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"For this paper, we consider the resulting 3-D inversion using inversion modeling, which is motivated by developing theory and the recent application of the Magnetic Resonance Sounding (MRS) technique in detecting and mapping of subsurface groundwater. MRS is a non-invasive method which directly detects the groundwater’s existence from surface measurements. A pulse current, at a proper frequency, is transmitted into a loop. After hydrogen atoms of water molecules in the subsurface are energized by pulses of alternative currents, the magnetic resonance field is produced by the H protons is measured within the same loop. Generally, MRS has two observable factors: initial amplitude and decay time. The aim of three-dimensional inversion is to extract the information, i.e., the value and distribution of two physical parameters of the subsurface conditions: water content and subsurface properties (pore and grain size). Additionally, we present a general formulation for inverting the initial amplitude and decay time of the MRS data to recover a 3-D distribution of groundwater. The forward problem was solved using an integral equation method in the spatial domain. An improved Levenberg-Marquardt strategy was employed to solve the inverse problem. Two synthetic examples are illustrated to determine the basic functionality of the inversion algorithm. The real data results show applicability and relevance in larger-scale field examples."

"Metode NMRS telah digunakan dalam 10 tahun terakhir dengan keberhasilan yang luar biasa dalam berbagai konteks geologi dan eksplorasi airtanah. Metode ini memang mempunyai kemampuan secara langsung untuk mendeteksi keberadaan air melalui eksitasi dari proton hidrogen pada molekul air. Frekuensi dimana proton H terganggu tergantung pada besarnya medan magnet bumi, sementara intensitas eksitasi menentukan kedalaman penyelidikan. Amplitudo medan magnet yang telah dibangkitkan akan dikembalikan lagi oleh lapisan air sebanding dengan porositas lapisan tersebut dan kurva waktu-relaksasi yang konstan berkaitan dengan ukuran pori rata-rata material, artinya erat kaitannya dengan permeabilitas hidrolik. Sebuah kasus lapangan sebagai ilustrasi applikasi NMRS yaitu diambil dari pengukuran di Mauritania. Hasil pengukuran NMRS di daerah kering menunjukkan amplitudo waktu-relaksasi yang rendah (10 A-ms) dan kandungan air 1%. Sedangkan hasil pengukuran NMRS didaerah akuifer menunjukkan amplitude waktu-relaksasi yang cukup besar (270 A-ms) dan kandungan air 12 – 30 %."

"The geomagnetic field is a kind of natural potential field in the Earth. A three-year research program for exploration of this field has been conducted in the Lombok Island-Indonesia, where extreme geomagnetic anomalies with two very strong dipolar structures exist. The research aims to construct a system to collect and concentrate geomagnetic fields, in order to possibly use the concentrated fields for geomagnetic power plants or to integrate the system with a field pick-up unit scheme by means of wireless power transfer. The designed geomagnetic concentrator system has been tested in a self-arranged semi-anechoic chamber with a pair of Helmholtz coils, induced with DC currents to simulate the regional ambient static geomagnetic fields. Several tests have proven the performance of the system in one-dimensional space. This paper presents the results of detailed three-dimensional measurements of static magnetic fields in the semi-anechoic chamber. Static magnetic fields over the entire chamber are drawn in their magnitudes and directions, by interpolating data obtained in regular grids of 50cm × 50cm. In specific areas, where the Helmholtz coil is placed, extra grids of 25cm × 25cm are inserted to sharpen the fields’ depictions. Results show that by inducing 1 A current on each of coils will produce magnetic fields, concentrated over the surrounding area of Helmholtz coil. The intensities of magnetic fields over this area are about 15,000?45,000 nT, which can be used to model the geomagnetic fields of Lombok Island. Using the results of 3D field mapping, it will be possible to get the optimum placement of the geomagnetic concentrator system when it is tested on the chamber."

