Hasil Pencarian  ::  Simpan CSV :: Kembali

"Tesis ini membahas tentang Pengendali Logika Fuzzy sistem Thermal Mixing. Salah satu contoh proses thermal mixing yang cukup sederhana dan mewakili adalah Proses Pencampuran Air Panas dan Air Dingin. Sistem pencampuran air panas dan air dingin ini terdiri atas sebuah tangki dengan dua buah pipa saluran masukan dan sebuah saluran keluaran. Level dan temperatur air akan diukur dengan menggunakan tranduser.Sistem pencampuran air panas dan air dingin ini merupakan sistem yang multivariabel dengan empat masukan dan dua keluaran. Dari pemodelan yang diperoleh dapat dilihat bahwa sistem pencampuran ini merupakan sistem non linier. Sifat non linier sistem ini merupakan suatu kendala yang harus dikendalikan untuk mendapatkan hasil yang diinginkan yaitu temperatur dan level air tertentu.Konfigurasi sistem yang digunakan pada pengujian ini adalah maksimum tinggi air dalam tangki 2 m, luas alas tangki 2 m2, luas penampang pipa air 0,05 m2, tinggi level air awal 1 m, suhu air awal dalam tangki 27°C.Untuk melihat tanggapan sistem pengendalian proses pencampuran air panas dan air dingin dengan menggunakan pengendali logika fuzzy maka harus dilakukan berbagai pengujian dengan berbagai macam kondisi. Pengujian ini dilakukan dengan menggunakan fasilitas Simulink versi 4 pada program Matlab versi 6.0.0.88 Release 12.

---

This thesis studies a fuzzy logic controller to the process of thermal mixing. An example of a simple thermal mixing process that represent it was a cold and hot water mixing process. The cold and hot water mixing system consist of a tank which connected to two water pipe inputs and a water pipe output. Water level and temperature were measured with transducers.

The cold and hot water mixing process was a multivariable system with four inputs and two outputs. From mathematical models, the mixing system is a non linear system. The non linearity of this system is the constraint that has to be controlled to achieve the temperature and level set points.

The system configuration used in the examination are 2 m of maximum water level in tank, base area of tank is 2 m2, cross section area of outlet pipe is 0.05 m2 initial water level is 1 m and initial water temperature is 27°C.

The responds system of the mixing process control using fuzzy logic controller was tested in some variants conditions. The tests were simulations using the Simulink version 4 facility in Matlab version 6.0.0.88 release 12 program."

"Kondisi lingkungan dapat memberikan efek yang sangat besar dalam bentuk kegagalan komposit karbon/epoksi. Kondisi lingkungan menjadi perhatian dalam dunia penerbangan karena dapat mempengaruhi kekuatan mekanik dan sifat termal dari material yang dijadikan bahan penyusun struktur pesawat. Penelitian ini dilakukan untuk mengetahui pengaruh kondisi lingkungan, khususnya kemampuan penyerapan kadar air, kekuatan mekanik, sifat termal, dan jenis kerusakan dari komposit karbon/epoksi unidirectional. Komposit ini dibuat dengan metode dry hand lay-up. Untuk mengetahui hal tersebut, komposit karbon diberikan kondisi lingkungan yang berbeda, yaitu keadaan tanpa perendaman, direndam dalam air panas, dan air laut dalam waktu tertentu. Dari hasil pengamatan penyerapan kadar air dari, didapatkan kandungan kadar air maksimum yang terserap ke dalam komposit karbon/epoksi dalam lingkungan air panas 0,89 selama 1100 jam dan air laut 0,57 selama 1200 jam perendaman. Uji mekanik short-beam shear menunjukkan persentase penurunan nilai kekuatan antarlamina dari hasil uji mekanik pada keadaan air panas dan air laut berturut-turut sebesar 9,66 dan 0,92 dibandingkan dengan bahan tanpa perendaman. Suhu transisi gelas relatif sama dari tiap kondisi lingkungan. Hasil pengamatan mikroskop optik dan Scanning Electron Microscope tidak memperlihatkan perbedaan yang berarti dari ketiga komposit. Jadi material komposit karbon/epoksi unidirectional tidak mengalami perubahan berarti pada sifat termal dan kerusakan permukaan akibat pengaruh air panas dan air laut.

---

Environmental conditions can result a profound effect in a forms of carbon epoxy composite failures. Environmental conditions are one of the main considerations in the aerospace industry as they can affect the mechanical strength and thermal properties of the materials that be used as aircraft structures. This study was aimed to determine the effect of environmental conditions, especially the moisture absorption, mechanical strength, thermal properties, and types of damage of unidirectional carbon epoxy composites. The composites were fabricated by a dry hand lay up process. The composites were conditioned in different environment which were normal condition or without immersion, soaked in both hot water, and seawater within a certain time. The maximum moisture content that was absorbed in the composites was 0.89 for 1100 hours in hot water and was 0.57 in seawater for 1200 hours of immersion. Furthermore, short beam shear test results showed that the interlaminate strength values reduced 9.66 and 0.92 in hot water and sea water conditions respectively compared to composites in normal condition. The glass transition temperature of hot water and sea water conditioned materials were relatively similar compared to materials in normal condition. According to optical microscope and Scanning Electron Microscope observations, there was no visible difference on the surface of three materials. Thus, the thermal property and the appearance of the unidirectional carbon epoxy composites did not change in hot water and sea water."

"This book presents cutting-edge work on the energy efficiency and environmental sustainability of buildings, examining EU policies, regulations and technologies for complex systems such as passive buildings, sustainable buildings and, as part of the Energy Performance of Building Directive (EPBD), nearly Zero Energy Buildings (nZEB) requirements. It explores a wide range of topics, including indoor environment requirements, building physics, in-situ experiments to determine the thermal properties of buildings, nZEB requirements, building service technology, and methods of evaluating energy efficiency and environmental impacts. It also provides an overview of the best available technologies for nZEB, including those for the rational use of energy, utilization of renewable energy sources, EPBD systems and calculation methods. This book is a valuable resource for students, researchers and practitioners of urban planning, and architecture, civil and mechanical engineering."