• Current Optics and Photonics
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• v.3 no.2
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• pp.154-163
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• 2019

In this study, we developed an optical sighting system capable of shooting at a long-distance target by operating a digital gyro mirror composed of a gyro sensor and an FSM. The optical sighting system consists of a reticle part, a digital gyro mirror (FSM), a parallax correction lens, a reticle-ray reflection mirror, and a partial reflection window. In order to obtain the optimal volume and to calculate the leading angle range according to the driving angle of the FSM, a calculation program using Euler rotation angles and a three-dimensional reflection matrix was developed. With this program we have confirmed that the horizontal leading angle of the developed optical sighting system can be implemented under about ${\pm}8^{\circ}$ for the maximum horizontal driving angle (${\beta}={\pm}12.5^{\circ}$) of the current FSM. Also, if the ${\beta}$ horizontal driving angle of the FSM is under about ${\pm}15.5^{\circ}$, it can be confirmed that the horizontal direction leading angle can be under ${\pm}10.0^{\circ}$. If diagonal leading angles are allowed, we confirmed that we can achieve a diagonal leading angle of ${\pm}10.0^{\circ}$ with a vertical driving angle ${\alpha}$ of ${\pm}7.1^{\circ}$ and horizontal driving angle ${\beta}$ of ${\pm}12.5^{\circ}$.

• Clinics in Shoulder and Elbow
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• v.8 no.2
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• pp.170-175
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• 2005

Painful and disabling snapping scapula is an unusual condition and there have been several reports that have revealed good results after surgical treatment for unilateral snapping scapula. We experienced a case of bilateral painful snapping scapula in a young man, but with successful treatment by partial resection of the superomedial angle of both scapula. Preoperative 3-dimensional CT revealed bony prominence of the superomedial angle of both scapula and narrowing between superior scapular angle and chest wall.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.976-979
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• 1992

There are lots of problem which are delaminations and partial discharge of insulation materials in high-voltage rotating machines caused by mechanical, electrical and thermal aging. Several experiments have been aiming at finding the useful diagnostic parameters from the partial discharge characteristics by applying a new measurement techniques. This paper deals with the partial discharge characteristics (pulse height, pulse angle, pulse frequency spectrum and time interval), which may be a useful diagnostic concept in predicting insulation condition of mica/epoxy composite insulation materials, by using several measurement equipments (frequency spectrum analyzer. multichannel analyzer and time interval analyzer).

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.297-305
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• 2006

In this paper, numerical analyses of the flow within turbine for geometric conditions such as nozzle shape, length of axial clearance, and chamfer angle of leading edge of blade have been performed to investigate the partial admission supersonic turbine losses. Firstly, flow's bending occurred at axial clearance is depended on nozzle shape. Next, the chamfer angle of leading edge affects the strength of shock generated at the leading edge. Finally the expansion and mixsing of the flow within axial clearance are largely depended upon the length of axial clearance. Therefore it is found that aerodynamic losses of turbine is affected by nozzle shape and chamfer angel and that partial admission losses is depended on nozzle shape and the length of axial clearance.

• Steel and Composite Structures
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• v.17 no.5
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• pp.667-686
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• 2014

Tapered concrete filled double skin steel tubular (CFDST) columns have been used in China for structures such as electricity transmission towers. In practice, the bearing capacity related to the connection details on the top of the column is not fully understood. In this paper, the experimental behaviour of tapered CFDST stub columns subjected to axial partial compression is reported, sixteen specimens with top endplate and ten specimens without top endplate were tested. The test parameters included: (1) tapered angle, (2) top endplate thickness, and (3) partial compression area ratio. Test results show that the tapered CFDST stub columns under axial partial compression behaved in a ductile manner. The axial partial compressive behaviour and the failure modes of the tapered CFDST stub columns were significantly influenced by the parameters investigated. Finally, a simple formula for predicting the cross-sectional capacity of the tapered CFDST sections under axial partial compression is proposed.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.277-280
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• 2009

Posterior cranial fossa subdural hematomas and extension of the subdural hematoma to the cerebellopontine angle is rarely seen and the concurrent development of acute peripheral facial palsy and the management strategy have not previously been reported in this pathology because of its rarity. We present this case to emphasize that minor head trauma may lead to a posterior cranial fossa hematoma extending to the cerebellopontine angle and cause peripheral facial palsy in patients using aspirin (acetylsalicylic acid). In addition, partial evacuation and waiting for the resorption of the hematoma may help to prevent damage to the 7th and 8th cranial nerves.