"Material polikristalin La0,8-xKxBa0,05Sr0,15MnO3 (x = 0 dan 0,05) telah berhasil disintesis menggunakan metode sol-gel. Analisis hasil karakterisasi X-Ray Diffractometer (XRD) menunjukkan bahwa material La0,8-xKxBa0,05Sr0,15MnO3 (x = 0 dan 0,05) yang telah disintesis merupakan material fasa tunggal dengan struktur rhombohedral dan space group R-3c. Hasil karakterisasi XRD juga diperkuat oleh hasil karakterisasi Energy Dispersive X-ray (EDX) dan X-ray Photoelectron Spectroscopy (XPS) yang telah menunjukkan bahwa semua jenis senyawa kimia yang terdapat pada material La0,8-xKxBa0,05Sr0,15MnO3 (x = 0 dan 0,05) merupakan senyawa yang diinginkan. Observasi morfologi menggunakan Scanning Electron Microscope (SEM) menujukkan bahwa substitusi ion potasium berdampak pada terjadinya perbesaran ukuran grain. Karakterisasi Magnetic Properties Measurement System (MPMS) menunjukkan bahwa substitusi ion potasium menyebabkan terjadinya peningkatan temperatur Curie dari 320 K, untuk nilai x = 0, menjadi 335 K, untuk nilai x = 0,05. Peningkatan ini disebabkan karena menguatnya interaksi double-exchange pada sampel dengan nilai x = 0,05. Substitusi ion potasium juga berdampak pada terjadinya peningkatan nilai perubahan entropi magnetik (A𝑆𝑀) dan nilai Low Field Magnetoresistance (LFMR). Nilai −Δ𝑆𝑀 material La0,8-xKxBa0,05Sr0,15MnO3 (x = 0 dan 0,05) meningkat dari 4,21 J/kg K menjadi 4,98 J/kg K pada medan magnet eksternal lima Tesla. Sementara itu, nilai LFMR mengalami peningkatan dari 9% menjadi 14% pada medan magnet eksternal satu Tesla. Berdasarkan hasil analisis perilaku kritis dari material La0,8-xKxBa0,05Sr0,15MnO3 (x = 0 dan 0,05) dapat disimpulkan bahwa substitusi ion potasium mempengaruhi perilaku kritis dari material La0.8-xKxBa0,05Sr0,15MnO3 (x = 0 dan 0,05). Hal ini dibuktikan dengan berubahnya nilai parameter kritis dari material tersebut. Nilai parameter kritis untuk x = 0 adalah 𝛽 = 0,248; 𝛾 = 1,048; dan 𝛿 = 3,342 sedangkan nilai parameter kritis untuk x = 0,05 adalah 𝛽 = 0,226; 𝛾 = 1,183; dan 𝛿 = 4,518. Karakterisasi ESR menunjukkan adanya fasa magnetik yang tidak homogen pada material La0,8-xKxBa0,05Sr0,15MnO3 (x = 0 dan 0,05). Keberadaan fasa magnetik yang tidak homogen ini merupakan bukti terjadinya fenomena phase separation yang berkorelasi kuat terhadap terjadinya peningkatan nilai A𝑆𝑀 dan nilai LFMR.

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Exploration on the magnetic properties of polycrystalline La0.8-xKxBa0.05Sr0.15MnO3 (x = 0 and 0.05) manganite have been reported. The samples have been synthesized using sol-gel method. Powder diffraction analysis shows that both samples crystallized in rhombohedral structure with R-3c space group. Furthermore, rietveld refinement analysis proves that the obtained samples are single phase, without any detectable impurities. This argument is also supported by the characterization result from Energy Dispersive X-ray (EDX) and X-ray Photoelectron Spectroscopy (XPS). Morphological observation using Scanning Electron Microscope (SEM) shows that potassium substitution increases the average grain size of the studied samples. Magnetization measurement with respect to temperature shows that the curie temperature (𝑇𝐶) of sample with potassium ion is larger compared to the undoped sample. The reported 𝑇𝐶 was be 320 and 335 K for x = 0 and x = 0.05, respectively. Detailed inspection upon the magnetocaloric property of the samples shows that potassium substitution increases the magnetic entropy change (A𝑆𝑀) of the sample. The reported −Δ𝑆𝑀 value was 4.21 and 4.98 J/kg K for x = 0 and x = 0.05, respectively. It was found that both samples exhibit a Low Field Magnetoresistance (LFMR) phenomenon at low temperature and low external magnetic field (< 1T). Moreover, potassium substitution increases the estimated LFMR value from 9 to 14% for x = 0 and x = 0.05, respectively. The analysis on the critical behavior of both samples shows that potassium substitution affects the critical behavior of the studied samples. This is shown by the different critical parameters for each sample. The reported critical parameter for x = 0 are 𝛽 = 0.248; 𝛾 = 1.048; 𝛿 = 3.342 and the critical parameters for x = 0.05 are 𝛽 = 0.226; 𝛾 = 1.183; and 𝛿 = 4.518. Electron Spin Resonance (ESR) characterization reveals that there is a presence of magnetic inhomogeneity inside both samples. The presence of magnetic inhomogeneity suggests that both samples exhibit a phase separation phenomenon. This phenomenon is believed to greatly influence the increase of A𝑆𝑀 and LFMR value in the studied samples."

