kapasitasnya, serta dapat berkontribusi secara maksimal sehingga tim pengabdi dapat melatih dan mendampingi sesuai dengan kebutuhan yang ada di lapangan. Hasil kegiatan berupa beberapa karya asesoris interior berupa lukisan kanvas ABSTRAK. dengan objek tumbuh-tumbuhan. Terdapat keterbatasan tentang objek untuk membuat asesoris interior, Siswa cenderung tidak mau mengambil objek hewan atau manusia. Kegiatan pendampingan melukis merupakan permintaan dari ustad Hartono da guru kesinian yang dipandang selama ini kegiatan meukis belum pernah diberikan sementara tetan ketrampilan pernah diberikan namun belum maksimal. Selama dua bulan ada progress dapat dilihat pada hasil meluis pada kertas dan selanjutnya di tuangkan secara hita putih di di kanvas dan akhirnya menjadi sebuah lukisan. Pemahaman tentang kewirausahaan diberikan secara teoritis

Job satisfaction of secondary school teachers in Tawau, Sabah

In order for the teachers to function effectively in a school system, it is important that teachers need to seek satisfaction and happiness not only in the intrinsic aspects of teaching job but also in other dimensions related to the teacher work experience in the wider social environment. This paper examines the level and differences in the job satisfaction of 200 Sabah secondary school teachers with respect to the various teachers characteristics identified as gender, service category, job title, tenure and place of origin. Data was collected through survey questionnaire. The finding reveals that secondary school teachers in Tawau, Sabah are generally satisfied with their job. There is significant relationship between job satisfaction and gender, whereby the male teachers are generally more satisfied than female teachers. The graduate teachers are more satisfied than non-graduate teachers. The higher ranking teachers are more satisfied than the ordinary teachers. Also, older teachers are more satisfied than younger teachers. However, there is no significant relationship between places of origin of teachers with job satisfaction. Based on the findings, several recommendations are proposed