• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.2
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• pp.137-146
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• 2001

Route selection needs the analysis function of GSIS to analyze and manipulate a lot of spatial information efficiently. Therefore, it needs the linkage of system requiring the knowledge and the experience of experts as a method that can estimate each quantitative route for an efficient route selection. In this study, the route selection model through construction and analysis procedure of position information using GSIS were presented, and route selection system linked with expert system was developed. This system is easy to be used and managed for presenting route alignment according to conditions as a graphic user interface environmental window system by applying three tiers based object-oriented method. Using GSIS, the various information required for route selections in database was constructed, the characteristics of subject area by executing three-dimensional terrain analysis was grasped effectively, and the control point through buffering, overlay and location operation was extracted. Three alternative routes between a beginning point and an end point inputted by route selection system were selected. Therefore, the applications of the route selection system are presented by applying this system to the real study area.

• Journal of Korean Foot and Ankle Society
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• v.6 no.2
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• pp.156-160
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• 2002

Purpose: To analyze the clinical outcome of triple arthrodesis for the posttraumatic arthritis after calcaneal fractures. Materials and Methods: We retrospectively reviewed 22 posttraumatic arthritis patients who underwent a triple arthrodesis from March 1991 to May 1998. The mean duration of follow up was 74 months(range, 36-123 months). The pain, function and alignment were evaluated by the modified ankle-hindfoot scale of the American Orthopaedic Foot and Ankle Society(AOFAS) clinically and the union rate, the duration of union and the degenerative change of adjacent joints radiographically were evaluated. Results: The mean duration from injury to arthrodesis was 33 months (range, 12-132 months). The AOFAS score improved from 36.4 points(range, 14-64) preoperatively to 67.6(range, 25-90) postoperatively. The union rate was 90.1% radiographically, the mean duration of union was 14.3 weeks(range, 12-21 weeks) and the degenerative change in the adjacent joint was showed in 12 patients(54.5%). There were 2 cases of talonavicular nonunion, one superficial wound infection and one partial skin necrosis. Conclusion: Triple arthrodesis for posttraumatic arthritis after calcaneal fractures is a useful method for relief of pain and correction of posttraumatic hindfoot deformity, as an evidenced by the satisfactory clinical outcome. Although a high prevalence of subsequent arthritis of the ankle and midtarsal joint was noted radiographically, we found that it was not clinically relevant.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.487-501
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• 1998

In the case of CAD/CAM ceramic inlay restorations, if isthmus width is widened too much, it may cause fracture of remaining tooth structure or loss of bonding at the luting interface because of excessive displacement of buccal or lingual cusps under occlusal loads. So to clarify the criterior of widening isthmus width, this study was designed to test the tensile bond strength and bond failure mode between dentin and ceramic cemented with luting composite resin cements. Cylindrical ceramic blocks(Vita Cerec Mark II, d=4mm) were bonded to buccal dentin of 40 freshly extracted third molars with 4 luting composite resin cements(group1 : Scotchbond Resin Cement/Scotchbond Multi-Purpose, group2 : Duolink Resin Cement/ All-Bond 2, group3: Bistite Resin Cement/Ceramics Primer, and group4:Superbond C&B). Tensile bond test was done under universal testing machine using bonding and measuring alignment blocks(${\phi}ilo$ & Urn, 1992). After immersion of fractured samples into 1 % methylene blue for 24 hours, failure mode was analysed under stereomicroscope and SEM. Results: The tensile bond strength of goup 1, 2 & 4 was $13.97{\pm}2.90$ MPa, $16.49{\pm}3.90$ MPa and $16.l7{\pm}4.32$ MPa, respectively. There was no statistical differences(p>0.05). But, group 3 showed significantly lower bond stregnth($5.98{\pm}1.l7$ MPa, p<0.05). In almost all samples, adhesive fractures between dentin and resin cements were observed. But, in group 1, 2 & 4, as bond strength increased, cohesive fracture within resin cement was observed simultaneously. And, in group 3, as bond strength decreased, cohesive fracture between hybrid layer and composite resin cement was also observed. Cohesive fracture within dentin and porcelain adhesive fracture were not observed. In conclusion, although adhesive cements were used in CAD/CAM -fabricated ceramic inlay restorations, the conservative priciples of cavity preparation must be obligated.