"Kerangka kerja konseptual mengenai praktik Audit Internal telah dikeluarkan oleh The Institute of Internal Auditor dimana Auditor Internal harus memiliki pengetahuan yang memadai untuk mengevaluasi risiko fraud dan cara organisasi mengelola risiko tersebut. Sehingga Audit Internal turut mempunyai peran dalam mencegah dan mendeteksi fraud. Walaupun pencegahan dan pendeteksian fraud merupakan tanggung jawab manajemen perusahaan, Auditor Internal diharapkan dapat melakukan dua hal tersebut sebagai bagian dari pelaksanaan tugas manajemen.Penelitian ini mengkaji penerapan program pencegahan dan pendeteksian fraud serta peran Audit Internal dalam mendukung efektivitas Fraud Management Program yang ada di perusahaan dengan metode penelitian kualitatif deskriptif dan pendekatan studi kasus. Observasi, wawancara dan studi dokumentasi digunakan dalam proses pengumpulan data.Hasil penelitian ini menjelaskan bahwa manajemen telah memiliki struktur pengendalian yang cukup baik dalam pencegahan dan pendeteksian fraud dan Audit Internal sudah berperan secara menyeluruh dalam semua komponen pembentuk effective Fraud Management Program.

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Internal Audits Professional Practices Framework has been issued by The Institute of Internal Auditors, stated that Internal Auditors must have sufficient knowledge to evaluate the risk of fraud and the manner in which it is managed by the organization. Thus, Internal Audit also has a role in fraud prevention and detection. Although the responsibility in fraud prevention and detection addressed to the management, Internal Audit is expected to conduct those activities as part of the managements task force.

This study examines the application of fraud prevention and detection program and the role of Internal Audit in improving the effectiveness of Fraud Management Program in place by using qualitative descriptive research method and using case study approach. Observation, interview and documentation studies are used in data collection method.

As result explains that currently the management already has sufficient control structure in preventing and detecting fraud and Audit Internal has played a comprehensive role in all components that forming the effective Fraud Management Program."

"Sistem kendali merupakan hal penting di dalam perancangan sebuah alat bantu berjalan untuk pasien pasca stroke yang mengalami hemiparetik pada kakinya. Sistem kendali yang baik harus mampu mengetahui keinginan bergerak atau berjalan dari manusia dan menerjemahkan keinginan tersebut menjadi sebuah gerakan yang alami melalui alat bantu berjalan yang umumnya digerakkan oleh sebuah perangkat DC motor. Sudah banyak penelitian yang telah dilakukan untuk melakukan deteksi terhadap keinginan manusia untuk bergerak atau berjalan melalui berbagai macam sensor yang dipasang pada otot-otot yang terkait. Fokus dalam penelitian ini adalah melakukan deteksi gaya berjalan melalui sinyal elektromiografi yang diperoleh dengan menggunakan sensor-sensor EMG yang dipasangkan pada permukaan 12 otot yang sangat berkaitan dengan gerakan atau gaya berjalan pada manusia. Adapun 12 otot ini terdiri dari 2 otot bahu yaitu Deltoid Anterior (DA) dan Deltoid Posterior (DP), dan 10 otot kaki yang terdiri dari Rectus Femoris (RF), Biceps Femoris (BF), Vastus Medialis (VM), Vastus Lateralis (VL), Tibialis Anterior (TA), Medial Gastrocnemius (MG), Soleus (S), Gluteus Maximus (GMax), Semitendinosus (ST), dan Peroneus Longus (PL). Sinyal elektromiografi dari 12 otot tersebut direkam dari 2 pasien sehat yang tidak mengalami gangguan berjalan, terdiri dari 1 orang pria dan 1 orang wanita. Sinyal tersebut kemudian diproses melalui aplikasi Matlab untuk dilakukan proses klasifikasi dengan menggunakan teknik Artificial Neural Network (ANN). Di samping itu, metode machine learning juga dilakukan yaitu dengan teknik Linear Discriminant Analysis (LDA), Support Vector Machine (SVM) dan K-Nearest Neighbor (KNN), yang bertujuan untuk mendapatkan perbandingan berbagai teknik tersebut agar didapatkan hasil dengan tingkat akurasi terbaik di dalam melakukan deteksi gaya berjalan yang dibedakan menjadi 3 yaitu: berjalan normal, naik tangga dan turun tangga. Hasil terbaik yang diperoleh dari penelitian ini dengan menggunakan algoritma ANN yang mampu menghasilkan prediksi sempurna dengan tingkat akurasi 100%, kemudian tingkat akurasi terbaik yang diperoleh dengan metode machine learning masing-masing untuk algoritma SVM adalah sebesar 99.2%, algoritma KNN sebesar 98.8% dan algoritma LDA sebesar 97.2% yang semuanaya diperoleh dari dataset kombinasi sinyal EMG otot bahu dan kaki. Hasil ini sangatlah penting di dalam penelitian yang akan dilakukan di kemudian hari dalam merancang sebuah sistem kendali yang mampu mengenali keinginan bergerak atau berjalan manusia baik saat berjalan normal maupun ketika hendak naik atau turun tangga sehingga alat bantu berjalan yang dihasilkan dapat digunakan dengan nyaman dan aman oleh pemakainya.

