bluuebunny/crossref_metadata_2025 huggingface dataset:
Hubungan Literasi Media Sosial Pustakawan Perguruan Tinggi dengan Kualitas Pemanfaatan e-Resources Perpustakaan
Authors: Safira Fidan , Irawati Indira
Published: June 2020

Fenomena banjir informasi dalam media sosial tidak selalu menyediakan informasi yang akurat. Kemampuan dalam mencari, memilih, memilah dan menggunakan informasi dalam dunia digital disebut sebagai literasi media. Kemampuan literasi media yang baik sangat berpotensi menghasilkan informasi yang berkualitas. Penelitian ini bertujuan untuk mengetahui keeratan hubungan antara variabel literasi media sosial dengan variabel kualitas pemanfaatan e-resources. Acuan teori yang digunakan dalam penelitian, yaitu literasi media sosial terdiri dari tiga aspek kemampuan, yaitu kemampuan teknis, kemampuan kognitif dan kemampuan afektif. Serta konsep kualitas pemanfaatan e-resources yang mencakup lima aspek yaitu: pemahaman kemutakhiran informasi (currency), pemahaman kesesuaian informasi (relevancy), pemahaman kepemilikan informasi (authority), pemahaman ketepatan informasi (accuracy) dan yang terakhir adalah pemahaman alasan publikasi informasi (purpose). Adapun responden penelitian ini adalah 65 pustakawan perguruan tinggi dari total populasi sebesar 645 pustakawan. Hasil penelitian ini menunjukan bahwasannya keseluruhan variabel memiliki hubungan yang cukup kuat antara variabel literasi media sosial dengan variabel kualitas pemanfaatan e-resources dengan nilai korelasi sebesar 0,684. Meskipun nilai korelasi antara kemampuan teknis dengan variabel kualitas pemanfaatan e-resources hanya 0,170 yang artinya memiliki yang sangat lemah.
Model Knowledge Management di Perpustakaan Universitas Padjadjaran
Authors: Wulandari Eko Retno , Nurisani Risa
Published: June 2020

Knowledge Management mempunyai peran yang semakin penting dalam organisasi di berbagai industri. Melalui Knowledge Management, organisasi berusaha untuk memperoleh atau menciptakan pengetahuan yang berpotensi, bermanfaat dan membuatnya tersedia bagi anggota organisasi sehingga dapat digunakan pada waktu dan tempat yang tepat untuk secara positif mempengaruhi kinerja organisasi. Perpustakaan Universitas Padjadjaran belum mengelola pengetahuan yang ada secara maksimal. Pengelolaan pengetahuan di perpustakaan Universitas Padjadjaran masih terbatas pada pengetahuan eksplisit contohnya teksbook, jurnal, ebook, e-journal, skripsi, tesis, dan disertasi, padahal masih banyak pengetahuan eksplisit dan tacit yang dapat dikelola sehingga membawa manfaat bagi civitas akademika dan institusi. Tujuan penelitian ini adalah adanya model usulan Knowledge Management di perpustakaan Universitas Padjadjaran. Penelitian dilakukan dengan menggunakan analisis SWOT untuk kemudian diperoleh model KM di Perpustakaan Universitas Padjadjaran. Hasil penelitian diperoleh model usulan proses Knowledge Management di Perpustakaan Universitas Padjadjaran yaitu knowledge creation (penciptaan pengetahuan), knowledge acquisition (akuisisi pengetahuan), knowledge storage (penyimpanan pengetahuan) knowledge sharing (berbagi pengetahuan), dan knowledge application (aplikasi pengetahuan).
Indeksasi Jurnal di Lingkungan Universitas Lancang Kuning
Authors: Sudiar Nining , Latiar Hadira
Published: June 2020

Penelitian ini bertujuan untuk menganalisis perkembangan indeksasi jurnal yang ada di Universitas Lancang Kuning dengan cara menghitung jenis lembaga pengindeks dan  menghitung jumlah indeksasi yang pada setiap jurnal. Metode penelitian yang digunakan adalah deskriptif kuantitatif dengan pendekatan kepustakaan melalui penelusuran pada URL jurnal Unilak. Hasil penelitian menunjukan bahwa ada 38 jenis pengindeks dengan jumlah 143 lembaga pengindeks yang terdapat pada 16 jurnal.  Lima peringkat lembaga pengindeks terbanyak, pertama, Crossref dan Google Scholar yaitu 16 jurnal atau 18,83%, kedua Garuda sebanyak 11 jurnal atau 7,69%, ketiga OCLC WorldCat sebanyak 10 jurnal atau 6,99 %, keempat ada pada Bielefels Academic Search Engine (BASE) yaitu 9 jurnal atau 6,29 % dan yang kelima ada pada Science and Technology Index (Sinta) dengan jumlah 8 jurnal atau 5, 59%. Dapat disimpulkan bahwa lembaga pengindeks yang paling banyak dimiliki jurnal Unilak adalah lembaga pengindeks bereputasi rendah yaitu 95,11 %, lembaga pengindeks bereputasi sedang 4,89% dan belum memiliki lembaga pengindeks bereputasi tinggi seperti Scopus dan Thomson.
Penerapan Blended Librarian di Era Digital (Studi Kasus di Perpustakaan Universitas Muhammadiyah Yogyakarta)
Authors: Qurotianti Aidilla
Published: June 2020

