• Korean Journal of Bronchoesophagology
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• v.19 no.1
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• pp.19-24
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• 2013

Objective The objective was to evaluate changes in swallow safety and dietary status after the transcutaneous injection of botulinum toxin into the upper esophageal sphincter in a series of outpatients with dysphagia. Methods Patients who were at risk for aspiration and who had an unsuccessful trial of swallowing therapy were admitted to the study. All patients showed significant pooling of fluids in the pyriform sinus. All patients were treated in the office; none had previous esophageal dilatation. The upper border of the cricoid cartilage was identified using standard electromyogram procedures and botulinum toxin was injected. Outcomes were assessed using the penetration-aspiration scale, NIH swallowiwng safety score, patients' short-term and long-term subjective impressions of their ability to swallow, and change in dietary status. Results Ten patients underwent an instrumental evaluation of swallowing function. Of the 10 patients, 9 showed an overall improvement in their ability to take an oral diet safely. The penetration-aspiration scale, NIH swallowiwng safety score, patients' short-term and long-term subjective impressions of their ability to swallow, and change in dietary status were significantly improved after office-based botox injection. Conclusion Office-based EMG guided botox injection to the cricopharyngeus muscle is a simple, safe, and effective tool for dysphagia patients. Injection of Botox in the office should be considered when the dysphagia pattern is aspiration after swallow.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.185-192
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• 2021

In this study, Full-scale hollow slab Mock-up with VPS(Void Plywood Slab System) was produced. Through Mock-up, the safety of the flat plate hollow slab against short-term sagging and long-term sagging is to be evaluated. The hollow rate of the mock-up specimen to which the hollow core slab was applied was designed to be 24%. When loading through concrete blocks, the most central part of the slab was deflection 8.88mm when loading. However, it shows a safe value compared to the reference value (l_n/240=17.93mm) for short-term deflection. As a result of 3 months of measurement of the mock-up experiment, the deflection at the center of the slab increased by 6.792mm from the initial deflection. In addition, it was found that the reference value by the load used suggested by KBC2016 was satisfied.

• Smart Structures and Systems
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• v.31 no.1
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• pp.45-56
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• 2023

Vibration-based structural health monitoring is used to ensure the safety of structures by installing sensors in structures. The peak picking method, one of the applications of vibration-based structural health monitoring, is a method that analyze the dynamic characteristics of a structure using the peaks of the frequency response function. However, the results may vary depending on the person predicting the peak point; further, the method does not predict the exact peak point in the presence of noise. To overcome the limitations of the existing peak picking methods, this study proposes a new method to automate the modal analysis process by utilizing long short-term memory, a type of recurrent neural network. The method proposed in this study uses the time series data of the frequency response function directly as the input of the LSTM network. In addition, the proposed method improved the accuracy by using the phase as well as amplitude information of the frequency response function. Simulation experiments and lab-scale model experiments are performed to verify the performance of the LSTM network developed in this study. The result reported a modal assurance criterion of 0.8107, and it is expected that the dynamic characteristics of a civil structure can be predicted with high accuracy using data without experts.

• Journal of the Korean Society of Systems Engineering
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• v.19 no.2
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• pp.18-31
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• 2023

Exploring artificial intelligence and machine learning for nuclear safety has witnessed increased interest in recent years. To contribute to this area of research, a machine learning model capable of accurately predicting nuclear power plant response with minimal computational cost is proposed. To develop a robust machine learning model, the Best Estimate Plus Uncertainty (BEPU) approach was used to generate a database to train three models and select the best of the three. The BEPU analysis was performed by coupling Dakota platform with the best estimate thermal hydraulics code RELAP/SCDAPSIM/MOD 3.4. The Code Scaling Applicability and Uncertainty approach was adopted, along with Wilks' theorem to obtain a statistically representative sample that satisfies the USNRC 95/95 rule with 95% probability and 95% confidence level. The generated database was used to train three models based on Recurrent Neural Networks; specifically, Long Short-Term Memory, Gated Recurrent Unit, and a hybrid model with Long Short-Term Memory coupled to Convolutional Neural Network. In this paper, the System Engineering approach was utilized to identify requirements, stakeholders, and functional and physical architecture to develop this project and ensure success in verification and validation activities necessary to ensure the efficient development of ML meta-models capable of predicting of the nuclear power plant response.

• Journal of the Society of Disaster Information
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• v.11 no.4
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• pp.622-633
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• 2015

With recent news reports on violent crimes committed by foreigners, public hatred toward foreign criminals and fear about such crimes are growing, calling into question public safety measures implemented by the police and the immigration system. At the same time, due to globalization and structural changes in the labor market, it is certain that the influx of migrant workers will continue to increase. Against this backdrop, this paper seeks to examine the current status of foreign nationals staying in Korea and their criminal records focusing on Suwon city, and propose public safety measures the police could take with regard to crimes committed by foreigners. Also, the paper looks into public safety measures of the Korea Immigration Service and Suwon city, and suggests short- and long-term measures to prevent crimes committed by foreigners. The paper begins by examining the current public safety measures of the police and Suwon City concerning crimes committed by foreign nationals residing in Korea. Based on such examination, it points out insufficient patrol and investigation personnel as problems, and recommends short- and long-term measures for future improvement. This paper maintains that for the Korean society to successfully deal with the increasing number of foreigners in Korea, the current immigration system and public safety measures of the police will have to change. While the police alone cannot reduce the crime rates at local and national levels, nonetheless, proactive measures by the police are needed given the growing number of migrant workers and immigrants in Korea. Also important are mindset changes not only of relevant authorities, but also of the public. The paper recommends a set of short-and long-term public safety measures the police should institute to efficiently deal with crimes committed by foreigners.