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Control strategy is a fundamental role and very important part to create a walking assistive device for patients after stroke with a hemiparetic leg. A good control strategy must have the ability to predict the human motion or walking intention and naturally deliver force by the walking assistive device thereafter. This force is usually generated by the electric actuator using direct-drive motor. Recently, many studies have addressed and put more interest in predicting the human motion intention through various sensors which put on the surface of related skeletal muscles. This study focuses on gait event detection using electromyography signals from 12 muscles comprise of 2 shoulder muscles those are Deltoid Anterior (DA) and Deltoid Posterior (DP) and 10 lower limb muscles those are Rectus Femoris (RF), Biceps Femoris (BF), Vastus Medialis (VM), Vastus Lateralis (VL), Tibialis Anterior (TA), Medial Gastrocnemius (MG), Soleus (S), Gluteus Maximus (GMax), Semitendinosus (ST), and Peroneus Longus (PL). The EMG signals are recorded unilaterally using surface EMG sensor from 2 healthy subjects without walking disorder, consist of 1 male and 1 female. The signals are processed on Matlab platform subsequently for classification process using Artificial Neural Network (ANN) technique. Besides, the machine learning methods are also used in this research i.e. Linear Discriminant Analysis (LDA), Support Vector Machine (SVM) and K-Nearest Neighbor (KNN). The purpose of using several methods is to output the comparison with highest accuracy result in predicting the gait events which are divided into 3 types: normal walking, stair ascent, and stair descent. The best outcome along this research is generated from ANN algorithm which could steadily predict without any error with accuracy rate 100%. Furthermore, the best results from machine learning method are 99.2% using SVM algorithm, 98.8% using KNN algorithm and 97.2% using LDA algorithm. All those performances are resulted from datasets with combination between EMG signals from shoulder and lower limb muscles. This achievement becomes a significant factor for the future studies to design a control strategy with good human-robot interaction that can recognize the human motion intention in each different gait event to contrive comfort and safety walking assistive device for the wearer. "

"The idea of using the enormous potential of magnetic resonance imaging (MRI) not only for diagnostic but also for interventional purposes may seem obvious, but it took major efforts by engineers, physicists, and clinicians to come up with dedicated interventional techniques and scanners, and improvements are still ongoing. Since the inception of interventional MRI in the mid-1990s, the numbers of settings, techniques, and clinical applications have increased dramatically. This state of the art book covers all aspects of interventional MRI. The more technical contributions offer an overview of the fundamental ideas and concepts and present the available instrumentation. The richly illustrated clinical contributions, ranging from MRI-guided biopsies to completely MRI-controlled therapies in various body regions, provide detailed information on established and emerging applications and identify future trends and challenges."