• Bulletin of the Korean Chemical Society
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• v.5 no.2
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• pp.68-73
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• 1984

An enhancement of through-bond interaction by bond angle distortion in pyrazine was examined using various MO methods. Results of MINDO/3 geometry optimization with an angle (${\alpha}$) at $C_2$ atom fixed to 120∼90$^{\circ}$ lead to distorted structures in which the distorted bond is brought closer toward lone pair orbital n of N atom. It was also found that the bond angle distortion increased the P character at the atom $C_2$, resulting in an increased vicinal overlap between n and the $C_2-C_3$ bond. The FMO patterns of ${\sigma}$ framework showed three-fold degeneracy, one of which was of different symmetry which mixes in the symmetry adapted pair, $n_+\;and\;n_-;\;both\;n_+\;and\;n_-$ orbitals thus can interact with both FMOs of the ${\sigma}$ framework. The LCBO-MO analysis with partial elimination of bonds, antibonds or both, however, revealed that the main interaction of $n_+$ was with the HO-${\sigma}$ and that of $n_-$ was with the LU-${\sigma}^{\ast}$ orbital of the ${\sigma}$ framework.

• Steel and Composite Structures
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• v.26 no.1
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• pp.67-78
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• 2018

The application of rib stiffeners is common on steel connections, with regard to the stiffened angle connection, experimental results about the influence of stiffeners under monotonic and cyclic loading are very limited. Consequently, this paper presents the experimental investigation on four types angle connections with or without stiffener under static loading and another four type stiffened angle connections subjected to cyclic loading. The static experimental result showed that the rib stiffener weld in tension zone of the connection greatly enhanced its initial rotational stiffness and flexural strength. While a stiffener was applied to the compression zone of the connection, it had not obvious influences on the initial rotational stiffness, but increased its flexural strength. The moment-rotation curves, skeleton curves, ductility, energy dissipation and rigidity were evaluated under cyclic loading. Stiffened top-and-seat angle connections behaved as semi-rigid and partial strength, and rotation of all stiffened angle connections exceeded 0.04rad. The failure modes between monotonic and cyclic loading test were completely different and indicated certain robustness.

• Journal of Korean Foot and Ankle Society
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• v.20 no.4
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• pp.158-162
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• 2016

Purpose: To evaluate the radiological and clinical effects of early weightbearing after distal reverse oblique osteotomy of bunionette. Materials and Methods: Between 2009 and 2015, 52 patients who underwent surgical treatment at our hospital for bunionette deformity with a minimum follow up of one year were included in the study. Postoperatively, foot cast was applied and full weightbearing was permitted in 28 patients. And short leg splint was applied with only partial weightbearing using crutches allowed in 24 patients. Clinical scores were evaluated. Radiologically, the 4th~5th intermetatarsal angle (IMA), and 5th metatarsophalangeal angle (MPA) were analyzed preoperatively and at the final follow up visit. Results: The visual analogue scale and American Orthopaedic Foot and Ankle Society scores improved in the partial weightbearing group and full weightbearing group, but without significant differences. The average 4th~5th IMA and average 5th MPA correction also did not showed significant differences between the partial weightbearing group and full weightbearing group. Moreover, the full weightbearing group did not encourage non-union rate compared with the partial weightbearing group. Conclusion: Effective bone union may be achieved through early weightbearing, resulting in better clinical outcomes. It is considered that early weightbearing did not have any effect on the changes of IMA and bone union.

• Geomechanics and Engineering
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• v.6 no.2
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• pp.99-115
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• 2014

Uncertainties in design variables and design equations have a significant impact on the safety of geotechnical structures like retaining walls and slopes. This paper presents a possible framework for obtaining the partial safety factors based on reliability approach for different random variables affecting the stability of a reinforced concrete cantilever retaining wall and a slope under static loading conditions. Reliability analysis is carried out by Mean First Order Second Moment Method, Point Estimate Method, Monte Carlo Simulation and Response Surface Methodology. A target reliability index ${\beta}$ = 3 is set and partial safety factors for each random variable are calculated based on different coefficient of variations of the random variables. The study shows that although deterministic analysis reveals a safety factor greater than 1.5 which is considered to be safe in conventional approach, reliability analysis indicates quite high failure probability due to variation of soil properties. The results also reveal that a higher factor of safety is required for internal friction angle ${\varphi}$, while almost negligible values of safety factors are required for soil unit weight ${\gamma}$ in case of cantilever retaining wall and soil unit weight ${\gamma}$ and cohesion c in case of slope. Importance of partial safety factors is shown by analyzing two simple geotechnical structures. However, it can be applied for any complex system to achieve economization.