• Proceedings of the KIEE Conference
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• 1992.07a
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• pp.365-368
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• 1992

This paper presents an approach to the design of real time task scheduling for a line controller of continuous manufacturing process automation. The line controller has multiprocessor-based architecture with shared memory and is operated by firmware. This firmware contains menu-driven software supporting real-time database management and fuction-block control language. The multitasking line control processor performs the following three functions: 1) interprets the function block control language by virtue of shared memory in the database; 2) invokes an interupt service routine as required by external hardware; 3) detects errors and notifies the user. We propose real time task scheduling method.

• IEMEK Journal of Embedded Systems and Applications
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• v.13 no.4
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• pp.187-194
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• 2018

The operating system for IoT should have a small memory footprint and provide low power state, real-time, multitasking, various network protocols, and security. Although the Zephyr kernel, an operating system for IoT, released by the Linux Foundation in February 2016, has these features but errors generated by the user code can generate fatal problems in the system because the Zephyr kernel adopts a single-space method that both the user code and kernel code execute in the same space. In this research, we propose a space separation method, which separates kernel space and user space, to solve this problem. The space separation that we propose consists of three modifications in Zephyr kernel. The first is the code separation that kernel code and user code execute in each space while using different stacks. The second is the kernel space protection that generates an exception by using the MPU (Memory Protection Unit) when the user code accesses the kernel space. The third is the SVC based system call that executes the system call using the SVC instruction that generates the exception. In this research, we implemented the space separation in Zephyr v1.8.0 and evaluated safety through abnormal execution of the user code. As the result, the kernel was not crashed by the errors generated by the user code and was normally executed.

• Journal of the Ergonomics Society of Korea
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• v.29 no.1
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• pp.17-24
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• 2010

There has been recent interest in intelligent vehicle technologies, such as advanced driver assistance systems (ADASs) or in-vehicle information systems (IVISs) that offer a significant enhancement of safety and convenience to drivers and passengers. However, unsuitable design of HMI (Human Machine Interface) must increase driver distraction and workload, which in turn increase the chance of traffic accidents. Distraction in particular often occurs under a heavy driving workload due to multitasking with various electronic devices like a cell phone or a navigation system while driving. According to the 2005 road traffic accidents in Korea report published by the ROad Traffic Authority (ROTA), more than 60% of the traffic accidents are related to driver error caused by distraction. This paper suggests the structure of vehicle environment for real-time driving behavior monitoring system while driving which is can be used the driver workload management systems (DWMS). On-road experiment results showed the feasibility of the suggested vehicle environment for driving behavior monitoring system.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.6
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• pp.389-397
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• 2015

Recently, wave propagation imaging based on laser scanning-generated elastic waves has been intensively used for nondestructive inspection. However, the proficiency of the conventional software based system reduces when the scan area is large since the processing time increases significantly due to unavoidable processor multitasking, where computing resources are shared with multiple processes. Hence, the field programmable gate array (FPGA) was introduced for a wave propagation imaging method in order to obtain extreme processing time reduction. An FPGA board was used for the design, implementing post-processing ultrasonic wave propagation imaging (UWPI). The results were compared with the conventional system and considerable improvement was observed, with at least 78% (scanning of $100{\times}100mm^2$ with 0.5 mm interval) to 87.5% (scanning of $200{\times}200mm^2$ with 0.5 mm interval) less processing time, strengthening the claim for the research. This new concept to implement FPGA technology into the UPI system will act as a break-through technology for full-scale automatic inspection.

• 한국HCI학회:학술대회논문집
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• 2006.02b
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• pp.233-239
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• 2006

차세대 디지털 방송 기술인 DMB(Digital Multimedia Broadcasting) 지상파서비스가 세계최초로 우리나라에서 시작되었다. 현재 DMB 서비스는 디지털 기기의 다양한 기능들과 더불어 '디지털 컨버전스'를 주도하고 있고, 새 기술을 통한 서비스는 디지털 기기에 대한 사용자의 경험을 한층 풍부하게 해주고 있다. 또한 이러한 제품들은 다양한 기능에 대해서 멀티태스킹을 지원하기 때문에, 사용성, 조작방법 등 여러 측면에서 과거의 제품들과 상당히 많은 차이를 보여준다. 본 논문은 다양한 기능이 통합되고, 멀티태스킹이 되는 제품을 설계하는데 있어 감각양식(Modality) 측면에서 사용자들에게 더 나은 경험을 제공할 수 있도록 하는 방법을 제안한다. 지금까지 모달리티와 인터럽션(Interruption)에 대한 연구는 다중 자원 이론(Multiple resource theory)을 바탕으로 연속적인 과업(Task)를 수행함에 있어서 과업의 감각양식이 충돌할 경우, 사용자에게 인지적인 부담을 준다는 측면에서 이루어져 왔다. 그러나, 본 논문에서는 태스크를 수행함에 있어 멀티태스킹의 지원 여부에 따라서 과업의 감각양식이 다양한 순서를 가지고 사용자에게 인터럽션을 일으킬 때, 사용자의 태스크 수행 능력이나 사용자 만족도에 어떻게 영향을 주는지 알아보고자 한다.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.2
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• pp.199-205
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• 2004

