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"Antenna footprint indicates the shape and size of the area illuminated by the antenna on the ground surface or subsurface. For GPR it is important as it determines the cross-range resolution of the radar. In this paper we demontrate that an array antenna comprising a number of rolled-dipole elements can produce a variable footprint by activating certain elements and deactivating the others. In this way the size of the array's footprint can be adjusted to remain comparable with the cross section of various targets which in turn minimizes clutter and improving the GPR performance . This paper presents FDTD simulation results and preliminary experimental result of the proposed antenna."

"Very few people are aware of the significant negative impact that cluttering- a communication disorder which affects a person's ability to speak in a clear, concise and fluent manner- can have on one's life educationally, socially and vocationally. Although different from stuttering, it is often related to this more well-known disorder. This book treats cluttering as a serious communication disorder in its own right, providing an in-depth examination of the critical factors surrounding its assessment, treatment and research. Using evidence-based data as well as information regarding the assessment and treatment of cluttering within the field of speech-language pathology, the volume includes the latest research findings and work from leading worldwide cluttering experts. Current viewpoints regarding cluttering, along with substantiated evidence are provided. Research findings are presented regarding the nature and neurology of cluttering. A range of successful assessment and treatment methodologies are described in the context of disorders which may co-occur with cluttering, such as autism spectrum disorders, learning disabilities, Down Syndrome and stuttering. Future directions with regards to the definition, teaching and researching of cluttering are also addressed. Students, faculty members, researchers and clinicians in the field of speech pathology will find this book an essential and unique source of information on cluttering."

"Cijeruk adalah salah satu daerah strategis yang akan digunakan untuk pariwisata karena lingkungannya masih asri dan memiliki akses yang mudah dari Jakarta dengan adanya ruas Jalan Tol Bogor-Ciawi-Sukabumi, tol Ciawi-Cigombong. Sayangnya, Cijeruk memiliki potensi gerakan tanah longsor sedang hingga tinggi sejak awal 2019. Oleh karena itu, perencanaan pembagunan yang baik diperlukan untuk mengurangi risiko bencana dari gerakan tanah longsor. Salah satu upaya yang bisa dilakukan dengan membuat fondasi bangunan hingga ke batuan dasar. Metode yang digunakan untuk menentukan kedalaman batuan dasar adalah Ground Penetrating Radar (GPR). Alat GPR yang digunakan dalam penelitian ini memiliki frekuensi 25 MHz, penetrasi gelombang mencapai kedalaman75 m. Dari penelitian ini, peneliti memperoleh gambaran bawah permukaan secara 2 dimensi, kedalaman batuan dasar antara 10-20 m. Hasil ini dapat digunakan sebagai bahan pertimbangan untuk fondasi bangunan tahan longsor.

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Cijeruk is one of the strategic locations to be used for tourism because the environment is still beautiful and it has easy access from Jakarta with the existence of the Section 1 toll road Bogor-Ciawi-Sukabumi, Ciawi-Cigombong toll road. Unfortunately, Cijeruk has medium to high potential for landslide movements in early 2019. Therefore, good development planning is needed to reduce the disaster risk of landslide movements. One geophysical efforts that can be done by making the foundation of the building down to the bedrock. The method used to determine the depth of the bedrock is Ground Penetrating Radar (GPR). GPR tool used in this research has frequency range 25 MHz, depth penetration 75 m. From this research, we obtained 2D subsurface visualization, bedrock detected at depth 10-20 m. This result could be used as a reference for the foundation of landslide-resistant buildings."

"Provinsi Sulawesi Selatan merupakan provinsi yang sering mengalami banjir. Berdasarkan historis, tahun 2019 merupakan fenomena banjir terparah yang pernah terjadi. Oleh karena itu kini pemerintah sedang mengupayakan peningkatkan pembangunan infrastruktur untuk pengendalian banjir termasuk di Provinsi Sulawesi Selatan. Dalam pembangunan infrastruktur diperlukan perencanaan yang matang, salah satunya dengan mengetahui kondisi bawah permukaan. Dalam penelitian ini dilakukan pengukuran melalui kombinasi metode Airborne Ground Penetrating Radar dan Resistivitas. Tujuannya untuk mengidentifikasi perlapisan litologi bawah permukaan yang berfokus pada kompleksitas struktur dan persebaran zona bedrock sebagai informasi pendahuluan dalam perencanaan pembangunan infrastruktur di lingkungan fluvial untuk pengendalian banjir Luwu Utara, Sulawesi Selatan. Dari hasil pengolahan dan interpretasi kedua metode, menunjukkan lokasi penelitian memiliki litologi yang terdiri dari material sedimen (clay dan silt; sand dan gravel) dan batuan bedrock (granite), dengan adanya indikasi zona lemah pada lokasi yang tersusun dari clay dan silt serta sand dan gravel bersaturasi tinggi. Terkait persebaran zona bedrock, menunjukkan semakin dangkal ke arah selatan dari badan sungai dan sebaliknya.

