Journal of Bionic Engineering

Drag Reduction in a Swimming Humboldt Penguin, Spheniscus Humboldti, when the Boundary Layer is Turbulent

Alex R.Parfitt, Julian F.V. Vincent

J4. 2005, 2 (2): 57-62. DOI:

Abstract ( 1421 )

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An area of protruding feathers found around the beak of many penguin species is thought to induce a turbulent boun~dary layer whilst swimming. Hydrodynamic tests on a model Humboldt penguin, Spheniscus humboldti, suggest that induced turbulence causes a significant reduction in boundary layer height, flow separation, and an average of 31 % reduction in drag (1.0 m/s to 4.5 m/s). Visualisation of surface flow showed it to follow the body profile, over the feet and tail, before separating. Movement of the feet in swimming penguins correlates with steering of the bird. Induced turbulence may therefore further increase swimming efficiency by reducing the amount of foot movement required to direct the swimming bird.

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Investigation of Micro-wear and Micro-friction Properties for Bionic Non-smooth Concave Components

Han Zhi-wu¹, Xu Xiao-xia², Qiu Zhao-mei¹, Ren Lu-quan¹

J4. 2005, 2 (2): 63-67. DOI:

Abstract ( 1421 )

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Five kinds of 45# steel samples with concave features on the surface were manufactured using Laser Texturing Technology (LTT). Optimum design theory was used to design the experiment, and a two-level orthogonal table - L₁₆(2¹⁵) design was adopted . Micro-wear and micro-friction experienced by samples with concave surface features and samples with smooth surfaces were compared experimentally. The wear resistance of samples with concave surface features was increased most, and different surface morphologies had different effects on friction and wear properties.

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Properties and Application of Ironbased Shape Memory Alloy

Li Jian-chen¹, Jiang Qing¹, Dai Jun²

J4. 2005, 2 (2): 69-73. DOI:

Abstract ( 1302 )

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The properties of FeMnSiCrNi shape memory alloy were investigated. The results show that the best shape memory effect of Fe14Mn6Si9Cr5Ni alloy is 85%. The transformation amount of the ε→γ transformation is not complete after heating the alloy to 1000 K, A_s and A_fpoints drop with increased transformation enthalpy (ΔH^γ→ε) by thermal cycling and increased prestrain. The alloy shows also good creep and stress relaxation resistance. In addition, the alloy having a tensile force of 20 kN and a sealing pressure of 6 MPa can satisfy requirements for possible industrial application on pipe joints.

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Spectral Test Instrument for Color Vision Measurement

Balázs Vince Nagy, György <SPAN lang=EN-GB style=

J4. 2005, 2 (2): 75-79. DOI:

Abstract ( 1474 )

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Common displays such as CRT or LCD screens have limited capabilities in displaying most color spectra correctly. The main disadvantage of these devices is that they work with three primaries and the colors displayed are the mixture of these three colours. Consequently these devices can be confusing in testing human color identification, because the spectral distribution of the colors displayed is the combined spectrum of the three primaries. We have developed a new instrument for spectrally correct color vision measurement. This instrument uses light emitting diodes (LEDs) and is capable of producing all spectra of perceivable colors, thus with appropriate test methods this instrument can be a reliable and useful tool in test~ing human color vision and in verifying color vision correction.

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Wear Resistance of 3Cr2W8V Rough Surfaces

Zhou Hong¹, Wang Wei¹, Ren Lu-quan², Li Yue³, Li Chen¹

J4. 2005, 2 (2): 81-86. DOI:

Abstract ( 1441 )

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Three types of rough surface were processed by laser irradiation on the 3Cr2W8V material hot-work die steel surface. The wear experiments with smooth surface and rough surface samples were repeated on the pin-tray wear machine. According to the wear results, we studied the regularity of wear resistance of different rough surface samples. The results indicated that bionic rough surface can improve the wear resistance of the material and the wear resistance can be increased 1-2 times, compared with the smooth surface. Also, the wear resistance of the rough surface was affected by laser current and duration of impulse. The bigger the laser current or the impulse duration, the better is the wear resistance. When the distance between the same kind of units which are distributed on the surfaces is changed, the wear resistance changes. The wear resistance of a bionic rough surface on which the grid units were distributed at spacing of 1 mm was the best. And we designed the wear models.

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Improved Cardiac Contractility of Human Recombinant Growth Hormone on the Congestive Heart Failure of Pig

Yang Ping¹, He Yu-quan¹, Zeng Hong¹, Ni Jin-song², Yun Qing-jun¹, Huang Xiao-ping¹, Li Shu-mei³

J4. 2005, 2 (2): 87-91. DOI:

Abstract ( 1576 )

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The enhanced cardiac contractility effect of human recombinant growth hormone (hr-GH) on the congestive heart failure (CHF) was studied on the pig. To build a pig model of congestive heart failure, a temporary artificial cardiac pacemaker was implanted in the pig's body and paced at 220 beats to 240 beats per minute for 1 week. After the model of congestive heart failure was successfully set up, the frequency of the pacemaker was changed to 150 beats to 180 beats per minute to maintain the CHF model stable. Pigs were divided into three groups: The hr-GH group in which 0.5 mg/kg per day of hr-GH was administrated intramuscularly for 15 days, the injection control group in which an equal amount of physiological saline was injected intramuscularly, and a normal control group. The left ventricular diastolic end pressure was (10.60±2.41) mmHg in the hr-GH group, but (19.00±3.81) mmHg in the saline control group (P<0.01); Cardiac output was (1.86±0.13) L/min in the hr-GH group, but (1.56±0.18) L/min in the saline control group (P<0.05); Peripheral vascular resistance was (56.88±7.51) mmHg·(L/min)^-1 in the hr-GH group, whereas (70.30±11.59) mmHg·(L/min)^-1 in the saline control group (P<0.05); +dp/dt_maxwas (2900±316.23) and (2280±286.36) in the hr-HG group and the saline control group respectively (P<0.05). The results show that hr-GH enhances myocardial contractility of CHF, and the CHF model built by a temporary artificial cardiac pacemaker at a high rate of stimulation is reasonable and applicable.

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The Nature of Materials

Julian F. V. Vincent

J4. 2005, 2 (2): 93-114. DOI:

Abstract ( 1175 )

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This first essay is about a pending marriage between biology and some of the technologies of engineering. It is a story of a longstanding flirtation that has been consummated a number of times, but never properly solemnised, despite repeated attempts, and no one is quite sure how many of the offspring, if any, have been viable. Whether the union will be blessed in the near future is anyone’s guess. In the hope of helping the marriage on its way, I start with four lucky things the bride has to wear at the wedding for the marriage to succeed, at least in one of the more recent Western traditions.

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