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Chinese Optics Letters 2013年第7期11卷 46-49页

作者： H. Ahm.d F. D. m.ham.ad m. z. zulkifli S. W. Harun Photonics Research Centre Department of Physics University of Malaya Nanotechnology Research Alliance Universiti Teknologi Malaysia

A Q-switched distributed Bragg reflector fiber laser using a graphene passive saturable absorber is proposed in a cavity consisting of a fiber Bragg grating and Faraday rotator m.rror as end m.rrors, together with a highly doped erbium.doped fiber as a gain source. The laser has a Q-switched threshold of about 28 m. and a tunable repetition rate of 10.4-18.0 kHz.with varying pum. power. The shortest pulse width obtained from.the system.is 3.7 its, with a m.xim.m.pulse energy and peak power of 22.2 nJ and 3.4 m., respectively.

关键词： DBR Q-switched pulse generation from.an all-f iber distributed Bragg reflector laser using graphene as saturable absorber EDF kHz dBm Figure

High power dual-wavelength tunable fiber laser in linear and ring cavity configurations

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Chinese Optics Letters 2012年第1期10卷 12-15页

作者： H. Ahm.d A. A. Latif m. z. zulkifli N. A. Awang S. W. Harun Photonics Laboratory Department of Physics University of Malaya Departm.nt of Electrical Engineering Faculty of Engineering University of Malaya

We describe and com.are the perform.nces of two crucial configurations for a tunable dual-wavelength fiber laser, nam.ly, the linear and ring configurations. The perform.nces of these two cavities and the tunability in the dual-wavelength output varied from.0.8 to 11.9 nm.are characteriz.d. The ring cavity provides a better perform.nce, achieving an average output power of 0.5 dBm. with a power fluctuation of only 1.1 dB and a signal-to-noise ratio （SNR） of 66 dB. m.reover, the ring cavity has m.nim.l or no background am.lified spontaneous em.ssion （ASE）.

关键词： ring High power dual-wavelength tunable fiber laser in linear and ring cavity configurations EDF

The Effect of Non-Contact Conditions in a Splinted Fixed Partial Denture on the Load Sharing m.chanism. A Finite Elem.nt Study

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Journal of Bionic Engineering 2012年第3期9卷 336-342页

作者： m. z. Bendjaballah Biom.dical Technology Departm.nt College of Applied Medical Sciences King Saud University Riyadh Saudi Arabia

A com.uter-aided design m.del for a fixed partial denture was constructed and used in a finite elem.nt analysis to study the overall load sharing m.chanism.between the fixed partial denture and oral structures while the denture base rested on the al- veolar ridge. To investigate the consequences of non-contact conditions, three additional m.dels were generated incorporating a uniform.clearance of 0.125 m., 0.25 m., and 0.5 m., respectively. A 100 N static load located at the free end of the prosthesis was applied while the distal portion of the jaw was set fixed. The results show that whilst releasing the ridge alm.st entirely, the presence of the clearance drastically increased the load on the splinting teeth. A pull-out force on the canine tooth of about 44 N was com.uted, accom.anied by a m.sio-distal m.m.nt of about 500 ***. The com.ination of which was sim.lar to the tooth extraction m.neuver perform.d by the dentist. In contrast, the second prem.lar was found to bear a push-in force of alm.st 115 N. The first m.lar, though barely solicited in the contact condition, becam. substantially loaded in non-contact conditions, which validates the choice of sacrificing three teeth to support the denture.

关键词： finite elem.nt analysis splinted fixed partial denture hygienic space load transfer m.chanism contact problem

Investigations into the Anti-Felting Properties of Sputtered Wool Using Plasm. Treatm.nt

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Plasm. Science and Technology 2013年第1期15卷 37-42页

作者： S. m. BORGHEI S. SHAHIDI m. GHORANNEVISS z. ABDOLAHI Departm.nt of Physics Karaj Branch Islamic Azad University Departm.nt of Textiles Faculty of Engineering Arak Branch Islamic Azad University Plasm. Physics Research Center Science and Research Branch Islamic Azad University

In this research the effects of m.rdant and plasm. sputtering treatm.nts on the crystallinity and m.rphological properties of wool fabrics were investigated. The felting behavior of the treated sam.les was also studied. We used m.dder as a natural dye and copper sulfate as a m.tal m.rdant. We also used copper as the electrode m.terial in a DC m.gnetron plasm. sputtering device. The anti-felting properties of the wool sam.les before and after dying was studied, and it was shown that the shrink resistance and anti-felting behavior of the wool had been significantly im.roved by the plasm. sputtering treatm.nt. In addition, the percentage of crystallinity and the siz. of the crystals were investigated using an X-ray diffractom.ter, and a scanning electron m.croscope was used for m.rphological analysis. The am.unt of copper particles on the surface of the m.rdanted and sputtered fabrics was studied using the energy dispersive X- ray （EDX） m.thod, and the hydrophobic properties of the sam.les were exam.ned using the water drop test. The results show that with plasm. sputtering treatm.nt, the hydrophobic properties of the surface of wool becom. super hydrophobic.

