• Radiation Oncology Journal
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• v.18 no.2
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• pp.150-156
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• 2000

Purpose : Stereotactic radiation therapy (SRT) can deliver highly focused radiation to a small and spherical target lesion with very high degree of mechanical accuracy. For non-spherical and large lesions, however, inclusion of the neighboring normal structures within the high dose radiation volume is inevitable in SRT This is to report the beam shaping using the partial closure of the independent jaw in SRT and the verification of dose calculation and the dose display using a home-made soft ware. Materials and Methods : Authors adopted the idea to partially close one or more independent collimator jaw(5) in addition to the circular collimator cones to shield the neighboring normal structures while keeping the target lesion within the radiation beam field at all angles along the arc trajectory. The output factors (OF's) and the tissue-maximum ratios (TMR's) were measured using the micro ion chamber in the water phantom dosimetry system, and were compared with the theoretical calculations. A film dosimetry procedure was peformed to obtain the depth dose profiles at 5 cm, and they were also compared with the theoretical calculations, where the radiation dose would depend on the actual area of irradiation. Authors incorporated this algorithm into the home-made SRT software for the isodose calculation and display, and was tried on an example case with single brain metastasis. The dose-volume histograms (DVH's) of the planning target volume (PTV) and the normal brain derived by the control plan were reciprocally compared with those derived by the plan using the same arc arrangement plus the independent collimator jaw closure. Results : When using 5.0 cm diameter collimator, the measurements of the OF's and the TMR's with one independent jaw set at 30 mm (unblocked), 15.5 mm, 8.6 mm, and 0 mm from th central beam axis showed good correlation to the theoretical calculation within 0.5% and 0.3% error range. The dose profiles at 5 cm depth obtained by the film dosimetry also showed very good correlation to the theoretical calculations. The isodose profiles obtained on the home-made software demonstrated a slightly more conformal dose distribution around the target lesion by using the independent jaw closure, where the DVH's of the PTV were almost equivalent on the two plans, while the DVH's for the normal brain showed that less volume of the normal brain receiving high radiation dose by using this modification than the control plan employing the circular collimator cone only. Conclusions : With the beam shaping modification using the independent jaw closure, authors have realized wider clinical application of SRT with more conformal dose planning. Authors believe that SRT, with beam shaping ideas and efforts, should no longer be limited to the small spherical lesions, but be more widely applied to rather irregularly shaped tumors in the intracranial and the head and neck regions.

• Journal of Korean Society of Transportation
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• v.17 no.3
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• pp.61-70
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• 1999

The Purpose of this study is to test whether Braess Paradox (BP) can be revealed in a real world network. Fer the study, Namsan 2nd tunnel case is chosen, which was shut down for 3 years for repair works. The revelation of BP is determined by analyzing network-wise traffic impacts followed by the tunnel closure. The analysis is conducted using a network simulation model called SECOMM developed for the congestion management of the Seoul metropolitan area. Also, the existence of BP is further identified by a before-after traffic survey result of the major arterials nearby the Namsan 2nd tunnel. The model estimation expected that the closure of Namsan 2nd tunnel improve the network-wise average traffic speed from 21.95km/h to 22.21km/h when the travel demand in the study area and congestion Pricing scheme on Namsan 1st & 3rd tunnels remain unchanged. In addition, the real world monitoring results of the corridors surrounding Namsan 2nd tunnel show that the average speed increases from 29.53km/h to 30.37km/h after the closure. These findings clearly identify the BP Phenomenon is revealed in this case.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.4
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• pp.163-172
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• 2022

This study investigates the IPI (Information Protection Intention) of DHS (Digital Healthcare Service) providers by introducing PMT (Protection Motivation Theory). This study examines the effects of protection motivation, such as threat appraisal and coping appraisal, on IPI, such as ICI(Induction Control Intention) and SDI(Self Defense Intention). The research model, based on the PMT, adopted severity, vulnerability, reaction efficacy and self-efficacy as independent variables. The research model was validated through quantitative research, a survey of 222 DHS providers in South Korea, using structural equation modeling. The results show that (1) a clear awareness of the consequences of security threats increases the understanding of DHS providers on the severity of closure of healthcare information, and thus may decreases abuse of DHS by providers; (2) user confidence and satisfaction on the security system may make them be confident that they can handle the closure of healthcare information by themselves; and (3) although DHS providers are realizing the consequences of closure of healthcare information, they think that they are unlikely to encounter such situations. As a result of this study, venture companies that provide DHS need to provide contents that can continuously increase providers' security level in order to increase providers' information protection intention. It suggests that IPI is important through trust of healthcare service providers.

