We are going through a period in which the concept of the smart village (SV) is a novelty for the... more We are going through a period in which the concept of the smart village (SV) is a novelty for the management of a community, and the new smart economy of the village is based on the power of community support. Appropriately, the development of a SV is related to a family’s participation in the motivation and access to education, the increase in knowledge of information technology, information and communications technology (ICT) literacy, and also in the creation of facilities for research and development (R&D). The partnership between the public administration, the private sector, and the community heads will lead to a smart economy within the village. At the same time, the intervention of the food system to support climate change can be supported by intelligent agriculture. The SV has a strong social significance; research in the field can be multidisciplinary, including human nutrition, climate change, and community education. This paper aims to X-ray the research areas of the SV ...
This paper presents a fuzzy quality certification of wheat. This analysis is based on the fuzzy a... more This paper presents a fuzzy quality certification of wheat. This analysis is based on the fuzzy analysis model of wheat. We developed a Matlab application with the help of which we modeled the perceptions in relation to the main quality physical and chemical characteristics of wheat obtaining a quality index of wheat lots. The algorithm presented in this article allows for obtaining and using the global quality index, generating applicability not only to the commercial sphere as a quality reference and price setting, but also a measure of appreciation of processing opportunities. Indices of fuzzy quality associated with wheat lots using a fuzzy model offer the opportunity to develop local markets through quality certification.
Lignocelluloses residues from the post-harvest crop are receiving great scientific attention nowa... more Lignocelluloses residues from the post-harvest crop are receiving great scientific attention nowadays. Generally, the composite materials based on lignocelluloses waste present low density and weight, and better insulation properties compared with those petroleum-based. This study presents the results of experimental investigations regarding soundproofing capabilities for a composite material based on expanded perlite (EP) and natural polymers matrix (starch) reinforced with rapeseed stalks waste. The preparation of light-weight samples of composites was performed at room temperature through a mechanical mixing process of EP with starch polymers and rapeseed residues until optimum moisture content composition was obtained. Rapeseed stalks long fibers were avoided through the preliminary dry grinding procedure, and the composite was air-dried at room temperature for 48 h. Four samples of composites with different ratio of EP and rapeseed waste were considered. The evaluation of sampl...
Membrane processes are a way to remove unwanted elements from wastewater stream. The permeability... more Membrane processes are a way to remove unwanted elements from wastewater stream. The permeability is an important parameter to filter wastewater and membrane fouling is of great interest in membrane filtration because reduce wastewater flow through the membrane. In order to improve the filtration process, many studies have investigated the use of nanoparticles added in the polymeric membranes and how much influence the permeation properties of membranes. A variety of nanoparticles have been used to modify polymer membranes, such as Al2O3, SiO2, TiO2, ZrO2, Fe3O4, Ag. Nanoparticles are used to improve the properties of membranes like hydrophilicity, permeability and fouling resistance. This paper shows the influence of the TiO2 nanoparticles with a concentration of 0.125 wt.%, on the permeation properties and dyes rejection of the PES and PSf membranes and makes a comparison with the results obtained by other authors.
This study deals with vibratory equipments dynamic behaviour and especially reveals some critical... more This study deals with vibratory equipments dynamic behaviour and especially reveals some critical aspects regarding the flexible coupling within and those influences on entire system evolution. Changing of dynamic characteristics, additional dynamic loadings and variances reducing of vibration parameters frame the main hypothesis of the research. This paper briefly presents a few theoretical assessments in terms of linear and nonlinear approaches of driving chain elements. Realistic expanded, also computational simplified models have been provided. Simulated behaviors denote that many of the reported observation regarding the serviceable dynamic distortions are correctly, and impose a set of additional instrumental tests in order to obtain a good accuracy for mathematical models.
