• Journal of the Korean Solar Energy Society
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• v.31 no.2
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• pp.53-62
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• 2011

Heliostat in the tower type solar thermal power plant is a sun tracking mirror system to reflect the solar energy to the receiver and the optical performance of it affects to the efficiency of whole power plant most significantly. Thus a proper design of structure of the heliostat reflective surface could be the most important step in the construction of such power plant. The work presented here is a design of structure of optical surface of heliostat, which will be used in 200kW solar thermal power plant. The receiver located at 43(m) high from ground in tower has $2{\times}2$(m) rectangular shape. We first developed the software tool to simulate the energy concentration characteristics of heliostat using the ray tracing technique. Then, the shape of heliostat reflective surface is designed with the consideration of heliostat's energy concentration characteristics, production cost and productivity. The designed heliostat's reflective surface has a structure formed by canting four of $1{\times}1$(m) rectangular flat plate mirror facet and the center of each mirror facet is located on the spherical surface, where the spherical surface is formulated by the mirror facet mounting frame.

• Korean Journal of Optics and Photonics
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• v.10 no.6
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• pp.500-506
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• 1999

We designed and fabricated a bidirectional optical transceiver module for low cost access network. An integrated chip forming a pin-PD on an 1.3 urn FP-LD was assembled by flip-chip bonding on a Si optical bench, a single mode fiber with an angled end facet was aligned passively with the integrated chip on V-groove of Si-optical bench. Gaussian beam theory was applied to evaluate the coupling coefficients as a function of some parameters such as alignment distance, angle of fiber end facet, vertical alignment error. The theory is also used to search the bottle-neck between transmittance and receiving coupling efficiency in the bi-directional optical system. Tn this paper, we confirmed that reduction of coupling efficiency by the vertical alignment error between laser beam and fiber core axis can be compensated by controlling the fiber facet angle. In the fabrication of sub-module, a'||'&'||' we made such that the fiber facet have a corn shape with an angled facet only core part, the reflection of transmitted laser beam from the fiber facet could be minimized below -35 dE in alignment distance of 2: 30 /J.m. In the same condition, transmitted output power of -12.1 dEm and responsivity of 0.2. AIW were obtained.

• Journal of the Korean Society for Library and Information Science
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• v.43 no.3
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• pp.197-219
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• 2009

The study acknowledges the need for classification systems in arts and cultural education. The study constructs a faceted classification system for this domain based on systematic methods. The study utilized iterative collaboration between domain experts and classification system developers. The classification system consists of 13 main facets and terms. The classification system has values to manage information resources effectively and efficiently. It is also beneficial for reducing cultural gaps in arts and cultural education as well as providing an information gateway for users.

• Journal of Korean Foot and Ankle Society
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• v.11 no.2
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• pp.226-231
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• 2007

Purpose: To evaluate the clinical outcomes and radiographic results of open reduction and internal fixation for intraarticular calcaneal fractures. Materials and Methods: We reviewed 20 cases of calcaneal fractures managed with open reduction and internal fixation from March 2003 to January 2005. We used the computed tomographic classification system proposed by Sanders et al to classify these fractures. Preoperative and postoperative Bohler's angle, heel height (calcaneal facet height) and calcaneal length, calcaneal width were measured. The Creighton-Nebraska Health Foundation Assessment score was used for clinical evaluation. Results: There were 12 cases of type II fractures, 5 of type III fractures and 3 of type IV fractures. The mean clinical score was 84.3 for type II, 82.6 for type III and 56.1 for type IV. The mean preoperative $B{\ddot{o}}hler$ angle was $6.1^{\circ}$ and final was $22.8^{\circ}$. The mean preoperative calcaneal facet height was 76.6 mm and final was 80.3 mm (The mean calcaneal facet height was changed from preop 76.6 mm to postop 80.3 mm). The mean preoperative calcaneal length was 88.2 mm and final was 92.6 mm. The mean preoperative width was 38.1 mm and final was 35.6 mm. Conclusion: Open reduction and internal fixation showed good results for type II and III fractures, but for type IV fractures the clinical result was significantly worse than the other types. However, type IV fractures still had restoration of (should be restored in) $B{\ddot{o}}hler's$ angle, calcaneal facet height, calcaneal length and width which may be helpful in later subtalar fusion.

• Journal of the Korean Society for information Management
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• v.37 no.2
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• pp.225-249
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• 2020

The purpose of this study is to identify and systematize various facet elements required by users in fiction search situations from book tags to improve the fiction search environment. Based on the Ranganathan's PMEST formula, the basic facet system of the fiction was defined as 1) the personality that forms the fiction material, 2) the content and external characteristics that compose the fiction, 3) the reader interaction with books, 4) spatial information related to fiction and reading activities, and 5) time information related to fiction and reading activities. Out of approximately 310,000 tags assigned to 7,174 fiction, 3,730 core tags were selected and content-analyzed. As a result, various attributes were systematized around the top 25 categories of the fiction facets. The results of this study can be applied to facet navigation of OPAC and fiction DB in the future.

