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"ABSTRACT The aim of the paper is to present the influence of selected deflocculants on decreasing the hydromixture viscosity and as a consequence decreasing the wall shear stresses in a flowing medium. Adding deflocculants to improve the conditions encountered in a pipelineduring the hydromixture flow is called chemical processing. The experimental studies presentedin the article were performed for a hydromixture with a mass concentration of 20% and 43%consisting mostly of solids with the averaged diameter equal to 45.5 μm. The measurements wereperformed for varied doses of deflocculants in three proportions in a wide range of shear rates.The results of experiments have confirmed that the influence of the deflocculant on the wallshear stress is complex as there is an opposing phenomenon strongly depending on the dosesof deflocculant samples. The results of the experiments are discussed and major conclusions aredrawn."

"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."

"Studi ini mengkaraterisasi struktur pasangan batu dengan cara mengulas studi kasus yang sudah tersedia terhadap dinding pasangan batu, berfokus pada sifat mode kegagalan dan batas sifat. Data yang tersedua menyatakan bahwa banyak struktur tua yang dibangun dengan materi pasangan batu, terutama yang dibangun sebelum tahuin 1970, tidak dikhususkan untuk menahan pembebanan lateral. Oleh karena itu, struktur tersebut sangat lemah terhadap guncangan gempa bumi. Studi ini mengulas studi yang telah tersedia terhadap struktur pasangan batu dan mengkarakterisasi sesuai dengan data yang ditemukan. Terdapat perubahan tujuan studi saat studi ini berlangsung. Tujuan awal dari studi ini adalah untuk menemukan keuntungan dari memasang beton pada dinding geser pasangan batu, namun, proses eksperimen yang rumit tidak mungkin diselesaikan dalam jangka waktu yang tersedia. Oleh karena itu, tujuan dari studi ini disederhanakan.

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This study explains the characteristic of masonry structure by reviewing the past studies on masonry wall, focusing on its failure modes and limit states. Existing data show that older buildings built with masonry materials, especially those that were built before 1970 were not designed to resist lateral loading, therefore, they are very prone to collapsing if an earthquake hits. This study will review the recent studies related to masonry structure and characterize masonry structure based on the data gathered.

There was a change of aim of study before this project is started. The initial purpose of study was to find the benefit of concrete retrofit on a masonry shear wall, however, due to the limited time and the complicated experiment procedure, the goal of the study must be simplified."

"Pendekatan eksperimen dan model simulasi telah dilakukan untuk mengetahui perilaku partikel halus yang menempel pada lapisan cairan di dinding dalam aliran dua fase gas padat. Polimetil metaklirat dengan diameter 20 um dan 50 um digunakan pada pengukuran ini. Dengan menggunakan sistem pengumpan kontinyu, partikel halus dimasukkan dan dicampur dengan udara di dalam ducting. Eksperimen aliran dua fase dengan gas dan partikel halus padat dalam temperatur ruangan telah dilakukan untuk mengamati efek penempelan partikel yang menempel di dinding yang memiliki lapisan cairan dengan viskositas tinggi. Hasil percobaan menunjukkan bahwa kuantitas partikel melekat tergantung pada kecepatan pengumpanan partikel. Hasil model simulasi juga menunjukkan kecenderungan yang sama. Hubungan laju pengumpanan bermacam-macam partikel dan tingkat penangkapannya dibahas disini."

"Slender shear wall atau dinding geser tipe lansing merupakan dinding geser dengan aspek ratio tinggi terhadap panjang (hw/lw)≥ 2. Menurut SNI 03-2847-2002 dan ACI 318-08, pengurangan kapasitas gaya yang bekerja dibutuhkan dalam mendesain strukutr dinding geser ini. Dari penelitian ini, untuk dinding geser tipe lansing (slender), nilai faktor reduksi kekakuan yang paling berpengaruh adalah F22 dengan persentase kesalahan sebesar 8.18%. Untuk faktor reduksi kekakuan F11 dan F12 memiliki pengaruh yang kecil dengan persentase kesalahan 38.9% dan 32.94%. Penelitian ini dilanjutkan dengan menganalisa penggunaan flat slab pada struktur bangunan.

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Slender shear wall is shear wall with height to length aspect ratio (hw / lw) ≥ 2. According to SNI 03-2847-2002 and ACI 318-08, the reduction of work force capacity is required in designing shear wall structure. From this study, for slender shear wall, the most influential stiffness reduction factor is F22 with a percentage error of 8.18%. Stiffness reduction factor F11 and F12 has little effect, with percentage error of 38.9% and 32.94%. This research was continued by analyzing the use of flat slab in structural building."

