• The Journal of the Korean bone and joint tumor society
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• v.11 no.2
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• pp.160-167
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• 2005

Purpose : Distal femur and proximal tibia are the common sites affected by giant cell tumor of bone. There are a variety of treatment modality including wide excision and intralesional curettage. We evaluated the local recurrence rates and the post-operative functional scores of giant cell tumors around knee joint and investigated the identification of possible prognostic factors for recurrence. Materials and Methods: We reviewed 41 patients pathologically confirmed as giant cell tumors around knee joint that have undergone intralesional curettage using high-speed burr and methylmethacrylate. We evaluated the recurrence rate and post-surgical functional score and possible prognostic factors for recurrence, such as, gender, age, tumor location, size, subchondral invasion, intra-articular invasion and the Campanacci Grades. Mean follow up period was 50 (12-122) months. Results: The recurrence rate was 17% and mean recurrence onset was 10 months postoperatively. According to Musculoskeletal Tumor Society (MSTS) functional evaluation system, the average score was 27.8(93%) and 78% had excellent function. According to our study, suspected prognostic factors revealed not significant for recurrence. Conclusion: We found no significant recurrence related factors. Intralesional excision with high-sped burring and PMMA provides a low recurrence rate, similar to others in the literature, and good functional scores.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.4
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• pp.759-768
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• 2015

The ground motions of large dimensional structures such as long span bridges at different stations during an earthquake, are inevitably different, which is known as the ground motion spatial variation effect. There are many causes that may result in the spatial variability in seismic ground motion, e.g., the wave passage effect due to the different arrival times of waves at different locations; the loss of coherency due to seismic waves scattering in the heterogeneous medium of the ground; the site amplification effect owing to different local soil properties. In previous researches, the site amplification effects have not been considered or considered by a single-layered soil model only. In this study, however, the ground motion amplification and filtering effects are evaluated by multi-layered soil model. Spatially varying ground motion at the sites with different number of layers, depths, and soil characteristics are generated and the variation characteristics of ground motion time histories according to the correlation of coherency loss function and soil conditions are evaluated. For the bridge system composed of two unit bridges, seismic behavior characteristics are analyzed using the generated seismic waves as input ground motion. Especially, relative displacement due to coherency loss and site effect which can cause the unseating and pounding between girders are evaluated. As a result, considering the soil conditions of each site are always important and should not be neglected for an accurate structural response analysis.

• Molecules and Cells
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• v.43 no.10
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• pp.870-879
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• 2020

Dendrites require precise and timely delivery of protein substrates to distal areas to ensure the correct morphology and function of neurons. Many of these protein substrates are supplied in the form of ribonucleoprotein (RNP) complex consisting of RNA-binding proteins (RBPs) and mRNAs, which are subsequently translated in distal dendritic areas. It remains elusive, however, whether key RBPs supply mRNA according to local demands individually or in a coordinated manner. In this study, we investigated how Drosophila sensory neurons respond to the dysregulation of a disease-associated RBP, Ataxin-2 (ATX2), which leads to dendritic defects. We found that ATX2 plays a crucial role in spacing dendritic branches for the optimal dendritic receptive fields in Drosophila class IV dendritic arborization (C4da) neurons, where both expression level and subcellular location of ATX2 contribute significantly to this effect. We showed that translational upregulation through the expression of eukaryotic translation initiation factor 4E (eIF4E) further enhanced the ATX2-induced dendritic phenotypes. Additionally, we found that the expression level of another disease-associated RBP, fragile X mental retardation protein (FMRP), decreased in both cell bodies and dendrites when neurons were faced with aberrant upregulation of ATX2. Finally, we revealed that the PAM2 motif of ATX2, which mediates its interaction with poly(A)-binding protein (PABP), is potentially necessary for the decrease of FMRP in certain neuronal stress conditions. Collectively, our data suggest that dysregulation of RBPs triggers a compensatory regulation of other functionally-overlapping RBPs to minimize RBP dysregulation-associated aberrations that hinder neuronal homeostasis in dendrites.

• Therapeutic Science for Rehabilitation
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• v.7 no.3
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• pp.79-88
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• 2018

Objective : Localized vibration has been shown to have a positive effect on recovery of upper-limb motor function in patients with hemiparetic stroke, but there has been little research on kinematic analysis for qualitative changes in movement. This study investigated kinematic changes in elbow motion during reaching after localized vibration in persons with hemiparetic stroke. Methods : This study used a one-group, cross-over trial design. Ten chronic stroke patients randomly received localized vibrations on the affected biceps brachii for 5, 10, or 20 min, at 70 Hz. Kinematic analysis of reaching was measured using a 3-D motion analysis system. Variables included peak angular velocity, time to peak angular velocity, and movement units during elbow motion. Result : Affected side elbow motion during reaching was faster, smoother, and more efficient after 20 min localized vibration. Peak angular velocity increased (p<0.05), and time to peak angular velocity (p<0.05) and the movement unit were significantly decreased (p<0.05) during elbow motion for reaching. Conclusion : Localized vibration can improve kinematic components during reaching motion in persons with hemiparetic stroke.

