• 한국전문물리치료학회지
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• 제9권1호
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• pp.53-61
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• 2002

The purpose of this study was to compare the body alignment during standing on level and wedge board. Twenty healthy college students (8 females, 12 males) were evaluated in this study. Diagnostic contourline potographic imaging system (Model JTC-1, Jodang Trading Co.) was used to measure body alignment. Sagittal and frontal plane images were used to analyze the body alignment. The result showed that the cervical and lumbar lordotic curve significantly decreased during standing on wedge board when compared with standing on level. On the other hand, thoracic kyphosis significantly increased during standing on wedge board. There was no significant difference in body alignment according to gender, weight, and height. Clinically, patients with low back pain and severe lordosis may be affected by heel wedge. Further study is needed to identify whether the standing on wedge board can change the body alignment in patients with low back pain and spinal deformity.

• 대한기계학회논문집A
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• 제20권1호
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• pp.180-188
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• 1996

The stress singularity of a sharp wedge contacting a half plane can be avoided by changing the wedge shape. Shape optimization is accomplished with the geometric strain method (GSM), an optimality criterion method. Several numerical examples are provided for different materials in the wedge and half plane to avoid stress singularity neal the sharp corner of the wedge. Optimum wedge shapes are obtained and critical corner angles are compared with the angles from analytical contact mechanics. Numerical results are well matched to analytical and experimental results. It is shown that shape optimization by the geometric strain method is a useful tool to reshape the wedge and to avoid a stress singulatiry. The method applies to more general geometries where the singular behavior would be difficult to avoid by classical means.

• 대한수학회지
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• 제49권4호
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• pp.855-865
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• 2012

Recently, we have introduced a group invariant, which is related to the number of elements $x$ and $y$ of a finite group $G$ such that $x{\wedge}y=1_{G{\wedge}G}$ in the exterior square $G{\wedge}G$ of $G$. This number gives restrictions on the Schur multiplier of $G$ and, consequently, large classes of groups can be described. In the present paper we generalize the previous investigations on the topic, focusing on the number of elements of the form $h^m{\wedge}k$ of $H{\wedge}K$ such that $h^m{\wedge}k=1_{H{\wedge}K}$, where $m{\geq}1$ and $H$ and $K$ are arbitrary subgroups of $G$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.951-952
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• 2011

발전소에 설치된 대용량 발전기는 고정자 권선을 지지하기 위해 축 방향으로 삽입된 슬롯 Wedge의 지지압력이 느슨해지면 절연파괴와 같은 각종 사고가 발생할 수 있다. 이를 예방하기 위해 주기적으로 Wedge 조임 상태를 점검하고 있으나 그동안 작업자의 손가락 감각으로 평가하던 방법을 가속도 진동 센서를 이용하여 주파수 스펙트럼을 분석함으로써 발전기 고정자 Wedge 조임 상태를 객관적으로 판정할 수 있도록 방법을 고안하였다.

• 대한수학회지
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• 제47권4호
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• pp.735-742
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• 2010

In this paper, we define and study the concept of $\wedge^s_{\delta}$-closure operator and the associated topology $\tau^{\wedge}^s_{\delta}$ on a topological space (X, $\tau$) in terms of g.$\wedge^s_{\delta}$-sets.

• 호남수학학술지
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• 제38권2호
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• pp.425-433
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• 2016

In this paper, we study face and flag information of a generalized wedge of two polytopes over a face. In particular, we provide the explicit formula for the cd-index of the wedge of a polytope and a one-dimensional simplex over an arbitrary face.

