• Title/Summary/Keyword: PIC18

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Design and Implementation of Firmware for Low-cost Small PCR Devices (저가의 소형 PCR 장치를 위한 펌웨어 설계 및 구현)

  • Lee, Wan Yeon;Kim, Jong Dae
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.6
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    • pp.1-8
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    • 2013
  • In this paper, we design and implement a firmware for low-cost small PCR devices. To minimize machine code size, the proposed firmware controls real-time tasks simultaneously only with support of the hardware interrupt, but without support of the operating system program. The proposed firmware has the host-local structure in which the firmware receives operation commands from PC and sends operation results to PC through usb communication. We implement a low-cost small PCR device with the proposed firmware loaded on microchip PIC18F4550 chip, and verify that the implemented PCR device significantly reduces cost and volume size of existing commercial PCR devices with a similar performance.

Implementation of Multi-function Sensor Module for Vessel Safety Monitoring (어선안전 모니터링 다기능 센서 모듈의 구현)

  • Choi, Jo-Cheon;Cho, Seung-Il;Kim, Seong-Kweon;Kim, Jai-Hyun;Choi, Gyoo-Seok;Cha, Jea-Sang
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.6
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    • pp.135-139
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    • 2009
  • In order to cope with safety issues regarding fisher vessels, a device is required with the real-time monitoring for the safety and risk factors for a capability of informing and alerting function. In embedded modules, there is a trouble that we should design device drivers and application programs for usage of the multi-function sensors in order to detect risk factors. In this paper, we designed hardware circuit and implemented control program of the sensor part using PIC18F, in order to control and process the input and output data of multi-function sensors without device drivers and application programs. We confirmed the operation of multi-function sensor module to generate output data according to sensor operation.

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Effect of Oroxylin A on Hydrogen Peroxide Production in Polyinosinic-Polycytidylic acid-induced TM4 Mouse Testis Sertoli Cells (Oroxylin A가 polyinosinic-polycytidylic acid로 유발된 생쥐 서톨리세포 TM4의 hydrogen peroxide 생성증가에 미치는 영향)

  • Park, Wan Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.28 no.4
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    • pp.384-389
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    • 2014
  • The purpose of this study is to investigate the modulatory effect of oroxylin A on hydrogen peroxide production in TM4 mouse testis sertoli cells induced by the synthetic analog of double-stranded RNA [polyinosinic-polycytidylic acid]. Hydrogen peroxide production was measured by dihydrorhodamine 123 (DHR) assay. Oroxylin A significantly inhibited the polyinosinic-polycytidylic acid (PIC)-induced production of hydrogen peroxide for 0.5, 2, 12, 18, and 24 hr incubation at the concentrations of 5, 10, 25, and $50{\mu}M$ in TM4 (P < 0.05) in dose dependent manner. These results suggest that oroxylin A has a protective effect against PIC-induced cellular toxicity with its inhibition of hydrogen peroxide production in PIC-induced sertoli cells.

Analysis of Microsatellite DNA Polymorphisms for Pedigree Verification in Kyungju Dog(Dongkyung-i). (경주개(동경이)의 혈통확인을 위한 microsatellite DNA 다형성 분석)

  • Lee, Eun-Woo;Choi, Seog-Gyu;Cho, Gil-Jae
    • Journal of Life Science
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    • v.18 no.6
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    • pp.902-906
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    • 2008
  • In this study, we analyzed the microsatellite DNA poly-morphisms for pedigree verification in Kyungju dog (Dongkyung-i) which is one of the Korean breed dogs. A total of 51 Dongkyung-i samples were genotyped using 8 microsatellite markers. The number of alleles observed at single locus ranged from 4 to 12, with average number of alleles per locus of 8.5. The expected heterozygosity and polymorphic information contents (PIC) values of the 8 microsatellite loci were $0.6162{\sim}0.8746$ (mean 0.7587) and $0.5461{\sim}0.8512$ (mean 0.7167), respectively. Of the 8 markers, PEZ3, PEZ6, PEZ12 and FHC2054 loci had relatively high PIC values (>0.7) in Dongkyung-i. Pedigree verification of Dongkyung-i was analyzed based on alleles observed. The results of the parentage testing were noted significant differences compared with breeders. These results show basic information of conservation and research in Dongkyung-i, and further studies of genetic pedigree in Dongkyung-i will be needed.

Microcontroller based Chaotic Lorenz System for Secure Communication Applications (암호통신 응용을 위한 마이크로 컨트롤러 기반 로렌츠 카오스 시스템)

  • Jayawickrama, Chamindra;Song, Hanjung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.12
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    • pp.1698-1704
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    • 2018
  • This paper presents a implementation of a chaotic Lorenz system for data secure communication applications. Here we have used PIC18F family-based microcontroller to generate the chaotic signal, and simulated waveform patterns confirm that the chaotic behavior of the microcontroller based discrete time chaotic Lorenz system. There are three R-2R ladder type A/D converters have been implemented for conversion of direct microcontroller digital output into analog waveform, utilizing this specific microcontroller relevant to this experiment work, microcontroller ports B, C and D have been utilized for its time waveform outputs X, Y and Z respectively. XC8 compiler used for the compilation of the program. MATLAB and PROTEUS software platforms are used for simulation. Finally, chaotic time wave forms, 2D chaotic attractors were obtained and secure communication analog waveforms were also verified by experimental measurement.

Synthesis, Structure, and Reactivity of the [Fe4S4(SR)4]2- (R = 2-, 3-, and 4-Pyridinemethane) Clusters

  • Kim, Yu-Jin;Han, Jae-Hong
    • Bulletin of the Korean Chemical Society
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    • v.33 no.1
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    • pp.48-54
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    • 2012
  • The $[Fe_4S_4]^{2+}$ clusters with 2-, 3-, and 4-pyridinemethanethiolate (S2-Pic, S3-Pic, and S4-Pic, respectively) terminal ligands have been synthesized from the ligand substitution reaction of the $(^nBu_4N)_2[Fe_4S_4Cl_4]$ (I) cluster. The new $(^nBu_4N)_2[Fe_4S_4(SR)_4]$ (R = 2-Pic; II, 3-Pic; III, 4-Pic; IV) clusters were characterized by FTIR and UV-Vis spectroscopy. Cluster II was crystallized in the monoclinic space group C2/c with a = 24.530 (5) $\AA$, b = 24.636(4) $\AA$, c = 21.762(4) $\AA$, ${\beta}=103.253(3)^{\circ}$, and Z = 8. The X-ray structure of II showed two unique 2:2 site-differentiated $[Fe_4S_4]^{2+}$ clusters due to the bidentate-mode coordination by 2-pyridinemethanethiolate ligands. Cluster III was crystallized in the same monoclinic space group C2/c with a = 26.0740(18) $\AA$, b = 23.3195(16) $\AA$, c = 22.3720(15) $\AA$, ${\beta}=100.467(2)^{\circ}$, and Z = 8. The 3-pyridinemethanethiolate ligand of III was coordinated to the $[Fe_4S_4]^{2+}$ core as a terminal mode. Cluster IV with 4-pyridinemethanethiolate ligands was found to have a similar structure to the cluster III. Fully reversible $[Fe_4S_4]^{2+}/[Fe_4S_4]^+$ redox waves were observed from all three clusters by cyclic voltammetry measurement. The electrochemical potentials for the $[Fe_4S_4]^{2+}/[Fe_4S_4]^+$ transition decreased in the order of II, III and IV, and the reduction potential changes by the ligands were explained based on the structural differences among the complexes. The complex III was reacted with sulfonium salt of $[PhMeSCH_2-p-C_6H_4CN](BF_4)$ in MeCN to test possible radical-involving reaction as a functional model of the [$Fe_4S_4$]-SAM (S-adenosylmethionine) cofactor. However, the isolated reaction products of 3-pyridinemethanethiolate-p-cyanobenzylsulfide and thioanisole suggested that the reaction followed an ionic mechanism and the products formed from the terminal ligand attack to the sulfonium.

Effect of Emodin on Hydrogen Peroxide Production in Polyinosinic-Polycytidylic acid-induced Human Neuroblastoma SH-SY5Y Cells (Emodin이 polyinosinic-polycytidylic acid로 유발된 인간 신경모세포종 SH-SY5Y의 hydrogen peroxide 생성증가에 미치는 영향)

  • Lee, Ji-Young;Kim, Young-Jin;Park, Wan-Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.25 no.6
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    • pp.1039-1043
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    • 2011
  • The purpose of this study is to investigate the modulatory effect of emodin on hydrogen peroxide production in human blastoma SH-SY5Y cells induced by the synthetic analog of double-stranded RNA [polyinosinic-polycytidylic acid]. Hydrogen peroxide production was measured by dihydrorhodamine 123 (DHR) assay. Emodin significantly inhibited the polyinosinic-polycytidylic acid (PIC)-induced production of hydrogen peroxide for 0.5, 2, 12, 18, and 24 hr incubation at the concentrations of 5, 10, 25, and 50 uM in SH-SY5Y (P < 0.05) in dose dependent manner. These results suggest that emodin has neuroprotective property related with its inhibition of hydrogen peroxide production in PIC-induced neuronal cells.

Effect of Wogonin on Hydrogen Peroxide Production in Polyinosinic-Polycytidylic acid-induced Human Neuroblastoma SH-SY5Y Cells (Wogonin이 polyinosinic-polycytidylic acid로 유발된 인간 신경모세포종 SH-SY5Y의 hydrogen peroxide 생성증가에 미치는 영향)

  • Park, Wan-Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.4
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    • pp.491-496
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    • 2012
  • The purpose of this study is to investigate the modulatory effect of wogonin on hydrogen peroxide production in human blastoma SH-SY5Y cells induced by the synthetic analog of double-stranded RNA [polyinosinic-polycytidylic acid]. Hydrogen peroxide production was measured by dihydrorhodamine 123 (DHR) assay. Wogonin significantly inhibited the polyinosinic-polycytidylic acid (PIC)-induced production of hydrogen peroxide for 0.5, 2, 12, 18, and 24 hr incubation at the concentrations of 10, 25, and 50 ${\mu}M$ in SH-SY5Y (P < 0.05) in dose dependent manner. These results suggest that wogonin has neuroprotective property related with its inhibition of hydrogen peroxide production in PIC-induced neuronal cells.

Optimum Hybrid SVPWM Technique for Three-level Inverter on the Basis of Minimum RMS Flux Ripple

  • Nair, Meenu D.;Biswas, Jayanta;Vivek, G.;Barai, Mukti
    • Journal of Power Electronics
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    • v.19 no.2
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    • pp.413-430
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    • 2019
  • This paper presents an optimum hybrid SVPWM technique for three-level voltage source inverters (VSIs). The proposed hybrid SVPWM technique aims to minimize total harmonic distortion (THD). A new parameter is introduced to incorporate the heterogeneous nature of switching sequences of SVPWM technique. The proposed hybrid SVPWM technique is implemented on a low-cost PIC microcontroller (PIC18F452) and verified experimentally with a 2 KVA three-phase three-level insulated gate bipolar transistor-based VSI. Optimum switching sequence results in the three-level inverter configuration are demonstrated. The proposed hybrid SVPWM technique improves the THD performance by 17.3% compared with the best available three-level SVPWM technique.

Microcontroller based Chaotic Lorenz System for secure communication applications (암호통신 응용을 위한 마이크로 컨트로러 기반 로렌츠 카오스 시스템)

  • Jayawickrama, Chamindra;Kang, Bogyeong;Al-Shidaifat, AlaaDdin;Park, Yongsu;Song, Hanjung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2018.10a
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    • pp.487-489
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    • 2018
  • This paper presents chaotic Lorenz system implementation for secure data communication applications. In this work chaotic signal is generated by a PIC18F family based microcontroller, XC8 compilers have been utilized for the compilation of C code of microcontroller program. For simulation work Matlab and Proteus platforms were utilized and finally, chaotic time waveforms, 2D and 3D chaotic attractor were obtained and secure communication waveforms were achieved successfully.

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