• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.566-571
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• 2014

Channel-stacked 3D NAND flash memory is very promising candidate for the next-generation NAND flash memory. However, there is an inherent issue on cell size variation between stacked channels due to the declined etch slope. In this paper, the effect of the cell variation on the incremental step pulse programming (ISPP) characteristics is studied with 3D TCAD simulation. The ISPP slope degradation of elliptical channel is investigated. To solve that problem, a new programming method is proposed, and we can alleviate the $V_T$ variation among cells and reduce the total programming time.

• Journal of Communications and Networks
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• v.10 no.3
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• pp.331-337
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• 2008

In this paper, we investigate survivability in wavelength division multiplexing (WDM) mesh networks and propose a new algorithm called improved shared-path protection (ISPP) to completely tolerate the double-link failures. Compared with previous algorithms for protecting double-link failures, i.e., shared-path protection (SPP) and shared-link protection (SLP), the advantage of ISPP is to allow primary paths and backup paths to share the mixed wavelength-links based on the proposed new rules in which some primary wavelength-links can be changed to mixed wavelength-links, which can be shared by primary paths and backup paths. In addition, some mixed wavelength-links also can be shared by different backup paths for saving resources. Simulation results show that ISPP algorithm performs better in resource utilization ratio and blocking probability than conventional SPP and SLP algorithms.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.11
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• pp.219-225
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• 2013

Program and erase characteristics of the elliptic gate all around (e-GAA) SONOS cell have been studied as the variation of eccentricity of the channel. An analytic program and erase model for the elliptic GAA SONOS cell is proposed and evaluated. The model shows that the ISPP (incremental-step-pulse programming) property is changed non-linearly as the eccentricity of the e-GAA SONOS cell is increased. It is differently from the well known linear relationship for that of 2D SONOS and even 3D circular SONOS cell with program bias. We can find that the simulation results of ISPP characteristics are in accord with the experimental data.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.08a
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• pp.131-135
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• 1998

5.6kbps 의 전송율에서 fixed codebook 으로 ISPP의 dynamic sparse algebraic codebook을 이용한 ACELP 알고리즘을 제안한다. 저전송율에서 음질에 중대한 영향을 미치는 대수적 방식의 고정코드북이 가지는 문제점을 최소화하여 음질의 증진을 꾀하였다. 또한 추가 계산량이 필요없는 U/V 분리기를 도입하여 LSF 보간시 발생하는 천이구간에서의 지연을 최소화하였다. 구현된 5.6 kbps ACELP 는 전화선상의 음질을 시료로 하여 주관적 음질면에서 6.3 kbps MP-MLQ와 동등하였으며 MNRU 15dB에서 약간 낮았다.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.3
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• pp.47-52
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• 2017

This research scrutinizes the data retention characteristics of the MLC NAND Flash Memory instigated by the loss effect of trapped charge when the memory is in the state of program saturation. It is attributed to the threshold voltage saturation phenomenon which engenders an interruption to the linear increase of the voltage in the memory cell. This phenomenon is occasioned by the outflow of the trapped charge from the floating gate to the control gate, which has been programmed by the ISPP (Incremental Step Pulse Programming), via Inter-Poly Dielectric (IPD). This study stipulates the significant degradation of thermal retention characteristics of threshold voltage in the saturation region in contrast to the ones in the linear region. Thus the current study evaluates the data retention characteristics of voltage after the program with a repeated reading test in various measurement conditions. The loss effect of trapped charge is found in the IPD layer located between the floating gate and the control gate especially in the nitride layer of the IPD. After the thermal stress, the trapped charge is de-trapped and displays the impediment of the characteristic of reliability. To increase the threshold saturation voltage in the NAND Flash Memory, the storage ability of the charge in the floating gate must be enhanced with a well-thought-out designing of the module in the IPD layer.

• Genomics & Informatics
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• v.3 no.4
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• pp.142-148
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• 2005

The immune response-related genes have been suggested to be the most favorable genes for positive selection during evolution. Comparing the entire DNA sequence of chimpanzee chromosome 22 (PTR22) with human chromosome 21 (HSA21), we have identified 15 orthologs having indel in their coding sequences. Among them, interferon-${\alpha}$ receptor-1 gene (IFNAR1), an immuneresponse-related gene, is subjected to comparative genomic analysis. Chimpanzee IFNAR1 showed the same genomic structure as human IFNAR1 (11 exons and 10 introns) except the 3 bp insertion in exon 4. The sequence alignment of IFNAR1 coding sequence indicated that 'ISPP' amino acid sequence motif is highly conserved in chimpanzee and other animals including mouse and chicken. However, the human IFNAR1 shows that one proline residue is missing in the sequence motif. The homology modeling of the IFNAR1 structures suggests that the proline deletion in human IFNAR1 leads to the formation of the following ${\alpha}$-helix, whereas two sequential prolines in chimpanzee IFNAR1 inhibit it. As a result, human IFNAR1 may adopt a characteristic structure distinct from chimpanzee IFNAR1. This human specific trait could contribute to specific immune response in the most optimized manner for humans. Further molecular biological studies on the IFNAR1 will help us to gain insights into the molecular implication of species-specific host-pathogen interaction in primate evolution.