DigitUMa
University of Madeira Institutional Repository
Bem-vindo ao Repositório Digital da UNIVERSIDADE DA MADEIRA.
O Repositório da Universidade da Madeira (UMa), conhecido pelo acrónimo DigitUMa, tem como objetivo a disponibilização, em regime de livre acesso e texto integral, de toda a produção científica realizada pelos docentes, investigadores da UMa, discentes dos 2º e 3º ciclos e pelos funcionários.
O Repositório Institucional, DigitUMa, assenta na política de Acesso Aberto à informação e conhecimento científicos.
Recent Submissions
Marketing interno na hotelaria: plano estratégico do caso prático do Hotel ABC
Publication . Correia, Gonçalo Duarte; Franco, Mara José Sousa; Almeida, Nuno Miguel Castanheira
Este relatório investiga o impacto do Marketing Interno (MI) na gestão estratégica no setor
da hotelaria. O estudo tem como objetivo analisar as práticas de MI do hotel e seu efeito na
satisfação dos colaboradores e na qualidade do serviço, utilizando métodos qualitativos
como observação direta e questionários. A revisão de literatura destaca a importância do
turismo na economia e a necessidade de Marketing eficaz. O MI, em particular, valoriza os
colaboradores, criando um ambiente de trabalho positivo que melhora a qualidade do
serviço. Elementos-chave do MI incluem formação contínua, comunicação eficaz,
desenvolvimento de carreira e sistemas de recompensa. A análise inclui uma avaliação
SWOT das práticas de MI do hotel, identificando pontos fortes como lealdade dos clientes e
estabilidade da equipe, e pontos fracos como a localização remota. As oportunidades
incluem o apelo turístico da região, enquanto as ameaças envolvem alta concorrência e
instabilidade económica. Desenvolver um plano eficaz de MI envolve analisar a situação
interna, definir objetivos SMART, identificar stakeholders, e implementar e avaliar
estratégias. O plano visa melhorar a comunicação interna, aumentar a motivação e garantir
um ambiente de trabalho positivo, resultando em alta qualidade de serviço e satisfação do
cliente. Os resultados indicam o papel crucial da comunicação interna nas estratégias de MI.
Formação contínua e desenvolvimento profissional são vitais para manter a moral e a
motivação da equipa. Práticas eficazes de MI melhoram significativamente a satisfação dos
colaboradores, impactando positivamente a experiência dos clientes e a reputação do hotel.
Em conclusão, o MI é essencial para a gestão estratégica na hotelaria, influenciando
diretamente a qualidade do serviço e a satisfação do cliente. Os gestores devem investir
continuamente em estratégias de MI, adaptando-se às necessidades dos colaboradores e às
mudanças externas.
Effect of nickel on the mechanical properties of spray-formed Al-15Si-2Cu alloy at elevated temperatures
Publication . Goudar, Dayanand M.; Alavandi, Mehabubsubahani R.; Bhat, Subraya Krishna; Bommenahalli, Raghukumar; Kurahatti, Rajashekar V.; Pinto, Deesy G.; Raju, K.; Pinto, Deesy
at different temperatures was examined and evaluated with that of the as-cast (AC) alloy. The microstructure of
SF alloys revealed uniformly distributed spherical shaped primary silicon and eutectic silicon phases along with
fine Ni and Cu intermetallic particles dispersed throughout the equiaxed Al matrix. The microstructure of AC
alloys consisted of coarse primary Si, flake-type eutectic phase, Cu-rich intermetallics with a complex branched
morphology and a network of short strips. The mechanical properties of the alloys were assessed at temperatures
of 30◦C, 100◦C, 200◦C and 300◦C. The SF alloys exhibited higher hardness than AC alloys at all temperatures
with a maximum increase of 74 % at 30◦C. The hardness of alloys showed a decreasing trend with increasing
temperature. The mechanical strength of SF alloys was higher than that of the AC alloys across the entire
temperature range from 30◦C to 300◦C with a decrease in ultimate tensile strength (UTS) by 4–6 % at 250◦C. The
SF alloys demonstrated a significant increase in UTS (25 % at 30◦C and 40 % at 300◦C) compared to the AC
alloys. The Al-15Si-2Cu-2Ni alloy showed highest increase (14.3–18.6 %) and Al-15Si-2Cu-6Ni alloy showed the
lowest increase (10.5 % to 14 %) in percent elongation between 30◦C and 300◦C.
