• Journal of Communications and Networks
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• 제7권3호
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• pp.325-336
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• 2005

Mobile ad hoc networks (MANET) are composed of moving wireless hosts which, within range of each other, form wireless networks. For communication to occur between hosts that are not within each other's range, routes involving intermediate nodes must be established; however, since the hosts may be in motion, a host that was part of a route may move away from its upstream and downstream partners, thus breaking the route. In this paper, we propose anticipated route maintenance (ARM) protocol with two extensions to route discovery based routing scheme: Extend the route when nodes on a link move apart from each other and they have common neighbor that can be 'inserted' in the path, and shrink route when a node discovers that one of its neighbor which is not the next hop is also on the same route several hops later on. By utilizing only local geographic information (now a part of some route finding algorithms), a host can anticipate its neighbor's departure and, if other hosts are available, choose a host to bridge the gap, keeping the path connected. We present a distributed algorithm that anticipates route failure and performs preventative route maintenance using location information to increase a route lifespan. The benefits are that this reduces the need to find new routes (which is very expensive) and prevents interruptions in service. As the density of nodes increases, the chance to successfully utilize our route maintenance approach increases, and so does the savings. We have compared the performance of two protocols, pure dynamic source routing (DSR) protocol and DSR with ARM. The simulation results show how ARM improves the functionality of DSR by preventing the links in the route from breaking. Packets delivery ratio could be increased using ARM and achieved approximately $\100%$ improvement. The simulations clarify also how ARM shows a noticeable improvement in dropped packets and links stability over DSR, even though there is more traffic and channel overhead in ARM.

• 한국운동역학회지
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• 제16권1호
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• pp.151-158
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• 2006

The purpose of this study was to find out the kinematical characteristics of arm's basic position in ballet. In order to achieve the purpose of the study, 3D cinematographic analysis was conducted with a ballerina who might performed the perfect arm's basic position. According to the results of this study, it was appeared that the shoulder kept about 78%-82%, the elbow kept about 62%-96%, the wrist kept 52%-109%, and finger kept 48%-110% with the height. Also, movement was formed with $21^{\circ}-77^{\circ}$ of the upper arm angle, $106^{\circ}-164^{\circ}$ of the elbow, $125^{\circ}-140^{\circ}$ of the wrist, and $83^{\circ}-160^{\circ}$ of the shoulder. The left-right ratio of the total arm angle was 98% in the first, second, and third position, and 100% in the forth position. The angle of arm gradient was remained $-68^{\circ}$ in the first position, $-27^{\circ}$ in the second position, $73^{\circ}$ in the third position, and $-11^{\circ}$ in the forth position. Based on the results mentioned above, balance and symmetry of both arms was an important factor in those four positions. Although it is impossible to maintain the position like robot, it may be a good performance if a certain level of extent was remained With respect to this point of view, it may be a good position if the difference between right and left arm in each joint can be remained within 2%. Angle also was an important factor that if the difference in total angle can be remained within 2% it may be an excellent position, there was difference of right and left based on the joint though. Therefore, practice and instruction to make a perfect symmetry as much as possible were needed Also, it would be a good movement if position and angle of joint within 2% difference of right and left arm can be remained In turn, because ballet is movement with expression of the body, beauty of the body and balance of the movement have to be harmonized for beautiful performance. Therefore, it would be a meaningful future study considering the body condition and movement of ballerina to define the beauty.

• 한국주조공학회지
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• 제28권6호
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• pp.256-260
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• 2008

The Hybrid-Lower Arm, which has been developed for reducing cost and weight, was produced by three kinds of casting methods such as the high-pressure diecasting(HPDC), the squeeze casting(SC), and the H-NCM rheocasting process. The important factors for development of the Hybrid-Lower Arm are the integral feeding in Al casting for heat treatment and the high joinning ratio between the steel part and the Al part. In this study, effects of these casting processes on the quality of Hybrid-Lower Arm were investigated. Compared with HPDC and squeeze casting, the rheocasitng process using the H-NCM slurry had some advantages in joinning different materials of Al and steel pipe without deforming the steel pipe. X-ray analysis also showed the poreless microstructure in semisolid Hybrid-Lower Arm. In the torsion stress test, semisolid Hybrid-Lower Arm was satisfied with the requirements of automobile standard.

