17 research outputs found

    Privacy of User Identities in Cellular Networks

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    This thesis looks into two privacy threats of cellular networks. For their operations, these networks have to deal with unique permanent user identities called International Mobile Subscriber Identity (IMSI). One of the privacy threats is posed by a device called IMSI catcher. An IMSI catcher can exploit various vulnerabilities. Some of these vulnerabilities are easier to exploit than others. This thesis looks into fixing the most easily exploitable vulnerability, which is in the procedure of identifying the subscriber. This vulnerability exists in all generations of cellular networks prior to 5G. The thesis discusses solutions to fix the vulnerability in several different contexts. One of the solutions proposes a generic approach, which can be applied to any generation of cellular networks, to fix the vulnerability. The generic approach uses temporary user identities, which are called pseudonyms, instead of using the permanent identity IMSI. The thesis also discusses another solution to fix the vulnerability, specifically in the identification procedure of 5G. The solution uses Identity-Based Encryption (IBE), and it is different from the one that has been standardised in 5G. Our IBE-based solution has some additional advantages that can be useful in future works. The thesis also includes a solution to fix the vulnerability in the identification procedure in earlier generations of cellular networks. The solution fixes the vulnerability when a user of a 5G network connects to those earlier generation networks. The solution is a hybridisation of the pseudonym-based generic solution and the standardised solution in 5G. The second of the two threats that this thesis deals with is related to the standards of a delegated authentication system, known as Authentication and Key Management for Applications (AKMA), which has been released in July 2020. The system enables application providers to authenticate their users by leveraging the authentication mechanism between the user and the user's cellular network. This thesis investigates what requirements AKMA should fulfil. The investigation puts a special focus on identifying privacy requirements. It finds two new privacy requirements, which are not yet considered in the standardisation process. The thesis also presents a privacy-preserving AKMA that can co-exist with a normal-mode AKMA.Väitöskirjassa tutkitaan kahta yksityisyyteen kohdistuvaa uhkaa mobiiliverkoissa. Näissä verkoissa käyttäjät tunnistetaan yksikäsitteisen pysyvän identiteetin perusteella. Hyökkääjä voi uhata käyttäjän yksityisyyttä sellaisen radiolähettimen avulla, joka naamioituu mobiiliverkon tukiasemaksi. Tällainen väärä tukiasema voi pyytää lähellä olevia mobiililaitteita kertomaan pysyvän identiteettinsä, jolloin hyökkääjä voi esimerkiksi selvittää, onko tietyn henkilön puhelin lähistöllä vai ei. Väitöskirjassa selvitetään, millaisilla ratkaisuilla tämän tyyppisiltä haavoittuvuuksilta voidaan välttyä. Viidennen sukupolven mobiiliteknologian standardiin on sisällytetty julkisen avaimen salaukseen perustuva suojaus käyttäjän pysyvälle identiteetille. Tällä ratkaisulla voidaan suojautua väärän tukiaseman uhkaa vastaan, mutta se toimii vain 5G-verkoissa. Yksi väitöskirjassa esitetyistä vaihtoehtoisista ratkaisuista soveltuu käytettäväksi myös vanhempien mobiiliteknologian sukupolvien yhteydessä. Ratkaisu perustuu pysyvän identiteetin korvaamiseen pseudonyymillä. Toinen esitetty ratkaisu käyttää identiteettiin pohjautuvaa salausta, ja sillä olisi tiettyjä etuja 5G-standardiin valittuun, julkisen avaimen salaukseen perustuvaan menetelmään verrattuna. Lisäksi väitöskirjassa esitetään 5G-standardiin valitun menetelmän ja pseudonyymeihin perustuvan menetelmän hybridi, joka mahdollistaisi suojauksen laajentamisen myös aiempiin mobiiliteknologian sukupolviin. Toinen väitöskirjassa tutkittu yksityisyyteen kohdistuva uhka liittyy 5G-standardin mukaiseen delegoidun tunnistautumisen järjestelmään. Tämä järjestelmä mahdollistaa käyttäjän vahvan tunnistautumisen automaattisesti mobiiliverkon avulla. Väitöskirjassa tutkitaan järjestelmälle asetettuja tietoturvavaatimuksia erityisesti yksityisyyden suojan näkökulmasta. Työssä on löydetty kaksi vaatimusta, joita ei ole toistaiseksi otettu huomioon standardeja kehitettäessä. Lisäksi työssä esitetään ratkaisu, jolla delegoidun tunnistautumisen järjestelmää voidaan laajentaa paremmin yksityisyyttä suojaavaksi

