المؤلفون: Lee, Seoksu, Jeon, Hyeongchang, Cho, Eun-Sun

مصطلحات موضوعية: Computer Science - Cryptography and Security

الوصف: Code obfuscation involves the addition of meaningless code or the complication of existing code in order to make a program difficult to reverse engineer. In recent years, MBA (Mixed Boolean Arithmetic) obfuscation has been applied to virus and malware code to impede expert analysis. Among the various obfuscation techniques, Mixed Boolean Arithmetic (MBA) obfuscation is considered the most challenging to decipher using existing code deobfuscation techniques. In this paper, we have attempted to simplify the MBA expression. We use an e-graph data structure to efficiently hold multiple expressions of the same semantics to systematically rewrite terms and find simpler expressions. The preliminary experimental result shows that our e-graph based MBA deobfuscation approach works faster with reasonable performance than other approaches do.

الوصول الحر: http://arxiv.org/abs/2404.05431Test

المؤلفون: Anderson, James, Chau, Herman, Cho, Eun-Kyung, Crawford, Nicholas, Hartke, Stephen G., Heath, Emily, Henderschedt, Owen, Kwon, Hyemin, Zhang, Zhiyuan

مصطلحات موضوعية: Mathematics - Combinatorics

الوصف: We introduce a new tool useful for greedy coloring, which we call the forb-flex method, and apply it to odd coloring and proper conflict-free coloring of planar graphs. The odd chromatic number, denoted $\chi_{\mathsf{o}}(G)$, is the smallest number of colors needed to properly color $G$ such that every non-isolated vertex of $G$ has a color appearing an odd number of times in its neighborhood. The proper conflict-free chromatic number, denoted $\chi_{\mathsf{PCF}}(G)$, is the smallest number of colors needed to properly color $G$ such that every non-isolated vertex of $G$ has a color appearing uniquely in its neighborhood. Our new tool works by carefully counting the structures in the neighborhood of a vertex and determining if a neighbor of a vertex can be recolored at the end of a greedy coloring process to avoid conflicts. Combining this with the discharging method allows us to prove $\chi_{\mathsf{PCF}}(G) \leq 4$ for planar graphs of girth at least 11, and $\chi_{\mathsf{o}}(G) \leq 4$ for planar graphs of girth at least 10. These results improve upon the recent works of Cho, Choi, Kwon, and Park.
Comment: 32 pages, 11 figures

الوصول الحر: http://arxiv.org/abs/2401.14590Test

المؤلفون: Carr, MacKenzie, Cho, Eun-Kyung, Crawford, Nicholas, Iršič, Vesna, Pai, Leilani, Robinson, Rebecca

مصطلحات موضوعية: Mathematics - Combinatorics, 05C15

الوصف: An improper interval (edge) coloring of a graph $G$ is an assignment of colors to the edges of $G$ satisfying the condition that, for every vertex $v \in V(G)$, the set of colors assigned to the edges incident with $v$ forms an integral interval. An interval coloring is $k$-improper if at most $k$ edges with the same color all share a common endpoint. The minimum integer $k$ such that there exists a $k$-improper interval coloring of the graph $G$ is the interval coloring impropriety of $G$, denoted by $\mu_{int}(G)$. In this paper, we provide a construction of an interval coloring of a subclass of complete multipartite graphs. This provides additional evidence to the conjecture by Casselgren and Petrosyan that $\mu_{int}(G)\leq 2$ for all complete multipartite graphs $G$. Additionally, we determine improved upper bounds on the interval coloring impropriety of several classes of graphs, namely 2-trees, iterated triangulations, and outerplanar graphs. Finally, we investigate the interval coloring impropriety of the corona product of two graphs, $G\odot H$.
Comment: 17 pages, 8 figures, 7 tables

