• Proceedings of the Korean Magnestics Society Conference
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• 1997.11a
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• pp.96-97
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• 1997

• The Journal of Korean Physical Therapy
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• v.29 no.4
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• pp.153-157
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• 2017

Purpose: The purpose of this study was to investigate the effect of self-postural control on foot pressure in subjects with forward head posture. Methods: Forty-two healthy adults were recruited in this study. Participants were divided into two groups: The forward-head postural (FHP) group (craniovertebral angle<$53^{\circ}$, n=22) and the control group (craniovertebral angle${\geq}53^{\circ}$, n=20). In the FHP group, foot pressure was measured using three different standing postures: Comfortable standing posture (CSP), subjective neutral standing posture (SNSP), and neutral standing posture with visual feedback (NSP-VP). Each position was performed in random order. In the control group, foot pressure was measured only using the comfortable standing posture. Results: With respect to CSP and SNSP, there was a significant difference on heel pressure between the two groups (p<0.05). Regarding NSP-VP, however, there was no significant differences on heel pressure between the two groups (p>0.05). Conclusion: We suggest that cervical posture control using visual feedback has a positive effect on the distribution of foot pressure in subjects with forward head posture.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.537-550
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• 2014

The actual burden of head and neck cancer in India is much greater than reflected through the existing literature and hence can be regarded as a 'tip of iceberg' situation. This has further been evident by the recent reports of 'Net-based Atlas of Cancer in India'. South-east Asia is likely to face sharp increases of over 75% in the number of cancer deaths in 2020 as compared to 2000. Since the percentage increase of Indian population has been nearly twice that of the world in last 15 years there is a likelihood of increase in cancer burden with the same proportion. The distribution of population based cancer registries is grossly uneven with certain important parts of the country being not represented at all and hence the current cancer burden is not reflected by registry data. However, the pathetic situation of health care system in major parts of the country as also emphasized by the World Bank, is not suitable to provide anywhere near accurate data on cancer burden. Head and neck cancer (including thyroid lesions) is third most common malignancy seen in both the sexes across the globe but is the commonest malignancy encountered in Indian males. Also oral cavity cancer is the most prevalent type amongst the males and one of the highest across the globe. This article reviews the latest global and national situation with an especial emphasis on head and neck cancer. Furthermore this review focuses on burden in different sub sites at national and global levels.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.1
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• pp.1-7
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• 1998

The near field radiated from the monopole antenna of the cellular phone was calculated by using the modified finite difference time domain algorithm derived from the integral form of Maxwell's equations. Substituting the near field value into the differential form of Maxwell's equations, SAR's distribution in the human head was obtained. The human head was simulated by a model of 800,000 block cells with dielectric constant and conductivity. The cell size was taken to be 0.5 cm. the transmitted power of the cellular phone was assumed to be 0.6 watts at the frequency of 833 MHz. The distance between the head and the cellular phone was 2.0 cm, the maximum SAR induced in the human head was about 1.5 W/kg and was below the IEEE's upper safety limit of 1.6 W/kg.

• Korean Journal of Head & Neck Oncology
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• v.19 no.1
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• pp.21-24
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• 2003

Objectives: In this report, we confirmed the distributed pattern of ALA and ALA-methylester in normal and tumor-bearing region. Materials and Methods: ALA and ALA-methylester were administered to nude mouse by intratumoral, subcutaneous and intravenous injection. After injection, the fluorescence in normal and tumor region was measured by LESA (laser electronic spectrum analyzer). Results: The tumor-specificity of ALA and ALA-methylester was shown in the case of intratumoral injection. In all case, the fluorescence caused by ALA and ALA-methylester was maximally increased in 2 hours after injection. Then while the fluorescence level was rapidly decreased to control level in normal region, it was still remained in tumor region. Conclusion: According to this result, The intratumoral injection was more efficient administration method for PDT/PDD than subcutaneous and intravenous injection.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.1
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• pp.90-94
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• 2022

Metal 3D-printing technology enables the manufacture of complex features or internal structures, which is not possible in fabrication by conventional cutting methods. The most successful types of metal 3D printing have been powder bed diffusion and directed energy deposition, which use laser heads exploiting high-power laser sintering metal powder. In this study, a cost-effective optical design was proposed for a 2-kW-level fiber laser head. Only two commercial lenses, a beamsplitter and a window, are used in the laser head, satisfying the technological requirements. According to the optical design, the spot size was 2.54 mm, and the stand-off distance from the laser head was 295 mm. The intensity distribution was Gaussian. Thus, smooth power sintering was possible without any laser spot marks. Monte Carlo analysis was employed to verify the consistency of the optical performance under conventional assembly tolerance.

