Rail Track Maintenance Planning: An Assessment Model

In Australia, railway track maintenance costs comprise between 25-35 percent of total freight train operating costs. Track maintenance planning models have been shown to reduce maintenance costs by 5 to 10 percent though improved planning. This paper describes a model which has been developed to deal with the track maintenance planning function at the medium to long-term levels. This model simulates the impacts of degrading railway track conditions and related maintenance work, in contrast to tradition models that mainly use expert systems. The model simulates the degrading track condition using an existing track degradation model. Track condition data from that model is used to determine if safety related speed restrictions are needed and what immediate maintenance work may be required for safe train operations. The model outputs the net present value of the benefits of undertaking a given maintenance strategy, when compared with a base-case scenario. The model approach has advantages over current models in investigating what if scenarios. The track engineer can assess the possible benefits in reduced operating costs from upgrading track infrastructure or from the use of improved maintenance equipment. After describing the model inputs and the assumptions used, the paper deals with the simulation of track maintenance and of train operating costs over time. The results of applying the model to a test track section using a number of different maintenance strategies are also given

Understanding Database Reconstruction Attacks on Public Data

In 2020 the U.S. Census Bureau will conduct the Constitutionally mandated decennial Census of Population and Housing. Because a census involves collecting large amounts of private data under the promise of confidentiality, traditionally statistics are published only at high levels of aggregation. Published statistical tables are vulnerable to DRAs (database reconstruction attacks), in which the underlying microdata is recovered merely by finding a set of microdata that is consistent with the published statistical tabulations. A DRA can be performed by using the tables to create a set of mathematical constraints and then solving the resulting set of simultaneous equations. This article shows how such an attack can be addressed by adding noise to the published tabulations, so that the reconstruction no longer results in the original data

Providing cryptographic security and evidentiary chain-of-custody with the advanced forensic format, library, and tools

This paper presents improvements in the Advanced Forensics Format Library version 3 that provide for digital signatures and other cryptographic protections for digital evidence, allowing an investigator to establish a reliable chain-of-custody for electronic evidence from the crime scene to the court room. No other system for handling and storing electronic evidence currently provides such capabilities. This paper discusses implementation details, user level commands, and the AFFLIB programmer's API.Approved for public release; distribution is unlimited

Notes on the Codling moth

The Codling Moth (Carpocapsa pomonella) is attracting so much attention at present that I hope I may be excused for making some remarks upon the subject. This insect belongs to that family of the Lepidoptera called Tortricidae (in French, "Tordeuses"), on account of the general habit of their larvae of "twisting" or rolling up the leaves of plants of their abode, usually those leaves enclosing a young shoot or bud. They then devour such leaves, shoots or buds, to the great detriment of the plant attacked. A few take up their abode in the interior or fruits, especially the apple, pear, and plum

Discrepancy between strength and function in adults with obstetric brachial plexus lesions

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108706/1/dmcn12525.pd

PENGEMBANGAN MEDIA PEMBELAJARAN KIMIA DENGAN MATERI POKOK KARBOHIDRAT BERBASIS WEBSITE SEBAGAI SUMBER BELAJAR MANDIRI UNTUK SISWA SMA/MA

Penelitian ini merupakan penelitian pengembangan di bidang pendidikan kimia. Tujuan penelitian ini adalah mengembangkan media pembelajaran kimia dengan materi pokok karbohidrat berbasis website sebagai sumber belajar mandiri untuk siswa SMA/MA dan mengetahui kualitas media pembelajaran kimia tersebut berdasarkan penilaian lima guru kimia SMA di Daerah Istimewa Yogyakarta. Model pengembangan yang digunakan adalah model prosedural, yaitu model yang bersifat deskriptif melalui beberapa langkah yang harus diikuti untuk menghasilkan produk. Produk awal ditinjau dan diberi masukan oleh dosen pembimbing, peer reviewer, ahli media dan ahli materi, dan selanjutnya direvisi. Produk revisi dinilai dan diberi masukan oleh lima guru kimia SMA (reviewer) di Daerah Istimewa Yogyakarta. Instrumen penilaian media pembelajaran ini berisi lima aspek penilaian, yaitu: (1) aspek kebenaran, keluasan, dan kedalaman konsep, (2) aspek kebahasaan yang digunakan, (3) aspek keterlaksanaan, (4) aspek tampilan dan (5) aspek kemudahan penggunaan. Kelima aspek tersebut terdiri atas 19 indikator penilaian. Hasil penilaian yang berupa skor kemudian di gabung dan dianalisis dengan pedoman kriteria penilaian ideal. Hasil penelitian pengembangan ini adalah Compact Disc (CD) media pembelajaran berbasis website, dengan pokok bahasan karbohidrat untuk siswa SMA/MA. Media pembelajaran kimia berbasis website yang dikembangkan memperoleh skor rata-rata 81,6 dari skor maksimal 100, dengan persentase keidealan 81,6 %. Berdasarkan rentang persentase keidealan, media pembelajaran kimia berbasis website dengan materi pokok karbohidrat ini mempunyai kategori kualitas baik dan dapat digunakan sebagai sumber pembelajaran mandiri untuk peserta didik tingkat SMA

Book Review of iPhone and iOS Forensic: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices

Hoog, A., and Strzempka, K. (2011).  iPhone and iOS Forensic: Investigation, Analysis and Mobile Security for Apple iPhone, iPad and iOS Devices. Syngress, Elsevier, xv + 310 pages; ISBN-10: 1597496596; ISBN-13: 978-1597496599, $69.95Reviewed by Simson Garfinkel, Naval Postgraduate SchoolIn April 2011 news outlets around the world revealed shocking news about Apple’s iPhone: for reasons that were not apparently clear, every iPhone contained a small SQLite database that logged where and when the user had been whenever the phone was turned on, and those records went back for pretty much as long as the user had owned their phone. Apple eventually declared that the data cache was the result of a bug and issued a software update to prune the database (it had previously grown without limit). Privacy activists rejoiced that their beloved iPhones were once again trustworthy. But forensics examiners just shook their heads: many had known about the iPhone’s tracking capabilities for more than a year and had kept quiet. They had made good use of that data. Apple’s pro-privacy patch was actually a setback for law enforcement.(see PDF for full review)</p