Analysis of Nonviscous Oscillators Based on the Damping Model Perturbation

[EN] A novel numerical approach to compute the eigenvalues of linear viscoelastic oscillators is developed.The dissipative forces of these systems are characterized by convolution integrals with kernel functions, which in turn contain a set of damping parameters. The free-motion characteristic equation defines implicitly the eigenvalues as functions of such parameters. After choosing one of them as independent variable, the key idea of the current paper is to obtain a differential equation whose solution can be considered, under certain conditions, a good approximation. The method is validated with several numerical examples related to damping models based on exponential kernels, on fractional derivatives, and on the well-known viscous model. Taylor series expansions up to the second order are obtained and in addition analytical solutions for the viscous model are achieved. The numerical results are very close to the exact ones for light and medium levels of damping and also very good for high levels if the chosen parameter is close to initial values that are defined for every caseLázaro, M.; Casanova, CF.; Ferrer Ballester, I.; Martín Concepcion, PE. (2016). Analysis of Nonviscous Oscillators Based on the Damping Model Perturbation. Shock and Vibration. 2016:1-19. doi:10.1155/2016/9634103S119201

Socio-economic impact of cluster marketing: The case of Ned Landcare Association sweet pepper cluster

Through clustering, opportunities exist for smallholder farmers to organize their output and to sell directly to institutional markets. This paper analyses the experiences of the cluster marketing approach in Barangay Ned, Lake Sebu, South Cotabato. The case demonstrates how farmers in the cluster group developed an enterprise plan, established linkages with a microfinance institution and negotiated sales to downstream market intermediaries. Farmers in the cluster increased their technical and marketing knowledge, improved their farming and marketing practices, improved their access to capital and increased their income. Trust, confidence, commitment and unity among cluster members were established through the cluster marketing approach

Fe speciation in Iron modified natural zeolites as sustainable environmental catalysts

Natural purified mordenite from Palmarito de Cauto (ZP) deposit, Cuba, was subjected to a hydrothermal ion exchange process in acid medium with Fe2+ or Fe3+ salts (Fe2+ZP and Fe3+ZP). The set of samples was characterized regarding their textural properties, morphology, and crystallinity, and tested in the NO reduction with CO/C3H6. Infrared spectroscopy coupled with NO as a probe molecule was used to give a qualitative description of the Fe species’ nature and distribution. The exchange process caused an increase in the iron loading of the samples and a redistribution, resulting in more dispersed Fe2+ and Fe3+ species. When contacted with the NO probe, Fe2+ZP showed the highest intensity of nitrosyl bands, assigned to NO adducts on isolated/highly dispersed Fe2+/Fe3+ extra-framework sites and FexOy clusters. This sample is also characterized by the highest NO sorption capacity and activity in NO reduction. Fe3+ZP showed a higher intensity of nitrosonium (NO+) species, without a correlation to NO storage and conversion, pointing to the reactivity of small FexOy aggregates in providing oxygen atoms for the NO to NO+ reaction. The same sites are proposed to be responsible for the higher production of CO2 observed on this sample, and thus to be detrimental to the activity in NO SCR

Combining x-ray real and reciprocal space mapping techniques to explore the epitaxial growth of semiconductors

In the present work, the importance of determining the strain states of semiconductor compounds with high accuracy is demonstrated. For the matter in question, new software titled LAPAs, the acronym for LAttice PArameters is presented. The lattice parameters as well as the chemical composition of Al1-xInxN and Ge1-xSnx compounds grown on top of GaN- and Ge-buffered c-Al2O3 and (001) oriented Si substrates, respectively, are calculated via the real space Bond's method. The uncertainties in the lattice parameters and composition are derived, compared and discussed with the ones found via x-ray diffraction reciprocal space mapping. Broad peaks lead to increased centroid uncertainty and are found to constitute up to 99% of the total uncertainty in the lattice parameters. Refraction correction is included in the calculations and found to have an impact of 0.001 angstrom in the lattice parameters of both hexagonal and cubic crystallographic systems and below 0.01% in the quantification of the InN and Sn contents. Although the relaxation degrees of the nitride and tin compounds agree perfectly between the real and reciprocal-spaces methods, the uncertainty in the latter is found to be ten times higher. The impact of the findings may be substantial for the development of applications and devices as the intervals found for the lattice match the condition of Al1-xInxN grown on GaN templates vary between similar to 1.8% (0.1675-0.1859) and 0.04% (0.1708-0.1712) if derived via the real- and reciprocal spaces methods.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Plurianual Strategic Funding UID/FIS/50010/2019. FO acknowledges the FCT PhD Grant and thanks the Institut fuer Halbleitertechnik, Universitaet Stuttgart for hospitality. The authors acknowledge Professor I Watson and Professor F Schulze from the Universities of Strathclyde, Scotland, United Kingdom, and Stuttgart, Germany for the growth of the nitrides and tin compounds, respectively

Real-world outcomes of sipuleucel-T treatment in PROCEED, a prospective registry of men with metastatic castration-resistant prostate cancer.

