134 research outputs found
Intelligent Agents: Authors, Makers, and Owners of Computer-Generated Works in Canadian Copyright Law
The central objective of this article is to propose a clarification of copyright law as applied to works created by intelligent agents. In Part I, the concepts of artificial intelligence and intelligent agents are introduced. Part II identifies the challenges that are presented to the tests of originality and authorship in the application of copyright to works generated by intelligent agents. It is argued that works created by intelligent agents may meet the tests of originality and authorship. It is also argued that the con- cepts of ‘‘author’’, ‘‘owner’’, and ‘‘maker’’ are distinct from one another in Canadian copyright law. Part III addresses copyright policy arguments. It is shown that intelligent agents may be authors of works but not owners of copy- right, and that there is no clear candidate who should be designated the maker of works created by intelligent agents. The role of the public domain is also considered, and it is concluded that the best solution is for no copy- right ownership to be vested in anyone. Database protec- tion legislation is examined in Part IV. The paper con- cludes with some suggestions that should be considered as part of the ongoing process of Canadian copyright law reform
A novel implementation of an FPGA-based controller for conducted-noise reduction in randomly switched Dc-Dc converters
This paper proposes a novel implementation of an FPGA-Based controller for conducted-noise reduction in dc-dc converters. The switching noise produced by the converter has been reduced by randomly varying the switching frequency of the converter. Traditionally, the implementation of the switching-mode power supply (SMPS) has been accomplished using analog control circuits. However, the field-programmable gate array (FPGA) is much flexible than analog control circuits, becoming lower cost, and applicable for power supply applications. The implementation of the SMPS has been accomplished using FPGA-based digital controller. Moreover, breadboard has been built-up for testing the effect of using the proposed FPGA-based digital controller for noise reduction in dc-dc converters. Experimental results show that the conducted-noise spectrum has been significantly improved and the noise level has been effectively reduced.24th Annual IEEE Applied Power Electronics Conference and Exposition, APEC 2009; Washington, DC; 15 February 2009 through 19 February 200
FPGA-based design and implementation of spread-spectrum schemes for conducted-noise reduction in DC-DC converters
2009 IEEE International Conference on Industrial Technology - (ICIT) : Churchill, Victoria, Australia, 2009.02.10-2009.02.1
Double-hybrid spread-spectrum technique for conducted-EMI reduction in DC-DC switching regulators with FPGA-based controller
The purpose of this paper is to present a novel technique for conducted-noise reduction in de-de switching regulators. In order to effectively spread the conducted-noise frequency spectrum and, at the same time, attain a satisfactory voltage regulation, two parameters (carrier frequency and pulse position) have been randomized, and the third parameter (duty ratio) has been controlled by a digital compensator. Furthermore, the effect of using the proposed controller on common-mode, differential-mode, and total conducted-noise characteristics of the converter has been experimentally investigated. The converter\u27s performance with using the proposed technique has been experimentally investigated. It is assumed that the implementation technology is a field programmable gate array (FPGA) which is becoming increasingly adopted in industrial electronic applications.INTELEC 2009 - 2009 International Telecommunications Energy Conference : Incheon, South Korea, 2009.10.18-2009.10.2
Crocin from Crocus sativus possesses significant antiproliferation effects on human colorectal cancer cells
Aim: To investigate the anti-proliferative effects of Crocus sativus extract and its major constituent, crocin, on three colorectal cancer cell lines (HCT-116, SW-480, and HT-29). The cell growth inhibition effect was compared to that of non-small cell lung cancer (NSCLC) cells. In addition, Crocus sativus’ effect on non-cancer cells was evaluated. Methods: Using high performance liquid chromatography (HPLC), the purity of crocin and the content of crocin extract were determined. Anti-proliferative effects of Crocus sativus extract and crocin on test cells was evaluated by MTS assay. Results: The purity of crocin was found to be 95.9% and the content of crocin in the extract was 22.9%. Significant concentration-related inhibition effects of the extract on all three colorectal cancer cell lines were observed (P < 0.01). The proliferation was reduced most significantly in HCT-116 cells, to 45.5% at 1.0 mg/ml and to 6.8 % at 3.0 mg/ml. Crocin at 1.0 mM, significantly reduced HCT-116, SW-480, and HT-29 cell proliferation to 2.8%, 52%, and 16.8%, respectively (P < 0.01). Since 3.0 mg/ml Crocus sativus extract contained approximately 0.6 mM crocin, the observed effects suggest that crocin is a major responsible constituent in the extract. Significant anti-proliferative effects were also observed in non-small cell lung cancer cells. However, Crocus sativus extract did not significantly affect the growth of non-cancer young adult mouse colon cells. Conclusion: Data from this study demonstrated that Crocus sativus extract and its major constituent, crocin, significantly inhibited the growth of colorectal cancer cells while not affecting normal cells. Crocus sativus extract should be investigated further as a viable option in the treatment of colorectal cancer.Цель: исследовать антипролиферативный эффект экстракта Crocus sativus и его главного действующего вещества, кроцина,
на три клеточные линии колоректального рака человека (HCT-116, SW-480 и HT-29). Эффект ингибирования роста
клеток оценивали по отношению к таковому для клеток немелкоклеточного рака легкого (НМРЛ) и немалигнизированных
клеток. Методы: для очистки кроцина и составляющих экстракта C. sativus применяли высокоэффективную жидкостную
хроматографию (ВЭЖХ). Антипролиферативный эффект экстракта и кроцина по отношению к клеткам оценивали при
помощи MTS-теста. Результаты: степень очистки кроцина составляла 95,9%, а содержание кроцина в экстракте –22,9%.
