172 research outputs found
Initial trust establishment for personal space IoT systems
University of Technology Sydney. Faculty of Engineering and Information Technology.Internet of Things (IoT) is becoming a reality with innovative applications, and IoT platforms have been developed to transfer technologies from research to business solutions. With IoT applications, we have greater control over personal devices and achieve more insights into the resource consumption habits; business processes can be streamlined; people are also better connected to each other. Despite the benefits derived from the IoT systems, users are concerned about the trustworthiness of their collected data and offered services. Security controls can prevent user’s data from being compromised during transmission, storage or unauthorized access, but do not provide a guarantee against the misbehaved devices that report incorrect information and poor services or avoid conducting a common task. Establishing trust relationship among devices and continuously monitoring their trust is the key to guarantee a reliable IoT system and hence mitigate user’s concerns.
In this dissertation, we propose and investigate a novel initial trust establishment architecture for personal space IoT systems. In the initial trust establishment architecture, we propose a trust evidence generation module based on a challenge-response mechanism to generate the trust evidence relying on the device’s responses to the challenges, a trust knowledge assessment module to obtain the knowledge about the device from the generated trust evidence, and a trust evaluation scheme to quantify the initial trust level of the devices. We design and investigate a challenge-response information design to determine feasible designs of the challenge-response mechanism that ensure meaningful and related trust knowledge about the device’s trustworthiness captured from the challenge-response operations. A new trust-aware communication protocol is designed and implemented by incorporating the proposed initial trust establishment architecture into existing Bluetooth Low Energy (BLE) protocol to demonstrate the feasibility and efficiency of the proposed initial trust establishment architecture in practice.
In this work, we first study building blocks and possible architectures of the IoT and analyze key requirements of an IoT system. Based on the analysis, we identify the critical role of the initial trust establishment model and the challenges of establishing initial trust in IoT systems due to the lack of knowledge for the trust assessment to work. To address the challenges, we propose a novel initial trust establishment architecture that can generate trust evidence for assessing the initial trust level of new devices by conducting challenge-response operations within a limited time window before they are admitted to the system.
We propose three new initial trust establishment models based on the proposed architecture. An implicit relationship between the responses and the challenges is assumed for the system to judge the initial trustworthiness of the devices. The first model assesses the initial trust value based on a probability associated with the device’s behavior captured from the challenge-response process. The second model investigates the initial trust value based on a binary outcome set, and the third model quantifies the initial trust level based on a multiple-component outcome set from the challenge-response process.
Subsequently, we propose the challenge-response information design where the challenge-response process is investigated and designed to determine the information space of the challenger’s view on its environment so that the challenge can invite relevant responses from the target environment. Based on the design of the challenge-response mechanism, the system can capture meaningful trust knowledge about the devices from challenge-response operations at their admission phase. We finally design and implement the initial trust-aware BLE protocol which incorporates the proposed initial trust establishment architecture into the existing BLE protocol. The simulation results show the efficiency, feasibility, and dependability of using initial trust-aware BLE protocol for building a trustworthy personal space IoT systems.
The novelty of this research lies in assessing the devices’ initial trust level within a limited time window, before their admission to the personal space IoT system, without requiring prior experience or recommendations. The major contribution of this thesis is that it helps the IoT business solution providers to build secure and trustworthy IoT systems by admitting dependable devices, monitoring the trust of admitted devices, detecting maligned devices, and building long-term trust among. As a result, it mitigates the user’s concerns about the trustworthiness of IoT systems and encourages broader adoption of IoT applications
Factors Affecting the Perception of Happiness among Teachers in Vietnam
Vietnam is in the process of implementing education reforms in which teachers play a crucial role in determining success. This study aims to identify the main factors influencing the perception of happiness at work of Vietnamese teachers during the period of educational reform. In any period, teachers are always considered as being the force behind the success of education. Therefore, teachers' happiness is the most vital factor to be taken into consideration when educating students. Identifying the factors that affect teachers' happiness at work is the key to improving their teaching quality and quality of life. This study was conducted to investigate the factors affecting the perceived happiness of secondary school teachers in Vietnam today, thereby objectively assessing the emotional status of teachers in Vietnam in relation to the work they are doing. The results are as follows: 1) Teachers face a lot of pressure from many sides; 2) There is still a large percentage of teachers who do not really attach importance to the teaching profession; 3) State policies have not helped teachers feel secure in their professional activities; 4) Teacher capacity still needs to be greatly improved; 5) It is necessary to strengthen the connection between teachers, educational leaders, policy makers, school administrators and colleagues. This study uses descriptive statistics to present the research results. The survey was carried out in September 2021
