Security and usability in password authentication

This thesis investigates the human-factor problems in password authentication and proposes some usable solutions to these problems by focusing on both forms of knowledge based authentication: textual passwords and graphical passwords. It includes a range of empirical studies to examine users' password-related behaviour and practices in authentication, and helps users to adopt secure password behaviour. This thesis consists of two parts. The first part focuses on traditional text-based passwords. Design flaws and usability issues of existing text-password mechanisms used by many organisations cause employees to adopt insecure password practices. The first work in this thesis investigates the reasons for employees' lack of motivation regarding password protection against security failures. An empirical study is conducted to identify the factors causing employees’ insecure behaviours in organisations, and several persuasion strategies are tested to persuade employees to use passwords more safely. The results of the study revealed that some persuasion strategies are effective in motivating users to adopt good password practices. The study also found that the failure of password policies and authentication schemes deployed by organisations is a common problem among the organisations. Considering the results of the first study, in the second work of this thesis, a password guideline/advice study is conducted to help users to create stronger and more memorable passwords. A password guideline including a number of password creation methods and a persuasive message is proposed, and its effectiveness in improving the strength of user-chosen passwords is evaluated. The results show that the users who received the proposed guideline produced stronger and more memorable passwords than the users followed the usual password restrictions while creating their passwords. The results also demonstrate that the given password creation methods can be helpful and inspirational for users to create their own encryption formula. All these works reveal the weaknesses of user-chosen textual passwords and inefficacy of existing text-based password mechanisms. Although these studies show that text-based password mechanisms can be strengthened, they are still problematic where usability is concerned. Thus, the second part of this thesis focuses on another form of knowledge-based authentication: graphical passwords. A novel hybrid authentication scheme integrating text and images is introduced to minimise the brute force and shoulder surfing attacks which text and graphical passwords suffer. In the last work of this thesis, the proposed hybrid scheme is implemented and evaluated. The evaluation shows that the proposed scheme provides security and usability at the same time, and it also makes the password creation process enjoyable for users. In summary, the thesis contributes to the analysis of some key security and usability problems which arise in knowledge-based authentication. A series of empirical studies has been conducted. Based on their results, usable solutions to the human-factor problems in password-based authentication are proposed and evaluated

Un análisis de Cuentos dramáticos y Cuentos trágicos de Emilia Pardo Bazán

La exquisita producción cuentística de doña Emilia Pardo Bazán (1851-1921) destaca particularmente en el conjunto de su obra narrativa por varias razones entre las cuales llama la atención su elevada cantidad —en torno a seiscientos cuentos, si bien no es una cifra definitiva— y su cuidada calidad literaria. Otro aspecto importante lo constituye la forma estructural y la variedad temática distinguida de los cuentos pardobazanianos. A partir de 1892 la autora empieza a recoger sus cuentos en varias colecciones, que posteriormente se incluirán en sus Obras completas. La presente investigación nace con el propósito de hacer un análisis crítico sobre dos colecciones, Cuentos dramáticos (1901) y Cuentos trágicos (1912), recogidas y publicadas por la propia Emilia Pardo Bazán. Nos planteamos descubrir de qué manera aborda la autora la temática dramática y trágica en sus narraciones, tal y como indican sus títulos. El corpus entero que examinamos está conformado por sesenta y cuatro cuentos en total (treinta y siete títulos para Cuentos dramáticos y veintisiete para Cuentos trágicos). Las dos recopilaciones escogidas han sido estudiadas desde temáticas diferentes, todas ellas comprendidas en el trasfondo del dramatismo y tragedia de la época. Ambos conjuntos de textos ofrecen un amplio abanico temático, desde las cuestiones más sociales como la familia, la mujer, los hijos y la pareja contemporánea, hasta los asuntos psicológicos, históricos, policiacos y fantásticos, entre otros. Se han concretado los temas que descuellan en cada cuento, tras una lectura minuciosa, y de esta forma se han clasificado todos los cuentos del corpus, uno por uno, bajo dos bloques..

