The security of Internet of Things (IoT) devices has become a matter of great concern in recent years. The existence of security holes in the executable programs in the IoT devices has resulted in difficult to estimate security risks. For a long time, vulnerability detection is mainly completed by manual debugging and analysis, and the detection efficiency is low and the accuracy is difficult to guarantee. In this paper, the mainstream automated vulnerability analysis methods in recent years are studied, and a vulnerability detection algorithm based on symbol execution is presented. The detection algorithm is suitable for lightweight applications in small and medium-sized IoT devices. It realizes three functions: buffer overflow vulnerability detection, encryption reliability detection and protection state detection. The robustness of the detection algorithm was tested in the experiment, and the detection of overflow vulnerability program was completed within 2.75 seconds, and the dete.....

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A new analytical method based on vortex-assisted liquid-liquid microextraction with back extraction (VALLME-BE) coupled with high performance liquid chromatography was developed for the simultaneous determination of antidiabetic drugs; repaglinide, glibenclamide, and glimepiride in water samples. Chromatographic separation was achieved using C18 column (250 ? 4.6 mm ? 5 �m) and methanol-phosphate buffer (pH3.7) in the ratio of 70:30 v/v as a mobile phase at a flow rate of 1 mLmin-1. VALLME-BE was performed using 200 ?L of n-octane dispersed into the aqueous sample (10 mL) with the aid of vortexing agitation. Then, the analytes were back-extracted from the organic solvent to 0.05 M NaOH (40 �L). Under these conditions, enrichment factor of 155-fold was achieved. The developed VALLME-BE method showed excellent linearity in the range of 30 to 1000 �gL-1 with limit of detection (LOD) of 0.41-1.66 �gL-1 and limit of quantification (LOQ) of 1.38-5.54. 41-1.66 �gL-1. VALLME-BE was a.....

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The genus Pulicaria belongs to the Asteraceae family, consists of ca. 100 species with a di-stribution from Europe to North Africa and Asia, particularly around the Mediterranean. The Pulicaria essential oils were recognised to possess considerable biological activities with a varied chemical composition. This article aims to overview the medicinal uses, chemical compositions, and biological activities of Pulicaria essential oils considered as a medicinal plant, widely used as traditional herbal medicines in the treatment of various diseases. The data were collected from the scientific electronic databases including SciFinder, Sco-pus, Elsevier, PubMed, and Google Scholar. A total of sixteen Pulicaria species have been reported for their essential oils and biological activities. It can be observed that the major components were carvotanacetone, ?-pinene, 4-terpineol, ?-caryophyllene, and cis-chyr-santhenol. Pharmacological studies indicated that the essential oils exhibited antioxidant.....

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Last year (2020) has been a challenging year for many sectors, including the education sector that was forced to adapt to new uncertainties. During the COVID-19 pandemic, students had to rely on their gadgets and the Internet for online learning. As a measure of cultivating technology in teaching English as a Second Language (ESL) during the global crisis, Video log (Vlog) was used as a learning tool among the undergraduate students of various disciplines. Vlog served as a medium for students to convey their ideas and experience as these students needed to record themselves in a video. They would actively spend time preparing materials and practicing speeches. This study uses secondary data collected in early 2021. Hence, it covers most of the data in COVID-affected 2020, especially since the Vlog assessment was implemented in September 2020 for the undergraduates who took the English Proficiency paper. The study aims at examining the use of Vlog as a speaking learning tool and the cha.....

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Previous studies [Langmuir, 2014, 30, 21, 6057?6063, Phys. Chem. Chem. Phys., 2017,19, 23869?23877] have shown that surfactants bearing highly-methylated alkyl tails (so-called ?hedgehog? groups) are able to reduce the limiting surface tension at the aqueous critical micelle concentration (CMC) to ?CMC ~24 mN m?1, which is considerably lower than for common n-alkyl tail surfactants (30?40 mN m?1). In the quest to develop even more effective and efficient non-fluorinated surfactants, this study introduces new amphiphiles having double and triple hedgehog tails and examines relationships between surfactant structure and aqueous solution properties. Of particular interest are links between ?CMC, the effective hydrophobic-tail layer density (?layer) and total number of carbon and silicon atoms in the hydrophobic tails (NC+Si). Interestingly, ?CMC is seen to depend on ?layer rather than NC+Si, and ?layer ~0.63 g cm?3 appears to be an optimal surface layer density for promoting low ?CMC. For.....