Era digital merupakan tantangan bagi pustakawan, terutama pustakawan akademik di perpustakaan universitas. Demi menjunjung Tri Dharma Perguruan Tinggi di universitas, perpustakaan perguruan tinggi harus menyediakan layanan yang mengikuti pola kebutuhan informasi dari kalangan akademik. Selain meningkatkan layanan dan fasilitas, perpustakaan juga harus meningkatkan kemampuan dan keahlian sumber daya manusia di sana, yaitu pustakawan. Tidak hanya mampu mengolah bahan pustaka, tetapi pustakawan akademik juga harus memiliki kompetensi di bidang teknologi informasi dan memiliki peran dalam proses peningkatan pembelajaran mahasiswa. Kemampuan dalam menggabungkan ketiga kombinasi ini disebut blended librarian. Salah satu perpustakaan perguruan tinggi yang telah memiliki pustakawan dengan kemampuan blended librarian yaitu Perpustakaan Universitas Muhammadiyah Yogyakarta. Berdasarkan pemaparan tersebut, peneliti tertarik pada penelitian tentang implementasi blended librarian di era digital di Perpustakaan Universitas Muhammadiyah Yogyakarta. Penelitian ini adalah penelitian deskriptif kualitatif dengan menggunakan metode studi kasus.  Hasil dari penelitian ini adalah implementasi blended librarian di Universitas Muhammadiyah Yogyakarta adalah 1) Menyediakan dan mengelola sumber referensi; 2) Menyediakan fasilitas yang mendukung learning commons; 3) Mengoptimalkan TIK untuk akses informasi; 4) Sebagai penghubung ke sumber lain di luar universitas; 5) User Education; 6) Literasi Informasi; 7) Pencegahan Plagiarisme; 8) Pelatihan Manajer Referensi; dan 9) Pendamping Dosen.
Pemetaan Bibliometrik Perkembangan Publikasi Ilmiah Sains Terbuka Periode Tahun 2000-2019
Authors: Tupan Tupan
Published: June 2020

Kajian ini melakukan pemetaan bibliometrik tentang perkembangan penelitian sains terbuka berbasis data scopus periode tahun 2000-2019 yang bertujuan untuk mengetahui  produktivitas publikasi Ilmiah tentang sains terbuka berdasarkan tahun; jurnal Inti yang mempublikasikan tentang penelitian  sains terbuka; jumlah penulis terproduktif; jumlah publikasi ilmiah tentang sains terbuka  berdasarkan afiliasi/ lembaga, negara, tipe dokumen; dan sponsor penandanaan; serta untuk  memetakan perkembangan penelitian sains terbuka  melalui clustering kata kunci menggunakan software VOSviewer. Kajian ini dilakukan melalui penelusuran informasi pada database Scopus menggunakan kata kunci “open science”. Selanjutnya, data dari database scopus dieksplorasi sesuai tujuan penelitian. Lebih lanjut,  software VOSviewer digunakan untuk memvisualisasikan perkembangan penelitian tentang sains terbuka. Hasil penelitian menunjukkan bahwa pertumbuhan publikasi ilmiah  tentang sains terbuka yang terindeks di scopus  puncaknya  terjadi pada tahun 2018 yaitu sebanyak 230 publikasi.  Jurnal inti yang mempublikasikan publikasi ilmiah sains terbuka terbanyak adalah Royal Society Open Science  sebanyak 26 publikasi, kemuadian dsusul Journal of Physics Conference Series 23 publikasi, Nature 18 publikasi. Penulis yang paling produktif  menulis tentang  open science adalah Quick R  dari Indiana University. Publikasi ilmiah sains terbuka yang terbanyak mendapatkan sponsor penandanaan dari National Science Foundation sebesar 54 publikasi. Hasil pemetaan menggunakan sofware VOSviewer menunjukkan bahwa perkembangan publikasi sains terbuka terbagi menjadi 6 kluster.
Monumentos y Arte urbano: Percepciones actitudes y valores en el caso de la ciudad de Manizales
Authors: Santofimio-Ortiz Rodrigo , Pérez-S Sandra Milena
Published: June 2020

¿Pueden los monumentos y el arte urbano propiciar elementos interpretativos y comprensivos acerca de la ciudad? ¿Qué develan sus actores? ¿Qué pasa con el espacio público? Como soporte metodológico se proponen el enfoque del “construccionismo social”, además de las representaciones sociales y la técnica de entrevistas a actores sociales, el trabajo etnográfico y bibliografía referida al tema. La relación entre los monumentos, el arte urbano y el espacio público en la ciudad, si y sólo si se plantea de manera envolvente y dialéctica, facilitaría su apropiación y disfrute entre los actores; así mismo, la posibilidad de reivindicar una forma de sustraer el espacio público a la lógica financiera, restrictiva y de valor el capitalismo contemporáneo; puede concluirse, entonces, para el caso de Manizales estas apuestas relacionales y de reivindicación se expresan en la Torre del Cable, y en la obra de arte urbano Desde Chipre, las cuales resultan interesantes y sugestivas para los estudios sobre la ciudad contemporánea.
Lex coronavirus. Włoskie prawo w walce z pandemią
Authors: Urbaniak Monika
Published: June 2020

