In this paper, a tentative Kth order Goldschmidt floating point number Nth root algorithm for K order convergence rate in one iteration is proposed by applying Taylor series to the Goldschmidt square ...root algorithm. Using the proposed algorithm, Nth root and Nth inverse root can be computed from iterative multiplications without division. It also predicts the error of the algorithm iteration. It iterates until the predicted error becomes smaller than the specified value. Since the proposed algorithm only performs the multiplications until the error gets smaller than a given value, it can be used to improve the performance of a floating point number Nth root unit.
DKxanthenes are a class of yellow secondary metabolites produced by myxobacterial genera Myxococcus and Stigmatella. We identified a putative 49.5 kb DKxanthene biosynthetic gene cluster from ...Myxococcus stipitatus DSM 14675 by genomic sequence and mutational analyses.
The cluster consisted of 15 genes (MYSTI_06004-MYSTI_06018) encoding polyketide synthases, non-ribosomal peptide synthases, and proteins with unknown functions. Disruption of the genes by plasmid insertion resulted in defects in the production of yellow pigments. Highperformance liquid chromatography and liquid chromatography-tandem mass spectrometry analyses indicated that the yellow pigments produced by M. stipitatus DSM 14675 might be novel DKxanthene derivatives. M. stipitatus did not require DKxanthenes for the formation of heat-resistant viable spores, unlike Myxococcus xanthus. Furthermore, DKxanthenes showed growth inhibitory activity against the fungi Aspergillus niger, Candida albicans, and Rhizopus stolonifer. KCI Citation Count: 0
항공전자 시스템의 복잡성이 높아짐에 따라 소프트웨어 컴포넌트의 이식성 및 재사용성이 강조되었다. 본 논문에서는 ARINC 653 요구사항을 만족하는 VxWorks 653 운용 환경에서 FACE(The Future Airborne Capability Environment)표준에 적합한 IOSS(Input Output Service Segment) 및 ...TSS(Transport Service Segment)에 대한 구조 설계 방안을 설명한다. IOSS 및 TSS는 각각 다른 파티션에서 독립적으로 동작하게 하여 시/공간 분리 및 다른 소프트웨어의 영향성을 최소화 하였고, 이식성 및 재사용성을 높이기 위해 디자인 패턴 중 전략 패턴을 적용하였다. 또한, IOSS는 Distributed IO Service 구조를 적용하여 외부 인터페이스 서비스를 제공하고, 외부 인터페이스 중 FACE를 적용한 장비의 ARINC 664 P7 인터페이스는 TSS에 배치하여 데이터 이동 경로를 최적화 하였다.
The increasing complexity of avionics systems has emphasized the portability and reusability of software components. In this paper, a structural design method for IOSS (Input Output Service Segment) and TSS (Transport Service Segment) complying with the FACE (The Future Airborne Capability Environment) standard in the VxWorks 653 operating environment that satisfies ARINC 653 requirements is described. IOSS and TSS operate independently in different partitions to minimize time/space separation and the influence of other software, and to increase portability and reusability, strategy patterns among design patterns are applied. In addition, IOSS provides external interface service by applying distributed IO service structure, and among external interfaces, the ARINC 664 P7 interface of FACE-compliant equipment is placed in TSS to optimize the data movement path.
The commonly used Goldschmidt's floating-point divider algorithm performs two multiplications in one iteration. In this paper, a tentative error corrected K'th Goldschmidt's floating-point number ...divider algorithm which performs K times multiplications in one iteration is proposed. Since the number of multiplications performed by the proposed algorithm is dependent on the input values, the average number of multiplications per an operation in single precision and double precision divider is derived from many reciprocal tables with varying sizes. In addition, an error correction algorithm, which consists of one multiplication and a decision, to get exact result in divider is proposed. Since the proposed algorithm only performs the multiplications until the error gets smaller than a given value, it can be used to improve the performance of a divider unit. Also, it can be used to construct optimized approximate reciprocal tables. 부동소수점 나눗셈에서 많이 사용하는 골드스미트 부동소수점 나눗셈 알고리즘은 한 회 반복에 두 번의 곱셈을 수행한다. 본 논문에서는 한 회 반복에 K 번 곱셈을 수행하는 가칭 오차 교정 K차 골드스미트 부동소수점 나눗셈 알고리즘을 제안한다. 본 논문에서 제안한 알고리즘은 입력 값에 따라서 곱셈 횟수가 다르므로, 평균 곱셈 횟수를 계산하는 방식을 유도하고, 여러 크기의 근사 역수 테이블에서 단정도실수 및 배정도실수의 나눗셈 계산에 필요한 평균 곱셈 횟수를 계산한다. 또한 한 번의 곱셈과 판정으로 나눗셈 결과를 보정하는 알고리즘을 제안한다. 본 논문에서 제안한 알고리즘은 오차가 일정한 값보다 작아질 때까지만 반복 연산을 수행하므로 나눗셈 계산기의 성능을 높일 수 있다. 또한 최적의 근사 테이블을 구성할 수 있다.
