• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.280-288
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• 2000

In this study, flow factors are evaluated in terms of kurtosis using random rough surface generated numerically. As h/$\sigma$become large øx, øy, øfp approach to 1 and øs, øfs to 0 asymptotically regardless of kurtosis. øx, øy, øfp increase with increasing kurtosis in the mixed lubrication regime. øs, øfs is associated with an additional flow transport due to the combined effect of sliding and roughness. As h/$\sigma$ decreases øs, øfs increase up to a certain point, and then decrease toward zero. This behavior can be attributed to the increasing number of contacts in the mixed lubrication regime. øx in the presence of elastic deformation on the surface is larger than øx in the absence of it because local film thickness( h$\_$T/) increases by elastic deformation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.6
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• pp.48-54
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• 2007

This paper describes the analysis of transient phenomena on the point that a human body suffers an electrical shock. A couple of case studies were discussed by using an ATPDraw simulation tool. Two models for the case studies were constructed on the assumption that the electrical shock event takes place under water to simulate the severest condition ; the first model that the human body contacts with an energized part exposed to water ; the second model that both hands and feet simultaneously contact with the ground under water. After modeling, the transient phenomena for the models were analyzed by comparing the voltages and currents calculated at each part of the human body. As a result steep front kicks in voltage and current were observed as transient phenomena on the point that the human body contacts with the energized part exposed to water in the first model and the magnitudes of the kicks considerably increased. It was considered however, the effect of the kicks due to the commercial power source on the human body could be neglected because the product of the current through the body and the short duration is less than the safety limit. When both hands and feet simultaneously contact with the ground in the second model, the voltage generally decreased all over the body parts, while the current flowing through the chest abruptly increased. The duration of this current was very shot, as well, thus its effect on the electrical shock is considered insignificant. After all, it was confirmed through the simulation results that the electrical shock depends on the magnitude in voltage and the body impedance.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.1
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• pp.59-68
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• 2013

The objective of this study was to analyze occlusal contact pattern of 33 young adult males with normal occlusion during lateral excursion using T-scan III system which can measure the dynamic occlusion. Occlusal contact patterns were examined and categorized in non-working side disclusion point(more functionally acceptable position) not canine-to-canine position. Disclusion time, occlusal force, and occlusal force distribution ratio of upper canine at disclusion point during lateral excursion movement was also measured and compared among the groups divided according to contact patterns. The results showed that group function was clearly more dominant than canine guidance and other occlusal contact patterns different with existing patterns were found. There were significantly difference between groups in variables of T-scan measurement. T-scan III system is effective tools to analyze and evaluate occlusal contact patterns, disclusion time, occlusal force, and occlusal force distribution ratio of upper canine at disclusion point.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.5
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• pp.398-406
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• 2003

In modular fixturing systems, a given part or a subassembly is fixed by placing fixture elements such as locators and clamps adequately on a plate with a lattice of holes. It is known that the minimal number of point contacts to restrict translational and rotational motions on a plane is four and the type of three locators and a clamp(3L/1C) is the minimal future. Brost and Goldberg developed the complete algorithm to automatically synthesize 3L/1C types of fixtures which satisfy the condition of form closure. Due to the nature of the fixture, the clearance between the fixture and the part is extremely small. It is hard to load the part repeatedly and accurately for human as well as for robot. However the condition of loadability has not been taken into account in the B&G algorithm. In this paper, a new method to decide a given fixture to be loadable by using configuration space is proposed. A method to plan for a part to be loaded by using compliance safely even in the presence of control and sensing uncertainty is proposed is well.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.8
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• pp.3568-3584
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• 2016

In mobile opportunistic networks (MONs), human-carried mobile devices such as PDAs and smartphones, with the capability of short range wireless communications, could form various intermittent contacts due to the mobility of humans, and then could use the contact opportunity to communicate with each other. The dynamic changes of the network topology are closely related to the human mobility patterns. In this paper, we propose a social motivation-aware mobility model for MONs, which explains the basic laws of human mobility from the psychological point of view. We analyze and model social motivations of human mobility mainly in terms of expectancy value theory and affiliation motivation. Furthermore, we introduce a new concept of geographic functional cells, which not only incorporates the influence of geographical constraints on human mobility but also simplifies the complicated configuration of simulation areas. Lastly, we validate our model by simulating three real scenarios and comparing it with reality traces and other synthetic traces. The simulation results show that our model has a better match in the performance evaluation when applying social-based forwarding protocols like BUBBULE.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.106-109
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• 2000

