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Abstrak :
This multi-contributed volume provides a practical, applications-focused introduction to nonlinear acoustical techniques for nondestructive evaluation. Compared to linear techniques, nonlinear acoustical/ultrasonic techniques are much more sensitive to micro-cracks and other types of small distributed damages. Most materials and structures exhibit nonlinear behavior due to the formation of dislocation and micro-cracks from fatigue or other types of repetitive loadings well before detectable macro-cracks are formed. Nondestructive evaluation (NDE) tools that have been developed based on nonlinear acoustical techniques are capable of providing early warnings about the possibility of structural failure before detectable macro-cracks are formed. This book presents the full range of nonlinear acoustical techniques used today for NDE. The expert chapters cover both theoretical and experimental aspects, but always with an eye towards applications. Unlike other titles currently available, which treat nonlinearity as a physics problem and focus on different analytical derivations, the present volume emphasizes NDE applications over detailed analytical derivations. The introductory chapter presents the fundamentals in a manner accessible to anyone with an undergraduate degree in Engineering or Physics and equips the reader with all of the necessary background to understand the remaining chapters. This self-contained volume will be a valuable reference to graduate students through practising researchers in Engineering, Materials Science, and Physics.

Abstrak :
Sedikitnya penelitian tentang bata merah pejal (Solid Clay Brick) di Indonesia disebabkan oleh tingginya faktor kesulitan dalam menentukan parameter mekanik bata tersebut. Penelitian kali ini dilakukan untuk mencari parameter mekanik bata pejal Cikarang yaitu; Modulus Elastisitas Dinamis, Modulus Geser Dinamis, dan Nisbah Poisson dengan menggunakan metode Non Destructive Test. Alat non destructive yang digunakan adalah Ultra Sonic Scope dan Young's Modulus Rigidity Meter yang terdapat di Laboratorium Struktur Jurusan Sipil Fakultas Teknik Universitas Indonesia. Kedua alat ini sangat mengandalkan kondisi fisik dari benda uji guna mendapatkan hasil yang akurat. Kehomogenan dan tingkat kepadatan menjadi faktor penentu utama. Bata pejal Cikarang memiliki sifat yang tidak homogen. Pengaruh kulit padi (sekam), sebagai bahan campuran sedikit banyak membawa andil terjadinya lubang di bagian dalam bata saat dibakar. Dari pengujian yang dilakukan dengan menggunakan Ultra Sonic Scope didapat nilai-nilai parameter mekanik yang cukup logis dibandingkan dengan nilai referensi yang ada. Dari nilai rata-rata kasarnya dihasilkan Nisbah Poisson sebesar 0,17, nilai Modulus Elastisitas Dinamis , Eo = 49.382 kg/cm_ dan nilai Modulus Geser Dinamis, GD = 21.250 kg/cm_. Jika digunakan Young's Modulus Rigidity Meter dihasilkan nilai rata-rata kasar Nisbah Poisson sebesar 0,535, nilai Modulus Elastisitas Dinamis , ED = 34.168 kg/cm_ dan nilai Modulus Geser Dinamis, GD = 1.214 kg/cm_. Sedangkan dari referensi diketahui bahwa nilai Nisbah Poissonnya mencapai 0,20, nilai Modulus Elastisitas Dinamis , ED = 100.000 - 240.000 kg/cm_ dan nilai Modulus Geser Dinamis, GD = 41.667 - 100.000 kg/cm_. Dilihat dari hasil yang didapatkan, maka pada contoh kasus bata pejal Cikarang ini, alat Ultra Sonic Scope lebih akurat dibanding dengan Young's Modulus Rigidity Meter seningga nilai yang didapat dari Young's Modulus Rigidity Meter untuk bata pejal ini tidak dapat digunakan, Satu hal yang dapat digunakan sebagai hipotesis awal adalah meningkatnya kuat tekan bata sebanding dengan semakin besarnya cepat rambat gelombang Ultra Sonic Scope pada bata. Selain itu, melalui penggunaan Young's Modulus Rigidity Meter yang memang begitu peka, dapat disimpulkan bahwa ada ketidakhomogenan pada sebagian besar bata yang diuji. Dan dilihat dari berbedanya nilai parameter mekanik dari masing-masing bata dapat dikatakan bahwa pembuatan bata pejal Cikarang belum terstandard.