An epidemic caused by the coronavirus SARS-CoV-2 has been existed in Europe and worldwide for several weeks now. On 11 March 2020, the WHO declared it a global pandemic. At the time of writing, Europe, in particular Italy, is the largest outbreak of coronavirus. Italy is attempting to tackle the virus with increasingly drastic legal measures. On 31 January 2020, its Council of Ministers declared a state of emergency related to the sanitary risk of coronavirus infection. Italy has started the fight against the virus using two legal instruments: the first is the Council of Ministers’ declaration of a six-month state of emergency on 31 January 2020, and the second is a decree-law (decreto legge) issued by the Prime Minister temporarily restricting the freedom of movement throughout the state. In exceptional cases, the Italian Government has the right to issue normative legal acts. Recent legislative acts issued in Italy have undoubtedly limited the fundamental rights granted by the Constitution of 1947. These limited rights include the right of movement, but also freedom of assembly, the right to work, freedom of economic activity and freedom of conscience and religion. As a result of the legal solutions introduced, fundamental human rights are subject to justifiable restrictions in order to protect the constitutionally guaranteed right of the community to health care. In situations of epidemiological threats, protecting the lives and health of citizens is essential. Any restrictions on rights and freedoms are intended to protect these goods. However extensive these restrictions may be, in a democratic state this must be introduced under strict control and for a specified period of time linked to the duration of an epidemic.
Stosunek administracyjnoprawny w niemieckiej doktrynie prawa publicznego
Authors: Sancewicz Paweł
Published: June 2020

The notion of the administrative-legal relationship is the basis of the dogmatics of Polish administrative law. Over the years, the doctrinal framework of this concept has been established by the doctrine of public law. At the same time, an extremely fruitful dogmatics discussion about this concept both in German law and practice has taken place. Therefore, the article attempts to present discoveries of the German doctrine of public law in this area. The review of the German literature conducted in the article shows that, despite some disputes, the German authors currently believe that the administrative-legal relationship is a useful tool for the analysis of rights and obligations in comprehensive legal relations, as well as cooperative frameworks. Contemporary German scholars, who do not distinguish the concept of a legal situation, unlike in Poland, believe that as part of the modernization processes in administration, the concept of the administrative-legal relationship can be used to solve complex legal issues.The above-mentioned discoveries made by German scholars could act as significant inspiration for the Polish doctrine of public law, especially in the context of the draft to introduce an administrative agreement into Polish law. Of particular importance here is the fact that in Germany there is a different system of the legal forms of administration activity, of which an administrative agreement is a vital component. It is indicated in the paper that Polish scholars see the possibility of describing complex legal constructions by the notion of the administrative-legal relationship in the simultaneous or complementary use of the concept of the administrative-legal situation. One should consider whether the same or better effects cannot be achieved much more easily, namely by modifying the understanding in the doctrine of the notion of administrative-legal relationship, more appropriate to the analysis of cooperative frameworks in administration.
Odpowiedzialność za naruszenie międzynarodowego prawa humanitarnego przez siły pokojowe Organizacji Narodów Zjednoczonych
Authors: Stochel Jacek
Published: June 2020

Operations under the auspices of the Security Council mandate span over 70 years. Repeatedly involved in resolving armed conflicts, they have made a significant contribution to ensuring security and stability around the world. In practice, they have taken the form of operations by individual states, coalitions, other international organizations or simply as United Nations missions composed of contingents provided by Troop Contribution Countries (TCC). While operations under the auspices of the United Nations have been involved on several occasions in offensive activities under Chapter VII of the Charter of the United Nations, and the question of responsibility for these actions has been the subject of many legal analyses and judgments, missions organized by the United Nations are always recognized as neutral, and their activities as conciliatory and focused on monitoring the cessation of hostilities, or supervising the disengagement between the parties of the conflict, with the use of force limited to self-defence. Thus, such operations benefited from legal protection, and any action against them was considered a violation of international law. The current engagement of United Nations goes far beyond the traditional understanding of peacekeeping operations. UN missions are frequently authorized to employ all necessary means, up to and including the use of lethal force or even neutralization of the armed group. This creates a situation where in the light of International Humanitarian Law, such actions can be recognized as involvement in armed conflict. This article is intended to show the problems that the international community will soon face to in using United Nations’ missions as an instrument for resolving armed conflicts and as a tool for restoring peace and providing stability and securityin the area of operations. It presents the processes of decision-making and subordination, which in some circumstances might result in the United Nations missions being deprived of legal protection and, in addition, made liable for non-compliance with the provisions of International Humanitarian Law.
Gminny Program Profilaktyki i Rozwiązywania Problemów Alkoholowych jako podstawowa forma realizacji zadań własnych gminy z zakresu profilaktyki i rozwiązywania problemów alkoholowych
Authors: Biniasz-Celka Danuta
Published: June 2020

