Firas F. Qader, Barhm Mohamad, Adnan M. Hussein, Suad H. Danook
Abstract Forced convection heat transfer was studied in a horizontally heated circular pipe with constant heat flux. Porous medium was created using 1 and 3 mm stainless-steel balls (porosity: 0.3690 and 0.3912). Reynolds numbers ranged from 3,200 to 6,500 based on pipe diameter, with heat flux rates of 6,250 and 12,500 W m −2 . ANSYS Fluent simulated a 51.4 mm diameter, 5 mm thick, 304 mm long stainless-steel pipe. Results showed increased turbulence and eddy formation. Analysis revealed higher convective heat transfer coefficient, pressure drop, and Nusselt number with increasing Reynolds number. Nusselt number also increased with 1–3 mm ball diameter. 6% porosity increase reduced pressure drop by 84.4%. Nusselt number rose by 46.7% (Reynolds 3,200–6,500) and 4.36% (heat flux 6,250–12,500 W m −2 ).
摘要研究了水平加热恒热流密度圆管内的强制对流换热。多孔介质采用1毫米和3毫米的不锈钢球(孔隙率分别为0.3690和0.3912)。根据管径，雷诺数从3200到6500不等，热流密度为6250和12500 W m−2。ANSYS Fluent模拟了一根直径51.4 mm、厚5mm、长304 mm的不锈钢管。结果显示湍流和涡流的形成增加。分析表明，随着雷诺数的增加，对流换热系数、压降和努塞尔数增大。Nusselt数随球径增加而增加。孔隙度增加6%，压降降低84.4%。努塞尔数增加46.7%(雷诺数3200 ~ 6500)和4.36%(热流密度6250 ~ 12500 W m−2)。
{"title":"Numerical study of heat transfer in circular pipe filled with porous medium","authors":"Firas F. Qader, Barhm Mohamad, Adnan M. Hussein, Suad H. Danook","doi":"10.1556/606.2023.00869","DOIUrl":"https://doi.org/10.1556/606.2023.00869","url":null,"abstract":"Abstract Forced convection heat transfer was studied in a horizontally heated circular pipe with constant heat flux. Porous medium was created using 1 and 3 mm stainless-steel balls (porosity: 0.3690 and 0.3912). Reynolds numbers ranged from 3,200 to 6,500 based on pipe diameter, with heat flux rates of 6,250 and 12,500 W m −2 . ANSYS Fluent simulated a 51.4 mm diameter, 5 mm thick, 304 mm long stainless-steel pipe. Results showed increased turbulence and eddy formation. Analysis revealed higher convective heat transfer coefficient, pressure drop, and Nusselt number with increasing Reynolds number. Nusselt number also increased with 1–3 mm ball diameter. 6% porosity increase reduced pressure drop by 84.4%. Nusselt number rose by 46.7% (Reynolds 3,200–6,500) and 4.36% (heat flux 6,250–12,500 W m −2 ).","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135590520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This work proposes an extended numerical scheme based on the finite volume method that is intended to solve a new morphodynamic model with porosity. The St-Venant equations and the Exner equation are coupled in this model, accounting for the variation of the porosity function . In the morphodynamic system, the Jacobian matrix's sign is taken into account when reconstructing the numerical fluxes using an improved Roe's approach to assure correct numerical computations.
{"title":"A finite volume scheme for solving an alternative morphodynamic model with porosity","authors":"Abdelhafid Moumna","doi":"10.1556/606.2023.00907","DOIUrl":"https://doi.org/10.1556/606.2023.00907","url":null,"abstract":"Abstract This work proposes an extended numerical scheme based on the finite volume method that is intended to solve a new morphodynamic model with porosity. The St-Venant equations and the Exner equation are coupled in this model, accounting for the variation of the porosity function . In the morphodynamic system, the Jacobian matrix's sign is taken into account when reconstructing the numerical fluxes using an improved Roe's approach to assure correct numerical computations.","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135592764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Abbas, Talib K. Q. Alsheakayree, Hussain M. Ashour Al Khuzaie, H. Sultan
A railway on 4 m height embankment is being built in the south of Iraq. The railway alignment is extending on a compressible soil experienced impermissible settlement according to the results of soil investigation of the soil at the project site. A trial for reducing the settlement was done adopting sand piles. Nonlinear analysis was conducted to evaluate the settlement of soil before and after using the proposed technique.The results indicated that without any improvement, the expected total settlement of the railway embankment on the compressible clay layer is 170.2 mm. By inserting granular piles of diameter 0.3 m, it was obtained settlement decreases to 88.7 mm with reduction being in range of ∼48%.
