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"Starting from fundamentals of classical stability theory, an overview is given of the transition phenomena in subsonic, wall-bounded shear flows. At first, the consideration focuses on elementary small-amplitude velocity perturbations of laminar shear layers, i.e. instability waves, in the simplest canonical configurations of a plane channel flow and a flat-plate boundary layer. Then the linear stability problem is expanded to include the effects of pressure gradients, flow curvature, boundary-layer separation, wall compliance, etc. related to applications. Beyond the amplification of instability waves is the non-modal growth of local stationary and non-stationary shear flow perturbations which are discussed as well. The volume continues with the key aspect of the transition process, that is, receptivity of convectively unstable shear layers to external perturbations, summarizing main paths of the excitation of laminar flow disturbances. The remainder of the book addresses the instability phenomena found at late stages of transition. These include secondary instabilities and nonlinear features of boundary-layer perturbations that lead to the final breakdown to turbulence. Thus, the reader is provided with a step-by-step approach that covers the milestones and recent advances in the laminar-turbulent transition. Special aspects of instability and transition are discussed through the book and are intended for research scientists, while the main target of the book is the student in the fundamentals of fluid mechanics. Computational guides, recommended exercises, and PowerPoint multimedia notes based on results of real scientific experiments supplement the monograph. These are especially helpful for the neophyte to obtain a solid foundation in hydrodynamic stability."

"Di dalam fluida yang mengalir, terdapat lapisan yang bergerak relatif terhadap lapisan yang berdekatan sehingga timbul tegangan geser. Tegangan geser pada fluida cair sangat ditentukan oleh besarnya viskositas dinamik yang dimiliki oleh fluida itu sendiri. Penelitian tentang adanya pengaruh viskositas dinamik terhadap tegangan geser fluida cair dilakukan dengan menggunakan shear defonnation apparatus. Penelitian dilakukan dengan menggunakan 2 buah fluida cair yang berlainan nilai viskositas dinamiknya (jl), yaitu air dan minyak goreng. Eksperimen dalam penelitian ini menggunakan beads dalam pengambilan data pergerakan searah sumbu x, yang nantinya data ini diolah menjadi nilai dari gradien kecepatannya (duldy). Dengan harga viskositas dinamik, p konstan, maka akan mendapatkan tegangan geser yang terjadi. Hasil penelitian menunjukkan habwa nilai viskositas dinamik sangat berpengaruh terbadap besarnya tegangan geser yang terjadi. Karena viskositas dinamik pada minyak goreng lebih besar daripada air, maka tegangan geser yang terjadi pada minyak goreng lebih besar daripada air.

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In fluid flow, there are layers which are move relatively to near layer with the result that appear shear stress, Shear stress on liquid fluid is decided by dynamic viscosity value of that fluid. Examination about the effect of dynamic viscosity to shear & tress in liquid fluid used a shear deformation apparatus. This examination used 2 liquid fluid with different dynamic viscosity (JJ) an each other, there are water and frying oil. The experiment in this examination used beads to take data of movement in the same direction in x axis, then that data are processed to shear rate value (duldy). The constant value of dynamic viscosity appears shear stress. The result of this examination that dynamic viscosity value influences shear stress value, Shear stress of flying oil greater than shear stress of water."

"Sambungan geser berfungsi mentransfer gaya geser dari sambungan ke seluruh struktur jembatan, jadi harus didesain dengan baik. Desain terbaik terdapat pada sambungan yang memiliki beban potensial retak terbesar. Penelitian sambungan dilakukan dengan memodelkan sambungan kunci geser tunggal dengan epoxy dari jurnal rujukan dan dikembangkan dengan memberikan variasi lebar kunci, tinggi kunci bagian depan, jarak antar kunci, dan tebal epoxy pada sambungan kunci geser jamak. Pemodelan dilakukan dengan program ANSYS. Hasil pemodelan menunjukkan beban potensial retak terbesar terdapat pada sambungan dengan sudut kunci 60° untuk jarak antar kunci 66,675 mm dan 45° untuk jarak antar kunci 100,0125 mm.

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Shear key has a function to transfer shear forces from shear key to the bridge structure, so it must be designed properly. The best design can be found in shear key with the biggest load of potential cracking. Research of shear key was conducted by modeling a single shear key with epoxy of the journal reference and developed by providing several variations such as width of the key, height of the key, distance between keys, and the thickness of epoxy. Modeling done by ANSYS program. Modeling results showed that the biggest load of potential cracking resistance was found in shear key with key angle 60° for distance between keys 66,675 mm and 45° for distance between keys 100, 0125 mm."