One of the most important problem of the operating machines is the accidental failures. These fai... more One of the most important problem of the operating machines is the accidental failures. These failures generates stoppages that disturb the technological flow by introducing delays. The present paper proposes a method to control the working without failure for any equipment or machine. More exactly, each element is designed with an imposed lifespan between maintenance interventions. In these conditions, it is possible to plan precise maintenance intervention stoppages, known beforehand and with minimum stoppage time. In order to achieve these objectives, there are several stages, namely: - Identification and design of all parts, functional role as well as lifespan; - Analyzing lifespan information and setting the optimal operating time for each piece to ensure a minimum number of stoppages to restore working parameters; Re-designing the parts (where applicable) in order to change the lifespan as previously defined. This operation will involve changes in shape or material, with immed...
The use of the finite element method for dynamic analysis of multicorp systems with elastic eleme... more The use of the finite element method for dynamic analysis of multicorp systems with elastic elements implies the solving of numerous problems related to the computational techniques and the particularity of such a study in comparison with the techniques applied to the classic finite elements For such systems, special features arise from the non-linearity of the matrix coefficients appearing in the differential equation system that describe the mechanical system response and the occurrence of additional terms within these equations. In the paper a comparison is made between the finite element results of the modal response considering the third degree polynomial shape functions and the fifth degree polynomial shape functions. It is also analyzed how the number of finite elements considered for the analysis of a beam can influence the obtained results.
The paper presents a new kind of one piece compensatory coupling which function principle puts it... more The paper presents a new kind of one piece compensatory coupling which function principle puts it out from all the known categories. It is also presented the static forces state in the active zone of the coupling. In order to get the up mentioned aim, it is used the finite element programme (F.E.P.), which determines the characteristic dimensions of the coupling too.
This work presents a practical solution intended for dynamic diagnosis of the technical systems b... more This work presents a practical solution intended for dynamic diagnosis of the technical systems based on a set of computational methods for processing and analyzing of the acquired signals. This ensemble of methods leads to the joint time-frequency evaluations and assures a multiple way to estimate the potential damages of certain parts of the tested system. Short-Time-Fourier-Transformation, Cepstrum analysis, power spectral density estimate, together with a group of stochastic estimators composes the structured procedure for dynamic diagnosis. The proposed approach of dynamic diagnosis combines the advantages of the time domain analysis, such as the simplicity and the possibility of parameters investigation during their time evolution, with the power of spectral complex evaluations, sustained by the distribution and shifting trend of spectrum. Hereby it has provided a suitable tool for characterization of spectral composition changes in time during the entire experimental tests. T...
This study deals with the problematic of vibratory equipments driving system taking into account ... more This study deals with the problematic of vibratory equipments driving system taking into account both the requirements of functional performances related to the final technological quality, and the dynamic phenomenon appears during the working cycle according to the transmission way from the energy source to the vibration generator. This analysis provides useful assessments for equipment design no matter the technological machine type. Hereby this study tries to dignify the dynamic state deviations induced by the components characteristics of the driven equipment, and to reveal the means for minimizing the parameters variances.
... Luiza DASCHIEVICI, Daniela GHELASE, Cristian SIMIONESCU University Dunarea de Jos of Galati... more ... Luiza DASCHIEVICI, Daniela GHELASE, Cristian SIMIONESCU University Dunarea de Jos of Galati, Faculty of Engineeering Braila email: daniela.ghelase@ugal.ro ... The first known documented experimental researches were made by Leonardo da Vinci, probably in 1500. ...
Abstract: The paper contains an appreciation regarding the actual stage of knowledge in metal cut... more Abstract: The paper contains an appreciation regarding the actual stage of knowledge in metal cutting field from the viewpoint of tribologic aspects and defines main aspects related to cutting factors influencing tools wearing and lastingness. The paper shows a proposal of ...
One of the reasons causing vibration for gear hob toothing is the shock at the tool’s entry, whic... more One of the reasons causing vibration for gear hob toothing is the shock at the tool’s entry, which is generated by the great length of the cutting edge entering the metal at the same time. This paper proposes a fragmentation of the cutting edge so that its length is much smaller. Moreover, the cutting scheme is also changed, so that the entire tooth line of the piece is made with four consecutive teeth of the tool. Therefore, the impact force input generating shock and vibration is significantly reduced.