{"title":"Improvement of subgrade soil with sand columns for construction railway embankment: A case study","authors":"B. Abbas, Talib K. Q. Alsheakayree, Hussain M. Ashour Al Khuzaie, H. Sultan","doi":"10.1556/606.2023.00818","DOIUrl":"https://doi.org/10.1556/606.2023.00818","url":null,"abstract":"A railway on 4 m height embankment is being built in the south of Iraq. The railway alignment is extending on a compressible soil experienced impermissible settlement according to the results of soil investigation of the soil at the project site. A trial for reducing the settlement was done adopting sand piles. Nonlinear analysis was conducted to evaluate the settlement of soil before and after using the proposed technique.The results indicated that without any improvement, the expected total settlement of the railway embankment on the compressible clay layer is 170.2 mm. By inserting granular piles of diameter 0.3 m, it was obtained settlement decreases to 88.7 mm with reduction being in range of ∼48%.","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47035435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Spodyniuk, I. Antypov, V. Trokhaniak, V. Kaplun, O. Voznyak, O. Savchenko, I. Sukholova
The efficiency of using photovoltaic panels significantly depends on the climatic conditions and the power of the consumer. The evaluation of the efficiency of using the battery of the photovoltaic panel depending on the climatic conditions and the power of the consumer was carried out by the method of simulation modeling. A new type of storage battery allows to accumulate excess and compensate for the energy deficit due to the capacity of the batteries, and in case of their complete discharge - due to connection to other sources of electrical and thermal energy. The temperature field on the surface of the solar panel is constructed based on numerical simulation. The temperature ranges from +70.4 to +127.5 °C. In the main area of the panel, the heat flow ranged from 3,200 to 7000 W m−2.
使用光伏板的效率很大程度上取决于气候条件和消费者的功率。通过仿真建模的方法，根据气候条件和用户功率对光伏板电池的使用效率进行了评估。一种新型的储能电池可以积累多余的能量，并弥补由于电池容量而导致的能量不足，以及由于与其他电能和热能来源的连接而导致的电池完全放电。在数值模拟的基础上，构建了太阳能电池板表面的温度场。温度范围为+70.4至+127.5°C。面板主区域的热流范围为3200 ~ 7000 W m−2。
{"title":"Development of the design of accumulatory battery of the photovoltaic solar panel","authors":"N. Spodyniuk, I. Antypov, V. Trokhaniak, V. Kaplun, O. Voznyak, O. Savchenko, I. Sukholova","doi":"10.1556/606.2023.00872","DOIUrl":"https://doi.org/10.1556/606.2023.00872","url":null,"abstract":"The efficiency of using photovoltaic panels significantly depends on the climatic conditions and the power of the consumer. The evaluation of the efficiency of using the battery of the photovoltaic panel depending on the climatic conditions and the power of the consumer was carried out by the method of simulation modeling. A new type of storage battery allows to accumulate excess and compensate for the energy deficit due to the capacity of the batteries, and in case of their complete discharge - due to connection to other sources of electrical and thermal energy. The temperature field on the surface of the solar panel is constructed based on numerical simulation. The temperature ranges from +70.4 to +127.5 °C. In the main area of the panel, the heat flow ranged from 3,200 to 7000 W m−2.","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43491216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Speech scrambling aims to distort speech signals to prevent unauthorized listeners from understanding them, but conventional techniques are vulnerable to attacks. Therefore, more robust and secure speech scrambling algorithms are needed to ensure sensitive communication security. A proposed scheme uses a particle swarm optimization algorithm to generate a random key and optimize the level of noise in the scrambled signal, along with two transformations Multiwavelet and Arnold techniques to improve complexity and security. The proposed algorithm has been evaluated using various performance measurements and has demonstrated superior encryption performance than other similar audio encryption schemes with key space equal to 128 × 2.718. Further research and development in speech scrambling are essential to guarantee secure communication in sensitive contexts such as military and intelligence.