الوصول الحر: http://arxiv.org/abs/2312.14881Test

المؤلفون: Cho, Eun-Kyung, Culver, Eric, Hartke, Stephen G., Iršič, Vesna

مصطلحات موضوعية: Mathematics - Combinatorics

الوصف: Since Reed conjectured in 1996 that the domination number of a connected cubic graph of order $n$ is at most $\lceil \frac13 n \rceil$, the domination number of cubic graphs has been extensively studied. It is now known that the conjecture is false in general, but Henning and Dorbec showed that it holds for graphs with girth at least $9$. Zhu and Wu stated an analogous conjecture for 2-connected cubic planar graphs. In this paper, we present a new upper bound for the domination number of subcubic planar graphs: if $G$ is a subcubic planar graph with girth at least 8, then $\gamma(G) < n_0 + \frac{3}{4} n_1 + \frac{11}{20} n_2 + \frac{7}{20} n_3$, where $n_i$ denotes the number of vertices in $G$ of degree $i$, for $i \in \{0,1,2,3\}$. We also prove that if $G$ is a subcubic planar graph with girth at least 9, then $\gamma(G) < n_0 + \frac{13}{17} n_1 + \frac{9}{17} n_2 + \frac{6}{17} n_3$.
Comment: 26 pages, 35 figures

الوصول الحر: http://arxiv.org/abs/2312.03384Test

المؤلفون: Cho, Eun-Kyung, Kim, Minki

مصطلحات موضوعية: Mathematics - Combinatorics

الوصف: In 2011, Henning, L\"{o}wenstein, and Rautenbach observed that the domination number of a graph is bounded from above by the product of the packing number and the maximum degree of the graph. We prove a stronger statement in subcubic graphs: the independent domination number is bounded from above by three times the packing number.
Comment: 9 pages, 3 figures

الوصول الحر: http://arxiv.org/abs/2307.05119Test

المؤلفون: Cho, Byoung Chul, Kim, Dong-Wan, Spira, Alexander I, Gomez, Jorge E, Haura, Eric B, Kim, Sang-We, Sanborn, Rachel E, Cho, Eun Kyung, Lee, Ki Hyeong, Minchom, Anna, Lee, Jong-Seok, Han, Ji-Youn, Nagasaka, Misako, Sabari, Joshua K, Ou, Sai-Hong Ignatius, Lorenzini, Patricia, Bauml, Joshua M, Curtin, Joshua C, Roshak, Amy, Gao, Grace, Xie, John, Thayu, Meena, Knoblauch, Roland E, Park, Keunchil

المصدر: Nature Medicine. 29(10)

مصطلحات موضوعية: Biomedical and Clinical Sciences, Clinical Sciences, Oncology and Carcinogenesis, Cancer, Clinical Trials and Supportive Activities, Lung, Lung Cancer, Clinical Research, Evaluation of treatments and therapeutic interventions, 6.1 Pharmaceuticals, 6.2 Cellular and gene therapies, Humans, Carcinoma, Non-Small-Cell Lung, Lung Neoplasms, Prospective Studies, Protein Kinase Inhibitors, Mutation, Aniline Compounds, ErbB Receptors, Medical and Health Sciences, Immunology, Biomedical and clinical sciences, Health sciences

الوصف: Patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) often develop resistance to current standard third-generation EGFR tyrosine kinase inhibitors (TKIs); no targeted treatments are approved in the osimertinib-relapsed setting. In this open-label, dose-escalation and dose-expansion phase 1 trial, the potential for improved anti-tumor activity by combining amivantamab, an EGFR-MET bispecific antibody, with lazertinib, a third-generation EGFR TKI, was evaluated in patients with EGFR-mutant NSCLC whose disease progressed on third-generation TKI monotherapy but were chemotherapy naive (CHRYSALIS cohort E). In the dose-escalation phase, the recommended phase 2 combination dose was established; in the dose-expansion phase, the primary endpoints were safety and overall response rate, and key secondary endpoints included progression-free survival and overall survival. The safety profile of amivantamab and lazertinib was generally consistent with previous experience of each agent alone, with 4% experiencing grade ≥3 events; no new safety signals were identified. In an exploratory cohort of 45 patients who were enrolled without biomarker selection, the primary endpoint of investigator-assessed overall response rate was 36% (95% confidence interval, 22-51). The median duration of response was 9.6 months, and the median progression-free survival was 4.9 months. Next-generation sequencing and immunohistochemistry analyses identified high EGFR and/or MET expression as potential predictive biomarkers of response, which will need to be validated with prospective assessment. ClinicalTrials.gov identifier: NCT02609776 .