HIGH SCHOOL TEACHERS’ AND STUDENTS’ CHALLENGES OF ONLINE INSTRUCTION IN READING CLASSES
Research into online instruction as an alternative to traditional teaching has indicated its role in facilitating student learning with the use of technology in times of COVID-19 pandemic. However, an intriguing question is how to conduct this mode of teaching English reading within the Vietnamese context. In Vietnam, little information has examined the challenges that high school teachers and students encountered in implementing online English reading classes to meet the needs and interests of the student and facilitate instructional practices. This study is therefore aimed to look into this area of interest. A mixed-methods study was used with fifty teachers and one hundred high school students. Data were collected from questionnaires and semi-structured interviews. The findings show that online instruction in reading classes challenged teachers and students to use technology, prepare lesson contents, and assess student comprehension. Implications are provided to teachers and students for the sake of the quality of online instruction. Article visualizations
Study on the effect of processing methods on the total polyphenol, 2,3,5,4’-tetrahydroxystilben-2-O-β-D-glucoside, and physcion contents in Fallopia multiflora Thunb. Haraldson root
This study investigated the changes in the ingredients in Fallopia multiflora Thunb. Haraldson (FMT) root after processing it with different methods such as soaking, stewing, and steaming or combined methods. The total polyphenol, 2,3,5,4′-tetrahydroxystilben-2-O-β-D-glucoside (THSG), and physcion contents in FMT products after processing were determined using high-performance liquid chromatography (HPLC) and ultraviolet-visible (UV-VIS) methods. The results demonstrated that the processing method and time significantly affected the contents of polyphenol, THSG, and physcion. The physcion and total polyphenol content increased or decreased during processing depending upon the processing time, while the THSG content gradually decreased with an increase in the processing time. The content of physcion (a substance that can cause liver toxicity) was analysed, and the suitable conditions for processing of the FMT products were determined as initial soaking in rice swill for 24 h and subsequent stewing with black beans and water for 12 h
Assessing student learning in selected social sciences and humanities undergraduate programmes at universities in the UK and Vietnam: a comparative case study
This research study investigates the similarities and differences in assessment policy, perspectives and practices in relation to student learning, desirable graduate outcomes and lifelong learning (LLL) in two departments with similar disciplines: Sociology and Social Policy and English Studies of the Midlands University (MU) – UK and Sociology and English Linguistics and Literature of the Ho Chi Minh City University (HCMU) – Vietnam. The study’s conceptual framework was developed from research literatures on assessment, mainly David Boud’s framework of sustainable assessment or assessment for longer term learning, as the framework for data analysis. The methodology is a comparative case study, and the methods include using semi-structured interviews with 22 staff in both cases, four student focus groups, an action-based intervention at the English department of the HCMU, and document analysis. The similarities and differences across the comparative cases are explained on the basis of the economic, socio-cultural and HE contexts, while Boud’s framework is reframed theoretically and operationally for these contexts, and as a guide to improving practices.
The data shows that although more elements of Boud’s framework were found in the MU than the HCMU, assessment in both cases was an imperfect realisation of this framework. The argument is made that this framework can offer a good vision for the two cases to aim at in terms of changes in their assessment perspective and practices, but the framework itself should also be reframed with contextual and cultural features of assessment, as well as the development of human capabilities and functionings in order to encompass a fuller range of educational goals. It is concluded that above all assessment should support not only learning at university but also expansive rather than reductive LLL
When Vaccine Uncertainty Prevails: Association Between Online Social Influence and COVID-19 Vaccine Intentions
Guided by the integrative model of behavioral prediction and the social identity of deindividuation effects model, this study used an online experiment (N = 322) to test a moderated-mediation model that linked exposure to user comments posted to COVID-19 vaccine news stories and vaccine intentions. The study was conducted in Vietnam when the Delta variant of COVID-19 spread to the country and the efficacy and side effects of the COVID-19 vaccine were controversial in the news. Results showed that, compared with vaccine-hesitancy comments, vaccine-acceptance comments significantly increased vaccine intentions through injunctive norms, response efficacy, and attitudes. This indirect association was only significant among participants who perceived commenters as in-group members. Compared with vaccine-hesitancy comments, a mixture of comments that featured both acceptance and hesitancy significantly increased perceived norms, perceived efficacy, and attitudes. Further, comments significantly changed participants’ perceived norms, perceived efficacy, and attitudes compared with the news stories. Theoretical and practical implications are presented