• 한국주조공학회지
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• 제3권1호
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• pp.3-12
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• 1983

The influence of columnar dendirtes on the mechanical properties of Al-1% Cu alloys as unifirectionalloy solidified under the conditions of controlled crystal growth rate (R) and temperature gradient (G) was investigated. And the change of metallography and mechanical properties when unifirectionalloy solidified alloys and cast alloys were cold-rolled from 10% to 90% in reduction ratio was studied. The results are as follows: 1. The elongation and yield strength of unifirectionalloy solidified alloy are higher then those of cast alloy, but there is a little decrease in ultimate tensile strength. 2. The metallography and mechanical properties are changeable with the primary arm spacings when the unidirectionalloy solidified alloys were cold-rolled from 10% to 90% in reduction ratio. An alloy with larger primary arm spacings was easily changeable in metallography and mechanical properties when it was cold-rolled. 3. The tensile strength of transversely cold-rolled to 90% in reduction ratio was higher then that of longitudionalloy cold-rolled to 90% in reduction ratio. In the case, the fractorgraphs of fractured surface showed that the cast alloy and the unifirectionalloy solidified alloy was ductile-fractured, but the surface of transversely cold-rolled to 90% reduction of unidirection alloy solidified was slip plane qracture.

• 대한전기학회논문지
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• 제43권6호
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• pp.1027-1035
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• 1994

This paper aims to make an artificial arm control strategy. For this, we propose a new feature extraction method and design artificial neural network for the functional classification of myoelectric signal(MES). We first transform the two channel myoelectric signals (MES) for biceps and triceps into frequency domain using fast Fourier transform (FFT). And features were obtained by comparing the magnitudes of ensemble spectrum data and used as inputs to the three-layer neural network for the learning. By changing the number of units in hidden layer of neural network we observed the improvement of classification performance. To observe the effeciency of the proposed scheme we performed experiments for classification of six arm functions to the three subjects. And we obtained on average 94[%] the ratio of classification.

• 한국기계가공학회지
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• 제7권1호
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• pp.17-21
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• 2008

Recently developed automotive components are of lightweight nature, providing automobiles with a high fuel efficiency and performance. In response to those trends of car developments, this study proposes a structural optimization method for the lower control ann. Lightweight design of lower control am can be achieved through two approaches: design and material technology. In this research, the former includes optimization technology, and the latter the technologies for selecting aluminum as a steel-substitute material. In this research, the design of experiments(DOE) built in ANSYS WORKBENCH are utilized to determine the optimum shape of a Lower Control Arm. And optimum design is compared first model and reduced design variable model that considered sensitivity using orthogonal array.

• 국제물리치료학회지
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• 제2권1호
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• pp.229-236
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• 2011

The purpose of this study was to comparatively analyze the active stability of shoulder joints according to the frequency of overhead motions, such as serving and spiking, engaged in by female professional volleyball athletes who play different positions, and to provide the results as the basic data for developing exercise programs to prevent shoulder joint injuries. The subjects of this study were 50 Korean female professional volleyball players and positions were as follows: left and right attackers, centers, setters, and liberos. The external rotation and internal rotation muscle strength and muscle strength ratios of the dominant and non-dominant arms of all subjects were measured using Biodex. The results of this study are as follows: Frist, no significant differences were found in the internal and external rotation muscle strength of the dominant and non-dominant arms between positions. Second, for the shoulder joint muscle strength ratio of the dominant arm, by position, the setter showed significantly greater stability compared to the other positions. Third, for the shoulder joint muscle strength ratio of the non-dominant arm, by position, no significant difference in stability between positions was found. Fourth, it was found that the dominant arm had significantly greater instability of the shoulder joint than the non-dominant arm for attackers and centers, but no significant difference was found for setters and liberos. This study comparatively analyzed the muscle strength ratios of the external/internal rotations and dominant/non-dominant arms, which can determine the stability of the shoulder joints between female professional volleyball playing positions that engage in jumps and spikes using only the dominant hand and positions that do not.

