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Abstrak :
Uji praklinis radiofarmaka dilakukan untuk menganalisa keamanan serta keefektifan radiofarmaka yang digunakan. Kedua hal tersebut dapat dicapai dengan mengestimasi dosis radiasi internal yang diterima oleh suatu organ. Skema MIRD menyatakan bahwa perhitungan dosis radiasi internal merupakan perkalian antara Time Integrated Activity Coefficients (TIACs) dan S-value dimana nilai TIACs didapatkan dari penggambaran biodistribusi radiofarmaka di dalam tubuh. Hewan percobaan digunakan dalam uji praklinis untuk menggambarkan biodistribusi radiofarmakanya. Hal ini menyebabkan perlunya suatu metode ekstrapolasi untuk memprediksi biodistribusi radiofarmaka di manusia. Melalui penelitian ini, peneliti ingin menganalisa pengaruh penggunaan radiofarmaka terhadap peta performa metode ekstrapolasi. Hasilnya, dibandingkan dengan penelitian Beykan et al, menunjukkan adanya perbedaan peta performa untuk radiofarmaka yang berbeda. Hasil dari penelitian ini juga menunjukkan bahwa organ juga mempengaruhi peta performa metode ekstrapolasi. Oleh karena itu, analisa metode ekstrapolasi perlu dilakukan sebelum uji praklinis suatu radiofarmaka dikarenakan terdapatnya perbedaan peta performa tersebut. ......Preclinical testing of radiopharmaceutical is carried out to analyze the safety and effectiveness of the radiopharmaceutical used. It can be achieved by estimating the dose of internal radiation received by an organ. The MIRD scheme states that the calculation of the internal radiation dose is S-values multiplied by Time Integrated Activity Coefficients (TIACs) whose value is obtained from the depiction of radiopharmaceutical biodistribution in the body Experimental animals are used in preclinical testing to depict radiopharmaceutical’s biodistribution. This results in the need for an extrapolation method to predict radiopharmaceutical biodistribution in humans. Through this study, researchers wanted to analyze the effect of the use of radiopharmaceuticals on the map performance of the extrapolation method. It, compared to the Beykan et al. study, shows the differences in performance maps for different radiopharmaceuticals. Therefore, analysis of extrapolation methods needs to be done before preclinical testing of a radiopharmaceutical because there are differences in performance maps.

Abstrak :
Pengujian fatigue dilakukan pada material komposit fiber glass berjenis woven roving dengan epoxy sebagai matriksnya. Material yang diuji merupakan material yang lolos uji pada serangkaian uji mekanik statis sebelumnya, yaitu WR 200 asimetris epoxy dan WR 400 asimetris-epoxy. Material ini dibuat dengan metode Vacuum Assisted Resin Infusion (VARI) pada suhu ruang. Hasil pengujian fatigue dilanjutkan dengan ekstrapolasi data dari kurva S-N dengan Matlab 7.4 yang berisi curve fitting probabilitas kegagalan untuk memperkirakan masa pakai material. Hasil curve fitting menunjukkan material mempunyai daya tahan di atas siklus 108 untuk pemakaian sekitar 20 tahun. Hasil pengamatan dengan mikroskop optik dan Scanning Electron Microscope (SEM) menunjukkan mekanisme kegagalan material akibat uji fatigue, diawali dengan retaknya matriks, putusnya ikatan permukaan matriks-fiber, diikuti putusnya fiber yang menyebabkan patahnya material. ......Fatigue test was carried out on composite materials with the type of woven roving fiberglass with an epoxy as a matrix. The specification of the fatigue tested materials was selected from previous static mechanical tests, namely WR 200 asymmetric-epoxy and WR 400 asymmetric-epoxy. These materials were produced by using Vacuum Assisted Resin Infusion (VARI) at room temperature. The fatigue test result followed by extrapolation of data from the S-N curve with Matlab 7.4 curve fitting, which contains the probability of failure to estimate the lifetime of the materials. Curve fitting results indicate the materials have a resistance above 108 cycles for the use of about 20 years. The observation with optical microscope and Scanning Electron Microscope (SEM) shows the mechanism of failure due to fatigue test, begins from a matrix cracking, followed by a fiber-matrix interfacial debonding, then a fiber breakage that caused the final fracture.

Abstrak :
This textbook provides a step-by-step approach to numerical methods in engineering modelling. The authors provide a consistent treatment of the topic, from the ground up, to reinforce for students that numerical methods are a set of mathematical modelling tools which allow engineers to represent real-world systems and compute features of these systems with a predictable error rate. Each method presented addresses a specific type of problem, namely root-finding, optimization, integral, derivative, initial value problem, or boundary value problem, and each one encompasses a set of algorithms to solve the problem given some information and to a known error bound. The authors demonstrate that after developing a proper model and understanding of the engineering situation they are working on, engineers can break down a model into a set of specific mathematical problems, and then implement the appropriate numerical methods to solve these problems.