The Current Status of Secondary School Teacher’s Perception of Happiness in Nam Dinh Province during the Implementation Period of the 2018 General Education Program
In the current context of a major revolution in the Vietnamese education system, teachers’ perception of happiness makes an important criterion in evaluating effectiveness of the changes made to educational programs. The initial investigation of the positive effects of this renovation was conducted on the scale of Nam Dinh province and the results show multidimensional sources of information. In addition to positive information, there is still information that raises many questions for leaders to pay attention to. The outcome of the investigation suggests the evaluation of “The job is meaningful” is 3.10 out of 5 points, which is the lowest in assessment criteria. Meanwhile, the rates for “Completely disbelieve” and “Slightly disbelieve” in happiness of their profession in the future take up a large proportion (24.4%). However, other criteria namely “Being satisfied with current position” and “Feeling motivated with the job” received higher evaluation scores, respectively 4.05/5 points and 4.11/5 points. Via the results of the research, the author is looking forward to appropriate actions taken by the Ministry of Education and Training of Vietnam with a view to enhancing the perception of happiness among teachers
PREPARATION AND FTIR STUDIES OF PMMA/PVC POLYMER BLENDS, PVC-g-PMMA GRAFT COPOLYMERS AND EVALUATING GRAFT CONTENT
This study presents the qualitative and quantitative analyses of Fourier Transform Infrared (FTIR) spectra of poly(methyl methacrylate)/poly(vinyl chloride) blends (PMMA/PVC), as well as PVC-g-PMMA graft copolymers. Graft copolymerizations of methyl mathacrylate (MMA) onto PVC macromolecules were carried out mixture of cyclohexanone/N,N-dimethylformamide as solvents, dibenzoyl peroxide as initiator and nitrogen medium. FTIR spectra of PMMA/PVC blends showed that there were molecular interactions between C=O groups of PMMA and C-Cl groups of PVC. Assignments of infrared absorption bands for specific groups of PMMA/PVC blends have been contributed. Using regression method, linear calibration curve between PMMA mole content and peak areas of C=O groups in FTIR spectra of the blends has been found when C=O peak areas were multiplied by an appropriate factor. PMMA grafted content and total PMMA formed content in PVC-g-PMMA graft copolymers have been evaluated. The results showed that grafted PMMA content was increased since PVC was initiatly dechlorinated by NaOH solution. The grafted PMMA content and total formed PMMA content were 5.05 wt.% and 11.25 wt.% respectively when MMA monomers were grafted onto neat PVC and modified PVC molecules
Modification of natural zeolite by salt to treat ammonia pollution in groundwater
Treating ammonium pollution in ground water by natural zeolite after being modificated to the Naform (Z-Na) is the new way of research that scientists interested in. The experiment results showed that, at pH 6, the efficient of treating ammonium in ground water is the highest. The efficient of treating increase rapidly in the first 5 minutes and remain stable after that. Higher concentration of the Z-Na will increase the treating coefficient of the process. With a water sample that has CNNH4+= 27 mg/L at first, using CZ-Na=13g/L and after 5 minutes, the concentration of ammonium in water was declined to 1mg/L, passed the Vietnamese standard for ground water (QCVN 09:2015- MT/BTNMT). The treating coefficient is 96.30%, the adsorption capacity is 2.07 mg N-NH4 +/1g ZNa. The loaded Z-Na was regenerated using 2g/L NaOH solution, the ammonium recovery ratio exceeded 92%. This means the reuse of Z-Na for ammonium adsorption is very high. The results of the experiment with groundwater samples in Phu Xuyen district, Ha Noi have a concentration of 53 mg/L. In conclusion, Z-Na material is perfectly fit for purpose of treating ammonium in ground water because of it low price, safety, easily to imitate and high efficiency.Xử lí ô nhiễm amoni trong nước ngầm bằng vật liệu zeolite tự nhiên được biến tính bằng muối ăn (Z-Na) là một hướng nghiên cứu mới, được các nhà khoa học rất quan tâm. Kết quả thí nghiệm cho thấy, tại pH 6 thì hiệu quả xử lí amoni trong nước là tốt nhất. Hiệu quả xử lí amoni trong nước tăng rất nhanh trong 5 phút đầu tiên xử lý. Càng tăng nồng độ Z-Na thì hiệu quả xử lí amoni càng cao. Với dung dịch nước ban đầu có nồng độ amoni tính theo nitơ (N-NH4 +) nhỏ hơn 27 mg/L và nồng độ vật liệu Z-Na sử dụng là 13g/L thì nước sau xử lí có nồng độ nhỏ hơn 1mg N-NH4 +/L, đạt QCVN 09-MT:2015/BTNMT, hiệu suất xử lí đạt 96,30%, dung lượng hấp phụ cực đại đạt 2,07 mg NNH4 +/1g Z-Na. Vật liệu Z-Na sau khi xử lý được nghiên cứu giải hấp bằng dung dịch NaOH với nồng độ 2g/L cho thấy hiệu quả giải hấp đạt 92% lượng amoni được hấp phụ. Điều này chứng tỏ khả năng tái sử dụng của vật liệu Z-Na cho hấp phụ amoni là khá cao. Kết quả nghiên cứu đã được thử nghiệm xử lý với mẫu nước ngầm tại huyện Phú Xuyên, Hà Nội có nồng độ N-NH4 + là 53 mg/L. Vì vậy, vật liệu Z-Na hoàn toàn có thể ứng dụng vào thực tiễn để xử lý amoni trong nước ngầm rất an toàn, dễ thực hiện và hiệu quả cao
A Review of Tertiary Palynomorph Assemblage in Cuu Long Basin: Case Study of Palynomorphs in Miocene
Tertiary deposits in Cuu Long Basin are very important because they contain fossil fuels such as oil and gas. More than 50% of oil and gas has been produced in Vietnam from Cuu Long Basin. Palynology is used as a valuable tool to support for depositional and age interpretation as well as well correlation
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