• Structural Monitoring and Maintenance
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• v.3 no.4
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• pp.315-333
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• 2016

This study aims to perform damage identification for Da-Sheng-Guan (DSG) high-speed railway truss arch bridge using fuzzy clustering analysis. Firstly, structural health monitoring (SHM) system is established for the DSG Bridge. Long-term field monitoring strain data in 8 different cases caused by high-speed trains are taken as classification reference for other unknown cases. And finite element model (FEM) of DSG Bridge is established to simulate damage cases of the bridge. Then, effectiveness of one fuzzy clustering analysis method named transitive closure method and FEM results are verified using the monitoring strain data. Three standardization methods at the first step of fuzzy clustering transitive closure method are compared: extreme difference method, maximum method and non-standard method. At last, the fuzzy clustering method is taken to identify damage with different degrees and different locations. The results show that: non-standard method is the best for the data with the same dimension at the first step of fuzzy clustering analysis. Clustering result is the best when 8 carriage and 16 carriage train in the same line are in a category. For DSG Bridge, the damage is identified when the strain mode change caused by damage is more significant than it caused by different carriages. The corresponding critical damage degree called damage threshold varies with damage location and reduces with the increase of damage locations.

• Journal of Environmental Policy
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• v.8 no.1
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• pp.129-143
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• 2009

In South Korea, Mine industries were encouraged to obtain the natural resource from 1960 to 1980. However, the depletion of natural resource and decreasing price have been caused by the voluntary closure of non-economical mines and a cut of their production since 1990. Harmful wastewater containing such heavy metals as iron, aluminum, arsenic, and cadmium are being discharged from abandoned pits and waste stone and tailing dumping sites following the closure of mines. Therefore, the objective of this paper suggests a policy of mine hazard prevention(PMHP) and method that allows the combination of new spatial data and as well as collected data on resources for the sustainable mine reclamation and management using EGIS/MGIS technique to develop an integrated plan and management techniques.

• Journal of The Korean Dental Society of Anesthesiology
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• v.1 no.1 s.1
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• pp.26-31
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• 2001

The wide deep penetrating wound of maxillofacial region should be early closed under emergency general anesthesia for the prevention of complications of bleeding, infection, shock & residual scars. But, if the emergency general anesthesia wound be impossible because of pneumoconiosis, obstructive pulmonary disease & hypovolemic shock, early primary closure should be done under local anesthesia by use of much amount of the anesthetic solution. The maximum dose of dental lidocaine (2% lidocaine with 1 : 100,000 epinephrine) is reported to 7 mg/kg under 500 mg (13.8 ampules) in normal adult. But the maximum permissible dose of dental lidocaine can be changed owing to the general health, rapidity of injection, resorption, distribution & excretion of the drug. The blood level of overdose toxicity is above $4.0{\mu}g/ml$ in central nervous & cardiovascular system. The injection of dental lidocaine 1-4 ampules is attained to the blood level of $1{\mu}g/ml$ in normal healthy adult. The duration of anesthetic action in the dental 2% lidocaine hydrochloride with 1 : 100.000 epinephrine is 45 to 75 minutes and the period to elimination is about 2 to 4 hours. Therefore, authors selected the following anesthetic methods that the first injection of 6 ampules is applied into the deeper periosteal layer for anesthetic action during 1 hour, the second injection into the deeper muscle & fascial layer, the third injection into the superficial muscle and fascial layer, the fourth injection into the proximal skin & subcutaneous tissue and the fifth final injection into the distal skin & subcutaneous tissue. The total 26-28 ampules of dental lidocaine were injected into the wound as the regular time interval during 5-6 hours, but there were no systemic complications, such as, agitation, talkativeness, convulsion and specific change of vital signs and consciousness.

• The Journal of Korean Physical Therapy
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• v.27 no.3
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• pp.140-146
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• 2015

