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フィールドにおけるテスト印加と低電力論理BISTに関する研究
Get PDF九州工業大学博士学位論文 学位記番号:情工博甲第289号 学位授与年月日:平成26年3月25日1. INTRODUCTION||2. PRELIMINARY||3. BIST-BASED FIELD ROTATING TEST FOR AGING-INDUCED FAULT DETECTION||4. TEST POWER REDUCTION FOR LOGIC-BIST||5. SUMMARYAdvances in semiconductor process technology have resulted in various aging issues in field operation of Very Large Scale Integration (VLSI) circuits. For example, HCI (Hot carrier injection), BTI (Bias Temperature Instability), TDDB (Time Dependent Dielectric Breakdown) are well-known aging phenomena, and they can increase the circuit delay resulting in serious reliability problems. In order to avoid system failures caused by aging, recent design usually sets a certain timing margin in operational frequency of the circuit. However, it is difficult to determine the size of the proper timing margin because of the difficulty of prediction of its aging speed in actual use that is related to operational environment. Pessimistic prediction may result in performance sacrificing although it will improve the reliability of the system. BIST-based field test is a promising way to guarantee the reliability of the circuit through detecting the aging-induced faults during the circuit operation. However, the field test has a limitation on test application time, which makes it difficult to achieve high test quality. Therefore an effective test application method at field is required. In addition to the requirement of short test application time, the BIST-based field test requires performing at-speed testing in order to detect timing-related defects. However, it is well known that power dissipation during testing is much higher than that in normal circuit operation. Because excessive power dissipation causes higher IR-drop and higher temperature, it results in delay increase during testing, and in turn, causing false at-speed testing and yield loss. While many low power test methods have been proposed to tackle the test power issue, inadequate test power reduction and lower fault coverage still remain as important issues. Moreover, low power testing that just focuses on power reduction is insufficient. When the test power is reduced to a very low level, a timing-related defect may be missed by the test, and a defective circuit will appear to be a good part passing the test. Therefore, appropriate test power control is necessary though it was out of considering in the existing methods. In this dissertation, we first proposed a new test application to satisfy the limitation of short test application time for BIST-based field test, and then we proposed a new low power BIST scheme that focuses on controlling the test power to a specified value for improving the field test quality. In chapter 3, a new field test application method named “rotating test” is presented in which a set of generated test patterns to detect aging-induced faults is partitioned into several subsets, and apply each subset in one test session at field. In order to maximize the test quality for rotating test, we proposed test partitioning methods that refer to two items: First one aims at maximizing fault coverage of each subset obtained by partitioning. Second one aims at minimizing the detection time interval of all faults in rotating test to avoid system failures. Experimental results demonstrated the effectiveness of the proposed partitioning methods. In chapter 4, we proposed a new low power BIST scheme which can control the scan-in power, scan-out power and capture power while keeping test coverage at high level. In this scheme, a new circuit called pseudo low-pass filter (PLPF) is developed for scan-in power control, and a multi-cycle capture test technique is employed to reduce the capture power. In order to control scan-out power dissipated by test responses, we proposed a novel method that selects some flip-flops in scan chains at logic design phase, and fills the selected flip-flops with proper values before starting scan-shift operation so as to reduce the switching activity associated with scan-out. The experimental results for ISCAS-89 and ITC-99 benchmark circuits show that significant scan-in power reduction rate (the original rate of 50% is reduced to 7~8%) and capture power reduction rate (the original rate of 20% is reduced to 6~7%) were derived. With the scan-out controlling method, the scan-out power can be reduced from 17.2% to 8.4%, which could not be achieved by the conventional methods. Moreover, in order to control the test power to the specified rate to accommodate the various test power requirements. A scan-shift power controlling scheme was also discussed. It showed the capability of controlling any scan-shift toggle rate between 6.7% and 50%
新規な蛍光基質ペプチド4-メチルクマリン-7-アミドの合成と応用に関する研究