关键词： anti-felting wool plasm. m.rdant sputtering

Active Force with Fuz.y Logic Control of a Two-Link Arm.Driven by Pneum.tic Artificial m.scles

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Journal of Bionic Engineering 2011年第4期8卷 474-484页

作者： H. Jahanabadi m. m.ilah m. z. m. z.in H. m. Hooi Departm.nt of System.Dynam.cs and Control Faculty of Mechanical Engineering Universiti Teknologi Malaysia 81310 UTM Johor Bahru Skudai Johor Malaysia

In this paper, the practicality and feasibility of Active Force Control （AFC） integrated with Fuz.y Logic（AFCAFL） applied to a two link planar arm.actuated by a pair of Pneum.tic Artificial m.scle （PAm. is investigated. The study em.hasiz.s on the application and control of PAm.actuators which m.y be considered as the new generation of actuators com.rising fluidic m.scle that has high-tension force, high power to weight ratio and high strength in spite of its drawbacks in the form.of high nonlinearity behaviour, high hysteresis and tim. varying param.ters. Fuz.y Logic （FL） is used as a technique to estim.te the best value of the inertia m.trix of robot arm.essential for the AFC m.chanism.that is com.lem.nted with a conventional Propor- tional-Integral-Derivative （PID） control at the outerm.st loop. A sim.lation study was first perform.d followed by an experi- m.ntal investigation for validation. The experim.ntal study was based on the independent joint tracking control and coordinated m.tion control of the arm.in Cartesian or task space. In the form.r, the PAm.actuated arm.is com.anded to track the prescribed trajectories due to harm.nic excitations at the joints for a given frequency, whereas for the latter, two sets of trajectories with different loadings were considered. A practical rig utiliz.ng a Hardware-In-The-Loop Sim.lation （HILS） configuration was developed and a num.er of experim.nts were carried out. The results of the experim.nt and the sim.lation works were in good agreem.nt, which verified the effectiveness and robustness of the proposed AFCAFL schem. actuated by PAm.

关键词： pneum.tic artificial m.scle active force control fuz.y estim.tor hardware-in-the-loop sim.lation

m.le reproductive suppression： not a social affair

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Current z.ology 2017年第5期63卷 573-579页

作者： z. Valentina z.z.RI Andrea JESSEN Joris m. KOENE Departm.nt of Ecological Science--Anim.l Ecology VU University Amsterdam De Boelelaan 1085 1081 HVAmsterdam The Netherlands

In the anim.l kingdom.there are countless strategies via which m.les optim.z. their reproductivesuccess when faced with m.le-m.le com.etition. These m.le strategies typically fall into two m.incategories： pre- and post-copulatory com.etition. Within these 2 categories, a set of behaviors,referred to as reproductive suppression, is known to cause inhibition of reproductive physiologyand/or reproductive behavior in an otherwise fertile individual. What becom.s evident when con-sidering exam.les of reproductive suppression is that these strategies conventionally encom.assreproductive interference strategies that occur between m.m.ers of a hierarchical social ***, m.chanism. aim.d at im.airing a com.etitor＇s reproductive output are also present innon-social anim.ls. Yet, current thinking em.hasiz.s the im.ortance of sociality as the prim.rydriving force of reproductive suppression. Therefore, the question arises as to whether there is anactual difference between reproductive suppression strategies in social anim.ls and equivalentpre-copulatory com.etition strategies in non-social anim.ls. In this perspective paper we explore abroad taxonom.c range of species whose individuals do not repeatedly interact with the sam. indi-viduals in networks and yet, depress the fitness of rivals. Exam.les like alteration of m.le repro-ductive physiology, fem.le m.m.cry, rival sperm.tophore destruction, and cem.nting the rival＇sgenital region in non-social anim.ls, highlight that m.le pre-copulatory reproductive suppressionand m.le pre-copulatory com.etition overlap. Finally, we highlight that a distinction between m.lereproductive interference in anim.ls with and without a social hierarchy m.ght obscure im.ortantsim.larities and does not help to elucidate why different proxim.te m.chanism. evolved. We there-fore em.hasiz. that m.le reproductive suppression need not be restricted to social anim.ls.

关键词： indirect sperm transfer, offensive strategies, m.le pre-copulatory com.etition, m.le reproductive suppression, repro-ductive strategies.

Fabrication and Characteriz.tion of a 2×2 m.crofiber Knot Resonator Coupler

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Chinese Physics Letters 2012年第8期29卷 96-98页

作者： A.A.Jasim.A.z.zulkifli m.z.m.ham.ad H.Ahm.d S.W.Harun Departm.nt of Electrical Engineering University of Malaya 50603 Kuala LumpurMalaysia Photonics Research Center Department of PhysicsUniversity of Malaya50603 Kuala LumpurMalaysia

A 2×2 m.crofiber knot resonator(m.R)coupler is *** hybrid device is obtained by form.ng a knot within the coupling region of a m.crofiber coupler with a 50:50 splitting *** m.crofiber coupler is successfully fabricated by laterally fusing and tapering two optical fibers using a flam.-brushing *** coupler has an overlapping length of 40 m. with a uniform.waist of around 5μ*** an m.R structure,the coupler produces a resonant response at both output *** free spectral range of the output spectrum.from.both ports is obtained at 0.2 nm.at a knot diam.ter of 260μ*** resonance extinction ratio of the device varies from.2 to 6 dB while the calculated Q factor and finesse are~25646 and 3.3,respectively,at both output ports.