We are going through a period in which the concept of the smart village (SV) is a novelty for the... more We are going through a period in which the concept of the smart village (SV) is a novelty for the management of a community, and the new smart economy of the village is based on the power of community support. Appropriately, the development of a SV is related to a family’s participation in the motivation and access to education, the increase in knowledge of information technology, information and communications technology (ICT) literacy, and also in the creation of facilities for research and development (R&D). The partnership between the public administration, the private sector, and the community heads will lead to a smart economy within the village. At the same time, the intervention of the food system to support climate change can be supported by intelligent agriculture. The SV has a strong social significance; research in the field can be multidisciplinary, including human nutrition, climate change, and community education. This paper aims to X-ray the research areas of the SV ...
This paper presents a fuzzy quality certification of wheat. This analysis is based on the fuzzy a... more This paper presents a fuzzy quality certification of wheat. This analysis is based on the fuzzy analysis model of wheat. We developed a Matlab application with the help of which we modeled the perceptions in relation to the main quality physical and chemical characteristics of wheat obtaining a quality index of wheat lots. The algorithm presented in this article allows for obtaining and using the global quality index, generating applicability not only to the commercial sphere as a quality reference and price setting, but also a measure of appreciation of processing opportunities. Indices of fuzzy quality associated with wheat lots using a fuzzy model offer the opportunity to develop local markets through quality certification.
Lignocelluloses residues from the post-harvest crop are receiving great scientific attention nowa... more Lignocelluloses residues from the post-harvest crop are receiving great scientific attention nowadays. Generally, the composite materials based on lignocelluloses waste present low density and weight, and better insulation properties compared with those petroleum-based. This study presents the results of experimental investigations regarding soundproofing capabilities for a composite material based on expanded perlite (EP) and natural polymers matrix (starch) reinforced with rapeseed stalks waste. The preparation of light-weight samples of composites was performed at room temperature through a mechanical mixing process of EP with starch polymers and rapeseed residues until optimum moisture content composition was obtained. Rapeseed stalks long fibers were avoided through the preliminary dry grinding procedure, and the composite was air-dried at room temperature for 48 h. Four samples of composites with different ratio of EP and rapeseed waste were considered. The evaluation of sampl...
Membrane processes are a way to remove unwanted elements from wastewater stream. The permeability... more Membrane processes are a way to remove unwanted elements from wastewater stream. The permeability is an important parameter to filter wastewater and membrane fouling is of great interest in membrane filtration because reduce wastewater flow through the membrane. In order to improve the filtration process, many studies have investigated the use of nanoparticles added in the polymeric membranes and how much influence the permeation properties of membranes. A variety of nanoparticles have been used to modify polymer membranes, such as Al2O3, SiO2, TiO2, ZrO2, Fe3O4, Ag. Nanoparticles are used to improve the properties of membranes like hydrophilicity, permeability and fouling resistance. This paper shows the influence of the TiO2 nanoparticles with a concentration of 0.125 wt.%, on the permeation properties and dyes rejection of the PES and PSf membranes and makes a comparison with the results obtained by other authors.
This study deals with vibratory equipments dynamic behaviour and especially reveals some critical... more This study deals with vibratory equipments dynamic behaviour and especially reveals some critical aspects regarding the flexible coupling within and those influences on entire system evolution. Changing of dynamic characteristics, additional dynamic loadings and variances reducing of vibration parameters frame the main hypothesis of the research. This paper briefly presents a few theoretical assessments in terms of linear and nonlinear approaches of driving chain elements. Realistic expanded, also computational simplified models have been provided. Simulated behaviors denote that many of the reported observation regarding the serviceable dynamic distortions are correctly, and impose a set of additional instrumental tests in order to obtain a good accuracy for mathematical models.