The system of preventing and resolving alcohol-related problems used in Poland gives municipalities (gminas), as territorial units, the fundamental role in it. The municipality council is obliged to establish a number of programmes on the basis of the act on municipality self-government, as well as the regulations of other acts, including the Act of 26th October 1982 on Upbringing in Sobriety and Counteracting Alcoholism (A.U.S.C.A.) of the Municipality Programme for Preventing and Resolving Alcohol-related Problems (LCPP&RAP). The programme takes into account the areas of action listed in Article 41 section 1 of the A.U.S.C.A. and the indications included in the recommendations developed by the National Agency for Resolving Alcohol-related Problems. It should be emphasized that the implementation of tasks in the field of preventing and resolving alcohol-related problems under the programme is part of the strategy for resolving social problems, and takes into account the operational objectives set out in the National Health Programme. The regulations of the A.U.S.C.A. also provide the municipality witha significant role in implementing actions to tackle alcohol addiction. The actions are taken on three levels by: (1) appointing a local community committee for resolving problems (Article 41 section 3), (2) determining within resolutions the maximum number of permits for the sale of alcoholic beverages and the rules of locating places of sale and serving alcoholic beverages (Article 12 sections 1–3), (3) issuing permits for the sale of alcohol (Article 18 section 1) and monitoring the legitimacy of using these permits (Article 18 section 8). In addition, the LCPP&RAP provides solutions regarding forms, methods and projects undertaken by the municipality. It is important to note that the municipality self-government, as a result of decentralization of the state, has received extensive competence to conduct its own policy on alcohol-related problems, which is why its role is crucial.
Best Practices in Real Estate Cross-border Transactions
Authors: Szulc Piotr
Published: June 2020

The article presents reflections on the best practices in real estate cross border transactions.Transactions on real estate markets have several aspects that make them highly complex, mostly due to their individual nature – each property is unique in terms of its location, structure and history. Cross-border transactions on the real estate market are becoming increasingly popular as the world becomes more globalized. The growing volume of this type of transaction presents a challenge for the modern real estate lawyer. It is impossible to create an exhaustive guide setting out all the hazards occurring in such transactions. This article addresses this difficult challenge by indicating the most important of them.It is essential and extremely helpful to enter into cooperation with a local counsel who will help us to explain the local specificity and who will take the legal differences into account. In addition, other helpful tools, such as a legal due diligence report or a title insurance Policy, should be carefully considered. One cannot forget about the importance of the local culture and customs, which may prove decisive at the crucial moment of the transaction. Finally, to be effective in working with cross-border clients, lawyers must have a good understanding of how people think and make decisions, and must possess good people skills. Respect for local customs and traditions, as well as understanding the local legal system while securing clients’ interests, is the key to a successful transaction.
Zakres przedmiotowy tzw. uchwały krajobrazowej. Uwagi na tle wyroku Wojewódzkiego Sądu Administracyjnego w Gdańsku z 18 września 2018 r., sygn. II SA/Gd 328/18
Authors: Lizak Agata
Published: June 2020

The text concerns an analysis of theses and justification for the judgment of Province Administrative Court in Gdańsk dated 18 September 2018 (case no. II SA/Gd 328/18). Although the judgment is based on particular factual state of affairs, its conclusions seem to be connected with common problems in the area of so-called ‘landscape acts’ adopted at the municipal level. Firstly, the judgment states that landscape acts may refer to campaign materials presented in connection with elections or referendum. In the commentary, this approach is approved, although the reasoning is developed via a detailed interpretationof the spatial management and planning act and electoral code. Later in the judgment it is claimed that landscape acts may cover rules of locating advertisements nearby elements of the road infrastructure. Moreover, this standpoint is shared in the gloss, detailed relations between landscape act and act on public roads as well as judgments in similar cases have been additionally presented. The last issue raised in the judgment was the problem of the legal grounds of imposing an obligation to maintain small architecture objects, advertisement boards /units and fences in the proper condition. As the court claimed, this is possible, because maintenance of the object is the element of its location, and this is also connected with the obligation to use high-quality materials. Moreover, it is stated that the problem of maintaining these objects has not been fully regulated in building law. This approach is accepted in the gloss, although attention is drawn to some inconsistencies in the justification, as well as to the possibility of raising other, moreaccurate arguments by the court.
A Computational Study of Effect of Thickness on Mild Steel Fracture
Authors: Permanoon Ali , Akhaveissy Amir Houshang
Published: June 2020

Fracture and crack propagation in various materials have always attracted the attention of researchers. Therefore, an investigation of the fracture of construction steel as one of the most extensively used materials in the industry is of necessity. Numerical modeling has been always a complementary aid to the laboratory sample analysis. One important issue is to study the behavior of laboratory specimens based on their dimensions, which finds further significance in fracture problems. In the current research, the effect of sample thickness on the crack behavior is investigated via a compact tension specimen. Accordingly, using numerical result validation, the behavior of the numerical samples along the thickness is examined and used as a complement to the experimental results. By modeling and analyzing numerical samples with different thicknesses (0.1 < B/W < 2), an equation is proposed. The equation can be used to determine in what percentage of the thickness from the free edge the behavior is either plane stress or plane strain.
Measurement of Water Content in Metal Powders
Authors: Lefebvre Louis-Philippe , Dai Jiajie , Thomas Yannig , Daroszewska Malgosia , Martinez-Rubi Yadienka
Published: June 2020