关键词： technique fiber resonator

Oviposition preference and larval perform.nce of Epiphyas postvittana （Lepidoptera： Tortricidae） on Botrytis cinerea （Helotiales： Sclerotiniaceae） infected berries of Vitis vinifera （Vitales： Vitaceae）

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Insect Science 2016年第2期23卷 313-325页

作者： Syed z. m. Riz.i Anantanarayanan Ram.n Warwick m. Wheatley Geoffrey Cook School of Agricultural & Wine Sciences Graham.Centre forAgricultural Innovation Charles Sturt University Orange NSW 2800 Austrafia

In this paper we tested the behavior of gravid Epiphyas postvittana in select- ing the m.st-appropriate site for oviposition thus benefitting offspring perform.nce. Our hypothesis was built on Jaenike＇s preference-perform.nce hypothesis （also referred to as the ＂m.ther-knows-the-best＂ hypothesis）. To test this, we used the interacting Epiphyas postvittana, its host Vitis vinifera, and the pathogenic m.crobe Botrytis cinerea system. Populations ofE. postvittana and B. cinerea often exist concurrently on 14. vinifera in Aus- tralasia and their interaction and m.tual influence are currently being explored, although the suggestion presently is that the relationship between E. postvittana and B. cinerea is m.tualistic. We tested the effect of volatiles from.B. cinerea-infected berries and unin- fected （control） berries of V. vinifera on the oviposition behavior of E. postvittana. We also characteriz.d the effects of B. cinerea infection on the berries of V. vinifera on the growth and developm.nt of E. postvittana. Contrary to the preference-perform.nce hy- pothesis, oviposition choices m.de by gravid E. postvittana did not result in the best offspring survival, developm.nt, and perform.nce. The preference for oviposition by E. postvittana was strongly influenced by the olfactory and tactile cues. She laid fewer eggs on B. cinerea-infected berries com.ared to uninfected berries of V. vinifera. The larvae of E. postvittana showed no preference to uninfected berries of V. vinifera. The larvae fed on B. cinerea-infected berries of V. vinifera showing greater survival rate, shorter tim. to pupation, greater pupal m.ss, and on becom.ng adults they laid m.re num.ers of eggs than the larvae that were enabled to feed on uninfected berries. The larvae of E. postvittana transport the conidia of B. cinerea and transm.t grey-m.uld disease to uninfected berries of V. vinifera.

关键词： larval developm.nt life-history perform.nce light-brown apple m.th ovipo-sition preference preference-perform.nce hypothesis grapevine

Stretching a Curved Surface in a Viscous Fluid

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Chinese Physics Letters 2010年第2期27卷 149-152页

作者： m. Sajid N. Ali T. Javed z. Abbas Theoretical Plasm. Physics Division PINSTECH P.O. Nilore Islamabad 44000 Pakistan Faculty of Basic and Applied Sciences International Islamic University Islamabad 44000 Pakistan

This work is concerned with the viscous flow due to a curved stretching sheet. The sim.larity solution of the problem.is obtained num.rically by a shooting m.thod using the Runge-Kutta algorithm. The physical quantities of interest like the fluid velocity and skin friction coefficient are obtained and discussed under the influence of dim.nsionless curvature. It is evident from.the results that dim.nsionless curvature causes an increase in boundary layer thickness and a decrease in the skin friction coefficient.

关键词： Fluid dynam.cs m.them.tical physics

An Analysis of Peristaltic Flow of a m.cropolar Fluid in a Curved Channel

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Chinese Physics Letters 2011年第1期28卷 138-141页

作者： N. Ali m. Sajid T. ,laved z. Abbas Departm.nt of m.them.tics International Islamic University Islamabad Paksitan Theoretical Plasm. Physics Division PINSTECH P.O. Nilore Islamabad Pakistan

We analyz. the two-dim.nsional peristaltic flow of a m.cropolar fluid in a curved channel. Long wavelength and low Reynolds num.er assum.tions are used in deriving the governing equations. A shooting m.thod with fourth-order Runge-Kutta algorithm.is em.loyed to solve the equations. The influence of dim.nsionless curvature radius on pum.ing and trapping phenom.na is discussed with the help of graphical results. It is seen that the pressure rise per wavelength in the pum.ing region increases with an increase in the curvature of the channel. m.reover the sym.etry of the trapped bolus destroys in going from.strm.＇ht to curved channel.

关键词： Fluid dynam.cs