Отмечали существенное дозозависимое угнетение пролиферации клеток трех линий экстрактом C. sativus (P < 0.01). Наиболее
выраженное снижение пролиферативной активности оотмечали для клеток HCT-116 (дo 45,5 % при 1,0 мг/мл и до 6,8 % при
3,0 мг/мл). Кроцин в концентрации 1,0 мM, значительно ингибирует пролиферацию клеток HCT-116, SW-480 и HT-29 (до 2,8,
52 и 16,8% соответственно, P < 0,01). Поскольку 3,0 мг/мл экстракта C. sativus содержат приблизительно 0,6 мM кроцина,
отмеченное действие первого подтверждает тот факт, что кроцин — главное действующее начало экстракта. Также показано
существенное антипролиферативное действие по отношению к клеткам НМРЛ. Однако C. sativus не оказывал выраженного
действия на рост немалигнизированных клеток толстого кишечника молодых мышей. Выводы: данные представленного
исследования показывают, что экстракт Crocus sativus и его главный действующий компонент кроцин значительно ингибируют
рост клеточных линий колоректального рака и в то же время не влияют на рост нормальных клеток. В дальнейшем следует
изучить возможность применения Crocus sativus для лечения больных колоректальным раком
Zero-current-switch Quasi-resonant boost converter in power factor correction applications
A modified zero-current-switched quasi-resonant (ZCS-QR) boost converter is employed in a power factor correction (PFC) application. The main goal is to achieve a small-size low-noise PFC circuit based on single-switch boost topology. A clamp diode has been added to avoid the voltage ringing problem that is originally generated across the ZCS-QR switch during its turn-off period. The converter operation states after clamp diode application are presented. The PFC circuit control scheme implementation is also described. An experimental circuit with 100 V rms ac of 50 Hz input and 330 V dc output has been built. A high efficiency of 90% and the proof of compliance to the IEC61000-3-2 class D have been confirmed by experiment.24th Annual IEEE Applied Power Electronics Conference and Exposition, APEC 2009; Washington, DC; 15 February 2009 through 19 February 200
A critical-conduction-mode bridgeless interleaved boost power factor correction
This paper explains about fundamental working principles, governing equations, implementation problems, and experimental results of a new power factor correction (PFC) topology. In this proposed topology, bridgeless technique is applied to a critical-conduction-mode (CRM) interleaved boost PFC in order to gain fundamental understanding towards high efficiency, high performance, low-cost, simple control scheme, and low conducted electromagnetic interference (EMI) circuit. This application is targeted for low to middle power applications that normally employs continuous or interleaved boost converter.INTELEC 2009 - 2009 International Telecommunications Energy Conference : Incheon, South Korea, 2009.10.18-2009.10.2
Mitochondrial Changes in Ageing Caenorhabditis elegans – What Do We Learn from Superoxide Dismutase Knockouts?
One of the most popular damage accumulation theories of ageing is the mitochondrial free radical theory of ageing (mFRTA). The mFRTA proposes that ageing is due to the accumulation of unrepaired oxidative damage, in particular damage to mitochondrial DNA (mtDNA). Within the mFRTA, the “vicious cycle” theory further proposes that reactive oxygen species (ROS) promote mtDNA mutations, which then lead to a further increase in ROS production. Recently, data have been published on Caenorhabditis elegans mutants deficient in one or both forms of mitochondrial superoxide dismutase (SOD). Surprisingly, even double mutants, lacking both mitochondrial forms of SOD, show no reduction in lifespan. This has been interpreted as evidence against the mFRTA because it is assumed that these mutants suffer from significantly elevated oxidative damage to their mitochondria. Here, using a novel mtDNA damage assay in conjunction with related, well established damage and metabolic markers, we first investigate the age-dependent mitochondrial decline in a cohort of ageing wild-type nematodes, in particular testing the plausibility of the “vicious cycle” theory. We then apply the methods and insights gained from this investigation to a mutant strain for C. elegans that lacks both forms of mitochondrial SOD. While we show a clear age-dependent, linear increase in oxidative damage in WT nematodes, we find no evidence for autocatalytic damage amplification as proposed by the “vicious cycle” theory. Comparing the SOD mutants with wild-type animals, we further show that oxidative damage levels in the mtDNA of SOD mutants are not significantly different from those in wild-type animals, i.e. even the total loss of mitochondrial SOD did not significantly increase oxidative damage to mtDNA. Possible reasons for this unexpected result and some implications for the mFRTA are discussed
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