Purpose: To determine the effects of 630 nm light emitting diode (LED) on full-thickness wound healing. Methods: Twelve male Sprague-Dawley rats were randomly divided into LED (n=6) and control group (n=6). Two $19.63mm^2$ wounds were created on the mid dorsum. LED group received a 630 nm LED irradiation with $3.67mW/cm^2$ for 30 minutes ($6.60J/cm^2$) for 7 days, while control group received sham LED irradiation. Epithelial gap, collagen density, ${\alpha}$-SMA fibroblast and PCNA keratinocyte were measured on histochemical and immunohistochemical staining using image analysis system. An independent t-test was conducted to compare the difference between groups. Results: The wound closure rate, collagen density, ${\alpha}$-SMA fibroblast number, epithelial gap and PCNA keratinocyte number have shown no significant difference between LED and control group at day 3 after the treatment. At day 7 after the treatment, the wound closure rate in LED group was increased when compared with control group (p<0.05). The collagen density (p<0.05) and ${\alpha}$-SMA immunoreactive fibroblast number (p<0.001) were increased when compared with control group at day 7. The epithelial gap in LED group was significantly shorten than control group at day 7 (p<0.01). The PCNA positive cell number in LED group was higher than control group at day 7 (p<0.01). Conclusion: 630 nm LED with $3.67mW/cm^2$, $6.60J/cm^2$ accelerate collagen deposition by stimulating fibroblasts, and enhance wound contraction by differentiating myofibroblasts in the dermis, and accelerate keratinocyte proliferation by facilitating DNA synthesis in the epidermis. It may promote the healing process in proliferation stage of wound healing.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.3
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• pp.197-208
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• 2016

The WCPFC CMMs related to tropical tunas have been strongly restricting fishing capacity and operating activities of main fisheries, especially purse seine fishery. In terms of changes in fishing trend by implementing relevant measures of FAD set, the number of FAD set by Korean purse seine fleet showed a decreasing pattern with the lowest level of FAD set proportion among major distant water fishing nations. With regards to the FAD closure, there was no significant change in fishing effort but a drop in catch, especially bigeye tuna during the period of FAD closure. Moreover, it showed closely similar trends between the number of FAD set and bigeye tuna catch. In terms of measures related to the high sea area including a ban on fishing on the HSP and limitation of fishing days on the high sea by flag state, proportions of catch and effort on the high sea had sharply declined after implementing those measures. As relevant measures are expected to be strengthened, it should pay attention to change of coastal nations policies and focus on improving fishing efficiency of unassociated school set with multi-pronged efforts.

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.4
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• pp.565-572
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• 1994

According to the classification of dental arch form and the analysis of patterns of chewing movement, the patterns of chewing movement in each group were evaluated and compared with those of the normal group. Results were summarized as follows ; 1. Opening phase in chewing movement In the group which the maxillary second molar positionsbuccal side, the chewing patterns which have the Vertical Guide Openings in frontal plane, the Posterior Guide Openings in hjorizontal plane were observed. In the group which the maxillary premolars position lingual side, the chewing paterns which have the Protrusive Shift Openings in horizontal plane and sagittal plane were observed. 2. Closing phase in chewing movement. In each group except for the normal group, the chewing patterns which have the Concave Closure in frontal plane and in Horizontal plane were observed. In the group which the maxillary premolars position buccal side, the chewing patterns which have the Lateral Guide Closure in frontal plane and in horizontal plane, the Vertical Guide Closre in sagittal plane were observed: From the results, as the characteristics of the dental arch form have appeared in chewing movement, the close relationships were found between dental arch form and chewing movement. It is suggested that the evaluation of dental arch form is effective in the diagnosis of function of stomatognathic system.

• Journal of Gastric Cancer
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• v.24 no.1
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• pp.108-121
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• 2024

Anastomotic leaks and fistulas are significant complications of gastric surgery that potentially lead to increased postoperative morbidity and mortality. Surgical intervention is reserved for cases with severe symptoms or hemodynamic instability; however, surgery carries a higher risk of complications. With advancements in endoscopic treatment options, endoscopic approaches have emerged as the primary choice for managing these complications. Endoscopic clipping is a traditional method comprising 2 main categories: through-the-scope clips and over-the-scope clips. Through-the-scope clips are user friendly and adaptable to various clinical scenarios, whereas over-the-scope clips can close larger defects. Another promising approach is endoscopic stent insertion, which has shown a high success rate for leak closure, although vigilant monitoring is required to monitor stent migration. Infection control is essential in post-surgical leakage cases, and endoscopic internal drainage provides a relatively safe and noninvasive means to manage fluids, contributing to infection control and wound healing promotion. Endoscopic suturing offers full-thickness wound closure, but requires additional training and endoscopic versatility. As a promising tool, endoscopic vacuum therapy potentially surpasses stent therapy by draining inflammatory materials and closing defects. Furthermore, the use of tissue sealants, such as fibrin glue and cyanoacrylate, has been reported to be effective in selected situations. The choice of endoscopic device should be tailored to individual cases and specific patient conditions, with careful consideration of the nature of the defect. Further extensive studies involving larger patient populations are required to provide more robust evidence on the efficacy of endoscopic approach in managing post-gastric anastomotic leaks.