This paper describes the fault diagnosis method to order to construct CIM in complex system with hierarchical structure similar to human body structure. Complex system is divided into unit, item and component. For diagnosing this hierarchical complex system, it is necessary to implement a special neural network. Fault diagnosis system can forecast faults in a system and decide from the signal information of current machine state. Comparing with other diagnosis system for a single fault, the developed system deals with multiple fault diagnosis, comprising hierarchical neural network (HNN). HNN consists of four level neural network, i.e. first is fault symptom classification and second fault diagnosis for item, third is symptom classification and forth fault diagnosis for component. UNIX IPC is used for implementing HNN with multitasking and message transfer between processes in SUN workstation with X-Windows (Motif). We tested HNN at four units, seven items per unit, seven components per item in a complex system. Each one neural network represents a separate process in UNIX operating system, information exchanging and cooperating between each neural network was done by message queue.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2004.11a
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• pp.299-302
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• 2004

본 논문은 OCP(Open Core Protocol)에 호환되는 파이프라인 구조를 가진 시스템 버스와 MPEG 시스템에 적합한 메모리 버스를 갖는 계층 구조를 가지는 새로운 동기 세그먼트 버스를 제안한다. 이 구조는 MPEG 시스템의 모바일 제품에 사용되는 영상 데이터 처리를 위한 메모리 인터페이스에 기반을 둔 버스 구조와 Multi-master와 Multi-slave를 사용하여 고성능의 다중 처리를 위한 양방향 다중 버스 구조(bi-direction multiple bus architecture)를 가진다. 효율적인 데이터 처리를 위하여 파이프라인 stage와 결합된 Master와 Slave의 주소번지가 latency를 결정하며, 시스템의 특성에 따라서 IP 코어를 배치하였다. 제안된 버스는 저 전력 구현을 위하여 세그먼트 버스 구조를 가지고, 멀티미디어 SoC 시스템의 성능 저하 없이 다중 작업이 가능한 구조를 갖는다. Wirability를 고려하여 양방향 구조를 채택하였고, Testablility를 위하여 단방향(uni-direction) 구조와 대체 가능하다. 또한, Local arbiter의 수정만으로 Master의 추가가 가능한 확장 구조를 가진다. Latency를 줄이기 위하여 직접 제어 방식과 단순한 구조의 Central arbiter로 구현되었다.

• Journal of the Ergonomics Society of Korea
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• v.26 no.3
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• pp.67-80
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• 2007

Digital convergence, defined as the creative fusion of once-independent technologies and service, is getting more attention recently. Interruptions among internal functions happen frequently in digital convergence products because many functions that were in separate products are merged into a single product. Multi-tasking and multi-modality are two distinctive features of interruption in digital convergence products, but their impacts to the user have not been investigated yet. This study conducted a controlled experiment to investigate the impacts of multi-tasking and multi-modality on the subjective satisfaction and objective performance of digital convergent products. The study results indicate that multi-tasking and multi-modality have substantial effects individually as well as together. The paper ends with practical and theoretical implications of study results as well as research limits and future research.

• Journal of Korea Game Society
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• v.15 no.4
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• pp.145-156
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• 2015

Existing researches have been limited to one-dimensional analysis of game experience (enjoyment, addictive user, usability). However, we considered to analyze complex sentiments of mobile game users due to diffusion of multitasking in these days. In this study, We focused on 'collective sentiments' of mobile game users and studied 'connected emotions and mental model' of them. To support theoretical assumption, we analyzed social data which reflect intention and unintended behavior of users. As a result, multiple consumption of service, diversified patterns of information recommendation and quest experience based on networking were critical to mobile game UX.

• Journal of the Korean Home Economics Association
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• v.46 no.1
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• pp.103-116
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• 2008

The purpose of this study was to empirically describe the everyday life of middle-aged adults in terms of their time-use activities. From the original '2004 Time dairy' Data, developed by the Korean National Statistical Office (KNOS), 17,684 respondents aged between 35-59 were selected. In order to categorize their activity patterns, work/labour, domestic labour, and spare leisure time were classified according to the action classification system. As a result, four dominant types were found: namely work-leisure, work-oriented, family-oriented, and leisure-oriented activities. Results of multinomial logistic analysis revealed that gender, age, socioeconomic status, job characteristic, and family structure were the major determinants on time-use. Compared with work-leisure, young middle aged women holding a part-time job with less income tended to be involved in a family-centered time use. Dual earners with lower SES status were likely to have work-oriented time schedules. Older men with relatively lower income were more likely to be involved in leisure-oriented activities rather than work-leisure activities. Multitasking behavior was a significant variable in explaining the four different types of time-use. Work-oriented group showed the highest level of time pressure as well as fatigue. Group differences in these measures, however, was not as large as expected.