It is recognized that humidity affects the properties of metallic powders (e.g., flowability, density, composition). Although standards exist to evaluate the water content in various materials, there is presently no standard method validated or specifically adapted for the evaluation of the water content in metallic powders. This article evaluates the water content in titanium powders using different techniques (gravimetry, Karl Fischer titration, quantification of volatiles with a relative humidity sensor). The effect of measurement conditions, particle size, and types of powder were investigated. The results showed that the adsorption of water is a function of the relative humidity in the environment and the characteristics of the powders. The relative humidity in the laboratory has, however, limited effect if the exposure of the powder to the environment is limited prior to the measurements. Water adsorption/desorption is a function of the surface area of the powder. The measured values were underestimated as the methods used (i.e., heating at temperature lower than 275°C) did not allow recovering all the water from the powders (i.e., chemisorb water is strongly bonded to the surface and cannot be completely desorbed at temperatures lower than 275°C). Although some variability has been observed, the measurement of volatiles with the relative humidity sensor allowed discriminating powders with water contents ranging from 0 to 108 ppm. The amount of water measured using the gravimetric technique was not sensitive enough to precisely monitor the small amount of water adsorb/desorb on the powders investigated in this study. Additional studies are needed to assess the variability and reproducibility of the results and evaluate the techniques on other types of metallic powders.
Processing of Microscale Aluminum Foamed Particles
Authors: Key D. , Daoush Walid M. , Morsi K.
Published: June 2020

Metallic foams have been gaining significant interest because of their unique properties. The present study investigates the processing of microscale particles of aluminum–titanium dihydride foaming precursors, together with their foaming characteristics. The external and internal features and dimensions of these precursor particles were found to be highly dependent on the mechanical milling process and the use of a process control agent (methanol) during milling. The effect of the foaming environment on the foaming characteristics was investigated. Foaming in argon was found to yield better foaming characteristics than that in air.
A simplified human head finite element model for brain injury assessment of blunt impacts
Authors: Hassan M.H.A. , Taha Z. , Hasanuddin I. , Majeed A.P.P.A. , Mustafa H. , Othman N. A.
Published: June 2020

Blunt impacts contribute more than 95% of brain trauma injuries in Malaysia. Modelling and simulation of these impacts are essential in understanding the mechanics of the injuries to develop a protective equipment that might prevent brain trauma. Various finite element models of human head have been developed, ranging from two-dimensional models to very complex three-dimensional models. The aim of this study is to develop a simplified three-dimensional human head model with low computational cost, yet capable of producing reliable brain responses. The influence of different head-neck boundary conditions on the brain responses were also examined. Our model was validated against an experimental work on human cadaver. The model with free head-neck boundary condition was found to be in good agreement with experimental results. The head-neck joint was found to have a significant influence on the brain responses upon impact. Further investigations on the head-neck joint modelling are needed. Our simplified model was successfully validated against experimental data on human cadaver and could be used in simulating blunt impact scenarios.
Phase analysis and microstructure study of sintered Ni-Cr composites containing MoS2, Ag and CaF2 additives as solid lubricants
Authors: Mohamad Wan Farhana , Khan Amir Azam , Ahmad Faiz , Yassin Abdullah
Published: June 2020

Ni-Cr based composites with and without the addition of solid lubricants (MoS2, Ag and CaF2) were prepared by powder metallurgy method. The samples were sintered at different temperatures (1000oC, 1100oC and 1200oC) under controlled atmosphere and various holding times. The physical properties such as sintered density, relative density and porosity were studied. The microstructures and phase studies of the Ni-Cr based composites were conducted using Scanning Electron Microscope (SEM) and X-Ray Diffraction Analysis (XRD) while the hardness of the composites was measured by the Vickers Micro Hardness Tester. The results revealed that as the sintering temperature was increased, the sintered density, relative density and hardness also increased while the porosity was reduced. At the sintering temperature of 1200oC, the relative density reached its maximum value. SEM and XRD analysis confirmed the existence of MoS2 and Ag in sintered samples. MoS2 and Ag were not mainly dissolved and/or decomposed even after sintering at 1200oC
Study of the conrod deformation during piston interaction with liquid in the internal combustion engine cylinder
Authors: Dmitriev Sergey Alekseevich , Khrulev Alexander Eduardovich
Published: June 2020

The paper analyzes the deformation of the connecting rod stem with buckling due to water ingress into the internal combustion engine cylinder (the so-called hydrolock). A method is presented that has been developed to perform calculations of stem deformation in the process of compressing air with liquid in an internal combustion engine cylinder. The method is based on solving a system of differential equations for pressure and temperature in the cylinder, followed by calculating the compression force acting on the connecting rod. A carried-out simulation of the compression process demonstrates the dependence of the air pressure in the cylinder, the stress and the strain of the connecting rod on the fill ratio of the combustion chamber with liquid. The calculations performed according to the classical theory of resistance of materials have shown that the connecting rod with the buckling of the stem begins to deform when the liquid fills the combustion chamber to a minimum of 80%. With the increase in the amount of liquid, the deformation of the conrod increases, and when the level of liquid filling is so significant that it exceeds the volume of the combustion chamber, the conrod stem deformation reaches extreme values. It is shown that under these conditions after the hydrolock occurs the engine may fail due to the piston wedging the crankshaft in the bottom dead center position.
Influence of guide vanes on the flow fields and performance of axial pump under unsteady flow conditions: Numerical study
Authors: Al-Obaidi Ahmed Ramadhan
Published: June 2020