Enhancing the interfacial adhesion and mechanical strength of pultruded ECR–glass fiber composites with nanofiller-infused epoxy resin
Publication . Chandra, Poorna; Venkatarayappa, Ravikumar; Chandrashekar, Savitha D.; Raveendra, Kiran; Bhaskararao, Asha P.; Bheemappa, Suresha; Goudar, Dayanand M.; Kurhatti, Rajashekhar V.; Raju, K.; Pinto, Deesy G.; Pinto, Deesy
The effect of the interaction between silica (nS) and hydroxyapatite (nHap) nanomaterials on the characteristics of unidirectional glass-fiber-reinforced epoxy (GF/Ep) composite systems is investigated in this work. The goal of the study is to use these nanofillers to improve the microstructure and mechanical characteristics. Pultrusion was used to produce hybrid nanocomposites while keeping the GF loading at a consistent 75% by weight. The hybrid nanocomposites were made with a total filler loading of 6 wt.%, including nHap, and a nS loading ranging from 2 to 4 wt.%. The mechanical performance of the composite was greatly improved by the use of these nanofillers. Compared to neat GF/Ep, hybrid nanocomposites with 6 wt.% combined fillers exhibited increased hardness (14%), tensile strength (25%), interlaminar shear strength (21.3%), and flexural strength (33%). These improvements are attributed to efficient filler dispersion, enhanced fiber-matrix adhesion, and crack propagation resistance. Incorporating 4 wt.% nS alone improved hardness (6%), tensile strength (9%), tensile modulus (21%), interlaminar shear strength (11.4%), flexural strength (12%), and flexural modulus (14%). FTIR analysis indicated Si-O-Si network formation and increased hydrogen bonding, supporting enhanced interfacial interactions. Ultraviolet reflectance measurements showed increased UV reflectivity with nS, especially in hybrid systems, due to synergistic effects. Impact strength also improved, with a notable 11.6% increase observed in the hybrid nanocomposite. Scanning and transmission electron microscopy confirmed that the nanofillers act as secondary reinforcements within the matrix. These hybrid nanocomposites present a promising material choice for various industries, including marine structural applications and automotive components.
Effect of cenosphere fillers on mechanical strength and abrasive wear resistance of carbon–glass polyester composites
Publication . Pulikeshi, K. H.; Goudar, Dayanand M.; Kurahatti, R. V.; Pinto, Deesy G.; Pinto, Deesy
Fabric-reinforced hybrid polymer composites are present in almost every sector of modern life, and most essential areas of research in recent years have focused on glass–carbon fabric with filler material composites. Fabric and fillers are employed in strengthening polymer composites with the aim of improving their mechanical and tribological properties. The primary objective of this investigation was to investigate thetribological and mechanical properties of unfilled and cenosphere-filled carbon–glass-reinforced polyester composite systems, utilizing two types of fabric (glass and carbon) with cenosphere filler in varying weight fractions (0, 2.5, 5, 7.5, 10, and 12.5 wt.%) for both carbon fabric and the cenosphere. The abrasive wear characteristics were evaluated using a stainlesssteel wheel abrasion tester, utilizing silica sand as the abrasive material. Tests were performed at various distances (360–1800 m) and loads (12 N and 24 N). The results show that the wear rate of carbon–glass fabric-reinforced polyester composites differs significantly, with and without cenosphere fillers. Notably, the unfilled composites exhibit the highest wear volume loss, indicating a substantial improvement in wear resistance with the addition of cenospheres. The results reveal that in carbon–glass fabric-reinforced polyester composites, specific wear rate decreases when more cenospheres are loaded. The wear rate was successfully reduced by cenospheresunder silica sand as an abrasive. Compared to unfilled composites, the mechanical properties of filled composites exhibit superior performance. These variations were explained by examining the worn-out surfaces under an SEM and correlating the features observed with the mechanical properties.
Effect of sintering temperature on the physical and mechanical characteristics of fabricated ZrO2–Cr–Ni–Ce–Y composite
Publication . Saini, Brajesh Chandra; Jain, Naman; Rao, Dinesh Kumar; Singhal, Varun; Verma, Akarsh; Goudar, Dayanand M.; Raju, Kandavalli; Pinto, Deesy G.; Pinto, Deesy
The present study investigates the synthesis and characterization of a zirconium oxide (ZrO2)-based metal composite doped with cerium (Ce) and yttrium (Y), using chromium (Cr) and nickel (Ni) as base metals. These constituents were selected for their superior mechanical properties and compatibility with the ceramic phase. High-purity powders were homogenized via high-energy ball milling, followed by cold pressing and sintering in a controlled atmosphere of hydrogen. The sintering process was conducted at temperatures ranging from 850 °C to 1350 °C to examine the evolution of microstructure, grain growth, and densification. Scanning electron microscopy (SEM) revealed a homogeneous distribution of phases, with distinct microstructural features attributed to each element at different sintering temperatures. The experimental results revealed that the composite’s density was increased by 30% and porosity was reduced by 61% at a sintering temperature of 1350 °C. The hardness and flexural strength of composite were found to be 23% and 60% higher at 1350 °C, respectively, compared to that at 850 °C, suggesting enhanced mechanical properties due to cerium and yttrium reinforcement within matrix and efficient doping and phase transformation. Overall, incorporation of cerium and yttrium significantly improved mechanical behavior and phase stability of ZrO2–Cr–Ni composite, highlighting its potential for advanced engineering applications.