• The Journal of Korean Physical Therapy
• /
• 제5권1호
• /
• pp.61-69
• /
• 1993

It was performed to encourage for Physical Therapist to apply the theory of center of the human body and segments in clinical situations. This study was investigated literarily on center of the human body and segments. Methods which search for the center-2 types, that is, method using reaction broad and segmental method-was suggested. The center location difference of gravity in human body depends on individual character. Generally, the center location is in kent of 2nd sacrum, that is, at $55\%$ of height from foot. The center of each segment is on 'link'. In the first place we must how the weight of segment we can search for the center easily. Mean segment coater location of extremities is at $42.33\%$ from each proximal end, and mean center of head and trunk lies at $45\%$.

• 한국소음진동공학회논문집
• /
• 제20권11호
• /
• pp.1052-1057
• /
• 2010

Dynamic stability of rotating blade considering gravity effect is investigated in this paper. Equations of motion for the beam is derived by employing hybrid deformation variable method and transformed into dimensionless form. The present modeling method is verified by RecurDyn. Stability diagrams are presented to show the influence of the configuration of the beam and angular velocity on the dynamic stability by applying Floquet's theory. Since the natural frequencies are varied when the blade has rotating motion, it is found that relatively large unstable regions exist approximately 1.1 times as high as the first bending natural frequency and half of the sum of first and second bending natural frequency.

• International Journal of Control, Automation, and Systems
• /
• 제4권5호
• /
• pp.545-558
• /
• 2006

In this paper, PD-like visual servoing is modified in two ways: a sliding-mode observer is applied to estimate the joint velocities, and a RBF neural network is used to compensate the unknown gravity and friction. Based on Lyapunov method and input--to-state stability theory, we prove that PD-like visual servoing with the sliding mode observer and the neuro compensator is robust stable when the gain of the PD controller is bigger than the upper bounds of the uncertainties. Several simulations are presented to support the theory results.

• 한국지반공학회지:지반
• /
• 제12권6호
• /
• pp.101-114
• /
• 1996

Coulomb토압이론은 실무에서 주로 사용되고 있음에도 불구하고 점성토로 뒤채움된 옹벽에 대한 일반적인 조건에 적용할 수 있는 토압이론식이 존재하지 않는다. 여기서는 점성토로 뒤채움한 중력식 옹벽에 대해서 배수 및 비배수 해석으로 인장균열이 부시된 경우와 고려된 경우에 각각 토압이론식을 유도하였다. 그리고 상기의 조건들에 대해서 전주동토압과 인장균열 깊이를 구하여 설계도표를 작성하였다.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권12호
• /
• pp.657-664
• /
• 2020

We investigate the impact of roads and highways within the provinces on the regional trade of China using the augmented Gravity Model and theory of modeling trade. We take a panel data covering 31 provinces of China over 20 years period (1998-2017) for the estimations. We apply ARMA-OLS model, fixed and random effects, and robust findings by Hausman test. The results imply that road and highway lengths within the provinces have a significantly positive impact on the value of the province-wise exports. The positive impact is due to the fact the increased coverage of roads and highways increase accessibility to resources and mobility of goods and services within the regions. Moreover, employment in the transportation sector, per capita GDP and population of the provinces also illustrate positive and significant influence on regional exports and trade. The impact of China's WTO accession on regional exports has been positive, while the financial crisis has had a negative impact. The year dummies show that, in the years following the financial crisis, China was able to regress from the external shock as trade within the provinces increased. The increase in exports after financial crisis is mainly due to the government policies and support to every province.

• 천문학회보
• /
• 제42권2호
• /
• pp.37.1-37.1
• /
• 2017

Since the seminal work of Perrin, physicists have understood in the context of kinetic theory how ink slowly diffuses in a glass of water. The fluctuations of the stochastic forces acting on water molecules drive the diffusion of the ink in the fluid. This is the archetype of a process described by the so-called fluctuation-dissipation theorem, which universally relates the rate of diffusion to the power spectrum of the fluctuating forces. For stars in galaxies, a similar process occurs but with two significant differences, due to the long-range nature of the gravitational interaction: (i) for the diffusion to be effective, stars need to resonate, i.e. present commensurable frequencies, otherwise they only follow the orbit imposed by their mean field; (ii) the amplitudes of the induced fluctuating forces are significantly boosted by collective effects, i.e. by the fact that, because of self-gravity, each star generates a wake in its neighbours. In the expanding universe, an overdense perturbation passing a critical threshold will collapse onto itself and, through violent relaxation and mergers, rapidly converge towards a stationary, phase-mixed and highly symmetric state, with a partially frozen orbital structure. The object is then locked in a quasi-stationary state imposed by its mean gravitational field. Of particular interests are strongly responsive colder systems which, given time and kicks, find the opportunity to significantly reshuffle their orbital structure towards more likely configurations. This presentation aims to explain this long-term reshuffling called gravity-driven secular evolution on cosmic timescales, described by extended kinetic theory. I will illustrate this with radial migration, disc thickening and the stellar cluster in the galactic centre.