• Journal of Korean Neurosurgical Society
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• v.59 no.2
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• pp.91-97
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• 2016

Objective : To investigate the biomechanical effects of a newly proposed Interspinous Process Compressor (IPC) and compare with pedicle screw fixation at surgical and adjacent levels of lumbar spine. Methods : A three dimensional finite element model of intact lumbar spine was constructed and two spinal fusion models using pedicle screw fixation system and a new type of interspinous devices, IPC, were developed. The biomechanical effects such as range of motion (ROM) and facet contact force were analyzed at surgical level (L3/4) and adjacent levels (L2/3, L4/5). In addition, the stress in adjacent intervertebral discs (D2, D4) was investigated. Results : The entire results show biomechanical parameters such as ROM, facet contact force, and stress in adjacent intervertebral discs were similar between PLIF and IPC models in all motions based on the assumption that the implants were perfectly fused with the spine. Conclusion : The newly proposed fusion device, IPC, had similar fusion effect at surgical level, and biomechanical effects at adjacent levels were also similar with those of pedicle screw fixation system. However, for clinical applications, real fusion effect between spinous process and hooks, duration of fusion, and influence on spinous process need to be investigated through clinical study.

• Journal of Korea Multimedia Society
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• v.13 no.10
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• pp.1436-1443
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• 2010

In vocabulary recognition system has it's bad points of processing vocabulary unseen triphone and then no got distribution of confidence measure by cannot normalization. According to this problem to improve suggested VCOR(Version Control for Out-of Rejection) system by out-of vocabulary rejection algorithm use vocabulary management optimization and then phone data search support. In VCOR system to provide vocabulary information efficiently offering for user's vocabulary information using extend facet classification that improved for vocabulary measure management function offering accuracy of recognition for vocabulary. In this paper proposed system performance as a result of represent vocabulary dependence recognition rate of 97.56%, vocabulary independence recognition rate of 96.23%.

• Journal of the Korea Society of Computer and Information
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• v.15 no.2
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• pp.127-134
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• 2010

In continuous vocabulary recognition system by probability distribution of clustering method has used model parameters of an advance estimate to generated each contexts for phoneme data surely needed but it has it's bad points of gaussian model the accuracy unsecure of composed model for phoneme data. To improve suggested probability distribution mixed gaussian model to optimized that phoneme data search supported configuration thread system. This paper of configuration thread system has used extension facet classification user phoneme configuration thread information offered gaussian model the accuracy secure. System performance as a result of represent vocabulary dependence recognition rate of 98.31%, vocabulary independence recognition rate of 97.63%.

• Journal of Korean Foot and Ankle Society
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• v.6 no.2
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• pp.149-155
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• 2002

Purpose: To propose a new comprehensive classification system of intraarticular calcaneal fracture based on CT images. Materials and methods: Fourty intraarticular calcaneal fractures which were treated operatively were evaluated retrospectively. We classified fracture types according to severity of comminution on the posterior facet and calcaneocuboid joint by CT images. And we evaluated postoperative results of each fracture types in terms of the quality of fixation and reduction by the postoperative plain radiograghs. Results: By the classification of the posterior facet, 18 cases were P-I, 15 were P-II, and 7 were P-III. Among the P-I cases, 7 were P-IA, 9 were P-IL, 1 was P-IM and 2 were P-IT. According to the classification of calcaneocuboid joint, II cases were C-I, 18 were C-II and 11 were C-III. Qualities of fixation were excellent in 27 cases (67.5%), fair in 9(22.5%) and poor in 4(10%). Qualities of reduction were excellent 23 cases(57.5%), fair in 11(27.5%) and poor in 6(15%). Conclusion: Our new classification system based on the CT images could provide informations about the fracture configuration and severity of comminution around calcaneocuboid joint as well as the posterior facet. And the high grade fractures such as type P-III are need to be taken care of fixation of articular surfaces.

• Spatial Information Research
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• v.12 no.2
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• pp.137-149
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• 2004

For 3D modelling artificial objects with computers, we have to draw frames and paint the facet images on each side. In this paper, a geographic modelling system building automatically 3D geographic spaces using GIS data and real images of buildings is proposed. First, the 3D model of terrain is constructed by using TIN and DEM algorithms. The images of buildings are acquired with a camera and its position is estimated using vertical lines of the image and the GIS data. The height of the building is computed with the image and the position of the camera, which used for making up the frames of buildings. The 3D model of the building is obtained by detecting the facet iamges of the building and texture mapping them on the 3D frame. The proposed geographical modeling system is applied to real area and shows its effectiveness.