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/1s33k5j3Test

المؤلفون: Kim, Jeongwoo, Cho, Eun-Sun, Paik, Joon-Young

مصطلحات موضوعية: Computer Science - Cryptography and Security

الوصف: Malware detection on binary executables provides a high availability to even binaries which are not disassembled or decompiled. However, a binary-level approach could cause ambiguity problems. In this paper, we propose a new feature engineering technique that use minimal knowledge about the internal layout on a binary. The proposed feature avoids the ambiguity problems by integrating the information about the layout with structural entropy. The experimental results show that our feature improves accuracy and F1-score by 3.3% and 0.07, respectively, on a CNN based malware detector with realistic benign and malicious samples.
Comment: 2pages, no figures, This manuscript was presented in the poster session of The Annual Computer Security Applications Conference (ACSAC) 2020

الوصول الحر: http://arxiv.org/abs/2304.02260Test

المؤلفون: Mok, Seong-Kyun, Cho, Eun-Sun

مصطلحات موضوعية: Computer Science - Cryptography and Security

الوصف: Since buffer overflow has long been a frequently occurring, high-risk vulnerability, various methods have been developed to support spatial memory safety and prevent buffer overflow. However, every proposed method, although effective in part, has its limitations. Due to expensive bound-checking or large memory in taking for metadata, the software-only support for spatial memory safety inherently entails runtime overhead. Contrastingly, hardware-assisted methods are not available without specific hardware assistants. To mitigate such limitations, Herein we propose L4 Pointer, which is a 128-bit pointer extended from a normal 64-bit virtual addresses. By using the extra bits and widespread SIMD operations, L4 Pointer shows less slow-down and higher performance without hardware extension than existing methods.

الوصول الحر: http://arxiv.org/abs/2302.06819Test

المؤلفون: Cho, Eun-Kyung, Choi, Ilkyoo, Kwon, Hyemin, Park, Boram

مصطلحات موضوعية: Mathematics - Combinatorics

الوصف: The following relaxation of proper coloring the square of a graph was recently introduced: for a positive integer $h$, the proper $h$-conflict-free chromatic number of a graph $G$, denoted $\chi_{pcf}^h(G)$, is the minimum $k$ such that $G$ has a proper $k$-coloring where every vertex $v$ has $\min\{deg_G(v),h\}$ colors appearing exactly once on its neighborhood. Caro, Petru\v{s}evski, and \v{S}krekovski put forth a Brooks-type conjecture: if $G$ is a graph with $\Delta(G)\ge 3$, then $\chi_{pcf}^1(G)\leq \Delta(G)+1$. The best known result regarding the conjecture is $\chi_{pcf}^1(G)\leq 2\Delta(G)+1$, which is implied by a result of Pach and Tardos. We improve upon the aforementioned result for all $h$, and also enlarge the class of graphs for which the conjecture is known to be true. Our main result is the following: for a graph $G$, if $\Delta(G) \ge h+2$, then $\chi_{pcf}^h(G)\le (h+1)\Delta(G)-1$; this is tight up to the additive term as we explicitly construct infinitely many graphs $G$ with $\chi_{pcf}^h(G)=(h+1)(\Delta(G)-1)$. We also show that the conjecture is true for chordal graphs, and obtain partial results for quasi-line graphs and claw-free graphs. Our main result also improves upon a Brooks-type result for $h$-dynamic coloring.
Comment: 20 pages, 1 figure

الوصول الحر: http://arxiv.org/abs/2302.06125Test

المؤلفون: Cho, Eun-Kyung, Choi, Ilkyoo, Lidický, Bernard

مصطلحات موضوعية: Mathematics - Combinatorics

الوصف: The famous Wegner's Planar Graph Conjecture asserts tight upper bounds on the chromatic number of the square $G^2$ of a planar graph $G$, depending on the maximum degree $\Delta(G)$ of $G$. The only case that the conjecture is resolved is when $\Delta(G)=3$, which was proven to be true by Thomassen, and independently by Hartke, Jahanbekam, and Thomas. For $\Delta(G)=4$, Wegner's Planar Graph Conjecture states that the chromatic number of $G^2$ is at most 9; even this case is still widely open, and very recently Bousquet, de Meyer, Deschamps, and Pierron claimed an upper bound of 12. We take a completely different approach, and show that a relaxation of properly coloring the square of a planar graph $G$ with $\Delta(G)=4$ can be achieved with 9 colors. Instead of requiring every color in the neighborhood of a vertex to be unique, which is equivalent to a proper coloring of $G^2$, we seek a proper coloring of $G$ such that at most one color is allowed to be repeated in the neighborhood of a vertex of degree 4, but nowhere else.
Comment: 9 pages

الوصول الحر: http://arxiv.org/abs/2212.10643Test