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The study aims to understand how value is added by higher education institutions (suppliers), and preschools (service providers) in the preschool educational supply chain. Based on the qualitative methodology, 14 group interviews with preschool pre-service teachers and 9 individual interviews with the Head of Academic Programs from the upstream supply chain were performed. In addition, 23 group interviews with preschool teachers and 8 group interviews preschool operators from the downstream supply chain were conducted to verify the data obtained. The results showed active collaboration, frequent dialogues, close discussion and information sharing between the members of preschool education supply chain for the value creation of preschool teachers. The study implies that a structured and long-term relationship should be established between all the members of preschool educational supply chain so that children, the end-user of this system, will gain the best value possible. For future res.....

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This work sets out to examine the validity and reliability of the Mathematical Modeling Attitude Scale (MMAS), a instrument measuring teachers? attitude towards mathematical modeling. A cross-sectional survey research was utilised to describe the validity and reliability of the MMAS. The population of the present study focused on Malaysian mathematics teacher in primary and secondary schools (N = 171) and this was achieved using convenience sampling. Exploratory factor analysis (EFA), confirmatory factor analysis (CFA) and Rasch analysis were utilised in analysing the data in the present work. EFA revealed that the data from the teachers had a four-factor structure: constructivism, relevance and real-life, understanding and motivation and interest. The CFA confirmed that the model fit indices established the four-factor structure of the first and second-order model. Although the Rasch analysis generally supported the finding of EFA and CFA, there was still room for improvement in terms.....

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Several instruments that measure the teaching, learning, and assessment quality have been developed and published. However, a psychometrically sound instrument to measure teaching, learning, and assessment quality in early childhood care and education that suitable for the Malaysian context needs to be validated. Therefore, this study aimed to validate on teaching, learning, and assessment quality in early childhood care and education instrument, which contains 68 items. The sample comprised 3,498, selected by stratified random sampling from a population of all Malaysian kindergarten teachers. Data were analyzed based on the Polytomous Item Response Theory (IRT) using the Xcalibre software. Samejima's Graded Rating Model (SRGM) was found to be the fit model with the data. Unidimensionality assumption and local independence were tested using the exploratory factor analysis and were fulfilled. The instrument?s reliability was overall very good (?=0.966) and the construct validity was als.....

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This study developed and used a mobile Augmented Reality (AR) reading kit to help preschool students recognize alphabets and read simple words more effectively. This study was based on the quantitative approach involving an experimental methodology that used a one-group pretest-posttest design. In this study, the variables of interest to be measured were students' reading skills, motivation, and self-learning. The learning treatment involved a series of reading sessions using the novel learning application that spanned three weeks, with each session lasting for two hours. The sample of this study comprised 60 preschool students, whose ages ranged from four to six, who were selected from three different preschools. The effectiveness of the novel-reading kit was evaluated in terms of students' learning performance, learning motivation in reading, and self-learning. The data for the former were gathered from pre-testing and post-testing. At the same time, a survey was administered to the .....

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This study aimed to validate the instrument for Successful Person on Quality of Early Childhood and Care Education (ECCE). The validation of the constructs was carried out in two phases, firstly, using the Rasch Measurement Model (RMM) and secondly using the Confirmatory Factor Analysis (CfA). The RMM to determined validity, reliability, polarity and fitness of the items and CFA for measurement model by using Win steps software and AMOS. Results from the RMM analysis showed that the reliability and separation of the items and the persons are high. Polarity of the items show that there were 26 items that measured other constructs, and the items were dropped and retained 67 items. Meanwhile, from CFA the measurement model was fitted and accepted; Chi-square/df =2.04 (.90), and PNFI=.84 (>.50). In the regard, the scale was successful for psychometric standard, valid, reliable and stable. ? 2021. All Rights Reserved...

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