• IEMEK Journal of Embedded Systems and Applications
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• v.5 no.3
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• pp.128-135
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• 2010

Recently complexity of embedded software cause to be used real-time operating system (RTOS) to implement various functions in the embedded system. And also, according to requirement of complex functions in embedded systems, the number as well as complexity of tasks get increased continuously. In case that many tasks collaborated in a microprocessor, context switching time between tasks is a overhead waisting a CPU resource. Therefore the time of task context switching is an important factor that affects performance of RTOS. In this paper, we concentrate on the improvement of task context switch for reducing overhead and achieving fast response time in RTOS. To achieve these goal, we suggest multiple register files and task context switching algorithm. By reducing the context switch overhead, we try to ease scheduling and assure fast response times in multitasking environment. As a result, the context switch overhead decreased by 8~16% depend on the number of register files, and some task set which are not schedulable with single register file are schedulable due to that decrease with multiple register files.

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.158-164
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• 2008

This study was conducted for raising the considering the dynamical context of mobile phone use environment in the mobile-phone research. For this I identified the characteristic of the mobile phone use. The first characteristic is that the mobile phone is the context sensitive device. Also, it reflects the user's life pattern because it is the very personal device. I defined the context of mobile phone use with the basis on this identification of those characteristics. I referenced the definition, 'situational context', defining the mobile phone use context. Also, I set up the research scope within the user task that is influential from the situational context, I named this kind of task as the 'contextual task'. I developed the Contextual Task Model in this study. I named the model as the 'ESR Model'. The reason that I developed this contextual task model is that this model can help novice designers and designers unfamiliar with an application domain understand the user behavior and user centered design. And also this model can be effective to communicate each other, I identified the user's contextual tasks three kinds of model. First, the Extend Model includes user tasks that related to extending from user physical working space to the virtual level. Second model is Synchronize Model, which includes issues that lesson the blocking when use several functions at a time or sequentially. Third model is Replace Model, which is come from the characteristic of user life pattern to use the mobile phone. Finally, I proposed an application of this model, CIQ. Through the process to make CIQ I proved the effectiveness of this ESR Model.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.286-288
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• 2003

본 논문에서는 real-time환경에서 abnormal task를 자동 검출하여 시스템 overload 및 오 동작을 사전에 검출할 수 있는 방안을 제안한다. 본 논문에서 제안한 방안은 context switching이 발생하는 시점에서 각task들의 cpu 점유율 및 context switching 횟수를 분석하여 비정상적으로 높은 cpu 점유율을 가지는 task와 과도한 context switching을 일으켜 시스템에 overload를 주는 task들을 자동으로 검출한다. 이들 이용하여 신뢰성 있는 real-time시스템 설계 및 구현을 지원할 수 있다.

• Speech Sciences
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• v.10 no.3
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• pp.37-45
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• 2003

This study attempted to determine the effects of a context-based drawing task on the language expression of a severe Wernicke's and Broca's aphasic. The subjects in this study showed a poor auditory comprehension and naming performance. They also showed paraphasia and perseveration. This study focused on improving language expression by a drawing task based on conversation at hand. Ten target words were chosen which were easily drawnable and familiar to the subjects. The results showed that the context-based drawing task was effective on improving the subjects' confrontation naming ability and expressive language ability in terms of explanation of sentences. In addition, the Broca's aphasic showed improved naming ability when the contextual cues were given and he was supposed to spontaneously name words.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.5
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• pp.71-81
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• 2008

In the paper, we designed a context aware task-role based access control system(CAT-RACS) which can control access and prevent illegal access efficiently for various information systems in ubiquitous computing environment. CAT-RACS applied CA-TRBAC, which adds context-role concept for achieve policy composition by context information and security level attribute to be kept confidentiality of information. CA-TRBAC doesn't permit access when context isn't coincident with access control conditions, or role and task's security level aren't accord with object's security level or their level is a lower level, even if user's role and task are coincident with access control conditions. It provides security services of user authentication and access control, etc. by a context-aware security manager, and provides context-aware security services and manages context information needed in security policy configuration by a context information fusion manager. Also, it manages CA-TRBAC policy, user authentication policy, and security domain management policy by a security policy manager.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.434-443
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• 2016

Users can set manually Android phone to do particular tasks on some situations. This type of setting is inconvenient, and also provide with unnecessary services, which don't consider users' situation. In this research, we design and implement a context-aware automatic task setting application. Users can get context-aware service by setting desired tasks based on contexts using this system. We design a language for describing context-action rules, and statically check validity of context-action rules by performing syntax and semantic check.

