• Journal of Information Display
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• v.9 no.1
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• pp.6-13
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• 2008

Mobile phones use the embedded memory in LDI (LCD Driver IC). In memory accessing mode, data overlapping phenomenon can occur. These days, various contents such as DMB, Camera, Game are merged to phone. Accordingly, with more data transmission, there would be more data overlapping phenomenon in memory accessing mode. Human eyes perceive this data overlapping phenomenon as simply horizontal line noise. The cause of the data overlapping phenomenon was analysed in this paper. The data overlapping phenomenon can be changed by the speed of data transmission between the host and LDI. The optimum memory accessing position can be defined. This paper proposes a new algorithm for avoiding data overlapping.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.12
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• pp.618-629
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• 2007

In this paper, we propose an effective memory test environment, called a virtualized kernel, for 64bit multi-core computing environments. The term of effectiveness means that we can test all of the physical memory space, even the memory space occupied by the kernel itself, without rebooting. To obtain this capability, our virtualized kernel provides four mechanisms. The first is direct accessing to physical memory both in kernel and user mode, which allows applying various test patterns to any place of physical memory. The second is making kernel virtualized so that we can run two or more kernel image at the different location of physical memory. The third is isolating memory space used by different instances of virtualized kernel. The final is kernel hibernation, which enables the context switch between kernels. We have implemented the proposed virtualized kernel by modifying the latest Linux kernel 2.6.18 running on Intel Xeon system that has two 64bit dual-core CPUs with hyper-threading technology and 2GB main memory. Experimental results have shown that the two instances of virtualized kernel run at the different location of physical memory and the kernel hibernation works well as we have designed. As the results, the every place of physical memory can be tested without rebooting.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.6
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• pp.89-95
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• 2008

In this paper, we designed a low power face detection hardware and analysed its power consumption. The face detection hardware was fabricated using Samsung 0.18um CMOS technology and it can detect multiple face locations from a 2-D image. The hardware is composed of 6 functional modules and 11 internal memories. We introduced two operating modes(SLEEP and ACTIVE) to save power and a clock gating technique was used at two different levels: modules and registers. In additional, we divided an internal memory into several pieces to reduce the energy consumed when accessing memories, and fully utilized low power design option provided in Synopsis Design Compiler. As a result, we could obtain 68% power reduction in ACTIVE mode compared to the original design in which none of the above low power techniques were used.