• Transactions of Materials Processing
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• v.32 no.5
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• pp.268-275
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• 2023

ISO 21029 cryogenic vessel is used to transport cryogenic fluids. High-manganese steel (High-Mn steel) is widely regarded as suitable for use at cryogenic temperatures. The conventional way of manufacturing an ellipsoidal vessel head involves incremental stretching, followed by a spinning process. In this study, an alternative method for forming an ellipsoidal vessel head was proposed. Finite element analysis (FEA) was used to theoretically examine the strain evolution during a multi-stage forming process, which involved progressive stretching, deep drawing, and spinning of High-Mn steel. The distribution of effective strain and strain components were analyzed at different regions of the formed part. The FEA results revealed that only normal strains were evident in the dished region of the vessel head due to the stretching process. However, the flange region experienced complex strain evolution during the subsequent deep drawing and spinning process.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.39-44
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• 2022

Using a CFD (computational fluid dynamics) simulation tool, we have offered a design guideline of a slot-die head having a simple T-shaped cavity through an analysis of the fluid dynamics in terms of cavity pressure and outlet velocity, which affect the uniformity of coated thin films. We have visualized the fluid flow with a transparent slot-die head where poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) is injected. We have shown that the fluid dynamics inside the slot-die head depends sensitively on the cavity depth, cavity length, land length, and channel gap (i.e., shim thickness). Of those, the channel gap is the most critical parameter that determines the uniformity of the pressure and velocity distributions. A pressure drop inside the cavity is shown to be reduced with decreasing shim thickness. To quantify it, we have also calculated the coefficient of variation (CV). In accordance with Hagen-Poiseuille's laws and electron-hydraulic analogy, the CV value is decreased with increasing cavity depth, cavity length, and land length.

• International Journal of Fluid Machinery and Systems
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• v.10 no.2
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• pp.138-145
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• 2017

The problem of non-uniform inflow exists in many practical engineering applications, such as the elbow suction pipe of waterjet pump and, the channel head of steam generator which is directly connect with reactor coolant pump. Generally, pumps are identical designs and are selected based on performance under uniform inflow with the straight pipe, but actually non-uniform suction flow is induced by upstream equipment. In this paper, CFD approach was employed to analyze unsteady hydrodynamic characteristics of reactor coolant pumps with different inflows. The Reynolds-averaged Naiver-Stokes equations with the $k-{\varepsilon}$ turbulence model were solved by the computational fluid dynamics software CFX to conduct the steady and unsteady numerical simulation. The numerical results of the straight pipe and channel head were validated with experimental data for the heads at different flow coefficients. In the nominal flow rate, the head of the pump with the channel head decreases by 1.19% when compared to the straight pipe. The complicated structure of channel head induces the inlet flow non-uniform. The non-uniformity of the inflow induces the difference of vorticity distribution at the outlet of the pump. The variation law of blade to blade velocity at different flow rate and the difference of blade to blade velocity with different inflow are researched. The effects of non-uniform inflow on radial forces are absolutely different from the uniform inflow. For the radial forces at the frequency $f_R$, the corresponding amplitude of channel head are higher than the straight pipe at $1.0{\Phi}_d$ and $1.2{\Phi}_d$ flow rates, and the corresponding amplitude of channel head are lower than the straight pipe at $0.8{\Phi}_d$ flow rates.

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.4
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• pp.769-779
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• 1995

The understanding the nature of occlusal tooth contacts of natural dentition is important for correct diagnosis and treatment of diseases developed in stomatognatic system. Several investigator have studied the distribution of tooth contacts in maximum intercuspation and have repored contact locations with respect to the tooth position. However, there are few report the variation of the occlusal contact point with change in each head position. This study analysed the number of occlusal contact point with change in each head position. 30 subject(male 17, female 13), who ahad natural occlusion and no symptoms of temporomandibular disorder, were selected. The numbers and patterns of tooth contact were recorded by silicone bite registration on stone model at four different head positions with head anguration gauge(from the supine to the upright position). The results obtained were as follows : 1. The numbers of total occlusal contact point on teeth increased to average 25, 29, 35, 42 points as head angulation was changed from the supine to the upright position against the ala-tragus line, and there was significant difference(P<0.05). 2. In the 19 subject(65%)of total 30 subject, the perforated point of the silicone bite indicated that the locus for the prime contact point moved mesially as the head angulation was changed from the supine to the upright position. 3. On the basis of the fact that the anterior occlusal contact point increase as head angulation changed from the supine to the upright position, we could find that the mandibular position is moved anteriorly.