{"title":"Speech scrambler with multiwavelet, Arnold Transform and particle swarm optimization","authors":"Zahraa A. Hasan, S. Hadi, W. A. Mahmoud","doi":"10.1556/606.2023.00878","DOIUrl":"https://doi.org/10.1556/606.2023.00878","url":null,"abstract":"Speech scrambling aims to distort speech signals to prevent unauthorized listeners from understanding them, but conventional techniques are vulnerable to attacks. Therefore, more robust and secure speech scrambling algorithms are needed to ensure sensitive communication security. A proposed scheme uses a particle swarm optimization algorithm to generate a random key and optimize the level of noise in the scrambled signal, along with two transformations Multiwavelet and Arnold techniques to improve complexity and security. The proposed algorithm has been evaluated using various performance measurements and has demonstrated superior encryption performance than other similar audio encryption schemes with key space equal to 128 × 2.718. Further research and development in speech scrambling are essential to guarantee secure communication in sensitive contexts such as military and intelligence.","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49648687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With the development of society and economy, people pay more and more attention to thematic landscape architectural design featuring various cultures. Landscape architectural design is no longer only satisfied with the standardized, identical design style, but should focus on some specific cultural communication functions. In the thematic landscape architectural design, the use of cultural symbols can reflect the characteristics of the park. Through some research and practical design, the design method of using cultural symbols in landscape architectural design is summarized: from finding cultural elements to design language transformation.
{"title":"Applied research on cultural symbols in landscape architectural design","authors":"Chao Ren, Jinding Yuan, Gabriella Medvegy","doi":"10.1556/606.2023.00793","DOIUrl":"https://doi.org/10.1556/606.2023.00793","url":null,"abstract":"With the development of society and economy, people pay more and more attention to thematic landscape architectural design featuring various cultures. Landscape architectural design is no longer only satisfied with the standardized, identical design style, but should focus on some specific cultural communication functions. In the thematic landscape architectural design, the use of cultural symbols can reflect the characteristics of the park. Through some research and practical design, the design method of using cultural symbols in landscape architectural design is summarized: from finding cultural elements to design language transformation.","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43396007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The application of natural ventilation strategies in high-rise office buildings is considered one of the most promising trends to address high energy performance and enhance the indoor thermal comfort levels in interior office spaces. In this regard, this study attempts to assess the potential of natural ventilation strategies of a specific, previously investigated, envelope design of a high-rise office building located in a temperate climate zone. Different summer natural ventilation approaches were tested using the building energy simulation program IDA ICE 4.8, evaluating thermal comfort and energy demand. The findings indicated that considerable energy savings can be achieved, compared to conventional mechanical ventilation and air conditioning systems.
{"title":"Natural ventilation in high-rise office building – Comfort and energy performance","authors":"Basma Naili, I. Háber, I. Kistelegdi","doi":"10.1556/606.2023.00839","DOIUrl":"https://doi.org/10.1556/606.2023.00839","url":null,"abstract":"The application of natural ventilation strategies in high-rise office buildings is considered one of the most promising trends to address high energy performance and enhance the indoor thermal comfort levels in interior office spaces. In this regard, this study attempts to assess the potential of natural ventilation strategies of a specific, previously investigated, envelope design of a high-rise office building located in a temperate climate zone. Different summer natural ventilation approaches were tested using the building energy simulation program IDA ICE 4.8, evaluating thermal comfort and energy demand. The findings indicated that considerable energy savings can be achieved, compared to conventional mechanical ventilation and air conditioning systems.","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49131162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study presents the frequency control of hybrid deregulated power system. The power system is supplied with appropriate system non-linearity's for practicality. A resilient model predictive control based two degree of freedom proportional integral derivative controller is designed. The Covid-19 based optimization algorithm is applied for optimization purpose. The impact of solar and wind on system dynamics are also examined. Further, the capacitive energy storage is also incorporated to check its influence. The distribution companies' participation matrix changes with market fluctuations, so the matrix is varied to check its impact. Lastly, sensitivity assessment is performed to analyze the strength of proposed controller optimized gains achieved under nominal conditions.