"Sambungan kunci geser merupakan sambungan berbentuk gerigi yang terdapat di setiap pertemuan antar segmen pada jembatan beton segmental. Tujuan dari kajian ini adalah mendapatkan gambaran besar beban yang terkait dengan potensi retak yang dihasilkan dari beberapa variasi kunci geser jamak tanpa perekat. Jumlah gerigi yang digunakan sebanyak 2 buah serta variasi yang digunakan meliputi tinggi gerigi, lebar gerigi, dan jarak antar gerigi. Pemodelan numerik dilakukan untuk mendapatkan beban potensi retak yang dihasilkan dari variasi tersebut. Pada tahap awal, dilakukan validasi model dengan memodelkan kunci geser berdasarkan rujukan eksperimen terdahulu. Hasil simulasi menunjukkan bahwa variasi kunci geser sudut 45 dan jarak antar gerigi sebesar tinggi gerigi belakang menghasilkan beban potensi retak terbesar.

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Shear key connection is a joint resembling a key which is found in every meeting between segments at the segmental bridge of concrete. The purpose of this study is to obtain the potential cracking load from several variations of dry multiple shear key. The amount of keys used are two, and the variations used are the height of keys, the width of keys, and the distance between keys. To fulfill the purpose of this study, the modeling method used is numerical simulation. In the early phase of study, model validation is performed based on past experimental study. The result of modeling shows that shear key with 45 degree angle and distance between keys equal with back height of keys yields the highest load related to potential crack."

"This book gives a mathematical insight--including intermediate derivation steps-into engineering physics and turbulence modeling related to an anisotropic modification to the Boussinesq hypothesis (deformation theory) coupled with the similarity theory of velocity fluctuations. Through mathematical derivations and their explanations, the reader will be able to understand new theoretical concepts quickly, including how to put a new hypothesis on the anisotropic Reynolds stress tensor into engineering practice. The anisotropic modification to the eddy viscosity hypothesis is in the center of research interest, however, the unification of the deformation theory and the anisotropic similarity theory of turbulent velocity fluctuations is still missing from the literature. This book brings a mathematically challenging subject closer to graduate students and researchers who are developing the next generation of anisotropic turbulence models."

"Pengujian kuat geser tanah merupakan masalah yang berhubungan dengan stabilitas massa tanah. Menentukan kuat geser tanah kaolin (mineral tanah lempung) di laboratorium, terlebih dahulu dilakukan pengujian untuk menentukan Indek Properties tanah sebelum dilakukan pengujian kuat geser terhadap sample tanah. Alat yang digunakan pada pengujian ini adalah alat uji geser sudu laboratorium (vane shear test laboratory).Pengujian kuat geser digunakan untuk analisa daya dukung tanah dan stabilitas lereng dengan tujuan pengujian, untuk menentukan nilai parameter-parameter kekuatan geser dari hasil uji geser sudu (vane shear test) laboratorium dan membandingkan hasil pengujian kuat geser tanah lempung antara metode pengujian kuat geser sudu (vane shear test) dengan metode pengujian triaksial.

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Measuring of shear strength of soils to constitute problem that is engaged soiled mass stability. Determining shear strength of kaolin (clays soiled mineral) at laboratory, earlier been done tests to determine Indek Properties of kaolin before done by measuring of shear strength to soiled sample. Tool that is utilized on this test is vane shear laboratory.

Measuring of shear strength of soils to be utilized to analyse soiled advocate energy, to determine parameter of shear strength with measuring vane shear laboratory and compares the measurements of shear strength of clay among vane shear test laboratory with triaksial UU tests."

"Now in its second edition, this book clearly, concisely and comprehensively outlines the essence of turbulence. In view of the absence of a theory based on first principles and adequate tools to handle the problem, the essence of turbulence, i.e. what turbulence really is from a fundamental point of view, is understood empirically through observations from nature, laboratories and direct numerical simulations rather than explained by means of conventional formalistic aspects, models, etc., resulting in pertinent issues being described at a highly theoretical level in spite of the mentioned lack of theory.As such, the book highlights and critically reexamines fundamental issues, especially those of paradigmatic nature, related to conceptual and problematic aspects, key misconceptions and unresolved matters, and discusses why the problem is so difficult. As in the previous edition, the focus on fundamental issues is also a consequence of the view that without corresponding advances in fundamental aspects there is little chance of progress in any applications. More generally there is a desperate need for physical fundamentals of a great variety of processes in nature and technology in which turbulence plays a central role. Turbulence is omnipresent throughout the natural sciences and technology, but despite the vast sea of information available the book retains its brevity without oversimplifications, making it of interest to a broad audience."