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"ABSTRAKGenerally, the function of scanner devices is to detect the object two-dimensionally- The signature as the object in this research work, instead of two-dimensional (2-f]) spatial parameter, it has one more parameter is the pressure of the pen to the paper. In order to detect the signature three-dimensionally (3-D), one 2-D array ultrasonic sensors and one pressure sensor are used. This 3-D information can be displayed on monitor (CRT), printed to the printer, and recorded to diskette as a file, respectively. To identified between the already recorded signature data to its standard, the spatial Correlation method is applicator."

"ABSTRAKPembuatan ultrasonic generator telah selesai dilakukan dengan hasil yangcukup menjanjikan untuk daya lebih besar dari 100 Watt dan mampu bekerjadengan baik sampai frekuensi 100 Khz. Ultrasonic generator ini dibuat denganmenggunakan komponen utama mikrokontroler AVR ATTINY2313 sebagaipembangkit sinyal dan switching power amplifier untuk memperkuat daya output.Switching power amplifier dibuat dengan menggunakan mosfet IRF540N yangdisusun membentuk H-Bridge dan dikendalikan oleh H-Bridge driver yaituHIP4081A. Dari hasil ujicoba diperoleh besarnya daya output ditentukan olehbesarnya tegangan VDD yang diberikan rangkaian H-Bridge mosfet dan dutycycle dari gelombang kotak.

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AbstractDeveloping an ultrasonic generator has been completed with resultspromising enough to power more than 100 Watts and able to work well until thefrequency of 100 KHz. Ultrasonic generator is made by using major componentsATTiny2313 AVR microcontroller as a signal generator and switching poweramplifiers to strengthen the power output. Switching power amplifier is madeusing a prepared form IRF540N MOSFET H-Bridge and is controlled by HBridgedrivers is HIP4081A. From the results obtained by testing the poweroutput is determined by the voltage VDD is given a series of H-Bridge MOSFETand duty cycle of square wave."

"Have been made an instrument to dissipate mosquito by using ultrasonic frequency.Instrument dissipation of mosquito represents solution to overcome negative impactwhich generated from usage of chemicals. This matter can be conducted by given theyielded frequency and frequency daunted by mosquito. Result of perception indicatesthat frequency daunted to reside in above frequency able to be heard by human being(ultrasonic frequency). This instrument consist of receiver and transmitter bothcontrolled by microcontroller. Functioning microcontroller to read frequency yieldedby mosquito then release daunted frequency. From result of perception obtained thatmosquito start to react at frequency above 33 kHz."

"New technologies, softwares, and techniques, such as volumetric imaging, enhancement quantification, and fusion imaging, are increasing the diagnostic capabilities of US. The injection of microbubble contrast agents allows better tissue characterization with definitive differentiation between solid and cystic lesions. Contrast-enhanced US improves the characterization of pancreatic tumors, assists in local and liver staging, and can offer savings in both time and money. Acoustic radiation force impulse (ARFI) imaging is a promising new US method to test, without manual compression, the mechanical strain properties of deep tissues. Furthermore, the applications and indications for interventional, endoscopic, and intraoperative US have undergone significant improvement and refinement.This book provides a complete overview of all these technological developments and their impact on the assessment of pancreatic pathologies. Percutaneous, endoscopic, and intraoperative US of the pancreas are discussed in detail, with precise description of findings and with informative imaging (CT and MRI) and pathologic correlations."

"Metode microforming adalah proses pembentukan material dengan deformasi plastis pada parameter mikro. Namun, metode ini memiliki masalah pada skala mikro yang disebut size effect. Untuk mengatasi kesulitan tersebut, terdapat beberapa pendekatan baru, salah satunya menggunakan Ultrasonic Vibration Assisted (UVA) microforming. UVA microforming adalah metode forming dengan memberikan getaran dengan frekuensi tinggi pada benda kerja untuk mengurangi gaya pembentukan, meningkatkan smoothzone, mengurangi kekasaran permukaan, dan meningkatkan akurasi. Untuk menghasilkan getaran, dibutuhkan komponen bolted langevin transducer yang mengubah sinyal listrik menjadi sinyal akustik dalam rentang frekuensi ultrasonik. Performa dan efisiensi transducer sangat bergantung pada desain pada sistem transducer. Oleh karena itu, proses mendesain harus diperhatikan secara detail. Beberapa hal yang perlu diperhatikan dalam mendesain sistem transducer di antaranya perhitungan dimensi komponen, karakteristik getaran, karakteristik pre-stress, dan pemilihan material. Selanjutnya, desain transducer dilakukan simulasi modal dan simulasi harmonic response untuk mengetahui besarnya frekuensi pada getaran longitudinal yang dihasilkan transducer, serta besar displacement transducer setelah diberikan gaya punch. Penelitian ini juga mengukur amplitudo untuk mencari parameter terbaik dalam melakukan proses microforming.......n at a micro parameter. However, this method has a problem at the micro-scale called the size effect. There are several new approaches to overcome these difficulties, one of which is using Ultrasonic Vibration Assisted (UVA) microforming. UVA microforming is a forming method by applying high-frequency vibrations to the workpiece to reduce forming forces, increase smooth zone, reduce surface roughness, and increase accuracy. To produce vibration, a bolted Langevin transducer is needed which converts electrical signals into acoustic signals in the ultrasonic frequency range. The performance and efficiency of the transducer are highly dependent on the design of the transducer system. Therefore, the design process must be considered in detail. Several things that need to be considered in designing a transducer system include the calculation of component dimensions, vibration characteristics, pre-stress characteristics, and material selection. Furthermore, the design of the transducer is carried out with a modal simulation, and a harmonic response simulation to determine the frequency of the longitudinal vibration produced by the transducer, as well as the displacement of the transducer after the punch force is applied. This study also measures the amplitude to find the best parameters for the micro forming process."