• Korean Journal of Remote Sensing
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• v.33 no.6_3
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• pp.1187-1196
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• 2017

Despite the continuing effort to estimate the value of function and services of ecosystem, most of the researches has used low and medium resolution satellite imagery such as MODIS or Landsat. It means that the researches to measure the ecosystem service value using VHR (Very High Resolution) satellite imagery have not been performed much, while the source of available VHR imagery is increasing. Thus, the aim of this study is to estimate and compare the result of ecosystem service value over Sejong city, S. Korea, which is one of the rapidly changed city, through the pixel-based and object-based classification analysis using VHR KOMPSAT-3 images, for more specific and precise information. In the result of the classification, forest and grassland were underestimated while agriculture and urban were overestimated in the pixel-based result compared to the object-based result. Furthermore, bare soil area was presented contrasting result that was increased in the pixel-based result, however, decreased in the object-based result. Using those results, ecosystem service values were estimated. The annual ecosystem service values in 2014 were $8.18 million USD(pixel-based) and $8.63 million USD(object-based), however, decreased to $7.80 million USD(pixel-based) and $8.62 million USD(object-based) in 2016. It is expected to use those results as a preliminary data when to make sustainable development plan and policy to improve the quality of life in the local level.

• Proceedings of the KOR-KST Conference
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• 1996.02a
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• pp.59-86
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• 1996

Current methods for evaluating unsignalized intersections, and estimating level-of-service (LOS) is determined from efficiency-based criteria such as little or no delay to very long delays. At present, similar procedures to evaluate intersections using safety-based criteria do not exist. The improvement of sight distances at intersections is the most effective way of improving intersection safety. However, a set of procedures is necessary to account for the limitations in current methodology. Such an approach would build upon such methods, but also account for: deficiencies in the current deterministic solution for the determination of intersection sight distances; opportunity for an accident and severity of an accident; and cost-effectiveness of attaining various levels of sight distances. In this research, a model that estimates the degree of safety at two-way stop-controlled intersections is described. Only crossing maneuvers are considered in this study because accidents caused by the crossing maneuvers are the dominate type among intersection accidents. Monte Carlo methods are used to estimate the hazard at an intersection as a function of roadway features and traffic conditions. Driver`s minimum gap acceptance in the crossing vehicles and headway distribution on the major road are used in the crossing vehicles and headway distribution on the major road are used in the model to simulate the real intersectional maneuvers. Other random variables addressed in the model are: traffic speeds; preception-reaction times of both drivers in the crossing vehicles and drivers in oncoming vehicles on the major road; and vehicles on the major roads. The developed model produces the total number of conflicts per year per vehicle and total potential kinetic energy per year per vehicle dissipated during conflicts as measurements of safety at intersections. Based on the results from the developed simulation model, desirable sight distances for various speeds were determined as 350 feet, 450 feet and 550 feet for 40 mph, 50 mph and 60 mph prevailing speed on the major road, respectively. These values are seven to eight percent less than those values recommended by AASHTO. A safety based level-of-service (LOS) is also developed using the results of the simulation model. When the total number of conflicts per vehicle is less than 0.05 at an intersection, the LOS of the intersection is `A' and when the total number of conflicts per vehicle is larger than 0.25 at an intersection, the LOS is `F'. Similarly, when the total hazard per vehicle is less than 350, 000 1b-ft2/sec2, the LOS is `F'. Once evaluation of the current safety at the intersection is complete, a sensitivity analysis can be done by changing one or more input parameters. This will estimate the benefit in terms of time and budget of hazard reduction based upon improving geometric and traffic characteristics at the intersection. This method will also enable traffic engineers in local governments to generate a priority list of intersection improvement projects.

• Radiation Oncology Journal
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• v.36 no.1
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• pp.25-34
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• 2018

Purpose: This study aimed to evaluate the initial outcomes of proton beam therapy (PBT) for hepatocellular carcinoma (HCC) in terms of tumor response and safety. Materials and Methods: HCC patients who were not indicated for standard curative local modalities and who were treated with PBT at Samsung Medical Center from January 2016 to February 2017 were enrolled. Toxicity was scored using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Tumor response was evaluated using modified Response Evaluation Criteria in Solid Tumors (mRECIST). Results: A total of 101 HCC patients treated with PBT were included. Patients were treated with an equivalent dose of $62-92GyE_{10}$. Liver function status was not significantly affected after PBT. Greater than 80% of patients had Child-Pugh class A and albumin-bilirubin (ALBI) grade 1 up to 3-months after PBT. Of 78 patients followed for three months after PBT, infield complete and partial responses were achieved in 54 (69.2%) and 14 (17.9%) patients, respectively. Conclusion: PBT treatment of HCC patients showed a favorable infield complete response rate of 69.2% with acceptable acute toxicity. An additional follow-up study of these patients will be conducted.