BackgroundThe large registry, PROVENGE Registry for the Observation, Collection, and Evaluation of Experience Data (PROCEED)(NCT01306890), evaluated sipuleucel-T immunotherapy for asymptomatic/minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC).MethodsPROCEED enrolled patients with mCRPC receiving 3 biweekly sipuleucel-T infusions. Assessments included overall survival (OS), serious adverse events (SAEs), cerebrovascular events (CVEs), and anticancer interventions (ACIs). Follow-up was for ≥3 years or until death or study withdrawal.ResultsIn 2011-2017, 1976 patients were followed for 46.6 months (median). The median age was 72 years, and the baseline median prostate-specific antigen level was 15.0 ng/mL; 86.7% were white, and 11.6% were African American. Among the patients, 1902 had 1 or more sipuleucel-T infusions. The median OS was 30.7 months (95% confidence interval [CI], 28.6-32.2 months). Known prognostic factors were independently associated with OS in a multivariable analysis. Among the 1255 patients who died, 964 (76.8%) died of prostate cancer (PC) progression. The median time from the first infusion to PC death was 42.7 months (95% CI, 39.4-46.2 months). The incidence of sipuleucel-T-related SAEs was 3.9%. The incidence of CVEs was 2.8%, and the rate per 100 person-years was 1.2 (95% CI, 0.9-1.6). The CVE incidence among 11,972 patients with mCRPC from the Surveillance, Epidemiology, and End Results-Medicare database was 2.8%; the rate per 100 person-years was 1.5 (95% CI, 1.4-1.7). One or more ACIs (abiraterone, enzalutamide, docetaxel, cabazitaxel, or radium 223) were received by 77.1% of the patients after sipuleucel-T; 32.5% and 17.4% of the patients experienced 1- and 2-year treatment-free intervals, respectively.ConclusionsPROCEED provides contemporary survival data for sipuleucel-T-treated men in a real-world setting of new life-prolonging agents, which will be useful in discussing treatment options with patients and in powering future trials with sipuleucel-T. The safety and tolerability of sipuleucel-T in PROCEED were consistent with previous findings

A road to nowhere? The non-transitional sequence at El Esquilleu (Cantabria, Spain)

El Esquilleu cave has one of the most complete Middle Paleolithic stratigraphies of northern Iberia with a complete chronological framework almost continuous from the beginning of MIS3. The complete analysis of the materials including the last section of the sequence corresponding to the last chronological interval of the occupation in the region shows clear evolutionary tendencies by important changes in the composition of the lithic assemblage. Its study confirms a continuous occupation without any gaps during the Mousterian until recent dates but without any Upper Paleolithic presence. This sequence, referenced to the Mousterian settlement of the Picos de Europa mountains, testifies to the existence of a Mousterian presence in northern Iberia with no clear relation to other Cantabrian areas. Consequently, its occupation without a break until the crucial phase of the end of the Middle Paleolithic suggests a non-transitional process in the history of local Neanderthal groups

Impact of Collaborative Marketing on Vegetable Production Systems: the Case of Clustering in the Southern Philippines

In the Southern Philippines, the clustering method has been introduced to smallholder vegetable farmers as a development approach to facilitate linkages with markets, while simultaneously assisting farmers to establish more organized and effective groups. For the clusters to sustain their linkages with buyers, they must often adapt their production systems to meet the buyers’ requirements. This study explores the impact of cluster marketing on vegetable production systems in the Southern Philippines. Key changes in the production systems include the use of superior varieties to increase the marketable yield and to mitigate disease, the introduction of protected cropping through rain shelters to minimize losses from adverse climatic conditions, and the application of non-chemical inputs to reduce production costs

Impacts of clustering of vegetable farmers in the Philippines

This assessment was made as part of a systematic process of evaluating the impacts of clustering vegetable farmers in the southern Philippines. Program theory was used to map the impacts. The performance of cluster and non-cluster farmers was compared. Farmers’ performance before and after clustering was also examined. The study found that, on average, cluster farmers had higher incomes than non-cluster farmers. Moreover, farmers increased their income by about 47% after clustering. Examining the returns on investment in the research project, it was found that the net present value (NPV) was 35.3 million pesos, the internal rate of return (IRR) 48.6% and the benefit:cost ratio (BCR) 2.47. When spillover effects were considered at a 5% adoption rate, the NPV, IRR and BCR increased to 106.9 million pesos, 81.5% and 3.8, respectively

Experiences with the Catholic Relief Services' clustering process for agroenterprise development and some suggestions for improvement

An evaluation of the Catholic Relief Services’ (CRS) eight-step clustering approach to agroenterprise development was a key focus of the Australian Centre for International Agricultural Research (ACIAR) – Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development (PCAARRD) horticulture project on ‘Enhancing the profitability of selected vegetable value chains in the southern Philippines’. The CRS approach encourages farmers to form small, collaborative marketing groups (clusters) and to facilitate the sustainable development of these clusters. The research, which used participative action learning and action research processes, identified that an enhanced clustering approach should incorporate processes that overcome issues such as: input financing arrangements to replace loans from informal moneylenders and traders; risks associated with production failures and pest and disease problems; maintaining relationships with buyers; and building group resilience and independence so that donor agencies have an exit strategy. The research findings suggest that to enhance the sustainability of the clusters the CRS eight-step process should be applied to three phases: (i) establishment, (ii) building resilience and (iii) implementing an exit strategy

Marketing Benefits Derived from Clustering: the Case of Vegetable Clusters in Mindanao

One of the most limiting constraints for improving the profitability of smallholder vegetable farmers is poor marketing. With the lack of knowledge and inability to negotiate with downstream buyers, farmers have little option other than to sell their products to the traditional market. To facilitate access to technical information, credit and institutional markets, smallholder farmers are forming collaborative marketing groups. Clustering is one form of collaborative marketing in which smallholder farmers are organized into small groups within a defined territory or geographic area. Using the CRS Eight Step Plan for Agro-enterprise Development, 29 clusters were formed in three provinces in the Southern Philippines. This study explores the various marketing benefits smallholder farmers have achieved after joining the cluster. After interviewing 61 vegetable farmers from 10 clusters using a structured questionnaire, results show that upon joining the cluster, farmers became more aware of their buyer’s preference for product quality and gained knowledge on how to properly handle and package their produce. Cluster farmers increased their income from vegetable farming by selling a greater product variety, a larger volume and gaining access to high value markets