No full text九州工業大学博士学位論文 学位記番号:生工博甲第216号 学位授与年月日:平成26年3月25日Chapter 1. Introduction||Chapter 2. Fluorescent substrates of histone deacetylases (HDACs)||Chapter 3. Synthesis of useful amino acid derivatives for methylated peptides||Chapter 4. Fluorescent substrates of histone methyltransferases (HMTs)||Chapter 5. New fluorescence measuring instrument-EAAS_PD||Chapter 6. Fluorescent substrates of Arg-gingipain for periodontal diseases||Chapter 7. Conclusion
ウシガエル味神経応答に対する浸透圧の効果 －浸透圧効果の時間依存性とタイトジャンクションの物質透過性－
Get PDF九州工業大学博士学位論文 学位記番号:生工博甲第221号 学位授与年月日:平成26年3月25日第1章 序論||第2章 ウシガエル味神経応答に対する浸透圧効果の時間依存性||第3章 浸透圧による味上皮の物質透過性||結
画像からの顕著領域と人物の検出に関する研究
Get PDF九州工業大学博士学位論文 学位記番号:工博甲第365号 学位授与年月日:平成26年3月25日1. General Introduction||2. Saliency detection using combined spatial non-redundancy and local appearance||3. Human detection using LBP-based patterns of oriented edges||4. General Conclusion||5. Appendice
Representation of Classification Functions by Head-Tail Expressions
Get PDF九州工業大学博士学位論文 学位記番号:情工博甲第291号 学位授与年月日:平成26年3月25日1 Introduction||2 Preliminary||3 GeneratingPrefixSum-of-ProductsExpressionsforIntervalFunctions||4 Derivation ofHead-TailExpressions for Interval Functions||5 Head-Tail Expressions for Single-Field Classification Functions||6 Head-TailExpressions forMulti-FieldClassificationFunctions||7 Conclusion and Future Work||Acknowledgements||List of PublicationsPacket classification is used in various network applications such as firewalls, access control lists, and network address translators. This technology uses ternary content addressable memories (TCAMs) to perform high speed packet forwarding. However, TCAMs dissipate high power and their cost are high. Thus, reduction of TCAMs is crucial.
First, this thesis derives the prefix sum-of-products expression (PreSOP) and the number of products in a PreSOP for an interval function. Second, it derives Ψ(n,τ p), the number of n-variable interval functions that can be represented with τp products. Finally, it shows that more than 99.9% of the n-variable interval functions can be represented with ?32 n ? 1? products when n is sufficiently large. These results are useful for fast PreSOP generator and for estimating the size of Ternary Content Addressable Memories (TCAMs) for packet classification.
Second, this thesis shows a method to represent interval functions by using head-tail expressions. The head-tail expressions represent greater-than GT(n : A) functions, lessthan LT(n : B) functions, and interval functions IN0(n : A,B) more efficiently than sum-of-products expressions, where n denotes the number of bits to represent the largest value in the interval (A,B). This paper proves that a head-tail expression (HT) represents an interval function with at most n words in a ternary content addressable memory (TCAM) realization. It also shows the average numbers of factors to represent interval functions by HTs for up to n = 16, which were obtained by a computer simulation. It also conjectures that, for sufficiently large n, the average number of factors to represent n-variable interval functions by HTs is at most 23 n ? 59. Experimental results also show that, for n ? 10, to represent interval functions, HTs require at least 20% fewer factors than MSOPs, on the average.
Third, this thesis presents a method to generate head-tail expressions for single-field classification functions. First, it introduces a fast prefix sum-of-product (PreSOP) generator (FP) which generates products using the bit patterns of the endpoints. Next, it shows a direct head-tail expression generator (DHT). Experimental results show that DHT generates much smaller TCAM than FP. The proposed algorithm is useful for simplified TCAM generator for packet classification.
Finally, this thesis shows methods to simplify rules in TCAMs for packet classification.
First method, it partitions the rules into groups so that each group has the same source address, destination address and protocol. After that, it implifies rules in each group by removing redundant rules. A computer program was developed to simplify rules among groups. Experimental results show that this method reduces the size of rules up to 57% of the original specification for ACL5 rules, 73% for ACL3 rules, and 87% for overall rules. This algorithm is useful to reduce TCAMs for packet classification. In the second method, we reduce the number of words in TCAM for multi-field classification functions by using head-tail expressions. It presents MFHT, an O(r2)-algorithm to generate simplified TCAMs for two-field classification functions, where r is the number of rules. Experimental results show that MFHT achieves a 58% reduction of words for random rules and a 52% reduction of words for ACL and FW rules. Moreover, MFHT is fast. The methods are useful for simplifying TCAM for packet classification
The Effect and Continuousness of Glow-Discharge on a Titanium Surface
No full textThe initial adhesion of cells to the implant surface and the subsequent behavior of the cells are important for their biocompatibility. This study investigated the continuousness of the effects of glow-discharge (GD) treatment on the adhesion of cells to titanium.
