• Clinical Endoscopy
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• v.56 no.6
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• pp.769-777
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• 2023

Background/Aims: Endoscopic submucosal dissection (ESD) for superficial non-ampullary duodenal tumors (SNADETs) is associated with a high rate of en bloc resection. However, the technique for ESD remains challenging. Recent studies have demonstrated the effectiveness of S-O clips in colonic and gastric ESD. We evaluated the efficacy and safety of duodenal ESD using an S-O clip for SNADETs. Methods: Consecutive patients who underwent ESD for SNADETs between January 2011 and December 2021 were retrospectively enrolled. Propensity score matching analysis was used to compare patients who underwent duodenal ESD with the S-O clip (S-O group) and those who underwent conventional ESD (control group). Intraoperative perforation rate was the primary outcome, while procedure time and R0 resection rate were the secondary outcomes. Results: After propensity score matching, 16 pairs were created: 43 and 17 in the S-O and control groups, respectively. The intraoperative perforation rate in the S-O group was significantly lower than that in the control group (p=0.033). A significant difference was observed in the procedure time between the S-O and control groups (39±9 vs. 82±30 minutes, respectively; p=0.003). Conclusions: The S-O clip reduced the intraoperative perforation rate and procedure time, which may be useful and effective in duodenal ESD.

• Journal of IKEEE
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• v.15 no.1
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• pp.15-22
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• 2011

In order to performing the joint operation of Korean army efficiently, informations about surveillance, reconnaissance, and situation awareness need to be possessed jointly. In the first development phase (basis type) of the Korean joint tactical data link system (JTDLS-K), essential tactical information and recognized situation are owned among platforms in common by using existing wireless terminals. In the second development phase (completion type) of the JTDLS-K, a JTDLS which can perform network centric warfare (NCW) will be developed in due consideration of technology development of the basis type and common technology maturity degree. This is a joint battlefield system that can show fighting power simultaneous and polysynthetically through providing command and control messages effectively to each platform, which is participating in the joint and combined operations. In this paper, the development of JTDLS-K with a common data processor based on common link integration processing (CLIP) is described. From the test results of the system presented in this paper, it is demonstrated that quadrature phase shift keying (QPSK) signals can be applied to the system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.11
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• pp.1026-1033
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• 2004

Clipping is a simple and convenient PAPR reduction method to prevent the high-speed OFDM communication system from the nonlinear distortion. However, it inherently produces clip noise so that BER performance can be degraded. Clipping noise can be divided into in-band and out-of-band clipping noise. In this paper, we study the clipping effect on the forward link of the OFDM-FDMA system. BER performance of OFDM-FDMA system using clipping method is theoretically analyzed. We also investigate the BER performance of the clipped OFDM-FDMA signal through the HPA. From the simulation results it can be quantified how much the BER performance of OFDM-FDMA system is degraded by the clipping method. From the study results, we can choose the appropriate IBO value and CR(clip ratio) to get the desired BER performance.

• The KIPS Transactions:PartB
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• v.11B no.1
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• pp.35-44
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• 2004

Web contents created for desktop screens give rise to problems when they are to be displayed on the small screens of mobile terminals. While in some cases some of the objects of a page may not be displayable due to the lack of browser capability, the entire page may not be displayable due to the incompatibility with the browser in other cases. In this paper, we introduce a new mobile content adaptation approach based on web clipping, which transforms an original page into one that is optimally displayed on a mobile terminal. In this method, a source page is automatically clipped and transformed according to the clip specification made by the content provider using a clip editing tool. The clip editing tool allows the user to specify group clips, multi-level cups and dynamic clips as well as simple clips, and the presentation layout through a graphic user interface. Based on the clip specifications, each clip is transformed into an intermediate meta-language document, which in turn is transformed into a presentation page in the target markup language. Transcoding of image objects in major image file formats is also supported.

• Journal of Korean Neurosurgical Society
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• v.44 no.5
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• pp.314-319
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• 2008

Objective: For patients with giant or dissecting aneurysm, multimodal treatment consisting extracranial-intracranial bypass surgery plus clip or coil for parent artery occlusion may be necessary. In this study, the safety and efficacy of multimodal treatment in 15 patients with complex aneurysms were evaluated retrospectively. Methods: From January 1995 to June 2007, the authors treated 15 complex aneurysms that were unable to be clipped or coiled. Among them, nine patitents had unruptured aneurysms and 6 had ruptured aneurysms. Aneurysms were located in the internal cerebral artery (ICA) in 11 patients (4 in the dorsal wall. 4 in the terminal ICA, 1 in the paraclinoid, and 2 in the cavernous ICA), in the middle cerebral artery (MCA) in 2, and in the posterior circulation in two patients Results: Fifteen patients with complex aneurysms were treated with bypass surgery previously. Thirteen patients were treated with external carotid middle cerebral artery (ECA-MCA) anastomosis, and one patient with superficial temporal to posterior cerebral artery (STA-PCA) and another patient with occipital artery to posterior inferior cerebellar artery (OA-PICA) anastomosis. Parent artery occlusion was then performed with a clip in 9 patients, with a coil in 4, with balloon plus coil in one patient. All 15 aneurysms were successfully treated with clip or coil combined with bypass surgery. Follow-up angiograms showed good patency of anastomotic site in 10 out of 11 patients, and perfusion study showed sufficient perfusion in 6 out of 9 patients. Conclusion: These findings indicate that for patients with complex aneurysms, clip or coil for parent vessel occlusion with additive bypass surgery can successfully exclude the aneurysm from the neurovascular circulatory system.