5단계 파이프라인으로 구성된 기밀성과 무결성이 우수하고 실시간처리가 가능한 128비트 출력 스트림 암호를 개발했다. 개발한 스트림 암호는 ASR 277비트와 SHACAL-2를 통해 128비트 스트림을 만들고 이를 CFB모드 적용한 후 표백처리 과정을 통하여 최종적인 128비트 암호문을 만드는 스트림 암호 알고리즘이다. 스트림 암호의 하드웨어는 ...Verilog HDL을 사용하여 Modelsim 6.5d를 활용하여 기능을 검증하였고, 성능은 Quartus II 12.0을 활용하여 분석했고, Worst Case에서 Max Frequency는 33.34MHz(4.27Gbps)의 빠른 성능을 보여주었다. 이는 무선 인터넷과 센서 네트워크 및 DRM 환경의 속도를 충분히 만족함을 보여준다. 기밀성과 무결성이 우수한 스트림 암호 알고리즘 개발에 본 논문은 매우 유용한 아이디어를 제공하고 있다. We have developed a 128-bit stream cipher algorithm composed of the 5-stage pipeline, capable of real-time processing, confidentiality and integrity. The developed stream cipher is a stream cipher algorithm that makes the final 128-bit ciphers through a whitening process after making the ASR 277 bit and SHACAL-2 and applying them to the CFB mode. We have verified the hardware performance of the proposed stream cipher algorithm with Modelsim 6.5d and Quartus II 12.0, and the result shows that the hardware runs at 33.34Mhz(4.27Gbps) at worst case. According to the result, the new cipher algorithm has fully satisfied the speed requirement of wireless Internet and sensor networks, and DRM environment. Therefore, the proposed algorithm with satisfaction of both confidentiality and integrity provides a very useful ideas. KCI Citation Count: 1
Myxococcus stipitatus DSM 14675는 DKxanthene, melithiazol, phenalamide 등과 같은 생리활성 이차대사산물을 생산하는 점액세균이다. M. stipitatus의 이차대사를 조절하는 전사조절인자를 탐색하기 위하여 M. stipitatus DSM 14675 균주의 유전체에서 Myxococcus xanthus에서 ...이차대사 전사조절인자 유전자로 알려진 hsfA와 MXAN_4899 유전자의 동족체 유전자를조사하여 MYSTI_05929 (hsfA)와 MYSTI_05387 유전자를 발견하였다. 플라스미드 삽입을 통해 M. stipitatus DSM 14675 균주에서 MYSTI_05929 (hsfA) 유전자를 불활성화시켰을 때DKxanthene, melithiazol, phenalamide 생산이 야생형에 비해각각 82.7%, 100%, 60.3% 감소하였다. MYSTI_05387 유전자를 불활성화시켰을 때는 DKxanthene의 생산이 야생형에 비해 12.9% 증가하였으나 melithiazol과 phenalamide 생산은 각각 100%, 69.2% 감소하였다. 따라서 MYSTI_05929 (hsfA)와MYSTI_05387 유전자가 암호화하는 단백질은 M. stipitatus에서이차대사 조절에 관여하는 것으로 보인다. 한편, MYSTI_05929 (hsfA) 유전자는 불활성화되었을 때 S-운동성과 자실체 형성이 결손되어 S-운동성과 자실체 형성에 필수적인 것으로 나타났다. Myxococcus stipitatus DSM 14675 is a myxobacterium that produces bioactive secondary metabolites such as DKxanthene, melithiazol, and phenalamide. To explore transcriptional regulators of secondary metabolism in M. stipitatus, we searched the genome of the M. stipitatus DSM 14675 strain for homologs of the hsfA and MXAN_4899 genes, which are known as secondary metabolism transcriptional regulator genes in Myxococcus xanthus, and discovered the MYSTI_05929 (hsfA) and MYSTI_ 05387 genes. Inactivation of the MYSTI_05929 (hsfA) gene in the M. stipitatus DSM 14675 strain decreased the production of DKxanthene, melithiazol, and phenalamide by 82.7%, 100%, and 60.3%, respectively, compared to the wild type. Inactivation of the MYSTI_05387 gene increased the production of DKxanthene by 12.9% compared to the wild type but decreased the production of melithiazol and phenalamide by 100% and 69.2%, respectively. Thus, the proteins encoded by the MYSTI_05929 (hsfA) and MYSTI_05387 genes appear to be involved in the regulation of secondary metabolism in M. stipitatus. Furthermore, the MYSTI_05929 (hsfA) gene appeared to be essential for S-motility and fruiting body formation, as S-motility and fruiting body formation were defective when inactivated. KCI Citation Count: 0