Abstrak :
Perkembangan teknologi alat investigasi mutu struktur bangunan beton terus berkembang digunakan untuk melakukan pengujian dalam mengevaluasi tulangan dan ketebalan selimut beton dalam beton bertulang tanpa merusak struktur (Non Destructive Test). Alat yang umum digunakan yaitu Profometer dan Ultraportable Ground Penetrating Radar. Dengan perbedaan prinsip kerja, dalam penelitian ini dilakukan studi evaluasi ketebalan selimut beton, identifikasi tulangan dan material isolator, dengan membandingkan hasil pengujian alat profometer, ultraportable ground penetrating radar terhadap struktur pelat lantai ukuran 2x2 m, Hasil pengujian ground penetrating radar dapat divisualisasikan 3D dengan waktu singkat dan lebih diandalkan pendeteksian tulangan bertumpuk juga material isolator. Adapun alat untuk mengukur kecepatan rambat dalam beton menggunakan prinsip transmisi ultrasonik yaitu ultrasonic pulse velocity dan prinsip  pulsed echo method (PE) yaitu ultrasonic tomograph portable yang digunakan dalam penelitian ini untuk membandingkan pembacaan pancaran gelombang longitudinal dan transversal pada struktur pelat lantai beton. Tampilan pemrosesan data ultrasonic tomograph portable menggunakan teknologi SAFT (synthetic aperture focusing technique) sehingga selain dapat menghasilkan kecepatan shearwave alat ini dapat menentukan tulangan. Hasil pengujian ultrasonic tomograph portable menunjukkan kecepatan yang lebih konstan dibandingkan ultrasonic pulse velocity dengan konfigurasi indirect pada struktur pelat beton. ......The development of technology for investigating the quality of concrete structures continues to develop and used to evaluate reinforcement and thickness of the concrete cover in reinforced concrete without damaging the structure (Non Destructive Test). Commonly used tools are Profometer and Ultraportable Ground Penetrating Radar. With different working principles, in this research, a study of the thickness evaluation of the concrete cover, identification of reinforcement and insulating material was carried out, by comparing the results of the profometer, GPR to the 2x2 m floor slab structure. The results of the GPR can be visualized in 3D in a short time and more reliable in detecting stacked reinforcement as well as insulating material. The tool to measure the propagation speed in concrete uses the ultrasonic transmission principle, ultrasonic pulse velocity and the pulsed echo method principle, the ultrasonic tomograph portable used in this study to compare the readings of longitudinal and transverse waves on the concrete floor slab structure. Ultrasonic tomograph portable data processing uses SAFT technology, in addition producing shearwave speed, this tool can determine reinforcement. The results of the ultrasonic tomograph portable show more constant speed than the UPV with indirect configuration on the concrete slab structure.

Abstrak :
The increased use of polymer matrix composites in structural applications has led to the growing need for a very high level of quality control and testing of products to ensure and monitor performance over time. Non-destructive evaluation (NDE) of polymer matrix composites explores a range of NDE techniques and the use of these techniques in a variety of application areas. Part one provides an overview of a range of NDE and NDT techniques including eddy current testing, shearography, ultrasonics, acoustic emission, and dielectrics. Part two highlights the use of NDE techniques for adhesively bonded applications. Part three focuses on NDE techniques for aerospace applications including the evaluation of aerospace composites for impact damage and flaw characterisation. Finally, the use of traditional and emerging NDE techniques in civil and marine applications is explored in part four. With its distinguished editor and international team of expert contributors, Non-destructive evaluation (NDE) of polymer matrix composites is a technical resource for researchers and engineers using polymer matrix composites, professionals requiring an understanding of non-destructive evaluation techniques, and academics interested in this field.

Abstrak :
ABSTRAK
Teknik untuk mengetahui RFL remaining fatigue life memiliki beberapa cara antara lain dengan teknik thermography. Dalam studi ini telah dilakukan completely rotating bending fatigue testing sesuai dengan standart JIS Z2274 untuk mengukur nilai Nf Fatigue Life dan untuk mengestimasi nilai RFL dengan teknik thermography. Selama pengujian dengan teknik thermography, perubahan temperature benda uji pada titik kritis diukur dengan menggunkan infrared kamera. Dari hasil pengukuran perubahan temperature tersebut telah dilakukan estimasi nilai RFL. Material yang dipakai adalah S45C. Pengujian dilakukan dalam putaran 1600 rpm dengan kondisi suhu lingkungan 25 C. Akhirnya dapat disimpulkan bahwa nilai RFL hasil estimasi dengan teknik thermograpy sangat mendekati dengan nilai RFL hasil pengujian.

