• Journal of the Korean Society for Precision Engineering
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• v.18 no.6
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• pp.174-181
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• 2001

An upper bound elemental technique(UBET) has been carried out to predict the forming load, the deformation pattern and the extrude length of the lateral extrusion of a spider for the automotive universal joint. For the upper bound analysis, a kinematically admissible velocity field(KAVF) is proposed. From the proposed velocity field, the upper bound load, the deformation pattern and the average length of the extruded billets are determined by minimizing the total energy consumption rate which is a function of unknown velocities at each element. Experiments are carried out with antimony-lead billets at room temperature using the rectangular shape punch. The theoretical prediction of the forming load, the deformation pattern and the extruded length are good in agreement with the experimental results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1101-1104
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• 2004

A brake spider in an irregular shape, which is used as a part in the braking system of a vehicle like a big truck and a trailer, is subjected to a large torque and hence requires both strength and endurance over the brake heat. Manufacture of this product in practice is generally composed of hot forging processes and machining. At the present study, two or more processes were considered for the hot forging. With an initial circular billet, blocker and finisher processes were analyzed using the rigid-plastic finite element method and also in addition to the preforming process. Proper forging processes to manufacture an irregular product without forging defects, which are preforming, blocker and finisher, were discussed and commented upon.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1097-1100
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• 2004

A rear axle spider in an irregular shape, which is used as a part in the braking system of a vehicle like a big truck and a trailer, is subjected to a large torque and hence requires both strength and endurance over the brake heat. This part should be therefore manufactured in dimensional accuracy. The practical manufacturing process of this irregular product requires the heat treatment process after hot forging and then the cold coining process for the dimensional accuracy. At the present study, the warm coning without the heat treatment process was proposed to employ the residual heat due to the hot forging process. And also the trimming and piercing process was designed using the rigid-plastic finite element method. The mechanical properties were discussed and also commented upon.

• Journal of Astronomy and Space Sciences
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• v.31 no.2
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• pp.101-120
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• 2014

The nature of the exotic stellar corpses which reincarnate by consuming their companion is reviewed. Apart from sucking life from their partners, they are actually eating the doomed companions away by their deadly and powerful particle/radiation beams. Such situation resembles that a female "black widow" spider that eats its mate after mating. These celestial zombies are called - Millisecond pulsars (MSPs). In this review article, I will focus on the effort of Fermi Asian Network (FAN) in exploring these intricating objects over the last five years. Two special classes of MSPs are particularly striking. Since Fermi Gamma-ray Space Telescope has started surveying the gamma-ray sky, the population of "black widows" has been boosted. Another dramatic class is so-called "redbacks" (Australian cousin of "black widows") which has just emerged in the last few years. These MSPs provide us with a long-sought missing link in understanding the transition between accretion-powered and rotation-powered systems. The strategy of hunting MSPs through mulitwavelength observations of the unidentified Fermi objects is also reviewed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1129-1133
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• 2001

An upper bound elemental technique(UBET) has been carried out to predict the forming load, the deformation pattern and the extruded length of the lateral extrusion of a spider for the automotive universal joint. For the upper bound analysis, a kinematically admissible velocity field(KAVF) is proposed. From the proposed velocity field, the upper bound load, the deformation pattern and the average length of the extruded billets are determined by minimizing the total energy consumption rate which is a function of unknown velocities at each element. Experiments are carried out with antimony-lead billets at room temperature using the rectangular shaped punch. The theoretical prediction of the forming load, the deformation pattern and the extruded length are good in agreement with the experimental results.

• Animal cells and systems
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• v.13 no.2
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• pp.153-160
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• 2009

The fine structural characteristics of the silk spinning apparatus in the titanoecid spiders Nurscia albofasciata have been examined by the field emission scanning electron microscopy (FESEM). This titanoecid spiders have a pair of medially divided cribella just in front of the anterior spinnerets, and the surface of the cribellum is covered by hundred of tiny spigots which produce numerous cribellate silk fibrils. The cribellar silks are produced from the spigots of the sieve-like prate. and considered as a quite different sort of catching silk with dry-adhesive properties. The other types of the silk spigots were identified as follows: ampullate, pyriform and aciniform glands. Two pairs of major ampullate glands send secretory ductules to the anterior spinnerets, and another 1-2 pairs of minor ampullate glands supply the middle spinnerets. In addition, the pyriform glands send ductules to the anterior spinnerets, and two kinds of the aciniform spigots feed silk into the middle (A type) and the posterior spinnerets (both of A & B types), respectively.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.163-168
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• 2002

We report for the first time the cDNA sequence encoding a ferritin subunit from the spiders Araneus ventricosus. The complete cDNA sequence of A. ventricosus ferritin subunit comprised 516 bp with 172 amino acid residues. The A. ventricosus ferritin subunit cDNA contained a conserved iron responsive element sequence in the 5 untranslated region. An alignment of the deduced protein sequence of the A. ventricosus ferritin subunit gene to that of other heavy chain ferritin molecules showed that A. ventricosus ferritin subunit is most similar to the great pond snail, Lymnaea stagnalis, ferritin with 70.2% of protein sequence identity.

• IEIE Transactions on Smart Processing and Computing
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• v.3 no.6
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• pp.393-396
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• 2014

Recently, the internet of things (IoT) has become increasingly attractive in many areas to realize smart worlds. JavaScript has become prevalent for IoT programming because of its familiarity with web programmers. On the other hand, JavaScript does not allow the direct control of IoT hardware due to its language limitation. This paper proposes the IoT software platform for JavaScript programming to resolve the limitation. For proof of concept, the platform based on SpiderMonkey and Raspberry Pi was implemented.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.2
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• pp.69-73
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• 1998

With increased loads in steered wheels and wider section tires the effort required at the steering wheel makes the driver's job very tiring and difficult. Improvements such as an increase in the mechanical efficiency of the steering system or lower steering box ratios help the reduce driver fatigue. Now using of power steering is increasing. It needs to be considering parts size of steering system as using power steering. This paper presents adjust part size of steering system form estimating reliability according to reducing torque under the dynamic load, In this paper, the spider of universial joint is selected to prove relation between steering and power steering reliability.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1427-1432
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• 2008

This paper describes the locomotion of a water jumping robot which attempts to emulate the fishing spider’s ability to jump on the water surface. While previous studies of the robots mimicking arthropods living on water were focused on recreating their horizontal skating motions, here we aim to achieve a vertical jumping motion. The robot jumps by pushing the water surface with rapidly released legs which were initially bent. The motion is triggered with a latch driven by the shape memory alloy actuator. The robot is capable of jumping to the maximum height of 26mm. Jumping efficiency, defined the maximum jumping height on water over the maximum jumping height on rigid ground, is 0.26 This work represents a first step toward robots that can locomote on water with superior versatility including skating and jumping.