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"ABSTRAKEksoskeleton secara umum adalah sebuah struktur yang secara anatomis dirancang untuk mengakomodasi gerakan fisik pemakainya dan memberikan kekuatan tambahan. Salah satu tantangan dalam perancangan eksoskeleton adalah dalam menentukan metode kendali yang akan digunakan. Terdapat berbagai macam metode untuk mengendalikan eksoskeleton dan pada penelitian kali ini pengendalian dengan menggunakan sinyal EMG diujicobakan. Tujuan dari penelitian ini adalah untuk mencapai pengendalian optimum menggunakan sinyal EMG. Sinyal EMG adalah tegangan yang muncul ketika otot berkontraksi sehingga gerakan pengguna akan berkorelasi langsung dengan besar RMS sinyal EMG otot tersebut. Nilai RMS dari otot bicep dan tricep digunakan untuk menentukan arah gerak dan kecepatan rotasi motor DC yang menggerakkan eksoskeleton tangan kanan 1 DOF. Perhitungan nilai RMS dilakukan dengan memvariasikan panjang datanya (array length) yang secara teori akan mempengaruhi akurasinya. Selisih diantara kedua nilai RMS tersebut dihitung dan diinterpretasikan sebagai keinginan pengguna untuk melakukan gerakan fleksi atau ekstensi dan akan mengatur arah putaran motor DC. Nilai absolut dari selisih RMS tersebut yang kemudian dikalikan dengan konstanta (gain) digunakan untuk mengatur siklus kerja (duty cycle) sebuah sinyal PWM yang akan mengatur kecepatan putaran motor DC. Pengendalian sebuah sistem dikatakan baik jika settling time-nya kecil. Untuk mendapatkan settling time yang kecil, array length dan gain divariasikan. Pengujian dilakukan dalam dua tahap, yaitu pengujian statis dan dinamis. Hasil pengujian menunjukkan kecenderungan dimana settling time mengecil ketika array length makin pendek dan gain diperbesar. Hal tersebut menunjukkan bahwa pengendalian optimum dapat dicapai dengan memilih nilai array length dan gain yang tepat.

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ABSTRACTExoskeleton in general is a structure that is anatomically designed to be able to accommodate the physical movement of its user and provide additional strength. One of the biggest challenge in designing an exoskeleton is to determine the method of control that will be implemented. There are various control methods that can be used and the use of EMG signal to control a 1 DOF right arm exoskeleton is evaluated in this research. This research aims to achieve optimum control using EMG signal. EMG signal is a variation of voltage that occurs when a muscle contracts hence its strong correlation with the user?s intention of movement. The RMS values of each EMG signal that originates from bicep and tricep muscle are calculated and processed to determine the direction and speed of rotation of a DC motor that actuates the exoskeleton. The RMS calculation is conducted at various array length that will theoretically affect its accuracy. The difference between those two RMS values is then calculated and interpreted as the intention of flexion or extension movement that will control the DC motor rotation direction. The absolute value of the RMS difference multiplied with a gain factor is used to regulate the duty cycle of a PWM signal that is used to control the rotational speed of the DC motor. A good system control is characterized by its settling time, the smaller the better. To achieve the smallest settling time, array length and gain factor is varied. The test was conducted in two stages, static and dynamic test. The test result shows a trend where the settling time decreases when array length is shortened and gain is increased. It shows that optimum control can be achieved by selecting the right array length and gain."

"ABSTRACTPurposesLaparoscopic gastrectomy using ultrasonic devices occasionally causes postoperative pancreatic fistula. Robotic gastrectomy using monopolar scissors may reduce intraoperative injury to the pancreas. We evaluated the safety and feasibility of robotic gastrectomy.MethodsA multicenter prospective study was conducted to evaluate the surgical outcomes of robotic gastrectomy. The primary endpoints were the incidence of intraoperative and postoperative complications and operative mortality.ResultsA total of 115 patients were enrolled. The clinical T stages were T1 in 68 patients and T2 or higher in 47 patients. The types of surgery included distal gastrectomy (n = 72), total gastrectomy (n = 39), and proximal gastrectomy (n = 4). Two patients developed intraoperative complications (1,7%), but no cases required conversion to open surgery. The amylase concentration in drainage fluid was higher in cases with pancreatic compression, especially in those with compression for longer than 20 min. Postoperative complications of Clavien-Dindo grade ≥ II occurred in 11 patients (9,6%). There was no mortality. A multivariate analysis indicated that a high body mass index and pancreatic compression by an assistant for longer than 20 min were independent risk factors for postoperative complications (P = 0,029 and P = 0,010). Conclusions Robotic gastrectomy using monopolar scissors is safe and feasible. Robotic dissection without compression of the pancreas may reduce postoperative complications."

"The development of computer science is now so rapid that we, the readers, increasingly receive technology news about new solutions and applications which very often straddle the border between the real and the virtual worlds. Computer science is also the area in which cognitive science is witnessing a renaissance, because its combination with technical sciences has given birth to a broad scientific discipline called cognitive informatics. And it is this discipline which has become the main theme of this monograph, which is also to serve as a kind of guide to cognitive informatics problems.This book is the result of work on systems for the cognitive analysis and interpretation of various data. The purpose of such an analytical approach is to show that for an indepth analysis of data, the layers of semantics contained in these sets must be taken into account. The interdisciplinary nature of the solutions proposed means that the subject of cognitive systems forming part of cognitive informatics becomes a new challenge for the research and application work carried out."