The virtual reality - haptic device is developed for the purpose used in the work that human cannot approach and that need elaborate exercises. To render haptic, the total system is constituted master, haptic device, and slave, remote manipulator. Human operates the remote manipulator. Human operates the remote manipulator relying on the hapti devices and stereo graphic. And then the force and scene of the remote manipulator is fed-back from each haptic devices and virtual devices. The feedback information gets system gain exactly. The system gain provides the most exact haptic and virtual devices. The feedback information gets system gain exactly. The system gain provides the most exact haptic and scene to human by the location, the graphic rendering and the haptic rendering algorithm on real-time. In this research, 3D haptic device is developed for common usage and make human feel the haptic when human contacts virtual object rendered by computer graphic. The haptic device is good for tracing location and producing devices because of the row structure. Also, openGL and Visual Basic is utilized to the algorithms for haptic rendering. The haptic device of this research makes the interface possible not only with virtual reality but also with the real remote manipulator.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.288-291
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• 2002

Application of metal silicides such as TiSi$_2$ and CoSi$_2$ as contacts and gate electrodes are being studied. However, TiSi$_2$ due to the linewidth-dependance, and CoSi$_2$ due to the excessive Si consumption during silicidation cannot be applied to the deep-submicron MOSFET device. NiSi shows no such problems and can be formed at the low temperature. But, NiSi shows thermal instability. In this investigation, NiSi was formed with a Ti-capping layer to improve the thermal stability. Ni and Ti films were deposited by the thermal evaporator. The samples were then annealed in the N$_2$ ambient at 300-800$^{\circ}C$ in a RTA (rapid thermal annealing) system. Four point probe, FESEM, and AES were used to study the thermal properties of Ti-capped NiSi layers. The Ti-capped NiSi was stable up to 700$^{\circ}C$ for 100 sec. RTA, while the uncapped NiSi layers showed high sheet resistance after 600$^{\circ}C$. The AES results revealed that the Ni diffusion further into the Si substrate was retarded by the capping layer, resulting in the suppression of agglomeration of NiSi films.

• The Journal of the Korean dental association
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• v.17 no.11 s.126
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• pp.849-853
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• 1979

The number of occlusal contact points and he occlusal relation were investigated in dental students who were selected on the basis of normal occlusion and normal function of stomatognathic system. Silicone-Black Bites obtained from fifty subjects were analyzed on their white models and occlusal contacts were traced on models directly. The results were as follows; 1. There was no evident difference in the number of occlusal contact points between right and left sides 2. In the retruded position the numbers of occlusal contact points were $5.96{\pm}3.35$ in the upper jaws and $6.12{\pm}3.52$ in the lower jaws. 3. In the retruded position no occlusal contact point was found on the central and lateral incisors of upper and lower jaws. 4. Occlusal contact points were found almost on second molars of upper and lower jaws in the retruded position.

• Proceedings of the KSPS conference
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• 1996.10a
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• pp.245-245
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• 1996

When language A borrows words, it borrows them according to its own phonetic rules. In other words, language B, where borrowed words coming from, has to comply with the phonetic requirements of language A. It may be added that language A only borrows the elements, the types of syllables and accentuation that already exist in its own phonetic struture and rejects all the rest that are not compatible. It operates exactly like a sieve. That is why borrowed words offer an excellent observation post to notice how react in phonetic contexts. The Japanese language has borrowed and is borrowing extensively from other languages and cultures, mainly from the English ones in the fields of sports, medicine, industry, commerce, and natural sciences. Relatively very few new words are created using the ancient Chinese or native backgrounds. This presentation will look for the rules of borrowing and try to show that this way of borrowing represents an organized system of its own. Three levels would be particularly studied : - the phonemic level - the syllable level and - the accentual level. This last point would be specially targeted with the question of syllable tension-relaxation. Such a study of languages in phonetics contacts could shed some new light on the phonetic charaCteristics of Japanese language and will confirm or weaken some conclusion already demonstated otherwise. We will be aming specially at the endings of the borrowed words where, it seems, Japanese language manifests itself very strongly.

• Tribology and Lubricants
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• v.17 no.3
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• pp.236-243
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• 2001

In this study, flow factors are evaluated in terms of kurtosis using random rough surface generated numerically. As h/$\sigma$become large ø$\sub$x/, ø$\sub$y/, ø$\sub$fp/, approach to 1 and ø$\sub$s/, ø$\sub$fs/ to 0 asymptotically regardless of kurtosis. ø$\sub$x/, ø$\sub$y/, ø$\sub$fp/ increase with increasing kurtosis in the mixed lubrication regime. ø$\sub$s/, ø$\sub$fs/ is associated with an additional flow transport due to the combined effect of sliding and roughness. As h/$\sigma$ decreases ø$\sub$s/, ø$\sub$fs/ increase up to a certain point, and then decrease toward zero. This behavior can be attributed to the increasing number of contacts in the mixed lubrication regime. ø$\sub$x/ in the presence of elastic deformation on the surface is larger than ø$\sub$x/ in the absence of it because local film thickness(h$\sub$T/) increases by elastic deformation.