"Nondestructive Testing (pengujian tak merusak) merupakan salah satu metode pengevaluasian material dan mengukur besar cacat maupun mendeteksi karakteristik material tanpa merusak material tersebut. Salah satu dari metode pengujian tak merusak adalah dengan menggunakan gelombang ultrasonik. Kecepatan gelombang ultrasonik yang melewati suatu material padat tergantung pada densitas dan propertis elastis dari material tersbut. Pada penelitian ini digunakan gelombang ultrasonik yang dihasilkan oleh alat perambat gelombang ultrasonik. Gelombang ini dirambatkan pada benda uji berupa beton berbentuk kubus (15x15x15) cm_, silinder (_15 cm, t30 cm), balok (15x15x100) cm_ dengan mengkombinasikan nilai water/cement ratio. Water/cement ratio sendiri sangat berpengaruh nilai tekan rancang serta durabilitas beton.Pengujian ultrasonik pada benda uj dilakukan dengan parameter-parameter berupa kuat tekan beton, modulus elastisitas beton, dan pengaruh tulangan, serta keretakan. Perilaku ultrasonik dilihat berdasarkan perubahan cepat rambat gelombang ultrasonik. Dari penelitian didapatkan suatu persamaan yang menyatakan hubungan antara cepat rambat gelombang ultrasonik dengan modulus elastisitas beton. Didapatkan pula bahwa adanya tulangan serta keretakan pada beton akan mempengaruhi pembacaan cepat rambat gelombang ultrasonik.......Nondestructive Testing is one of the material inspection methods to detect and determine mechanical behavior of material without causing any destruction on material tested. Ultrasonic testing is one of well known nondestructive testing method. Velocity of ultrasonic beam passing through solid material depends on density and elastic properties. Different density and elastic properties could make different velocity of ultrasonic wave. In this research, ultrasonic beam propagated by an ultrasonic propagation device with frequency of 54 KHz. This wave propagated in some samples of concrete with shape of cube (15x15x15 cm_), cylindrical (15 cm diameter and 30 cm high), beam (15x15x100 cm_) with combination of water/cement ratio. Water/cement ratio influence the compressive strength and durability of concrete.Parameters used in the ultrasonic testing of concrete samples are compressive strength of concrete, elastic modulus of concrete, influence of reinforcement and crack on concrete samples. All parameters compare with velocity of ultrasonic wave changing. This research obtaining an equation represents the relation between velocity of ultrasonic wave and compressive strength of concrete and the relation between velocity of ultrasonic wave and elastic modulus of concrete. This research also discovered the influence of reinforcement and crack on concrete on velocity of ultrasonic wave."

"ABSTRAKNavigasi otomatis pada drone sedang banyak dikembangkan dari berbagai macam jenis drone dan fungsi otomasinya. Drone yang digunakan pada skripsi ini berupa pesawat dengan empat buah baling-baling atau quadcopter. Skripsi ini membahas tentang sistem otomasi drone dengan menggunakan metode image processing. Tahapan yang pertama pada metode ini adalah feature detection untuk membaca tepi-tepi atau ujung dari suatu benda berdasarkan metode Shi-Tomasi. Data yang didapatk akan diolah pada tahapan optical flow. Tahapan ini dilakukan untuk menentukan jarak atau keberadaan suatu benda yang didasari oleh metode Lucas-Kanade. Namun karena sifatnya yang otomatis, drone tidak dapat terhindar dari kecelakaan jika terjadi kesalahan pembacaan hasil gambar. Untuk mengurangi kesalahan pembacaan, penulis menambahkan sistem sensor ultrasonik. Dengan pembacaan pada jarak tertentu sensor akan membantu pembacaan rintangan yang berada pada lintasan. Pengolahan citra sistem otomasi drone akan diuji coba dengan software OpenCV dan Microsoft Visual Studio. Selanjutnya akan diunduh pada Robot Operating System ROS pada drone. Visual feedback control berbasis pengendali PID digunakan sebagai kendali pengerak drone. Drone yang digunakan pada skripsi ini berupa pesawat dengan empat buah baling-baling atau quadcopter. Disini akan dibahas bagaimana cara kerja antara sensor kamera dan sensor ultrasonik bekerja terintegrasi secara bersamaan agar drone dapat menghindari rintangan secara otomatis.

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ABSTRACTAutomatic navigation on the drone is being developed on these days, from a wide variety of types of drones and its automatic functions. Drones used in this study is an aircraft with four propellers or quadcopter. This research discusses the drone automation system using image processing methods. The first stages in this method is the feature detection to read the edges or corner of an object based on the Shi Tomasi method. Then the data will be processed on the of optical flow phases. This stage will determine the distance or the presence of an object based on the Lucas Kanade method. Furthermore, the object distance is close and there on the track drones will be grouped and considered as obstacles using grouping stage based on the method of K means. But because it is automatic, drones can rsquo t avoid an accident if an error occurs reading the images. To reduce reading errors, the author adds ultrasonic sensor system. With a reading at a certain distance, sensor helps readings obstacles that are on the track. Drone image processing automation system will be tested with OpenCV software and Microsoft Visual Studio. Next the program will be downloaded on the Robot Operating System ROS on the drone. Visual feedback control based PID controllers are used as a control of drones movement. This paper will be discussed how to work the camera sensor and ultrasonic sensor working together so that the drones can avoid obstacles automatically."