Polished titanium plates (30 mm in diameter, 2 mm in thickness) were treated with GD. Human gingival fibroblast (hGF) cells were seeded on each treated sample. After 6 h of culture, cells were fixed and stained with TRITC-phalloidin to count the number of attached cells. After 24 h of culture, the cells were fixed and incubated with antibody against vinculin to examine the formation of focal adhesion. Titanium disks were treated using GD in a plasma chamber for 20-240 s. To compare with the effects of ultraviolet (UV) treatment, the titanium disks were exposed to UV for 6-48 h. Untreated titanium disks were used as controls (CON) . The hydrophilic status of the titanium surfaces was analyzed by XPS analysis, and the wettability was examined by the spread of 5 μL of H2O. Titanium disks treated with GD were in the air for 0-6 h after the treatment to examine the continuousness of the effects of GD treatment. The maximum wettability was observed by GD treatment for 120 s, whereas the maximum wettability by UV treatment was observed by the 48 h of UV treatment. The effect of GD decreased by half at 1 h after GD treatment and converged with the CON level at 6 h. The number of hGF cells attached to GD and UV after 6 h of incubation was significantly greater than that attached to CON. The number of vinculin immuno-positive focal adhesion per cell was significantly greater on GD and UV treated disks than on CON disks. Neither the number of attached cells nor focal adhesion formation showed significant differences between GD and UV.
These findings demonstrated that only 2 min of GD treatment on the titanium surfaces caused similar wettability and cell attachment as 48 h of UV treatment. However, the effect of GD treatment disappeared within 6 h in the air. The present study suggests that GD treatment is quite easy but titanium implants treated with GD should be used as soon as possible after GD treatment
Analytical Study of Robustness of a Negative Feedback Oscillator by Multiparameter Sensitivity
Get PDFBACKGROUND:
One of the distinctive features of biological oscillators such as circadian clocks and cell cycles is robustness which is the ability to resume reliable operation in the face of different types of perturbations. In the previous study, we proposed multiparameter sensitivity (MPS) as an intelligible measure for robustness to fluctuations in kinetic parameters. Analytical solutions directly connect the mechanisms and kinetic parameters to dynamic properties such as period, amplitude and their associated MPSs. Although negative feedback loops are known as common structures to biological oscillators, the analytical solutions have not been presented for a general model of negative feedback oscillators.
RESULTS:
We present the analytical expressions for the period, amplitude and their associated MPSs for a general model of negative feedback oscillators. The analytical solutions are validated by comparing them with numerical solutions. The analytical solutions explicitly show how the dynamic properties depend on the kinetic parameters. The ratio of a threshold to the amplitude has a strong impact on the period MPS. As the ratio approaches to one, the MPS increases, indicating that the period becomes more sensitive to changes in kinetic parameters. We present the first mathematical proof that the distributed time-delay mechanism contributes to making the oscillation period robust to parameter fluctuations. The MPS decreases with an increase in the feedback loop length (i.e., the number of molecular species constituting the feedback loop).
CONCLUSIONS:
Since a general model of negative feedback oscillators was employed, the results shown in this paper are expected to be true for many of biological oscillators. This study strongly supports that the hypothesis that phosphorylations of clock proteins contribute to the robustness of circadian rhythms. The analytical solutions give synthetic biologists some clues to design gene oscillators with robust and desired period
Ferrocenylnaphthalene Diimide-Based Electrochemical Detection of Aberrant Methylation in hTERT Gene
Get PDFSince aberrant methylation at CpG sites is linked to the silencing of tumor suppressor genes, DNA methylation analysis is important for cancer diagnosis. We developed ferrocenylnaphthalene diimide (FND), which has two ferrocenyl moieties at the substituent termini, as an electrochemical indicator for hybridized DNA duplexes. In this study, we attempted to detect aberrant methylation of human telomerase reverse transcriptase gene (hTERT), an efficient cancer marker, using FND-based hybridization coupled with electrochemical detection via a multi-electrode chip
Effects of Resin Thickness on the Stress Intensity Factors of Edge-cracked Adhesive Joints
Get PDF2014 15th International Conference on Electronic Packaging Technology (ICEPT 2014), August 12-15, 2014, Chengdu, ChinaThe effects the thickness of epoxy resin on the stress intensity factors (SIFs) of the edge-cracked adhesive joints subjected to external loads are investigated in the current paper. The three-layered joints composed of Silicon, epoxy resin and FR-4.5 are widely seen in the package solutions of CSP/FBGA for electronic devices. Cracks or delaminations from resin-substrate interface or resin-silicon interface are the common failure modes in plastic IC packages. However, it is difficult to determine the exact stress state of a bi-material interface due to the oscillatory singularity. In this paper, the SIFs of the single edge-cracked joints are determined accurately by using the Crack Tip Stress Method. Then, the effects of resin thickness on the SIFs of various edge interface cracks under uniform tension are investigated by varying the resin thickness and crack length. It was found that the SIFs grow with the increment of resin thickness and reach constants when the resin thickness is larger than the width of the joint