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Floods frequently occur in the province of South Sulawesi. The greatest flood event ever according to historical records happened in 2019. In order to better prevent flooding, the government is now working to create more infrastructure, including in the province of South Sulawesi. Careful planning is necessary for infrastructure construction, and one aspect of such preparation is gathering data on subsurface conditions. In this study, measurements were conducted by combining the methods of resistivity and airborne ground penetrating radar. The aim is to identify subsurface lithological layers that focus on the structural complexity and distribution of bedrock zones as preliminary information in infrastructure development planning in a fluvial environment for flood control in North Luwu, South Sulawesi. From the results of processing and interpretation, it shows that the research location made up of sedimentary material (clay and silt; sand and gravel) and bedrock (granite), with an indication of a weak zone at the location made up of clay and silt as well as highly saturated sand and gravel. And the bedrock zone's distribution demonstrates that it becomes shallower to the south of the river body and vice versa.

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"Ground-penetrating radar has come to public attention in recent criminal investigations, but has actually been a developing and maturing remote sensing field for some time. In the light of recent expansion of the technique to a wide range of applications, the need for an up-to-date reference has become pressing. This fully revised and expanded edition of the best-selling Surface-Penetrating Radar (IEE, 1996) presents, for the non-specialist user or engineer, all the key elements of this technique, which span several disciplines including electromagnetics, geophysics and signal processing. The book will help users to assess the potential of the technique and currently available technology and to apply them effectively."

"Ground Penetrating Radar (GPR) adalah sistem radar yang pulsanya diarahkan kebawah permukaan tanah. Konfigurasi common offset dengan frekuensi 200 MHztelah digunakan untuk memperoleh kecepatan gelombang radar dalam mediumpasir. Telah dilakukan penurunan waktu tempuh dari perekaman data GPR untukmendeteksi anomali berupa penampang melintang benda silinder. Model lapanganlokasi akuisisi data terdiri dari sebuah pipa besi dan dua buah pipa PVC denganposisi kedalaman 1 meter. Waktu tempuh ini kemudian digunakan untukmenentukan kecepatan medium, kedalaman, dan jari-jari silinder denganmenggunakan teknik inversi Marquardt – Levenberg. Hasil inversi dari datalapangan memperlihatkan bahwa metode tersebut mampu untuk memperkirakankecepatan dan struktur medium dengan anomali penampang melintang bendasilinder sehingga diharapkan mampu untuk mengestimasi kedalaman dan jari-jarisilinder."

"Metode Ground Penetrating Radar (GPR) telah diaplikasikan untuk memetakan batuan dasar sungai di Kalimantan. Prinsip kerja metode ini didasarkan pada perbedaan konstanta dielektrik pada batas lapisan. Data yang digunakan terdiri dari 4 line. Data ini diolah dengan menggunakan software radan. Hasil pengolahan data ini digunakan untuk interpretasi zona-zona yang berhubungan dengan dasar sungai, lapisan alluvial, dan bedrock. Didukung oleh data geologi regional, hasil pengukuran GPR menunjukkan bahwa daerah penelitian didominasi oleh batuan vulkanik yang merupakan batuan dasar sungai. Berdasarkan hasil interpretasi, kedalaman masing-masing lapisan ini bervariasi pada tiap-tiap line.

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The Ground Penetrating Radar (GPR) method has been applied for river bedrock mapping. This method work principle is based on different of dielectric constant in reflector. The data that used consist of 4 line. The data was processed by using radan software. Data processing result is used for zones interpretation that relating with river floor, alluvial layer, and bedrock. Supported with regional geology data, result from GPR data show that the research site is dominated by volcanic rock which is river bedrock. Based on result of interpretation the depth of each layer is vary in each line."