"Penelitian ini membahas mengenai perilaku struktur dinding geser beton bertulang dan dinding geser pelat baja dengan analisis statik non-linier pushover akibat beban gempa. Pada penelitian ini ditinjau bangunan 12 lantai pada lokasi gempa di Jakarta, tanah lunak dan dianalisis berdasarkan peraturan SNI 03-1726-201x. Analisis pada struktur dinding geser beton menggunakan SAP2000 dan pada struktur baja menggunakan ETABS v9. Penentuan tingkat kinerja menggunakan metode spektrum kapasitas yang mengacu pada ATC 40. Hasil analisis menunjukkan bahwa model struktur dinding geser pelat baja memiliki kinerja struktur yang lebih baik dibandingkan dengan struktur dinding geser beton bertulang.

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This thesis discussed about behavior of reinforced concrete shear wall and steel plate shear wall using static non-linear pushover analysis due to earthquake load. In this thesis, 12-story building with earthquake location in Jakarta with soft soil is considered and analyzed based on Indonesia Building Code SNI 03-1726-201x. Reinforced concrete shear wall is analyzed by SAP 2000 and steel plate shear wall is analyzed by ETABS v.9. Determination of performance level use spectrum capacity method based on ATC 40. Analysis results show that steel plate shear wall has a better performance level than reinforced concrete shear wall."

"Post-tensioned (PT) flat slab merupakan salah stau sistem struktur yang banyak digunakan di beberapa negara seperti Amerika Serikat, Australia, Afrika Selatan, Thailand, dan India. Dibanding negara lain, penggunaan PT flat slab di Indonesia masih tergolong sedikit, umumnya hanya pada basement. Hal ini dapat diakibatkan oleh struktur flat slab yang rentan terhadap pengaruh gaya lateral, khususnya di Indonesia dengan potensi gempa tinggi. Namun, penggunaan flat slab masih memungkinkan untuk digunakan di daerah dengan potensi gempa tinggi dengan menerapkan Separated Gravity Lateral Resisting System (SGLR System) yaitu desain yang memisahkan antara penahan lateral dan penahan beban gravitasi. Dalam penelitian ini, beban lateral akan dipikul oleh SRPMK dan dinding geser sedangkan flat slab hanya menahan gravtasi. Melalui penelitian ini diharapkan informasi terkait PT flat slab di Indonesia dapat bertamba.

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Post-tensioned (PT) flat slab is one of the structural systems widely used in several countries such as the United States, Australia, South Africa, Thailand, and India. Compared to other countries, the use of PT flat slab in Indonesia is still relatively small, generally only in basements. This can be caused by the flat slab structure which is vulnerable to the influence of lateral forces, especially in Indonesia with high earthquake potential. However, the use of flat slabs is still possible to be used in areas with high earthquake potential by implementing the Separated Gravity Lateral Resisting System (SGLR System), a design that separates lateral resistance and gravity load resistance. In this study, the lateral load will be resist by the special moment resisting frames and shear walls while the flat slab only resists gravity. Through this study, it is hoped that information related to PT flat slabs in Indonesia can be increased."

"ABSTRACTPurpose: Up to 6-7% of patients who have undergone laparoscopic groin hernia repair suffer from chronic pain, depending on various factors; however, the long-term course is unclear. The purpose of this study was to assess the prevalence of chronic pain 1-5 years after laparoscopic groin hernia repair.Methods: The subjects of this nationwide cross-sectional questionnaire study were adults who underwent laparoscopic mesh repair of an inguinal or a femoral hernia. The patients were identified from the Danish Hernia Database, which has a follow-up rate of almost 100%. The prevalence of chronic pain was assessed 1-5 years postoperatively by the validated inguinal pain questionnaire (IPQ).Results: A total of 1383 groins were included in this study, based on a 66% response rate to the questionnaire. The prevalence of pain decreased, especially 3.5 years postoperatively. There were no statistically significant differences when each postoperative year was compared with the second postoperative year. However, the prevalence of chronic pain 3.5-5 years postoperatively was significantly lower (4.4%) than that 1-3.5 years postoperatively (8.1%) (p = 0.014). The prevalence of pain that could not be ignored was still 5-6% in the fifth postoperative year.Conclusions: The prevalence of chronic pain seems to decline 1-5 years after laparoscopic groin hernia repair, with a distinct decrease 3.5 years postoperatively."