Phenalamide is a bioactive secondary metabolite produced by Myxococcus stipitatus. We identified a 56 kb phenalamide biosynthetic gene cluster from M. stipitatus DSM 14675 by genomic sequence ...analysis and mutational analysis. The cluster is comprised of 12 genes (MYSTI_04318-MYSTI_04329) encoding three pyruvate dehydrogenase subunits, eight polyketide synthase modules, a non-ribosomal peptide synthase module, a hypothetical protein, and a putative flavin adenine dinucleotide-binding protein. Disruption of the MYSTI_04324 or MYSTI_04325 genes by plasmid insertion resulted in a defect in phenalamide production. The organization of the phenalamide biosynthetic modules encoded by the fifth to tenth genes (MYSTI_04320-MYSTI_04325) was very similar to that of the myxalamid biosynthetic gene cluster from Stigmatella aurantiaca Sg a15, as expected from similar backbone structures of the two substances. However, the loading module and the first extension module of the phenalamide synthase encoded by the first to fourth genes (MYSTI_04326-MYSTI_04329) were found only in the phenalamide biosynthetic gene cluster from M. stipitatus DSM 14675.
Tubulysins are a group of bioactive secondary metabolites from myxobacteria exhibiting strong anticancer activity against various cancer cell lines. In this study, we describe the identification of ...putative tubulysin biosynthetic gene clusters (tubA~tubF) in the genome sequences of two tubulysin-producing myxobacterial strains, Archangium gephyra MEHO_002 and MEHO_004. The inactivation of the putative tubulysin biosynthetic genes resulted in a tubulysin-production defect. The DNA sequences of the A. gephyra MEHO_002 and MEHO_004 tubulysin biosynthetic genes were 97% identical, and the amino acid sequences of the encoded proteins shared a similarity of 97−100%. The nucleotide sequences of the tubulysin biosynthetic gene clusters in MEHO_002 and MEHO_004 were 86% identical to that in Cystobacter sp. SBCb004 known as a tubulysin-producing myxobacterium, and the organization of the clusters was identical except for the lack of a tubZ gene in the clusters in MEHO_002 and MEHO_004. The amino acid sequences of the proteins encoded by each gene were 88-97% similar to those encoded by SBCb004, and the domain compositions of the proteins were also identical. KCI Citation Count: 0
Tubulysins are a group of secondary metabolites produced by myxobacteria that inhibit the function of the eukayotic cytoskeleton. We developed a pair of PCR primers that specifically amplified ...tubulysin biosynthetic genes. Using these primers, eight out of the eighty-one strains of myxobacteria belonging to the Cystobacteraceae family that harbored putative tubulysin biosynthetic genes were screened through PCR analysis. The selected strains included two Archangium gephyra, two Stigmatella sp., two Vitiosangium cumulatum, and two unidentified myxobacteria. LC-MS analysis of the culture extracts from the selected strains revealed that A. gephyra KYC4066 produced putative tubulysin A and B. KCI Citation Count: 1
Using MCF7 breast cancer cells, we tested the anticancer activity of metabolites from 130 strains of myxobacteria newly isolated in South Korea. Of these, three strains whose metabolites had high ...anticancer activity and low cell toxicity were selected and identified by their fruiting body morphology, cell morphology, and 16S rRNA sequence. Strains KYC4030 and KYC4048 were determined to be Myxococcus fulvus, whereas strain KYC4081 was identified as Corallococcus coralloides. We found that metabolites of M. fulvus KYC4048 demonstrated no toxicity in normal cells but specifically induced cancer cell death by suppressing the expression of WNT2B. This discovery highlights the value of assessing the metabolic and biomedical potential of myxobacteria, even those that are already known but were isolated from new areas, and the possible use of metabolites from M. fulvus KYC4048 in cancer treatment. KCI Citation Count: 0
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