• Macromolecular Research
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• v.16 no.3
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• pp.212-217
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• 2008

PVDF ($Kynar^{(R)}$ 761) nanofibers were made by electrospinning with an external voltage of 6-10 kV, a traveling distance of 7-15 cm and a flow rate of 0.4-1 mL/h. Although the mean diameter of the fibers has not changed significantly, the conditions affected the change in diameter distribution. This was attributed to interactions, both attraction and repulsion, between the positive charges on the polymer solutions and the electrically grounded collector. Higher voltages and traveling distance increased the level of attraction between the positive charge on the polymer solution and the electrically grounded collector, resulting in a narrow diameter distribution, In addition, a high flow rate allowed a high population of uniformly charged solutions to travel to the grounded collector, which resulted in a narrow diameter distribution. The optimum conditions for electrospinning of PVDF in DMAc/acetone (3/7 by wt) were a collector voltage of 6 kV, a syringe tip to collector of 7 cm, a flux rate of 0.4 mL/h and 10 kV, 10 cm, 1 mL/h, Since PVDF is widely used as a filtration membrane, it was electrospun on a PET support with a rotating drum as a grounded collector. Surprisingly, some straight nanofibers were separated from the randomly deposited nanofibers. The straight nanofiber area was transparent, while the randomly deposited nanofiber area was opaque. Both straight nanofibers and aligned nanotibers could be obtained by manipulating the PET drum collector. These phenomena were not observed when the support was changed to an Al sheet. This suggests that a pseudo dual collector was generated on the PET sheet. No negative charge was created because the PET sheet was not a conductive material. However, less charge was created when the sheet was not perfectly attached to the metal drum. Hence, the nanotibers jumped from one grounded site to the nearest one, yielding a straight nanofiber.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.5
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• pp.568-573
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• 2019

Modern Radars are evolving into MFRs which can search multiple targets simultaneously and then track them. Additionally they should be able to avoid some external jamming signals. Applying to these MFRs, Antennas should be able to perform DBF including to not only real-time beam steering but also multi-beam forming simultaneously. And they can cancel the beam at the specific direction. In this paper, we describe the implementation of sub-array type antenna hardware which can be applying DBF. Also we propose the modified amplitude aperture distribution for suppressing the side lobe level and explain the sub-array receiver design with amplitude tapering. It consists in making the amplitude weighting in 2 steps. In order to compare two weighting cases, we investigate the G/T performance for the array antenna. At the conclusion, we make a comparative study for the dynamic range of every sub-array receiver and present the hardware implementation that is more advantageous for sub-array alignment and calibration in DBF.

• Physical Therapy Korea
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• v.26 no.2
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• pp.1-7
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• 2019

Background: In previous studies, changes in postural alignment were found when the slope was changed during walking. Downhill walking straightens the trunk by shifting the line of gravity backward. Objects: This study investigated the effect of the downhill treadmill walking exercise (DTWE) on thoracic angle and thoracic erector spinae (TES) activation in subjects with thoracic kyphosis. Methods: A total of 20 subjects with thoracic kyphosis were recruited for this study. All the subjects performed the DTWE for 30 minutes. A surface EMG and 3D motion capture system were used to measure TES activation and thoracic angle before and after the DTWE. Paired t-tests were used to confirm the effect of the DTWE (p<.05). Results: Both the thoracic angle and TES activation had significantly increased after the DTWE compared to the baseline (p<.05). An increase in the thoracic angle indicates a decrease in kyphosis. Conclusion: The DTWE is effective for thoracic kyphosis patients as it decreases their kyphotic posture and increases the TES activation. Future longitudinal studies are required to investigate the long-term effects of the DTWE.

• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.639-643
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• 2021

In this study, fluorinated ethylene propylene (FEP) nanoparticle as an adhesive for fabricating a three-dimensional multilayered microfluidic device was studied. The formation of evenly distributed FEP nanoparticles layer with 3 ㎛ in thickness on substrates was achieved by simple spin coating of FEP dispersion solution at 1500 rpm for 30 s. It is confirmed that FEP nanoparticles transformed into a hydrophobic thin film after thermal treatment at 300 ℃ for 1 hour, and fabricated polyimide film-based microfluidic device using FEP nanoparticle was endured pressure up to 2250 psi. Finally, a three-dimensional multilayered microfluidic device composed of 16 microreactors, which are difficult to fabricate with conventional photolithography, was successfully realized by simple one-step alignment of FEP coated nine polyimide films. The developed three-dimensional multilayered microfluidic device has the potential to be a powerful tool such as high-throughput screening, mass production, parallelization, and large-scale microfluidic integration for various applications in chemistry and biology.