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ABSTRACT
There are several techniques to estimate the RFL remaining fatigue life such as thermography techniques. In this study, rotating bending fatigue testing has been done completely with the standard JIS Z2274 to measure the value of Nf Fatigue Life and to estimate the value of the RFL using thermography techniques. During the testing with the techniques, the positive of temperature gradient of the specimen at the critical point is measured by using the infrared camera. From the result of temperature change, the RFL value can be estimated. The material used is S45C. The test is carried out in 1600 rpm with ambient temperature of 25 C. Finally, it can be concluded that the estimated RFL value with thermograpy technique is very close to the value of RFL test result.

Abstrak :
ABSTRAK
Sistem prediksi kedalaman memar dan distribusi kandungan SSC pada jambu berdasarkan waktu penyimpanan dengan menggunakan sistem citra Vis-NIR pada panjang gelombang 400-1000 nm dapat dikembangkan menjadi sistem non-destruktif. Sehingga informasi tambahan yang di dapat tidak hanya dapat membedakan daerah memar namun juga memberikan informasi kedalaman memar dan kandungan SSC pada daerah memar. Sistem yang diusulkan dievaluasi dengan menggunakan 160 sampel jambu dibagi dalam dua kelompok set data, yaitu set data training n = 140 dan set data testing n = 20 . Proses memar pada jambu dilakukan secara manual dengan dijatuhkan bola besi dari ketinggian 200 dan 500 mm dan kemudian sampel dianalisis dengan rentang waktu 0,3,4,5, dan 6 hari setelah dimemarkan. Sistem citra Vis-NIR yang digunakan terdiri dari satu set perangkat, diantaranya workbench, slider, dua sumber cahaya halogen 150W dan kamera citra Vis-NIR yang terhubung ke PC melalui Camera Link. Perangkat lunak sistem terdiri dari pengukuran profil gambar reflektansi, ekstraksi fitur, pemilihan fitur pada data spektral dan spasial, model prediksi kandungan SSC, dan model prediksi kedalaman memar. Model Partial Least Square Regression PLSR digunakan untuk mengembangkan model prediksi pada data spektral semua panjang gelombang. Model PLSR digunakan untuk mendapatkan prediksi nilai kandungan SSC dan kedalaman memar. Hasil yang diprediksi dibandingkan dengan hasil pengukuran uji lab kandungan SSC yang diperoleh dengan menggunakan refraktometer dan kedalaman memar yang diperoleh dengan menggunakan sifat measurement instrumental. Dari hasil kinerja model prediksi didapatkan nilai RMSE pada data testing 0,06 dan koefisien korelasi dari data testing 0,99.Kata kunci : Memar; PLSR; citra Vis-NIR.

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ABSTRACT
Abstract The prediction system of bruising depth in guava based on storage operation using Visual NIR image in the ranges 400 ndash 1000 nm ranges, which could be developed a nondestructive system to predicted the bruise depth of guava. The additional information gained not only the position of the bruised area but also provides depth bruising information. And then, the objective of the research was to develop a nondestructive method for predicting the profile mapping of soluble solid content on bruises guava. The soluble solids content SSC as the parameter fruits was determined and correlated with the bruises area.The proposed system was evaluated using 160 samples of guava were divided in two groups. All of the samples are prepared for the training n 140 and testing n 20 set data. Bruises were manually induced and samples were analyzed 0, 3rd, 4th, 5th and 6th days after bruising. Individual guavas were then subjected to impact test by a steel ball at one of the levels height of impact test, i.e.,200mm and 500mm. The system used consists of a set such as workbench, controllable slider, two halogen light sources and a Visual NIR imaging camera that is connected to PC via Camera Link. The software of system consists of reflectance image profile measurement, feature extraction, feature selection on spectral and spatial data, soluble solids content prediction model, and bruise depth prediction model. The partial least squares regression PLSR models was used to develop prediction models on full wavelengths spectral data. The prediction model is used to get value prediction of soluble solids content and bruising depth. The predicted results compared with the reference measurement result of soluble solids content which obtained using a refractometer and bruising depth which obtained using an optical properties. The full spectral data and parameter fruits were analyzed using the Partial Least Square PLS to obtained prediction model of bruising depth and SSC of bruises guava. The peformance of prediction model provided value of the root mean square error of testing set of 0.06 and the correlation coefficient of a testing set of 0.99. The results of our work indicate that there is a feasibility of implementing hyperspectral imaging technique on the nondestructive bruise depth prediction of guava and suitable in an industrial sorting system for fruit quality, which would be useful for postharvest handling of fruit. Keywords kelebaman bruising , non destructive, Profitability, hyperspectral image Vis NIR.