• 한국감성과학회:학술대회논문집
• /
• 한국감성과학회 2008년도 추계학술대회
• /
• pp.46-49
• /
• 2008

This study aims to suggest basic materials to develop an emotional font for future Hangeul font development plan by investigating emotional reaction displayed through the subjects and by quantifying its contribution of the stimulation elements causing such reaction. For this, a survey of 150 university students who are currently enrolled in the College of Design was conducted in order to analyze correlation between 30 emotional words extracted from the Hangeul font and the selected 36 sample fonts. The combined data was described with the two dimensional dispersion using the quantification theory type III. The analysis found out that the Hangeul font forms the x-axis showing "soft(dynamic).hard(static)" and the y-axis showing "modern(light).classic(heavy)”. Specifically, there exist emotional groups such as "archaic","masculine","feminine","negative", and "modern static"on each axis. In addition, to extract the casual relationship between the value of emotional reaction and its stimulation elements quantitatively, the author indicated the emotional words of each axis and the total value of equivalent five emotional word groups as the standard variance and the constituent of Hangeul font as the independent variable, and then the quantification theory type I was used to analyze the physical elements of the Hangeul font. As a result, "the centerline of gravity(base line)" and "thickness variance of a stroke" on the two axes, and "the centerline of gravity(base line)" and "decoration" among the five groups were identified as the most influential elements that affect the emotional reaction of the subjects.

• 문화기술의 융합
• /
• 제8권6호
• /
• pp.531-536
• /
• 2022

전 세계적으로 국가경쟁력, 효용성, 중요성 등의 이유로 메가시티가 속속 등장하고 있으며, 점차 각 국가의 중심지로 자리를 잡아가고 있다. 또한, 메가시티는 현존, 잠재적, 초국가, 비군사 등 다양한 위협에 노출될 수밖에 없다. 특히, 최근 우크라이나-러시아 전쟁에서 볼 수 있듯이 국가기반체계는 적대 및 위협세력의 주요 목표가 되고 있다. 하지만 메가시티의 막대한 규모, 다양한 위협의 양상, 한정된 자원 등을 고려할 때 모든 국가기반체계를 완벽하게 방호하는 것은 현실적으로 어렵다. 따라서 여러 국가기반체계 중 핵심노드를 식별하여 중점적으로 방호하는 접근이 필요하다. 핵심노드는 다양한 국가기반시설이 연결된 국가기반체계의 중요도가 매우 높면서도 동시에 급소에 해당한다. 이를 위해 본 연구에서는 핵심노드를 논리적·체계적으로 식별하기 위해 네트워크 이론인 노드 중심성(Centrality) 분석방법과 군사이론인 중심(Center of Gravity) 분석방법을 제시하였다.

• 한국지반환경공학회 논문집
• /
• 제12권3호
• /
• pp.63-67
• /
• 2011

실무에서 불포화토의 적용이 증가하고 있다. 불포화토의 가장 큰 특징은 체적함수비와 모관흡수력의 관계를 나타내는 함수특성곡선이다. 일반적으로 체적함수비는 측정의 어려움으로 인하여 중량함수비를 측정한 후 관계식을 통하여 체적함수비를 구한다. 이 경우 흙의 간극과 비중을 이용하여 관계식이 성립되는데 사실 물은 흙 입자 자체에도 포함되어 있다. 그러므로 실제 체적함수비는 중량함수비를 관계식으로 변화한 값과 다르게 된다. 본 연구에서는 실험을 통하여 얻어진 흙 입자의 흡수율을 고려하여 체적함수비와 중량함수비의 관계를 제시하는 데 있다.

• 한국환경복원기술학회지
• /
• 제7권1호
• /
• pp.97-109
• /
• 2004

The disposal of stormwater is one of the major problems in urban water management. One method of reducing peak runoff rates and other detrimental impacts of stormwater is detention storage. Detention ponds as a water quality control alternatives have been investigated by a number of researchers. Recognizing multiple roles such as flood peak attenuation, pollution removal and aesthetic enhancement, the design and management of detentions ponds deserve more research. The purpose of this research is to establish design criteria wet detention ponds to improve water quality. Water quality in detention pond discharge might be improve with physical, chemical and biological alterations. Physical alteration was focused in this study. There are several methods for estimating the suspended solid control capability of wet detention ponds. Existing models of suspended solids removal are based on sedimentation and gravity settling theory. The pollutant trap efficiency of pond is a function of several interrelating factors. Detention time is the most important factor, because it determine gravity settling quantities of pollutants. Desirable modification of physical factors for improvement of water quality in wet detention ponds are volume ratio, area ratio, length to width ratio, depth, out let location, bottom soil type. In order to apply design procedure in actual site, Namak new town development area was selected.