" Inspeksi beton perlu dilakukan untuk mencegah terjadinya kegagalan struktur pada beton. Ground-penetrating radar (GPR) menjadi salah satu alat yang digunakan untuk mendeteksi keberadaan tulangan baja di dalam beton, dimana GPR mampu mendeteksi dan mencitrakan obyek yang berada di dalam beton tanpa diperlukannya tindakan invasif. Pada skripsi ini telah dilakukan rancang bangun GPR untuk aplikasi inspeksi beton sedalam 1 meter. Sistem GPR dirancang menggunakan frequency modulated continuous wave (FMCW) dan bekerja pada pita frekuensi ISM 2,4 - 2,5 GHz. Sistem FMCW GPR yang dibuat menggunakan LimeSDR Mini sebagai modul transceiver, antena Vivaldi elemen tunggal sebagai antena TX, antena susun rectangular patch terintegrasi unequal Wilkinson power divider sebagai antena RX tipe pertama dan antena susun Vivaldi sebagai antena RX tipe kedua. Kedua antena susun menggunakan metode Dolph-Chebyshev weighting.Pengujian dilakukan pada setiap komponen sistem FMCW GPR terlebih dahulu sebelum pengujian sistem seutuhnya. Pengukuran antena TX menunjukkan bahwa antena mampu bekerja pada frekuensi 2,4 – 2,5 GHz, memiliki H-plane beamwidth sebesar 105o, gain sebesar 5,12 dB. Pengukuran antena RX tipe pertama menunjukkan bahwa antena mampu bekerja pada frekuensi 2,356 – 2,589 GHz, memiliki H-plane beamwidth sebesar 26o, sidelobe level sebesar -17,451 dB, front-to-back ratio sebesar -20,22 dB, dan gain sebesar 5,12 dB. Pengukuran antena RX tipe kedua menunjukkan bahwa antena mampu bekerja pada frekuensi 2,4 – 2,5 GHz, memiliki H-plane beamwidth sebesar 25o, sidelobe level sebesar -13,939 dB, front-to-back ratio sebesar -8,208 dB, dan gain sebesar 10,096 dB. Pengukuran low noise amplifier menunjukkan bahwa LNA memiliki gain dengan rentang 11,85 – 13,1 dB pada frekuensi 2,3 – 2,7 GHz. Pengukuran kabel coaxial menunjukkan bahwa kabel memiliki loss dengan rentang -0,49 dB hingga -0,66 dB. Semua komponen dapat bekerja sesuai spesifikasi yang telah ditentukan.Pengujian sistem FMCW GPR dilakukan menggunakan beton bertulang ketebalan 30 cm. Target deteksi berupa besi dalam beton. Hasil pengujian diolah menggunakan perangkat lunak MATLAB untuk kemudian diperoleh citra melintang dari beton. Hasil citra yang diperoleh menunjukkan perbedaan permukaan dengan isi beton uji. Besarnya pantulan dibedakan dengan warna. Spektrum merah menandakan pantulan terbesar dengan nilai maksimum -650 dB, sedangkan spektrum biru menandakan pantulan daya terkecil dengan nilai maksimum -690 dB.

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Concrete structure needs inspection to prevent structural failures. In concrete inspection activity, ground-penetrating radar (GPR) is one of the tools used to detect the location of steel reinforcement in concrete without the need for invasive action. In this research, GPR was designed for concrete inspection applications with concrete thickness of 1 meter. GPR for concrete inspection application is designed using frequency modulated continuous wave (FMCW) and works on ISM bands with a frequency range of 2.4 – 2.5 GHz. FMCW GPR system is designed using LimeSDR Mini as transceiver module, rectangular patch antenna array integrated with unequal Wilkinson power divider as first type RX antenna, Vivaldi antenna array as second type RX antenna, and single element Vivaldi antenna as TX antenna.

Tests are performed on each component of the FMCW GPR. Measurement of TX antenna shows the antenna works at a frequency range of 2.4 – 2.5 GHz, has a H-plane beamwidth of 105o and a gain of 5.12 dB. Measurement of first type RX antenna shows the antenna works at frequency range of 2.356 – 2.589 GHz, has a H-plane beamwidth of 26o, sidelobe level of -17.451 dB, front-to-back ratio of -20.22, and gain of 5.12 dB. Measurement of second type RX antenna shows the antenna works at frequency range of 2.4 – 2.52 GHz, has a H-plane beamwidth of 25o, sidelobe level of –13.939 dB, front-to- back ratio of -8.208, and gain of 10.096 dB. Measurement of low noise amplifier shows that the LNA has a gain range of 11.85 – 13.1 dB in the frequency range of 2.3 – 2.7 GHz. Measurement of coaxial cable shows that the cable has loss range of 0.49 – 0.66 dB. All components can be used according to predetermined specifications.

FMCW GPR system test were conducted using reinforced concrete with 30 cm thickness and steel bar inside the concrete as target. The test results were processed using MATLAB software to get transection image of the concrete. Image results show that it can differentiate between the concrete surface and inner concrete. The magnitude of radar wave reflection is distinguished by color. The red spectrum indicates the largest reflection with a maximum value of -650 dB, while the blue spectrum indicates the smallest reflection of power with a maximum value of -690 dB."