One of the most important problem of the operating machines is the accidental failures. These fai... more One of the most important problem of the operating machines is the accidental failures. These failures generates stoppages that disturb the technological flow by introducing delays. The present paper proposes a method to control the working without failure for any equipment or machine. More exactly, each element is designed with an imposed lifespan between maintenance interventions. In these conditions, it is possible to plan precise maintenance intervention stoppages, known beforehand and with minimum stoppage time. In order to achieve these objectives, there are several stages, namely: - Identification and design of all parts, functional role as well as lifespan; - Analyzing lifespan information and setting the optimal operating time for each piece to ensure a minimum number of stoppages to restore working parameters; Re-designing the parts (where applicable) in order to change the lifespan as previously defined. This operation will involve changes in shape or material, with immed...
The use of the finite element method for dynamic analysis of multicorp systems with elastic eleme... more The use of the finite element method for dynamic analysis of multicorp systems with elastic elements implies the solving of numerous problems related to the computational techniques and the particularity of such a study in comparison with the techniques applied to the classic finite elements For such systems, special features arise from the non-linearity of the matrix coefficients appearing in the differential equation system that describe the mechanical system response and the occurrence of additional terms within these equations. In the paper a comparison is made between the finite element results of the modal response considering the third degree polynomial shape functions and the fifth degree polynomial shape functions. It is also analyzed how the number of finite elements considered for the analysis of a beam can influence the obtained results.
The paper presents a new kind of one piece compensatory coupling which function principle puts it... more The paper presents a new kind of one piece compensatory coupling which function principle puts it out from all the known categories. It is also presented the static forces state in the active zone of the coupling. In order to get the up mentioned aim, it is used the finite element programme (F.E.P.), which determines the characteristic dimensions of the coupling too.
This work presents a practical solution intended for dynamic diagnosis of the technical systems b... more This work presents a practical solution intended for dynamic diagnosis of the technical systems based on a set of computational methods for processing and analyzing of the acquired signals. This ensemble of methods leads to the joint time-frequency evaluations and assures a multiple way to estimate the potential damages of certain parts of the tested system. Short-Time-Fourier-Transformation, Cepstrum analysis, power spectral density estimate, together with a group of stochastic estimators composes the structured procedure for dynamic diagnosis. The proposed approach of dynamic diagnosis combines the advantages of the time domain analysis, such as the simplicity and the possibility of parameters investigation during their time evolution, with the power of spectral complex evaluations, sustained by the distribution and shifting trend of spectrum. Hereby it has provided a suitable tool for characterization of spectral composition changes in time during the entire experimental tests. T...
This study deals with the problematic of vibratory equipments driving system taking into account ... more This study deals with the problematic of vibratory equipments driving system taking into account both the requirements of functional performances related to the final technological quality, and the dynamic phenomenon appears during the working cycle according to the transmission way from the energy source to the vibration generator. This analysis provides useful assessments for equipment design no matter the technological machine type. Hereby this study tries to dignify the dynamic state deviations induced by the components characteristics of the driven equipment, and to reveal the means for minimizing the parameters variances.
... Luiza DASCHIEVICI, Daniela GHELASE, Cristian SIMIONESCU University Dunarea de Jos of Galati... more ... Luiza DASCHIEVICI, Daniela GHELASE, Cristian SIMIONESCU University Dunarea de Jos of Galati, Faculty of Engineeering Braila email: daniela.ghelase@ugal.ro ... The first known documented experimental researches were made by Leonardo da Vinci, probably in 1500. ...
Abstract: The paper contains an appreciation regarding the actual stage of knowledge in metal cut... more Abstract: The paper contains an appreciation regarding the actual stage of knowledge in metal cutting field from the viewpoint of tribologic aspects and defines main aspects related to cutting factors influencing tools wearing and lastingness. The paper shows a proposal of ...
One of the reasons causing vibration for gear hob toothing is the shock at the tool’s entry, whic... more One of the reasons causing vibration for gear hob toothing is the shock at the tool’s entry, which is generated by the great length of the cutting edge entering the metal at the same time. This paper proposes a fragmentation of the cutting edge so that its length is much smaller. Moreover, the cutting scheme is also changed, so that the entire tooth line of the piece is made with four consecutive teeth of the tool. Therefore, the impact force input generating shock and vibration is significantly reduced.
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