"Latar Belakang: Residu radikal bebas pasca perawatan internal bleaching dapat mengganggu proses polimerisasi resin komposit. Akibatnya, terjadi penurunan kekuatan ikatan restorasi. Antioksidan ekstrak teh hijau dapat digunakan untuk menghilangkan radikal bebas pasca bleaching dan meningkatkan shear bond strength resin komposit. Tujuan: mengetahui perbedaan shear bond strength resin komposit pada dentin pasca internal bleaching dengan dan tanpa aplikasi ekstrak teh hijau pada konsentrasi yang berbeda selama 2 menit. Metode: 25 gigi premolar, dipotong dalam arah mesiodistal, dan dibagi menjadi 5 kelompok: Kelompok 1 dentin normal, Kelompok 2 dentin pasca bleaching, Kelompok 3 dentin 2 minggu pasca bleaching, Kelompok 4  dentin pasca bleaching dengan teh hijau 10% 2 menit, dan Kelompok 5 dentin pasca bleaching dengan aplikasi teh hijau 35% 2 menit. Semua kelompok diaplikasikan restorasi resin komposit. Uji shear bond strength menggunakan Universal Testing Machine. Analisis statistik menggunakan one-way ANOVA dan Uji Post Hoc Bonferroni. Hasil: Uji Post Hoc Bonferroni menunjukkan perbedaan bermakna antara kelompok 1 dan 4, kelompok 2 dan 5, serta kelompok 4 dan 5. Kesimpulan: Aplikasi antioksidan ekstrak teh hijau 35% selama 2 menit lebih tinggi dalam meningkatkan shear bond strength resin komposit dibandingkan dengan aplikasi ekstrak teh hijau 10% selama 2 menit pada dentin pasca internal bleaching menggunakan hidrogen peroksida 35%.

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Introduction: Internal bleaching treatment could leave free radicals in the dentinal tubules. It can interfere with the polymerization process of the composite resin. Antioxidants from green tea extract can remove the free radicals after bleaching and increase the shear bond strength of composite resin.

Objective: To determine the shear bond strength of composite resin on dentin after internal bleaching with and without green tea extract application at different concentrations in 2 minutes.

Methods: 25 premolars were cut in mesiodistal direction and divided into five groups: Group 1 normal dentin, Group 2 bleached dentin, Group 3 bleached dentin, Group 4 10% green tea application in 2 minutes, and Group 5 35% green tea application in 2 minutes. All groups were restored with composite resin. All specimens' shear bond strength was tested with the Universal Testing Machine. The data were analyzed with one-way ANOVA and Bonferroni Post Hoc Test.

Results: Post Hoc Bonferroni test showed that there were statistical differences  in groups 1 and 2, groups 1 and 4, groups 2 and 5, and groups 4 and 5.

Conclusion: 35% green tea extract is more effective than 10% green tea extract as an antioxidant for increasing the shear bond strength of composite resin after internal bleaching."

"Penelitian ini membahas mengenai metode desain sistem ganda dari struktur portal - dinding geser beton bertulang akibat beban gempa dan kebutuhan tulangan yang diperlukan untuk masing-masing metode perhitungan. Dalam penentuan sistem ganda sesuai peraturan SNI 03-1726-2002, pada penelitian ini dilakukan tiga metode desain, struktur portal - dinding geser yang berinteraksi, struktur portal dengan boundary element dinding geser, dan struktur portal dengan dengan dinding geser yang di non-aktifkan. Dalam metode portal - dinding geser yang berinteraksi, struktur bangunan di desain berdasarkan analisis dinamik dan analisis statik, tetapi untuk dua metode lainnya dilakukan dengan analisis statik.Pada penelitian ini ditinjau bangunan 8 lantai pada lokasi gempa di Jakarta dengan tanah lunak dianalisis sebagai sistem ganda. Simulasi numerik menunjukkan bahwa pendekatan portal ? dinding geser saling berinteraksi dengan faktor reduksi R = 6,5 (SRPMM) menghasilkan tulangan paling besar dibandingkan dengan dua metode lainnya.

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This thesis discussed about method of design of a reinforced concrete shear wall - frame structure as dual system due to earthquake load and the requirement of rebar for each methods. In determining dual system structure based on SNI 03-1726-2002, some methods of design such as interaction of shear wall - frame structure, frame with boundary element, and frame with deactivated shear wall is considered in this thesis. In interaction of shear wall - frame structure method, building structure was designed based on dynamic and static analysis, however for two other methods static approach was employed.

In this thesis an 8-story building located in Jakarta and built on soft soil was analyzed as dual system. Numerical simulations show that interaction of shear wall ? frame structure approach with reduction factor R = 6,5 (IMRF) results the biggest required rebar compared with other methods."