• Archives of Plastic Surgery
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• v.48 no.1
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• pp.69-74
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• 2021

Background In inferomedially rotated zygomatic fractures sticking in the maxillary sinus, it is often difficult to achieve complete reduction only by conventional intraoral reduction. We present a new intraoral reduction technique using a Kirschner wire and its clinical outcome. Methods Among 39 inferomedially impacted zygomatic fractures incompletely reduced by a simple intraoral reduction trial with a bone elevator, a Kirschner wire (1.5 mm) was vertically inserted from the zygomatic body to the lateral orbital rim in 17 inferior-dominant rotation fractures and horizontally inserted to the zygomatic arch in nine medial-dominant and 13 bidirectional rotation fractures. A Kirschner wire was held with a wire holder and lifted in the superolateral or anterolateral direction for reduction. Following reduction of the zygomaticomaxillary fracture, internal fixation was performed. Results Fractures were completely reduced using only an intraoral approach with Kirschner wire reduction in 33 cases and through an additional lower lid or transconjunctival incision in six cases. There were no surgical complications except in one patient with undercorrection. Postoperative 6-month computed tomography scans showed complete bone union and excellent bone alignment. Four patients experienced difficulty with upper lip elevation; however, these problems spontaneously resolved after manual tissue lump massage and intralesional steroid (Triamcinolone) injection. Conclusions We completely reduced infraorbital rim fractures, zygomaticomaxillary buttresses, and zygomaticofrontal suture fractures in 84% of patients through an intraoral approach alone. Intraoral Kirschner wire reduction may be a useful option by which to obtain effective and powerful reduction motion of an inferomedially rotated zygomatic body.

• Journal of Advanced Navigation Technology
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• v.22 no.2
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• pp.57-63
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• 2018

In the case of aircraft-launched guided weapons, various interface tests such as MIL-STD-1760 based power source, discrete signal, MUX communication as well as BIT of missile can verify system safety and reliability. The purpose of this case study is to develop a test bench based on MIL-STD-1760E for interoperability testing between aircraft and weapons. We proposed a testing method of the launch sequence based on the defined TIME LINE in the development phase of the missile system from the application of the power of the missile to the targeting, the transfer order, and the missile separation process. Furthermore, it will be a reference model that can maximize the verification scope in the development phase of the air to surface missile system by simulating abnormal situation to the inert missile using the error insertion function.

• Journal of Ginseng Research
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• v.46 no.3
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• pp.481-488
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• 2022

Background: Although the tumor-suppressive effects of ginsenosides in cell cycle have been well established, their pharmacological properties in mitosis have not been clarified yet. The chromosomal instability resulting from dysregulated mitotic processes is usually increased in cancer. In this study, we aimed to investigate the anticancer effects of ginsenoside Rg1 on mitotic progression in cancer. Materials and methods: Cancer cells were treated with ginsenoside Rg1 and their morphology and intensity of different protein were analyzed using immunofluorescence microscopy. The level of proteins in chromosomes was compared through chromosomal fractionation and Western blot analyses. The location and intensity of proteins in the chromosome were confirmed through immunostaining of mitotic chromosome after spreading. The colony formation assays were conducted using various cancer cell lines. Results: Ginsenoside Rg1 reduced cancer cell proliferation in some cancers through inducing mitotic arrest. Mechanistically, it inhibits the phosphorylation of histone H3 Thr3 (H3T3ph) mediated by Haspin kinase and concomitant recruitment of chromosomal passenger complex (CPC) to the centromere. Depletion of Aurora B at the centromere led to abnormal centromere integrity and spindle dynamics, thereby causing mitotic defects, such as increase in the width of the metaphase plate and spindle instability, resulting in delayed mitotic progression and cancer cell proliferation. Conclusion: Ginsenoside Rg1 reduces the level of Aurora B at the centromere via perturbing Haspin kinase activity and concurrent H3T3ph. Therefore, ginsenoside Rg1 suppresses cancer cell proliferation through impeding mitotic processes, such as chromosome alignment and spindle dynamics, upon depletion of Aurora B from the centromere.