Administrator’s Views On The Studies Carried Out On The Equipment Of Schools To Increase Internal Efficiency In Education And The Effect Of These Studies On The Academic Success Of Students

Bu araştırmanın amacı, eğitimde iç verimliliği artırmak amacıyla okulların donanımlarında yapılan çalışmaların amaca hizmet edip etmediğini okul yöneticilerinin görüşlerine göre belirlemek ve bu çalışmaların akademik başarıya etkisini bulmaktır. öğrencilerin başarılarının arttırılması ve eğitimde iç verimliliğin artırılmasına yönelik çözüm önerilerinin belirlenmesidir. Araştırmada nitel araştırma yöntemlerinden durum çalışması deseni kullanılmıştır. Araştırmanın çalışma grubunu 2022-2023 eğitim-öğretim yılında Tokat Artova ilçesinde ilkokul memuru olarak görev yapan 10 okul yöneticisi oluşturmuştur. Veriler yarı yapılandırılmış görüşme tekniğiyle toplanmış ve betimsel analiz yöntemiyle analiz edilmiştir. Araştırma sonuçlarına göre okulların donanım eksikliklerinin eğitimde iç verimliliği olumsuz etkilediği, bunun da öğrencilerin devam oranlarını düşürdüğü ve akademik başarıyı olumsuz etkilediği sonucuna varılmıştır. Katılımcıların çoğu okullarında eksiklikler olduğunu ve bu eksikliklerin öğrencilere olumsuz yansıdığını ifade etmiştir. Okullarda deneyimli personel eksikliği ve okulların fiziki ve teknolojik imkanlarının yetersizliği eğitim sürecini olumsuz etkilemektedir. Eğitimde verimlilik ve öğrencilerin ilköğretim hedeflerine ulaşmasında okul öncesi eğitimin büyük önem taşıdığı sonucuna varılmıştır. Eğitim kurumlarında hijyen ve ısınma sorunlarının olması ve bu durumların öğrencilerin hastalanmasına neden olması ve bu durumun devam oranlarının düşmesine neden olması eğitimde hedeflere ulaşmada sorunlara yol açmıştır.Çocukların yeteneklerine yönelik fiziki olanakların olmayışı okula olan ilgiyi azaltmakta ve eğitimin kalitesini düşürmektedir. Teknolojik, sosyal ve fiziksel olanakların yetersiz olması öğrencilerde aidiyet duygusunu olumsuz etkileyerek okulun akademik başarısını düşürmektedir. Fen ve laboratuvar fiziki olanaklarının ve teknolojik materyallerin yetersizliğinin öğrencilerin yaparak öğrenme ve yaratıcı düşünme becerilerini körelttiği sonucuna varılmıştır. Ulaşımlı okullarda ulaşımda yaşanan aksaklıklar öğrencilerin okula devam oranlarını düşürmekte, bu da eğitimdeki verimliliği olumsuz etkilemektedir. Kırsal okullardaki donanım eksikliği öğrencilerin akademik başarısını düşürmektedir. İlçedeki ilköğretim okullarının tamamında donanım açısından eksiklikler bulunmaktadır. Katılımcılar okul ve dersliklerin donanım, eğitim materyali, resim, müzik ve fen laboratuvarlarının eksik olduğunu, bu sorunların çözümünde yetersiz kaldıklarını belirtmişlerdir. Görüşülen katılımcılar, okul öncesi eğitim derslerinin tüm okullarda ve binada zorunlu olması, fiziki ortamların iyileştirilmesi, okulların donanım eksikliklerinin giderilmesi gerektiğini belirtmişlerdir. Okul bazlı bir bütçe olmasına rağmen okula gönderilen para yetersiz, yeterli miktarda gönderilmeli, teknolojik donanım eksiklikleri giderilmeli, her okula alanında uzman öğretmenler görevlendirilmeli, okulların personel ve donanım eksiklikleri giderilmeli. Eğitimde verimliliğin artırılması için gerekli materyaller okullara gönderilmeden önce ihtiyaçların önceden belirlenmesi ve donanım eksikliklerinin tamamen tamamlanması gerekmektedir. Bulundular

How Image Degradations Affect Deep CNN-based Face Recognition?