• Journal of Chest Surgery
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• v.6 no.2
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• pp.131-142
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• 1973

Studies of cardiopulmonary function and acid-base balance were performed on 29 dogs during control period, during oligemic hypotension and following return of blood to the animals. Intravenous morphine and local anesthesia were used. Fifteen of the 29 animals survived the complete experiment. The 14 animals that failed to survive the experimental period died between 15 to 90 minutes after the onset of bleeding. The results were as follows. 1. The heart rate increased after the onset of bleeding and failed to return to control level following reinfusion. Stroke volume decreased markedly after bleeding and failed to recover after return of blood from the reservoir. Cardiac output also decreased during oligemic hypotension and was maintained at this level after re-infusion. Total peripheral resistance decreased significantly immediately after bleeding, however it increased soon over the pre-bleeding level. Central venous pressure decreased after the onset of bleeding and remained at lower level for the rest of the experimental period. Arterial blood pressure, clown to 40-45 mmHg by acute hemorrhage, was elevated near to control level. Left ventricular work decreased tremendously during oligemic hypotension and failed to return to control level with the re-infusion of blood. Hematocrit value showed no significant decrease after bleeding and increased after re-infusion. Hemoglobin decreased after the onset of bleeding and recovered to control value after re-infusion. 2. The respiratory rate fell rapidly after bleeding from 124 to 29 and remained at this lower level for the remainder of the experiment. The tidal volume increased after bleeding and was maintained at this level for the remainder of the experiment. The respiratory minute volume showed no significant changes throughout the experimental period. Oxygen consumption fell lightly in all animals during oligemic hypotension and returned to normal levels following re-infusion. Arterial oxygen content and arterial oxygen saturation decreased following bleeding and the values returned to normal levels after the return of blood from the reservoir The arterio-venous oxygen difference increased after the onset of bleeding. It failed to return to normal values following re-infusion. Arterial $Pco_2$ decreased in all animals after the beginning of the bleeding. Partial pressure of $Co_2$ continued to fall until re-infusion, after which the values returned toward normal. Animals became acidotic. The pH fell to lower level following bleeding. Lactic acid and lactate: pyruvate ratio also increased during same period. Arterial pH and lactic acid failed to return to control value and lactate: pyruvate ratio increased more after re-infusion. Sodium bicarbonate decreased after bleeding and returned to control value following re-infusion.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3885-3892
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• 2010

Safety-Critical systems, such as Plant Protection Systems in nuclear power plant, plays a key role that the facilities can be operated without undue risk to the health and safety of public and environment, and those systems shall be designed, fabricated, installed, and tested to quality standards commensurate with the importance of the functions to be performed. Computer-based Instrumentation and Control Systems to perform the safety-critical function have Real Time Operating Systems to control and monitoring the sub-system and executing the application software. The safety-critical Real Time Operating Systems shall be designed, analyzed, tested and evaluated to have capability to maintain a high integrity and quality. However, local nuclear power plants have applied the real time operating systems on safety critical systems through Commercial Grade Item Dedication method, and this is the reason of lack of detailed methodology on assessing the safety of real time operating systems, expecially to the new developed one. This paper presents the methodology and experiences of safety evaluation on safety-critical Real Time Operating Systems based upon design requirements. This paper may useful to develop and evaluate the safety-critical Real Time Operating Systems in other industry to ensure the safety of public and environment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04a
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• pp.41-41
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• 2008

In general, polyimides (PIs) are used in alignment layers in liquid crystal displays (LCDs). The rubbing alignment technique has been widely used to align the LC molecules on the PI layer. Although this method is suitable for mass production of LCDs because of its simple process and high productivity, it has certain limitations. A rubbed PI surface includes debris left by the cloth, and the generation of electrostatic charges during the rubbing induces local defects, streaks, and a grating-like wavy surface due to nonuniform microgrooves that degrade the display resolution of computer displays and digital television. Additional washing and drying to remove the debris, and overwriting for multi-domain formation to improve the electro-optical characteristics such as the wide viewing angle, reduce the cost-effectiveness of the process. Therefore, an alternative to non-rubbing techniques without changing the LC alignment layer (i.e, PI) is proposed. The surface of LC alignment layers as a function of the ion beam (IE) energy was modified. Various pretilt angles were created on the IB-irradiated PI surfaces. After IB irradiation, the Ar ions did not change the morphology of the PI surface, indicating that the pretilt angle was not due to microgrooves. To verify the compositional behavior for the LC alignment, the chemical bonding states of the ill-irradiated PI surfaces were analyzed in detail by XPS. The chemical structure analysis showed that ability of LCs to align was due to the preferential orientation of the carbon network, which was caused by the breaking of C=O double bonds in the imide ring, parallel to the incident 18 direction. The potential of non-rubbing technology for fabricating display devices was further conformed by achieving the superior electro-optical characteristics, compared to rubbed PI.