• Radiation Oncology Journal
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• 제3권2호
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• pp.145-151
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• 1985

Wedge filter를 사용할 때 $^{60}Co\;\gamma$선과 10MV X-선의 주변선량분포를 반자동식 물팬톰장치에 의해 제어되는 고체 방사선검출기로 측정하였다. wedge filter의 날과 등의 방향을 잇는 주단면상에서 주변선량을 측정하였다. 방사선의 투과력과 wedge 각, wedge에 대한 방향, 조사면의 변화에 대하여 주변선량의 면화를 고찰하였다. 선축에 수직인 방향의 측정은 깊이 dm, 5cm, 10cm, 15cm에서 선측과 평행인 방향에서는 조사면 경계에서 3cm, 5cm, 10cm 떨어진 위치에서 측정이 이루어졌다. 측정으로부터 wedge가 사용되는 조사면에 대한 주변선량분포가 아래와 같음을 볼 수 있었다. 1. wedge filter의 날의 방향의 주변선량이 등의 방향의 주변선량보다 높았다. 2. 표면근처에서는 깊이가 깊어짐에 따라 선량이 감소하였다. 3. $^{60}Co\;\gamma$선의 경우 어떤 깊이에서는 조사면의 경계로부터 거리가 떨어짐에 따라 주변선량이 단조감소하지 않고 다시 증가하는 영역이 있었다. 4. wedge를 사용하는 경우 주변선량은 방사선의 투과력이나 조사면의 크기뿐만 아니라 wedge의 각과 방향에도 영향을 받는다.

• 한국의학물리학회지:의학물리
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• 제28권2호
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• pp.45-48
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• 2017

This paper evaluated the amount of radiation generated by wedge filters during radiation therapy using a high-energy linear accelerator, and the dose to the worker during wedge replacement. After 10-MV photon beam was irradiated with wedge filter, the wedge was removed from the linear accelerator, and the dose rate and energy spectrum were measured. The initial measurement was approximately 1 uSv/h, and the radiation level was reduced to 0.3 uSv/h after 6 min. The effective half-life derived from the dose rate measurement was approximately 3.5 min, and the influence of AI-28 was about 53%. From the energy spectrum measurements, a peak of 1,799 keV was measured for AI-28, while the peak for Co-58 was not measured in the control room. The peaks for Au-106 and Cd-105 were found only measurement was done without wedge removement from the linear accelerator. The additional doses received by the radiation worker during wedge replacement were estimated to be 0.08-0.4 mSv per year.

• Design & Manufacturing
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• 제11권2호
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• pp.25-28
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• 2017

Semiconductor equipment manufacturers desire to enhance efficiency of Sub Fab to increase semiconductor productivity. For this reason, Sub Fab equipment manufacturers are developing Integrated System that combined modules with multiple facilities. Integrated System is required to apply Mount Leveler of Wedge Type in compliance with weight increase compared with existing single equipment and product shape change. This thesis analyzes main design variables of components of Wedge Mount Leveler and carries out structure analysis using ANSYS, finite element analysis program Analysis shows that main design variables of components of Wedge Mount Leveler has self-locking condition by friction force of Wedge and adjusting bolt. Each friction force hinges upon Wedge angle and Friction Coefficient of contact surface and upon the thread angle and Friction Coefficient of contact surface. Also, as a result of carrying out structure analysis of Wedge Mount Leveler, deflection and stress appears in different depending on the height of the level.

• 한국자동차공학회논문집
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• 제24권1호
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• pp.16-23
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• 2016

The EWB(electronic wedge brake) is one in which the braking force is developed in a wedge and caliper system and applied to a disk and wedge mechanism. The advantage of the wedge structure is that it produces self-reinforcing effect and hence, utilizes minimal motor power, resulting in reduced gear and current. The extent of use of clamping force sensors and protection from failure of the EWB system directly depends on the level of vehicle mass production. This study investigated the mathematical equations, simulation modeling, and failsafe control algorithm for the clamping force sensor of the EWB and validated the simulations. As this EWB system modeling can be applied to motor inductance, resistance, screw inertia, stiffness, and wedge mass and angle, this study could improve the accuracy of simulation of the EWB. The simulation results demonstrated the braking force, motor speed, and current of the EWB system when the driver desired to the step and pulse the brake force inputs. Moreover, this paper demonstrated that the proposed failsafe control algorithm accurately detects faults in the clamping force sensor, if any.