Face recognition approaches that are based on deep convolutional neural networks (CNN) have been dominating the field. The performance improvements they have provided in the so called in-the-wild datasets are significant, however, their performance under image quality degradations have not been assessed, yet. This is particularly important, since in real-world face recognition applications, images may contain various kinds of degradations due to motion blur, noise, compression artifacts, color distortions, and occlusion. In this work, we have addressed this problem and analyzed the influence of these image degradations on the performance of deep CNN-based face recognition approaches using the standard LFW closed-set identification protocol. We have evaluated three popular deep CNN models, namely, the AlexNet, VGG-Face, and GoogLeNet. Results have indicated that blur, noise, and occlusion cause a significant decrease in performance, while deep CNN models are found to be robust to distortions, such as color distortions and change in color balance.Comment: 8 pages, 3 figure

Validity and Reliability Evidence of Professional Obsolescence Scale According to Different Test Theories

This study aims to develop a scale that will determine the factors causing professional obsolescence in the field of education. In this context, the Professional Obsolescence Scale (POS) has been developed to determine the professional and organizational obsolescence of primary, secondary and high school administrators. In this scale development process, steps were followed in line with the suggestions of Crocker and Algina (2006) and Cronbach (1984). Firstly, 63 items were prepared and 991 school principals participated the study. R (version 4.0.1) software was used to analyze the data. Item and test parameters and information functions have been estimated using Samejima's Graded Response Model based on Item Response Theory. Principal Axis Analysis was performed for the construct validity of the scale, and four-dimensions structure with 47 items has been obtained. These dimensions are named as "Being Open to Professional Development", "Job-Ability Harmony in Profession", "Organizational Support in Professional Development", "Professional Burnout". The scores obtained from each dimension are evaluated within themselves. It has been observed that each dimension fulfills the conditions of unidimensionality, local independence, model-data fit and parameter invariance. According to the Classical Test Theory, Cronbach Alpha coefficients are between 0.807 and 0.945. The Stratified Alpha coefficient calculated for the whole scale is 0.94. According to the Item Response Theory, the marginal reliability coefficients were between 0.857 and 0.936 and the empirical reliability coefficients were found between 0.854 and 0.938

A study on the Chinese learning situation and motivation of the students from Turkey

随着中国经济的快速发展，国际影响力不断提高，汉语的作用也必然会越来越大，如今越来越多的土耳其人来到中国学习汉语。第二语言的学习和母语学习不同，在第二语言学习的研究中，动机属于学习者个体差异因素，它是影响第二语言学习的重要因素之一。根据目前学术界的动机研究来看，影响学习的动机有多种，如马斯洛的内在动机与外在动机；Trambley和Gardner的工具型动机和融合型动机，以及他们后来在此基础上发展出来的扩展动机理论等等。不同的动机发挥不同的动力作用，单纯动机支配下的学习难以延续，存在着巨大的学习障碍。结合多种动机能获得比单一动机更为理想的效果。 本文通过问卷调查的数据探讨来到中国学习汉语的土...With the rapid economic development in China, the international influence has improved a lot. Nowadays more and more Turkish people choose to settle down in China and to learn Chinese. However, it is quite different to learn a second language comparing to learning the tongue language. According to the most popular theory in the world, a large number of factors could affect the study motive when it...学位：教育硕士院系专业：海外教育学院_汉语国际教育硕士学号：2652014115453

Correlation between the serum and tissue levels of oxidative stress markers and the extent of inflammation in acute appendicitis

OBJECTIVES: To determine the serum and tissue levels of markers of impaired oxidative metabolism and correlate these levels with the histopathology and Alvarado score of acute appendicitis patients. METHOD: Sixty-five acute appendicitis patients (mean age, 31.4±12.06 years; male/female, 30/35) and 30 healthy control subjects were studied. The Alvarado score was recorded. Serum samples were obtained before surgery and 12 hours postoperatively to examine the total antioxidant status, total oxidant status, paraoxonase, stimulated paraoxonase, arylesterase, catalase, myeloperoxidase, ceruloplasmin, oxidative stress markers (advanced oxidized protein products and total thiol level) and ischemia-modified albumin. Surgical specimens were also evaluated. RESULTS: The diagnoses were acute appendicitis (n = 37), perforated appendicitis (n = 8), phlegmonous appendicitis (n = 12), perforated+phlegmonous appendicitis (n = 4), or no appendicitis (n = 4). The Alvarado score of the acute appendicitis group was significantly lower than that of the perforated+phlegmonous appendicitis group (p = 0.004). The serum total antioxidant status, total thiol level, advanced oxidized protein products, total oxidant status, catalase, arylesterase, and ischemia-modified albumin levels were significantly different between the acute appendicitis and control groups. There was no correlation between the pathological extent of acute appendicitis and the tissue levels of the markers; additionally, there was no correlation between the tissue and serum levels of any of the parameters. CONCLUSIONS: The imbalance of oxidant/antioxidant systems plays a role in the pathogenesis acute appendicitis. The Alvarado score can successfully predict the presence and extent of acute appendicitis

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely