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On the Minimization of Crosstalk Conflicts in a Destination Based Modified Omega Network

  • Bhardwaj, Ved Prakash;Nitin, Nitin
    • Journal of Information Processing Systems
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    • v.9 no.2
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    • pp.301-314
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    • 2013
  • In a parallel processing system, Multi-stage Interconnection Networks (MINs) play a vital role in making the network reliable and cost effective. The MIN is an important piece of architecture for a multiprocessor system, and it has a good impact in the field of communication. Optical Multi-stage Interconnection Networks (OMINs) are the advanced version of MINs. The main problem with OMINs is crosstalk. This paper, presents the (1) Destination Based Modified Omega Network (DBMON) and the (2) Destination Based Scheduling Algorithm (DBSA). DBSA does the scheduling for a source and their corresponding destination address for messages transmission and these scheduled addresses are passed through DBMON. Furthermore, the performance of DBMON is compared with the Crosstalk-Free Modified Omega Network (CFMON). CFMON also minimizes the crosstalk in a minimum number of passes. Results show that DBMON is better than CFMON in terms of the average number of passes and execution time. DBSA can transmit all the messages in only two passes from any source to any destination, through DBMON and without crosstalk. This network is the modified form of the original omega network. Crosstalk minimization is the main objective of the proposed algorithm and proposed network.

Glucose Oxidation on Gold-modified Copper Electrode

  • Lim, Ji-Eun;Ahn, Sang Hyun;Pyo, Sung Gyu;Son, Hyungbin;Jang, Jong Hyun;Kim, Soo-Kil
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2685-2690
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    • 2013
  • The activities of Au-modified Cu electrodes toward glucose oxidation are evaluated according to their fabrication conditions and physico-chemical properties. The Au-modified Cu electrodes are fabricated by the galvanic displacement of Au on a Cu substrate and the characteristics of the Au particles are controlled by adjusting the displacement time. From the glucose oxidation tests, it is found that the Au modified Cu has superior activity to the pure Au or Cu film, which is evidenced by the negative shift in the oxidation potential and enhanced current density during the electrochemical oxidation. Though the activity of the Au nanoparticles is a contributing factor, the enhanced activity of the Au-modified Cu electrode is due to the increased oxidation number of Cu through the electron transfer from Cu to more electronegative Au. The depletion of electron in Cu facilitates the oxidation of glucose. The stability of the Au-modified Cu electrode was also studied by chronoamperometry.

Analysis of PVDF Coating Properties with Addition of Hydrophobically Modified Fumed Silica

  • Lee, Nam Kyu;Kim, Young Hoon;Im, Tae Gyu;Lee, Dong Uk;Shon, MinYoung;Moon, Myung Jun
    • Corrosion Science and Technology
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    • v.18 no.6
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    • pp.232-242
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    • 2019
  • In this study, hydrophobically modified fumed silica was added to the PVDF coating to improve corrosion protection performance. Two types of silane modifiers, trimethylchlorosilane (TMCS) and hexamethyldisilazane (HMDZ), were used for hydrophobic modification of the fumed silica. The composition of modified fumed silica was analyzed by Fourier transform infrared, X-ray photoelectron spectroscopy, and elemental analysis. The dispersion of modified fumed silica in the PVDF coating was observed by the transmission electron microscopy, and the hydrophobicity of PVDF coating was analyzed by the water contact angle. Surface properties were examined by the field emission scanning electron microscopy and scanning probe microscopy. Potentiodynamic polarization was conducted to confirm corrosion protection performance of PVDF coating in terms of hydrophobically-modified fumed silica contents. As a result, the average surface roughness and the water contact angle of the PVDF coating increased with modifier contents. The results of the potentiodynamic polarization test showed an increase of the Ecorr values with increase of the hydrophobicity of PVDF coating. Thus, it clearly indicates that the corrosion protection performance of PVDF coating improved with the addition of the hydrophobic-modified fumed silica that prevents the penetration of moisture into the PVDF coating.

Effects of surface modification with hydroxyl terminated polydimethylsiloxane on the corrosion protection of polyurethane coating

  • Jeon, Jae Hong;Shon, MinYoung
    • Corrosion Science and Technology
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    • v.13 no.5
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    • pp.170-177
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    • 2014
  • Polyurethane coating was designed to give a hydrophobic property on its surface by modifying it with hydroxyl terminated polydimethylsiloxane and then effects of surface hydrophobic tendency, water transport behavior and hence corrosion protectiveness of the modified polyurethane coating were examined using FT-IR/ATR spectroscopy, contact angle measurement and electrochemical impedance test. As results, the surface of polyurethane coating was changed from hydrophilic to hydrophobic property due primarily to a phase separation tendency between polyurethane and modifier by the modification. The phase separation tendency is more appreciable when modified by polydimethylsiloxane with higher content. Water transport behavior of the modified polyurethane coating decreased more in that with higher hydrophobic surface property. The decrease in the impedance modulus ${\mid}Z{\mid}$ at low frequency region in immersion test for polyurethane coatings was associated with the water transport behavior and surface hydrophobic properties of modified polyurethane coatings. The corrosion protectiveness of the modified polyurethane coated carbon steel generally increased with an increase in the modifier content, confirming that corrosion protectiveness of the modified polyurethane coating is well agreed with its water transport behavior.

Anti-aging Effects Saccharomyces Fermented Modified Kyungohkgo Extract on Skin (경옥고(瓊玉膏) 가미방(加味方) 효모(酵母) 발효물(醱酵物)이 피부(皮膚) 노화(老化)에 미치는 영향(影響))

  • Choi, Jae-Hwan;Kim, Hyoung-Man;Song, Young-Sook;Park, Sun-Gyoo;Kim, Jin-Jun;Lee, Cheon-Koo
    • The Korea Journal of Herbology
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    • v.22 no.4
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    • pp.219-225
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    • 2007
  • Objectives : We investigated the anti-aging effects on skin with Saccharomyces fermented modified Kyungohkgo extract (SFKE). Methods : Fermented modified Kyungohkgo extracts by 14 different kinds of microorganism were prepared and most effective Saccharomyces fermented modified Kyungohkgo extract among these was selected for anti-aging agent. We measured various effects related to skin such as scavenging activity against free radical, cell proliferation, collagen synthesis and toxicity of SFKE were evaluated and compared with modified Kyungohkgo extract (KE). Results : Free-radical scavenging activity and cell proliferating ratio of SFKE were 2 and 8 times higher than those of KE. The SFKE could significantly increase the collagen synthetic ratio compared with KE treated group. SFKE showed no toxicity at all tested concentrations. Conclusions : The results of our study propose that SFKE have good anti-aging effects on skin.

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Modified Current Differential Relay for Transformer Protection Unaffected by Remanent flux (잔류자속에 무관한 변압기 보호용 수정전류차동 계전기)

  • 강용철;김은숙
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.53 no.9
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    • pp.500-506
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    • 2004
  • This paper proposes a modified current differential relay for transformer protection unaffected by the remanent flux. The relay uses the same restraining current as a conventional relay, but the differential current is modified to compensate for the effects of the exciting current. To cope with the remanent flux, before saturation, the relay calculates the core-loss current and uses it to modify the measured differential current. When the core then enters saturation, the initial value of the flux is obtained by inserting the modified differential current at the start of saturation into the magnetization cure. Thereafter, the actual core flux is then derived and used in conjunction with the magnetization curve to calculate the magnetizing current. A modified differential current is then derived that compensates for the core-loss and magnetizing currents. The performance of the proposed differential relay was compared against a conventional differential relay. Results indicate that the modified relay remained stable during severe magnetic inrush and over-excitation because the exciting current was successfully compensated. This paper concludes by implementing the relay on a hardware platform based on a digital signal processor. The relay discriminates magnetic inrush and over-excitation from an internal fault and is not affected by the level of remanent flux.

Comparison of Effects Between Modified Vertical Roll Sling and Bobath Roll Sling in Hemiplegic Shoulder Subluxation

  • Kim, Dong-Hyun;Kim, Tack-Hoon;Roh, Jung-Suk;Cynn, Heon-Seock;Choi, Houng-Sik;Oh, Dong-Sik
    • Physical Therapy Korea
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    • v.15 no.4
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    • pp.64-69
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    • 2008
  • The purpose of this study was to compare the effectiveness of modified vertical roll sling and conventional Bobath roll sling in reducing hemiplegic shoulder subluxation. Radiography of $40^{\circ}$ anterior oblique radiographic view' were taken, before and immediately after wearing each sling in 13 hemiplegic patients. The vertical distance. horizontal distance. and joint distance were measured. Analysis of radiographically measured distances showed that both modified vertical roll sling and Bobath roll sling decreased vertical, horizontal. and joint distances. Reduction in vertical and joint distances were significantly greater in modified vertical roll sling compared to Bobath roll sling. while horizontal distance showed no significant difference between the two slings. Therefore it can be concluded that modified vertical roll sling is an effective orthosis in reducing hemiplegic shoulder subluxation.

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Modified Finite Volume Time Domain Method for Efficient Prediction of Radar Cross Section at High Frequencies

  • Chatterjee, Avijit;Myong, Rho-Shin
    • Journal of electromagnetic engineering and science
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    • v.8 no.3
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    • pp.100-109
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    • 2008
  • The finite volume time domain(FVTD) technique faces serious limitations in simulating electromagnetic scattering at high frequencies due to requirements related to discretization. A modified FVTD method is proposed for electrically large, perfectly conducting scatterers by partially incorporating a time-domain physical optics(PO) approximation for the surface current. Dominant specular returns in the modified FVTD method are modeled using a PO approximation of the surface current allowing for a much coarser discretization at high electrical sizes compared to the original FVTD scheme. This coarse discretization can be based on the minimum surface resolution required for a satisfactory numerical evaluation of the PO integral for the scattered far-field. Non-uniform discretization and spatial accuracy can also be used in the context of the modified FVTD method. The modified FVTD method is aimed at simulating electromagnetic scattering from geometries containing long smooth illuminated sections with respect to the incident wave. The computational efficiency of the modified FVTD method for higher electrical sizes are shown by solving two-dimensional test cases involving electromagnetic scattering from a circular cylinder and a symmetric airfoil.

Hardening Properties of Hardener-Free Epoxy-Modified Mortars by Curing Conditions (양생조건에 따른 경화제 무첨가 에폭시수지 혼입 PMM의 경화특성)

  • Lee, Jae-Hwa;Kim, Joo-Young;Kim, Wan-Ki
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.11a
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    • pp.255-257
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    • 2012
  • Epoxy resin without any hardener can harden in the presence of hydroxide ions in cement mortars and concretes at ambient temperature. The purpose of present study is to examine the hardening properties of hardener-free epoxy-modified mortars by curing conditions. The hardener-free epoxy-modified mortars using diglycidyl ether of A epoxy resin are prepared with various polymer-cement ratios, and subjected to initial moist/dry curing, initial steam(90℃) curing, initial steam/heat(80℃, 100℃) curing.As a result, degree of hardening of epoxy resin in initial moist/dry cured, initial steam cured and initial steam/heat(80℃) cured hardener-free epoxy-modified mortars is decreased with increasing polymer-cement ratio. However, it is markedly improved with additional dry-curing periods. On the other hand, regardless of the polymer-cement ratio and dry curing periods, degree of hardening of hardener-free epoxy-modified mortars with initial steam/heat(100℃) cure is over 95%.

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Treatment for Distal Humeral Fractures by Modified Anatomical Y-Plate (변형된 Y형 해부학적 금속판을 이용한 상완골 원위부 골절의 치료)

  • Moon Eun Sun;Park Jae Hyung;Lee Young Keun
    • Clinics in Shoulder and Elbow
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    • v.1 no.1
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    • pp.51-57
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    • 1998
  • Comminuted fracture of the distal end of the humerus in adults is very rare and difficult to treat. In operative treatment, an implant which can achieve accurate anatoraical reduction and rigid fixation is needed. But the pre­existing Y -shaped plate had wide and thick limbs and some problems in fixation for most distal humeral fractures. So we devised a modified plate which is more narrow and th1n and has a different hole distance and wing length (long lateral wing). The aim of the study was to evaluate the clinical result of this modified anatomical Y -plate. From 1991 to 1997, we treated 23 cases of distal humeral fractures using modified anatomical plate and the results were as follows. 1. Fracture type in 18 patients(78%) was C-type(C1,C2,C3) which were intraarticular and mostly displaced or comminuted. 2. Bony union was obtained in 22 patients(96%) through rigid fixation and observed radiologically at 3.5 months(2-6months) on the average. 3. In 23 patients, 19 patients(82%) showed satisfactory results after 34 months(6-73months) follow-up. So if the modified anatomical Y-plate is used in the treatment of distal humeral fracture, a satisfactory result can be obtained through a more accurate, easy, and rigid fixation than preexisting plate.

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