• Journal of Korean Elementary Science Education
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• v.39 no.3
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• pp.433-448
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• 2020

In this study, the tasks of thermal equilibrium and heat insulation concept were divided into scientific and everyday contexts to analyzed the level of familiarity, feeling of knowing, state curiosity, and state anxiety that students feel in task contexts and their relationship. The subjects of this study were One hundred nine students in sixth grade of elementary schools located in metropolitan cities. The results of this study were as follows. First, there was no difference in the level of feeling of knowing, state curiosity, and state anxiety in the task of scientific and everyday contexts. In the case of familiarity, there was no consistent tendency in the concept of thermal equilibrium and heat insulation. And the group who recognized the task context familiarly had higher feeling of knowing and lower state anxiety than the group who recognized the task context unfamiliarly. Second, familiarity and feeling of knowing showed high positive correlation, state anxiety and familiarity showed negative correlation, and state anxiety and feeling of knowing had also negative correlation. In addition, familiarity had a negative effect on state anxiety, and FOK had a positive effect on state curiosity and a negative effect on state anxiety. There was no significant moderating effect of the task context. Third, in case of state curiosity, the group perceived the knowledge gap was very small had the highest state curiosity, and the group perceived the knowledge gap was very large had the lowest state curiosity. In case of state anxiety, the less the knowledge gap was perceived, the lower the anxiety was triggered. This study broadens our understanding of the learning process and provides implications for effective instruction strategies for students' cognitive and emotional states.

• Journal of Information Processing Systems
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• v.17 no.5
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• pp.867-878
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• 2021

In context awareness and user intention tasks, dataset construction is expensive because specific domain data are required. Although pretraining with a large corpus can effectively resolve the issue of lack of data, it ignores domain knowledge. Herein, we concentrate on data domain knowledge while addressing data scarcity and accordingly propose a multi-channel long short-term memory (LSTM). Because multi-channel LSTM integrates pretrained vectors such as task and general knowledge, it effectively prevents catastrophic forgetting between vectors of task and general knowledge to represent the context as a set of features. To evaluate the proposed model with reference to the baseline model, which is a single-channel LSTM, we performed two tasks: voice phishing with context awareness and movie review sentiment classification. The results verified that multi-channel LSTM outperforms single-channel LSTM in both tasks. We further experimented on different multi-channel LSTMs depending on the domain and data size of general knowledge in the model and confirmed that the effect of multi-channel LSTM integrating the two types of knowledge from downstream task data and raw data to overcome the lack of data.

• School Mathematics
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• v.17 no.3
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• pp.423-446
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• 2015

This study aims to look into the characteristics of argumentation in the task context of 'Monty Hall problem' at a high school probability class. As a result of an analysis of classroom discourses on the argumentation between teachers and second-year students in one upper level class in high school using Toulmin's argument pattern, it was found that it would be important to create a task context and a safe classroom culture in which the students could ask questions and refute them in order to make it an argument-centered discourse community. In addition, through the argumentation of solving complex problems together, the students could be further engaged in the class, and the actual empirical context enriched the understanding of concepts. However, reasoning in argumentation was mostly not a statistical one, but a mathematical one centered around probability problem-solving. Through these results of the study, it was noted that the teachers should help the students actively participate in argumentation through the task context and question, and an understanding of a statistical reasoning of interpreting the context would be necessary in order to induce their thinking and reasoning about probability and statistics.

• Korean Journal of Cognitive Science
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• v.13 no.4
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• pp.9-21
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• 2002

Four experiments were conducted to examine whether maintaining the same conceptual context across study and test would affect performance on a perceptual implicit memory task. The sense-specific theory of priming (Lewandowsky et al., 1989) predicts greater priming from a match in conceptual context across study and test compared with a condition in which the conceptual context is mismatched, whereas the transfer-appropriate-processing view (e.g., Blaxton, 1989) predicts no difference. In experiment 1 and 2, little or no effect of varying context was observed on a implicit task. In experiment 3 and 4, a process-dissociation procedure (proposed by Jacoby, 1991) was used to separate automatic influences from consciously controlled influence in implicit memory, which was measured by Korean word completion task. The results showed that conceptual context effect was observed in consciously controlled parts of implicit memory. These results suggest that only consciously controlled processing parts of implicit memory is sensitive to conceptual context.