• Clinics in Shoulder and Elbow
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• 제1권2호
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• pp.221-229
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• 1998

평균 나이 23세.의 건강한 남자 31명을 대상으로 하여 측각도계즐 이용한 견관절운동역을 측정한 결과 Dominant arm과 Non-dominant arm 모두에서 능동운동역에 비해 수동운동역이 증가되었고, 능동운동시 견갑외전, 중립신전, 수평신전, 수평굴곡, 그리고 중립 및 수평내회전에서, 수동운동의 격우에는 견갑외전, 수평굴곡, 그리고 중립 및 수평내회전에서 Non-dominant arm의 운동증가를 보였고, 수평외회전의 경우 Dominant arm의 운동증가소견을 보였다(p〈0.05) .또한 방사선투시기를 이용하여 관절와상완각과 견갑흉곽각의 비(θGH/θST)를 측정해 본 결과 첫째로 Dominant arm과 Non-dominant arm에서 모두 완전거상시 관절와상완각과 견값흥곽각의 비(θGH/θST)는 1.6이었으며 60도이상 150도 거상때까지 지속적으로 견값흉곽운동 분율이 커지는 양상이었다. 둘째천 30도에서 완전거상시까지 운동분율(θGH/θST)은 Dominant arm과 Non-domlnant arm에서 각각 1.2 및 1.3으로 나타났다. 견갑사위는 중립위에서 약 42도였고 거상에 따라 점차 작아졌으며 완전거상시에는 약 20도로 측정되었다. 이렇게 해서 얻어진 방사선조사 각도는 단순방사선 촬영에 적용하여, 견관절 질환 치료 후 운동범위의 회복의 경과를 판정하는데 도움을 줄 수 있을 것으로 생각되었다.

• 동의생리병리학회지
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• 제19권4호
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• pp.1099-1103
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• 2005

This study aims to confirm the importance of behavior habit and exercise, especially leg exercise in obese. Out of 889 people, We divided Group A 50 (BMI<18.5), Group B 210 $(18.5{\leq}BMl<23)$, Group C 202 $(23{\leq}BMI<25)$, Group D212 $(25{\leq}BMI<30)$ and Group 1215 (30

• 복식문화연구
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• 제25권6호
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• pp.847-861
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• 2017

As the excavated costumes from the unknown tomb of the Joseon Dynasty were unearthed, estimating the age of the costumes became very important. This research investigat and estimates the age of the excavated costumes from Couple's Tomb for Lee General in Seosan, Chung-nam. By inspecting and analyzing the costumes, the features can be compared with other similar costumes that have been excavated from other tombs. The result of this study is as follows: First, the period with dopo, cheol-rik, jungchimak, and baji for females among the relics of General Lee can be estimated. For dopo, there are morphometric features such as the shape of moo; for cheol-rik, there is a ratio of top and bottom; for jungchimak, there is a ratio of width of arm and skit and a ratio of side tim, total length, etc. By comparing relics of same period, it can be estimated to be from the late 16 century around the Japanese invasion of Korea to the early 17 century. Second, the period with jangui and jeogori among the relics of Couple's Tomb for General Lee can be estimated. By comparing jangui with the arm and width of sleeves, and by comparing jeogori and the shape of the collar, arm, length, etc., with other relics identical to the period, it can be estimated to be from the late 16 century around the Japanese invasion of Korea, which is a similar date to the one with the husband to the early 17 century.