PENDUGAAN DATA HILANG PADA RANCANGAN ACAK KELOMPOK LENGKAP DENGAN METODE YATES DAN ALGORITMA EXPECTATION MAXIMIZATION

Dalam sebuah percobaan, seringkali percobaan tidak selamanya berjalan sesuai dengan yang diharapkan. Jika data yang diperoleh dari suatu penelitian hanya sebagian teramati, maka masalah umum dalam percobaan telah terjadi yang dikenal sebagai data hilang. Hal tersebut dapat disebabkan oleh berbagai hal, misalnya perlakuan yang tidak tepat, kerusakan pada obyek percobaan dan data yang tidak logis. Nilai-nilai yang hilang tersebut harus diduga dan diganti sebelum melakukan analisis lebih lanjut. Metode pendugaan data hilang dalam penelitian ini adalah metode Yates dan Algoritma EM. Konsep dasar dalam metode Yates adalah meminimumkan jumlah kuadrat galat, sedangkan konsep dasar Algoritma EM adalah memaksimumkan fungsi likelihood. Pengaplikasian penelitian ini pada Rancangan Acak Kelompok Lengkap (RAKL) dengan besaran perlakuan yang berbeda (3 perlakuan sampai dengan 7 perlakuan) pada 3 kelompok. Pendugaan data hilang dengan metode Algoritma EM lebih baik digunakan dari pada metode Yates jika posisi data hilang secara acak dan dalam satu perlakuan, berbeda halnya jika data hilang dalam satu kelompok lebih baik menggunakan metode Yates dibandingkan metode Algoritma EM. Pendugaan data hilang dengan metode Yates dan algoritma EM menghasilkan nilai dugaan yang sama jika ada 1 data hilang, sehingga sama-sama baik digunakan. Kata Kunci : Rancangan acak kelompok lengkap, data hilang, metode Yates, metode Algoritma E

Development of Guidelines for Inspection, Repair, and Use of Portable Concrete Barriers\u2014Volume 1: Technical Report

Project 0-7059Defining the service life of portable concrete barriers (PCBs) is important to reduce the risk of inferior, unsafe barriers being used on Texas roadways. The Manual for Assessing Safety Hardware (MASH) implementation agreement allows state transportation agencies to continue the use of PCBs manufactured on or before December 31, 2019, and successfully tested to standards in National Cooperative Highway Research Program Report 350 or the 2009 edition of MASH throughout their normal service life. Damage to the precast barriers can occur in transit, in storage, or due to vehicular impact. When damage to the connections occurs, cracks, broken corners, and many other forms of damage can be sustained by the barrier. No federal guidance, however, has been developed to determine life expectancy for PCBs. There is a need to develop guidelines addressing the type and extent of barrier damage that constitute replacement of the segment

Laser generation and detection techniques for developing transfer functions to characterize the effect of geometry on elastic wave propagation

Ph.D.Laurence J. Jacob

Traffic signal supporting structures and methods

The embodiments presented herein include systems and methods for mitigating fatigue and fracture in mast-and-arm supporting structures caused by wind and other excitation forces. In particular, the embodiments presented herein utilize pre-stressed devices to reduce tensile stresses in arm-to-mast connections and/or mast-to-foundation connections of the traffic signal supporting structures. Present embodiments may employ stressed cables, post-tensioned bars (e.g., DYWIDAG bars), threaded rods, and so forth, to mitigate fatigue and fracture in the traffic signal supporting structures.U

Optical Techniques to Develop Transfer Functions to Remove Geometric Features in Acoustic Emission Signals

A measured acoustic emission signal depends upon three distinct factors: its source; component geometry and material properties; and receiving sensor and instrumentation. Each of these three elements must be understood in order to effectively identify and characterize measured acoustic emission waveforms.</p

Non-Destructive Evaluation Method Based On Dynamic Invariant Stress Resultants

Most of the vibration based damage detection methods are based on changes in frequencies, mode shapes, mode shape curvature, and flexibilities. These methods are limited and typically can only detect the presence and location of damage. Current methods seldom can identify the exact severity of damage to structures. This paper will present research in the development of a new non-destructive evaluation method to identify the existence, location, and severity of damage for structural systems. The method utilizes the concept of invariant stress resultants (ISR). The basic concept of ISR is that at any given cross section the resultant internal force distribution in a structural member is not affected by the inflicted damage. The method utilizes dynamic analysis of the structure to simulate direct measurements of acceleration, velocity and displacement simultaneously. The proposed dynamic ISR method is developed and utilized to detect the damage of corresponding changes in mass, damping and stiffness. The objectives of this research are to develop the basic theory of the dynamic ISR method, apply it to the specific types of structures, and verify the accuracy of the developed theory. Numerical results that demonstrate the application of the method will reflect the advanced sensitivity and accuracy in characterizing multiple damage locations

Non-Destructive Evaluation Method Based On Dynamic Invariant Stress Resultants

Most of the vibration based damage detection methods are based on changes in frequencies, mode shapes, mode shape curvature, and flexibilities. These methods are limited and typically can only detect the presence and location of damage. Current methods seldom can identify the exact severity of damage to structures. This paper will present research in the development of a new non-destructive evaluation method to identify the existence, location, and severity of damage for structural systems. The method utilizes the concept of invariant stress resultants (ISR). The basic concept of ISR is that at any given cross section the resultant internal force distribution in a structural member is not affected by the inflicted damage. The method utilizes dynamic analysis of the structure to simulate direct measurements of acceleration, velocity and displacement simultaneously. The proposed dynamic ISR method is developed and utilized to detect the damage of corresponding changes in mass, damping and stiffness. The objectives of this research are to develop the basic theory of the dynamic ISR method, apply it to the specific types of structures, and verify the accuracy of the developed theory. Numerical results that demonstrate the application of the method will reflect the advanced sensitivity and accuracy in characterizing multiple damage locations