Influence of different guide vanes on structural of flow field and axial pump performance under unsteady flow is carried out using numerical method. A three-dimensional axial flow pump model is numerically simulated using computational fluid dynamics (CFD) method with four number of impeller blades and 3, 4, 5 and 6 guide vanes depend on the SIMPLE code, standard turbulence k-ε model as well as sliding mesh method (SMM). The static, dynamic, total pressures, shear stress, velocity magnitude and turbulent kinetic energy are the important features which affecting instability operation in the pump. By monitoring above parameters and setting different measurement pressure points, the average pressures in the pump are discussed and the effect of guide vanes on the average pressure is analyzed. The results demonstrate that the numerical calculations can provide good accurately prediction for the characteristics of internal flow in the pump. The numerical results are closed to experimental results the minimum errors of pressure differences can reach 2.5% and the maximum errors 6.5%. The guide vanes have more effect on the flow field and pressure variations especially at outlet region in the axial pump. As compared with the using various guide vanes, the pressure increases as number of vanes increase that can lead the performance of pump also increases. Pressure differences in the pump at variety mass flow for vane 6 is higher than other vanes 3, 4 and 5 by 14.13, 11.35 and 3.85% for flow of 5 L/min. Further, the dynamic pressure differences for design flow between different vanes 6, 5, 4 and 3 are about by 2.87, 7.26 and 8.51% respectively.
RANS study of very high Reynolds-number plane turbulent Couette flow
Authors: Sherikar Akshay , Disimile P. J.
Published: June 2020

The objective of this study is to expound on the deliverables of a steady-state RANS (Reynolds Averaged Navier Stokes) simulation in one of the simplest flows, Couette flow, at a very high Reynolds number. To that end, a process to perform better grid sensitivity testing is introduced. Three two-equation turbulence models ( , , and ) are compared against each other as well as pitted against formal literature on the subject and core flow velocities, slopes, wall-bounded velocities, shear stresses and kinetic energies are analyzed.  applied with enhanced wall functions is consistently found to be in better agreement with previous studies. Finally, plane turbulent Couette flow at  51,099, the range at which it has not been studied experimentally, numerically or analytically in former studies, is simulated. The results are found to be consistent with the trends asserted by literature and preliminary computations of this study.
Magnetic field enhancement technique in the fluid flow gap of a single coil twin tube Magnetorheological damper using magnetic shields
Authors: Ganesha A. , Patil Suraj , Kumar Prof. Nitesh , Murthy Amar
Published: June 2020

Smart dampers in the automobile suspension system bring a precise balance between the ride comfort and stability through a controllable damping coefficient. Energy absorbed by a Magnetorheological (MR) damper is a dependent function of flux density in the fluid flow gap. In this paper, magnetic field enhancement technique in the form of a single cylindrical shield and sandwich cylindrical shield is incorporated in a twin tube single coil MR damper. The field strength in different configurations of MR damper having various type of shield configuration is computationally investigated. Further, the effect of shield thickness on field strength is investigated. A significant overall improvement in the magnetic field strength is observed in the MR damper configuration having copper alloy shield.
Numerical investigation of the effect of bump and indent inside a vertical tube on the subcooled flow boiling and critical heat flux
Authors: DolatiAsl Kianoush , Abedini Ehsan , Bakhshan Younes
Published: June 2020

One of the essential industry problems is the critical heat flux (CHF) phenomenon in the flow boiling regime which leads to the temperature jumping and damaging to the systems. Increasing the vapour volume fraction decreases the heat transfer coefficient, and finally, temperature jump will occur. Also, the existence of the bumps and indent in the flow domain changes the flow pattern. In this study, by considering bumps and indent in the tube, the boiling of fluid flow in the vertical tube is discussed. For modelling and simulating the problems, the Euler-Euler model for studying the interaction of the liquid-vapour phases was used. Some models and material specifications are declared using the user-defined function (UDF) codes to the ANSYS Fluent program. The results show that the existence of bumps and indent inside the tube causes the flow of liquid phase to be less redirected in comparison to vapour phase flow due to having more momentum; therefore, at the end of the bumps in the tube, the amount of vapour volume fraction near the wall rises sharply. By increasing the flow mass flux, the vapour volume fraction at the end of bumps increases which lead to decreasing CHF value. It has also observed that if there are bumps and indents inside the tube, there will be no significant change in the liquid flow and vapour volume fraction in the other parts of the tube, as compared to the regular tube.
Effect of tube shape on the performance of a fin and tube heat exchanger
Authors: Sahel Djamel , Ameur Houari , Mellal Mustapha
Published: June 2020

