Analysis of Tizen Security Model and Ways of Bypassing It on Smart TV Platform

The smart TV market is growing at an ever faster pace every year. Smart TVs are equipped with many advanced functions, allow users to search, chat, browse, share, update, and download different content. That is one of the reason why smart TVs became a target for the hacker community. In this article, we decided to test security of Tizen operating system, which is one of the most popular smart TV operating systems. Tizen is used on many different devices including smartphones, notebooks, wearables, infotainment systems, and smart TVs. By now, there are articles which present security mechanisms of Tizen OS, and sometimes with a way to bypass them; however, none of them are applicable to the smart TVs. In the article, we focused on developing an algorithm that will allow us to gain root access to the smart TV. The proposed attack scenario uses CVE-2014-1303 and CVE-2015-1805 bugs to bypass or disable security mechanisms in Tizen OS and finally gain root access.

Simulated Computer Adaptive Testing Administration with Remote Proctoring for Offsite Assessment in Mathematics

<div><p>This study examines remote proctoring as emerging practice for ascertaining the validity of offsite test administration regarding test security. While Computer Adaptive Testing (CAT) has the potentials for greater precision in determining examinees ability level, its gains can be jeopardized with off-site testing if the test is not ensured. This study simulated CAT assessment while focusing on item administration, varying the option of using pre-test items and how it impacts students' ability estimation and item exposure. Monte-Carlo simulation was employed to generate data for answering the research questions raised for the study. The study's findings revealed that CAT administration was more consistent with no pre-test items once tightly controlled at ±2theta level, upon which recommendations were made. This finding is particularly germane, with more institutions moving their assessments online and rapidly becoming a new normal as an aftermath of the Covid-19 pandemic.</p></div><div><br></div>The data for this study were generated from computer simulations using SimulCAT, a free software package designed by Dr. K. C. T. Han of Graduate Management Admission Council.<p></p>

Simulated Computer Adaptive Testing Administration with Remote Proctoring for Offsite Assessment in Mathematics

<div><p>This study examines remote proctoring as emerging practice for ascertaining the validity of offsite test administration regarding test security. While Computer Adaptive Testing (CAT) has the potentials for greater precision in determining examinees ability level, its gains can be jeopardized with off-site testing if the test is not ensured. This study simulated CAT assessment while focusing on item administration, varying the option of using pre-test items and how it impacts students' ability estimation and item exposure. Monte-Carlo simulation was employed to generate data for answering the research questions raised for the study. The study's findings revealed that CAT administration was more consistent with no pre-test items once tightly controlled at ±2theta level, upon which recommendations were made. This finding is particularly germane, with more institutions moving their assessments online and rapidly becoming a new normal as an aftermath of the Covid-19 pandemic.</p></div><div><br></div>The data for this study were generated from computer simulations using SimulCAT, a free software package designed by Dr. K. C. T. Han of Graduate Management Admission Council.<p></p>

Tensions will undermine US-Mexico cooperation

Significance The meetings follow a period of increased strain in the bilateral relationship, over the US arrest, and subsequent release, of former Mexican Defence Minister General Salvador Cienfuegos. They also come amid a surge in undocumented migration, one of several long-standing issues that will increase tensions. Impacts The more affable tone of US-Mexican relations under Biden will not alter long-standing US drug and migration control priorities. US engagement with, and funding for, Mexican human rights and anti-corruption NGOs could foster tensions with the AMLO administration. AMLO’s poor record of containing criminal violence and his enduring aversion to coercive law enforcement will test security cooperation. Poor security cooperation will damage both parties, making the rescue and redefinition of bilateral security cooperation crucial.

Alternative item selection strategies for improving test security in computerized adaptive testing of the algorithm

Salah satu metode estimasi kemampuan yang banyak diaplikasikan pada algoritma Computerized Adaptive Testing (CAT) adalah Maximum Likeli-hood Estimation (MLE). Metode MLE mempunyai kekurangan yaitu ketidakmampuan menemukan solusi estimasi kemampuan peserta tes ketika skor peserta masih belum berpola. Bila ada peserta tes yang memperoleh skor 0 atau skor sempurna, maka untuk menentukan estimasi kemampuan peserta tes umumnya menggunakan model step size. Namun, model step-size tersebut mengakibatkan item exposure. Item exposure merupakan fenomena dimana butir-butir soal tertentu akan lebih sering muncul dibandingkan dengan butir-butir soal yang lain. Hal tersebut membuat tes menjadi tidak aman karena butir-butir soal yang sering muncul akan lebih mudah pula untuk dikenali. Kajian ini mencoba memberikan alternatif strategi dengan cara memodifikasi model step-size dan dilanjutkan dengan merandom hasil perhitungan fungsi informasi yang diperoleh. Berdasarkan hasil kajian didapatkan bahwa alternatif strategi pemilihan butir soal ini mampu menghasilkan kemunculan butir soal yang lebih bervariasi sehingga dapat meningkatkan keamanan tes pada CAT.Kata kunci: item exposure, step-size, adaptive testing AbstractOne method of capability estimation that is widely applied to the Computerized Adaptive Testing (CAT) algorithm is Maximum Likeli-hood Estimation (MLE). The MLE method has the disadvantage of being unable to find a solution to the test taker's ability when the participant's score is not patterned. If there are test takers who get a score of 0 or perfect score, then to determine the ability of the test takers to generally use the step size model. However, the step-size model results in exposure items. The exposure item is a phenomenon where certain items will appear more often than other items. This makes the test insecure because items that often appear will be easier to recognize. This study tries to provide an alternative strategy by modifying the step-size model and proceed by randomizing the results of the calculation of the information function obtained. Based on the results of the study, it was found that alternative item selection strategies were able to produce the appearance of more varied items so as to improve the safety of tests on the CAT.

Mexico political dynamics test security strategies

Subject Insecurity in Mexico. Significance Mexico saw its highest murder rate on record in 2019, according to figures released by the Executive Secretariat of the National System of Public Security (SESNSP) on January 20. The news follows President Andres Manuel Lopez Obrador (AMLO)’s announcement last month of a new ten-point security plan. While AMLO recognises the gravity of the situation, however, his plans remain vague and lack a coherent strategy. Impacts AMLO’s poor record on curbing violence does not inspire optimism about his most recent security template. Arbitrary and poorly explained security decisions will pose security threats for governors. AMLO’s constraints on the use of offensive force will break down in local contexts.