• Composites Research
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• v.15 no.1
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• pp.41-52
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• 2002

This paper presents the thermo-elastic analysis for searching the behavior of carbon/carbon brake system during the braking period and the 3-D stress analysis to find the shape of the brake disk which is safe to the failure. The mechanical properties of the carbon/carbon brake disk were measured for both in-plane and out of plane directions. The mechanical properties were used as the input of the thermo-elastic analysis and 3-dimensional stress analysis for the brake disk. The gap between rotor clip and clip retainer is an important parameter in the loading transfer mechanism of the rotor disk. The change of gap was considered both the mechanical deformation and thermal deformation. Because the rotor clip and clip retainers were not contacted, they were excluded from the analysis model. Rotor disk was modeled by using the cyclic symmetry condition. The contact problems between rotor clip and key drum as well as between rotor disk and rotor were considered. From the results of the 3-D stress analysis, the stress concentration at the key hole of the brake disk was confirmed. The stress distributions were studied thor the variation of the rotation angle of the contact surface and the radius of curvature at the key hole part.

• Archives of Plastic Surgery
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• v.42 no.1
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• pp.78-83
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• 2015

In perforator flap reconstruction, vascular mapping using preoperative computed tomography (CT) angiography is widely used to confirm the existence and location of an appropriate perforator. This study proposes a rapid, accurate, and convenient method for marking the perforator location on the skin surface. For 12 patients who underwent perforator flap reconstruction between November 2011 and November 2013, metal clips were fixed on the skin surface at the anticipated perforator locations, which were decided using a handheld Doppler. CT angiography was used to compare the location between the metal clip and the actual perforator. The metal clip was moved and repositioned, if needed, on the basis of the CT images. The locations of the appropriate perforator and the metal clip, which were observed during the surgery, were then compared. In CT angiography, the mean distance between the metal clip and the perforator was $3{\pm}3.9mm$, and the mean distance that was measured during surgery was $0.8{\pm}0.8mm$. In conclusion, we report a simple, rapid, and precise technique to indicate the accurate location of the appropriate perforator on the skin surface.

• Journal of Biomedical Engineering Research
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• v.35 no.4
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• pp.99-104
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• 2014

Generally, human eye blinks are closely associated with the cognitive state or visual attention such as attentional requirements on visual stimuli. These previous studies have reported that eye blinks are related to explicit visual attention using blink rate, pattern and blink timing across subjects. However, these results have been obtained in a well-controlled experimental settings. So, it would prove difficult to investigate human's natural response in a continuous and realistic situation. In our study, we measured the eye blink intervals while participants viewed a movie clip. And we analyzed the blink interval data for relationship between visual attention and eye blink intervals. 24 participants took part in two experimental sessions, first session to measure the IEBI while viewing the movie clip and second session to conduct a memory performance test using a self-questionnaire, which were spaced 3 weeks apart. The results indicate significantly higher memory performance at long IEBI period than short IEBI period while watching a movie clip(t = 3.257, df = 17, p < 0.005, 2-tailed). In addition, memory performance score significantly correlated with the IEBI value(spearman's rho = 0.40, N = 36, p < 0.01, 2-tailed). Our results suggest that IEBI is used to measure or assess visual attention while wiewing the movie that it is capable of simulating aspects of real-life experiences by visual attention. Thus, we expect IEBI to be used to measure or assess our visual attention, cognition, further emotion about not only movies, advertisements and other cultural contents but also cognitive science.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.175-186
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• 2010

When a rigid post is exposed to traffic, it is hazardous not only to head-on impacts but also to side impacts. Clip-type slip base is an effective measure to reduce the severity of head-on impacts and side impacts as well because of its multi-directional release mechanism. Side impact tests were conducted and the results were analysed to demonstrate the hazardousness of a rigid post to a side impact and the crash worthiness of a post having clip-type slip base. For that, side impact test standard was made adapting the NCHRP Report 350, and 820kg-50km/h side impact tests were made for posts of D101.6mm(t=4.2mm) with and without slip base. Additionally, 35km/h side impact to the same post with slip base was conducted to check whether the clip-type slip base release mechanism works properly to the low impact speed. The tests revealed that the rigidly connected post was very hazardous to side impact while the post with the clip-type slip base reduced the impact severity tremendously.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup1
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• pp.73-78
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• 2001

Objective : Intraoperative rupture of an intracranial aneurysm can interrupt a microsurgical procedure and jeopardize the patient's chance to favorable outcome. The purpose of this study was to analyse and evaluate intraoperative aneurysmal rupture and render ideal prevention and management to intraoperative rupture. Patients and Methods : The authors retrospectively analysed the results of 609 patients who underwent cerebral aneurysm surgery from January 1991 to December 2000. Results : 1) Intraoperative aneurysmal rupture occurred in 73 of 609 consecutive aneurysm surgery, so the incidence was about 12.0% and it was relatively lower than other reports. 2) Aneurysms arising from anterior communicating artery appeared more prone to intraoperative rupture. 3) The size of aneurysm and timing of operation didn't influence intraoperative aneurysmal rupture and temporary clipping didn't reduce the incidence of intraoperative aneurysmal rupture. 4) Intraoperative aneurysmal rupture occured during three specific periods : (1) dissection stage in 61%, (2) clip application stage in 29 %, (3) predissection stage in 10%. 5) In the patients with intraoperative aneurysmal rupture, surgical outcome was relatively good and there was no significant difference in outcome compared with unruptured group. Conclusion : Our suggestion for prevention methods of intraoperative aneurysmal rupture are as follows : 1) minimal brain retraction, 2) sharp and careful aneurysmal neck dissection, 3) gentle clipping with proper clip selection etc. Management methods after intraoperative aneurysmal rupture are as follows : 1) strong aspiration of bleeding point, 2) rapid application of temporary and/or tentative clip, 3) following rapid dissection of neck and proper clip application, 4) use of encircling clip etc.