A numerical study is carried out to test the effect of tube shape on heat transfer and fluid flow in a finned tube heat exchanger. The effects of different shapes (circular, flat, elliptical and oval in both orientations: left and right) are analyzed. The simulations are carried out for two-dimensional and external flow of an incompressible fluid with Reynolds numbers varying between 3000 and 20000. The results obtained indicate that the shape of the tube directly affects the thermal and dynamic behaviors of a fin and tube heat exchanger. Where the circular tube ensures higher heat transfer coefficient of about 18% than the flat tube, and it generate a moderate pressure drop of about 10% in the same conditions. Also, some reliable empirical correlations are proposed to predict the Nusselt number and the friction factor.
Injection period pressure transient behaviour of two-phase water-oil flow: A semi-analytical study
Authors: Shafeer Althaf , Hyun Lee Jang , Ganat Tarek Arbi , Habte Azeb Demisi
Published: June 2020

This paper presents a study on the pressure transient behaviour during the injection period in a vertical well in the presence of wellbore storage and skin effect. The two-phase water-oil radial flow problem is solved using a semi-analytical technique called the Laplace-Transform Finite-Difference method. Moreover, the factors that influence the degree of wellbore storage and skin effect are analysed. The results demonstrated that the effect of wellbore storage on the pressure transient behaviour is significant during the early times. Factors such as compressibility of fluid, effective wellbore volume and endpoint mobility ratio significantly affect the duration of wellbore storage. The impact of the skin during the injection period is significant on the pressure transient behaviour and could last for a longer duration. A substantial effect of skin is observed for a positive skin factor and unfavourable endpoint mobility ratio. In addition, the duration of the effect is directly proportional to the thickness of the skin zone. Hence attention must be given to the parameters that could prolong these effects and included in the solution methods to precisely interpret the injection period pressure transient behaviour for a better estimation of the reservoir and well properties.
Effect of combined drink cans and steel fibers on the impact resistance and mechanical properties of concrete
Authors: Syamsir A. , Mubin S. M. , Nor N. M. , Anggraini V. , Nagappan S. , Sofan A. M. , Muda Z. C.
Published: June 2020

This study investigated the combine effect of 0.2 % drink cans and steel fibers with volume fractions of 0%, 0.5%, 1%, 1.5%, 2%, 2.5% and 3% to the mechanical properties and impact resistance of concrete. Hooked-end steel fiber with 30 mm and 0.75 mm length and diameter, respectively was selected for this study.  The drinks cans fiber were twisted manually in order to increase friction between fiber and concrete. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the strength performance of concrete, especially the compressive strength, flexural strength and indirect tensile strength. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the compressive strength, flexural strength and indirect tensile strength by 2.3, 7, and 2 times as compare to batch 1, respectively. Moreover, the impact resistance of fiber reinforced concrete has increase by 7 times as compared to non-fiber concretes. Moreover, the impact resistance of fiber reinforced concrete consistently gave better results as compared to non-fiber concretes. The fiber reinforced concrete turned more ductile as the dosage of fibers was increased and ductility started to decrease slightly after optimum fiber dosage was reached. It was found that concrete with combination of 2% steel and 0.2% drink cans fibers showed the highest compressive, split tensile, flexural as well as impact strength.
Performance of air source air conditioning water heater using trombone coil dummy condenser with different diameter and pipe length
Authors: Aziz A. , Samri A. , Mainil R. I. , Mainil A. K.
Published: June 2020

The Air Source Air Conditioning Water Heater (ASACWH) performance as an energy source to heat water in the tank using dummy condenser type of trombone coil with different diameter and pipe length without hot water circulation has been investigated. The diameter and length of the dummy condenser pipe are intensely affected by ACWH performance. In this study, cooling capacity, Coefficient of Performance (COP), compressor power and room temperature were evaluated in three types of trombone coil (6.4 mm coil diameter with a length of 7.9 m, 6.4 mm coil diameter with a length of 5.3 m, and 9.5 mm coil diameter with a length of 5.3 m) with different cooling load variation. This study used cooling load with a variation of 0 W, 1000 W, 2000 W, and 3000 W without hot water circulation in the simulation room. It was found that the ASACWH using a pipe with a coil diameter of 6.4 mm and length of 7.9 m performed the highest cooling capacity and COP, and produced more comfortable room temperature than the other two pipes. The results indicated that when the cooling load icreased from 0 W to 3000 W, the compressor power increased by 11.3%, 6.3%, and 9.3%, using the 6.4 mm coil diameter with 7.9 m length, 6.4mm diameter of the coil with 5.3m length and 9.5mm coil diameter with 5.3m length, respectively.
Component mode synthesis and stochastic perturbation method for dynamic analysis of large linear finite element with uncertain parameters
Authors: Lamrhari D. , Sarsri D. , Rahmoune M.
Published: June 2020

In this paper, a method to calculate the first two moments (mean and variance) of the stochastic time response as well as the frequency functions of large FE models with probabilistic uncertainties in the physical parameters is proposed. This method is based on coupling of second order perturbation method and component mode synthesis methods. Various component mode synthesis methods are used to optimally reduce the size of the model. The analysis of dynamic response of stochastic finite element system can be done in the frequency domain using the frequency transfer functions and in the time domain by a direct integration of the equations of motion, using numerical procedures. The statistical first two moments of dynamic response of the reduced system are obtained by the second order perturbation method. Numerical applications have been developed to highlight effectiveness of the method developed to analyze the stochastic response of large structures.
Size-effect in microwave processing of engineering materials - A review
Authors: Gamit Dhirendra N. , Chudasama Mahesh K.
Published: June 2020