{"title":"Frequency control of deregulated power system using C19-BOA technique","authors":"Samreen Tabassun Mir, M. Sandhu, Anmol Goyal","doi":"10.1556/606.2023.00877","DOIUrl":"https://doi.org/10.1556/606.2023.00877","url":null,"abstract":"This study presents the frequency control of hybrid deregulated power system. The power system is supplied with appropriate system non-linearity's for practicality. A resilient model predictive control based two degree of freedom proportional integral derivative controller is designed. The Covid-19 based optimization algorithm is applied for optimization purpose. The impact of solar and wind on system dynamics are also examined. Further, the capacitive energy storage is also incorporated to check its influence. The distribution companies' participation matrix changes with market fluctuations, so the matrix is varied to check its impact. Lastly, sensitivity assessment is performed to analyze the strength of proposed controller optimized gains achieved under nominal conditions.","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45302087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Multimodal biometric systems have been widely implemented in a variety of real-world scenarios due to their ability to overcome limitations associated with unimodal biometric systems. This paper is focused on the combination of the face, ear and gait in a unified multimodal biometric identification system using handcrafted features. These approaches provide robust and discriminative features to solve the biometric problem. In this research, speed up robust features and histogram of oriented gradients approaches have been used to extract features from face, ear and gait. The extracted features are optimized using genetic algorithm and classified using Levenberg-Marquardt backpropagation neural network. The system performance is evaluated on constrained and unconstrained dataset conditions.
{"title":"Multimodal biometric recognition using fused handcrafted features","authors":"H. Mehraj, A. H. Mir, Farkhanda Ana","doi":"10.1556/606.2023.00786","DOIUrl":"https://doi.org/10.1556/606.2023.00786","url":null,"abstract":"Multimodal biometric systems have been widely implemented in a variety of real-world scenarios due to their ability to overcome limitations associated with unimodal biometric systems. This paper is focused on the combination of the face, ear and gait in a unified multimodal biometric identification system using handcrafted features. These approaches provide robust and discriminative features to solve the biometric problem. In this research, speed up robust features and histogram of oriented gradients approaches have been used to extract features from face, ear and gait. The extracted features are optimized using genetic algorithm and classified using Levenberg-Marquardt backpropagation neural network. The system performance is evaluated on constrained and unconstrained dataset conditions.","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42361692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rasha Ali Kamil, Huda M. Atiea, Ali Abbas Kadhem, L. A. Alasadi, Q. A. Jabal
In this article, polymer-modified concrete was studied to present the effect of using additives on its mechanical properties. This will be achieved by employing a high-performance super plasticizing admixture that significantly enhances polymer-modified concrete mechanical capabilities. The study indicates that the polymer styrene-butadiene rubber (used increases concrete mechanical properties by 10% by weight. When the dosage exceeds 10% by weight of cement, the compressive, tensile, and flexural strengths of polymer-modified concrete are diminished. With the addition of a superplasticizer with a ratio of 1.2%, regular polymer-modified concrete compressive strength has increased from 34.3 to 42.9 MPa for a 10% polymer/cement ratio. Additionally, this superplasticizer enhanced the Material's flexural and tensile strength.
{"title":"Improvement of the mechanical properties of polymer-modified concrete by using PC superplasticizer","authors":"Rasha Ali Kamil, Huda M. Atiea, Ali Abbas Kadhem, L. A. Alasadi, Q. A. Jabal","doi":"10.1556/606.2023.00742","DOIUrl":"https://doi.org/10.1556/606.2023.00742","url":null,"abstract":"In this article, polymer-modified concrete was studied to present the effect of using additives on its mechanical properties. This will be achieved by employing a high-performance super plasticizing admixture that significantly enhances polymer-modified concrete mechanical capabilities. The study indicates that the polymer styrene-butadiene rubber (used increases concrete mechanical properties by 10% by weight. When the dosage exceeds 10% by weight of cement, the compressive, tensile, and flexural strengths of polymer-modified concrete are diminished. With the addition of a superplasticizer with a ratio of 1.2%, regular polymer-modified concrete compressive strength has increased from 34.3 to 42.9 MPa for a 10% polymer/cement ratio. Additionally, this superplasticizer enhanced the Material's flexural and tensile strength.","PeriodicalId":35003,"journal":{"name":"Pollack Periodica","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47792584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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