    Computer Vision-Based Gender Detection from Facial Image

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    face detection, object detection, image processing Abstract � Computer vision-based gender detection from facial images is a challenging and important task for computer vision-based researchers. The automatic gender detection from face images has potential applications in visual surveillance and human-computer interaction systems (HCI). Human faces provide important visual information for gender perception. This research presents a novel approach for gender detection from facial images. The system can automatically detect face from input images and the detected facial area is taken as region of interest (ROI). Discrete Cosine Transformation (DCT) of that ROI plays an important role in gender detection. A gender knowledgebase of the processed DCT is created utilizing supervised learning. To detect gender, input image is passed through a classifier which is based on that knowledgebase. To improve the matching accuracy Local Binary Pattern (LBP) of the ROI is done before converting it into DCT. This research has experimented on a database of more than 4000 facial images which are mainly of this subcontinent in order to evaluate the performance of the proposed system. The average accuracy rate achieved by the system is more than 78%. 1

    Traditional Islamic Herbal Medicine and Complementary Therapies

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    Herbal products found abundantly in several plants are the rich source of phytochemicals with a wide range of pharmacological activities and few adverse effects. Medicinal plants contain active ingredients that assist the body in reestablishing its natural balance and healing itself. Various herbs, which are commonly used in traditional Islamic medicine, can have an impact on human body systems. Natural products are primary sources of effective drugs with novel structures and distinct mechanisms of action for the treatment of various types of complications as well as the drug discovery process. The various pharmacological properties such as antimicrobial, anticancer, antioxidant, antihypertensive, immunomodulatory, anti-inflammatory and anti-diabetic properties of several natural products are well documented in the Ayurveda and Unani system of medicine. Some of the natural products’ active ingredients have been documented, but the majority are still being researched as complementary medicine. As a result, more research is required to investigate their complementary medicine system. The present chapter provides a comprehensive update on selected traditional Islamic medicinal plants and their bioactive products mentioned in Islamic scriptures as complementary therapies to various diseases. The chapter also provides an in-depth update of pharmacological and clinical studies of natural products with special emphasis on cancer and diabetes

    Quality Control of Mass-Produced GEM Detectors for the CMS GE1/1 Muon Upgrade

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    The series of upgrades to the Large Hadron Collider, culminating in the High Luminosity Large Hadron Collider, will enable a significant expansion of the physics program of the CMS experiment. However, the accelerator upgrades will also make the experimental conditions more challenging, with implications for detector operations, triggering, and data analysis. The luminosity of the proton-proton collisions is expected to exceed 23×10342-3\times10^{34}~cm2^{-2}s1^{-1} for Run 3 (starting in 2022), and it will be at least 5×10345\times10^{34}~cm2^{-2}s1^{-1} when the High Luminosity Large Hadron Collider is completed for Run 4. These conditions will affect muon triggering, identification, and measurement, which are critical capabilities of the experiment. To address these challenges, additional muon detectors are being installed in the CMS endcaps, based on Gas Electron Multiplier technology. For this purpose, 161 large triple-Gas Electron Multiplier detectors have been constructed and tested. Installation of these devices began in 2019 with the GE1/1 station and will be followed by two additional stations, GE2/1 and ME0, to be installed in 2023 and 2026, respectively. The assembly and quality control of the GE1/1 detectors were distributed across several production sites around the world. We motivate and discuss the quality control procedures that were developed to standardize the performance of the detectors, and we present the final results of the production. Out of 161 detectors produced, 156 detectors passed all tests, and 144 detectors are now installed in the CMS experiment. The various visual inspections, gas tightness tests, intrinsic noise rate characterizations, and effective gas gain and response uniformity tests allowed the project to achieve this high success rate

    Production and validation of industrially produced large-sized GEM foils for the Phase-2 upgrade of the CMS muon spectrometer

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    The upgrade of the CMS detector for the high luminosity LHC (HL-LHC) will include gas electron multiplier (GEM) detectors in the end-cap muon spectrometer. Due to the limited supply of large area GEM detectors, the Korean CMS (KCMS) collaboration had formed a consortium with Mecaro Co., Ltd. to serve as a supplier of GEM foils with area of approximately 0.6 m2^{2}. The consortium has developed a double-mask etching technique for production of these large-sized GEM foils. This article describes the production, quality control, and quality assessment (QA/QC) procedures and the mass production status for the GEM foils. Validation procedures indicate that the structure of the Korean foils are in the designed range. Detectors employing the Korean foils satisfy the requirements of the HL-LHC in terms of the effective gain, response uniformity, rate capability, discharge probability, and hardness against discharges. No aging phenomena were observed with a charge collection of 82 mC/cm2^{2}. Mass production of KCMS GEM foils is currently in progress
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