The size of material units is especially critical in manufacturing processes where thermal energy interacts with the material. The microwave energy is widely used to process the materials in industries such as food processing, chemical, manufacturing etc. due to its unique heating characteristics. In microwave processing, energy is generated and absorbed inside the material during irradiation. The energy absorbed per unit volume of the material depends upon its size. The smaller size candidate materials have more effective surface area to absorb microwave energy than the bulk ones and usually yield lesser defects. This review paper summarizes the fundamentals of size-effect, microwave–materials interaction and input/output parameters in microwave material processing. Further, size-effect in microwave processing of different type of engineering materials (metal based, ceramic based and polymer based) have been discussed in terms of energy absorption and improvement in product attributes. The challenges in microwave processing of metal based materials have been identified and opportunities have been outlined in order to improve the properties vis-à-vis particle sizes during microwave processing.
Synthesis of ZnO/ZnFe2O4 nanocomposites in organic-free media and their photocatalytic activity under natural sunlight
Authors: Rahmayeni Rahmayeni , Zulhadjri Zulhadjri , Stiadi Yeni , Harry Agusnar , Arief Syukri
Published: June 2020

Nanocomposite ZnO/ZnFe2O4 photocatalysts with different proportions of ZnFe2O4 were synthesized in organic-free media using metal nitric as precursors. The ZnO phase with hexagonal wurtzite structure and low crystallinity of ZnFe2O4 was confirmed using XRD (X-Ray diffraction). Different morphologies of the nanocomposites were obtained ranging from rice grain-like with a porous surface to homogeneous sphere-like nanoparticles as shown in Scanning Electron Microscopy (SEM) and TEM Transmission Electron Microscopy (TEM) studies. Magnetic properties measured by Visible Sampler Magnetometer (VSM) showed diamagnetic and paramagnetic behavior for the nanocomposites. Analysis with Diffuse Reflectance Spectrophotometer (DRS) UV-vis showed an increase the composition of ferrite in composites increasing its ability to absorb visible light. Photocatalytic activities of ZnO/ZnFe2O4 nanocomposites on the degradation of Rhodamine B dye reached 95.6% after 3 h under natural sunlight suggesting their suitability for sunlight driven photocatalytic applications.
The effect of Isoprenyl Ether polymer molecular structure on cementitious composites
Authors: Chee Ban Cheah , Peck Gee Ng , Ling Ling Tiong , Eng Poh Ng , Chuan Wei Oo
Published: June 2020

In order to minimize the rapid flow loss issue from the hot weather or during lengthy periods and long-distance transport, the synthesis of the isoprenyl oxy polyethylene ether (T-PEG) was introduced. However, there were scarce amount of reported literature on the influence of main and side chain densities on the fresh and hardened properties of concrete containing T-PEG polymers. This study was conducted to investigate fresh and mechanical properties of cementitious composites containing T-PEG polymers with different main and side chain densities. These T-PEG polymers were comprised of the density ratio of side chain to main chain of 1:1, 1:1.5, 1:2, 1:2.5 and 1:3.5, respectively. The laboratory tests conducted were marsh cone funnel test, standard consistency, flow retention, flexural strength and compressive strength test. The results obtained showed that the increased density ratio of side chain to main chain of T-PEG improves the fluidity of the cement paste and the flow retention ability of the cement mortar. Consequently, the mortar with T2 polymer proved a better performance on mechanical strength tests. In conclusion, the increasing main to side chain densities ratio of T-PEG polymer imposes a significant influence on the fresh and hardened properties of the concrete material produced.
Effect of corrosion on mechanical properties of the joining of materials
Authors: Abbas Mohamed , M. Abdella Galal , O. Eltai Elsadig , Gul M.
Published: June 2020

The effect of corrosion behavior in critical environmental conditions on the mechanical properties of composite/metal materials joints was investigated by immersing metalic materials into 5wt% hydrochloric acid solutions. The current  study was carried out on a single lab joint with a total thickness of 4mm; thus, a destructive test was undertaken to investigate the corrosion behavior induced degradation of mechanical properties followed by Scanning electron microscope analysis (SEM). The joined specimens were examined under both non-corrosive and corrosive environmental conditions. Moreover, the Taguchi analysis of experimental data for maximizing the required output is carried out to validate the impact and significance of input factors. Experimental results have shown that the weight losses of the mild steel and aluminum materials are 7.45% and 16.7%, respectively, in 5% wt hydrochloric acid after three weeks. The corrosive environment affected  the strength of the joints and obtained an early failure on the joint region that leads to a reduction on the strength of the materials by almost 15% compared to the non-corroded  joint. The joining of non-corroded similar steel obtained the highest maximum stress among all other specimens, where the maximum recorded stress was 140.5MPa as compared to 125MPa for corroded specimen. Furthermore, the mode of failure and hardness tests were obtained and analyzed for all specimens. A significant reduction in the hardness of the materials after exposure to the HCl acid was observed.