• Journal of Gastric Cancer
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• v.13 no.1
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• pp.44-50
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• 2013

Purpose: Laparoscopic gastrectomy has been adopted for the treatment of gastric cancer, and despite the technical difficulties, totally laparoscopic distal gastrectomy has been considered less invasive than laparoscopy-assisted distal gastrectomy. Although there have been many reports regarding the feasibility and safety of totally laparoscopic distal gastrectomy at large volume centers, few reports have been conducted at low-volume centers. The purpose of this study is to try to assess the feasibility and safety of totally laparoscopic distal gastrectomy at a low volume center through the analysis of short-term outcomes of totally laparoscopic distal gastrectomy compared with laparoscopy-assisted distal gastrectomy. Materials and Methods: The clinical data and short-term surgical outcomes of 35 patients who had undergone laparoscopy-assisted distal gastrectomy between April 2007 and March 2010, and 37 patients who underwent totally laparoscopic distal gastrectomy between April 2010 and August 2012 were retrospectively reviewed. Results: There was no significant difference in the demographic and clinical data. However the reconstruction method and extent of lymphadenectomy showed statistically significant differences. Operation time and estimated blood loss did not show significant differences. Surgical and medical complications did not show significant differences but postoperative courses including time-to-first oral intake and postoperative hospital stay were significantly increased. Conclusions: Our study shows that totally laparoscopic distal gastrectomy is technically feasible at a low volume center. Therefore, totally laparoscopic distal gastrectomy can be considered as one of the surgical treatment for early gastric cancer. However the possibility that totally laparoscopic distal gastrectomy may have less benefit should also be considered.

• Toxicological Research
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• v.29 no.2
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• pp.115-120
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• 2013

To investigate the effects of short-term exposure of beryllium on the human immune system, the proportion of T-lymphocytes such as CD3+, CD4+, CD8+, CD95, and NK cells, and the proportion of B cells and $TNF{\alpha}$ level in peripheral blood and immunoglobulins in the serum of 43 exposed workers and 34 healthy control subjects were studied. External exposure to beryllium was measured by atomic absorption spectrometer as recommended by the NIOSH analytical method 7300. T lymphocyte subpopulation analysis was carried out with flow cytometer. The working duration of exposed workers was less than 3 months and the mean ambient beryllium level was $3.4{\mu}g/m^3$, $112.3{\mu}g/m^3$, and $2.3{\mu}g/m^3$ in molding (furnace), deforming (grinding), and sorting processes, respectively (cited from Kim et al., 2008). However, ambient beryllium level after process change was non-detectable (< $0.1{\mu}g/m^3$). The number of T lymphocytes and the amount of immunoglobulins in the beryllium-exposed workers and control subjects were not significantly different, except for the total number of lymphocytes and CD95 (APO1/FAS). The total number of lymphocytes was higher in the beryllium-exposed individuals than in the healthy control subjects. Multiple logistic regression analysis showed lymphocytes to be affected by beryllium exposure (odd ratio = 7.293; p<0.001). These results show that short-term exposure to beryllium does not induce immune dysfunction but is probably associated with lymphocytes proliferation.

• Architectural research
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• v.20 no.3
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• pp.83-92
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• 2018

Recently, there has been inter-Korean exchanges are active, in company with an assertive international activity with North Korea and inter-Korean Summits. Thus, there is a growing possibility of Korean reunification. However, when the unification situation occurs, population inflow by North Korean residents will be expected, and it will be necessary to prepare a housing supply strategy. In addition, even if North Koreans are prevented from entering, a plan is necessary to ensure structural safety since most buildings in North Korea are aging and a recent natural disaster occurs frequently. In this research, we will try to present a temporary housing supply strategy and a short-term structural reinforcement plan based on analysis of the standard housing conditions in North Korea. In this research, we represent the analysis result of the existing construction level, supply status and structural performance of North Korea. When we consider the reinforcement period and social costs, a short-term reinforcement plan is recommended rather than the full reinforcement of the aged housing in North Korea. Furthermore, we examine the ways to secure the residential safety of North Koreans through a case study of domestic and overseas temporary residential facilities, until the permanent residential facilities were supplied. According to the analysis, the tent houses were used as a form of relief housing in overseas frequently. However, the tent house is difficult to apply for domestic country with clear seasons due to insulation and heating problems. Therefore, it is appropriate to develop a residential supply strategy as focusing on the temporary housing facilities in assembled or container from, in preparation for the future population inflow.

• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.53-58
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• 1998

For evaluating the mutagenic potential of 2-carbomethoxy-4-chlorodiethyl phosphate, three different short-term mutagenicity tests were used; Salmonella typhimurium preincubation assay with and without rat liver microsomal activation, chromosome aberration test in cultured chinese hamster lung fibroblast cell and in vivo micronucleus test in male mice bone marrow. In Salmonella typhimurium reverse mutation assay using TA98, TA100, TAl535 and TAl537, 2-carbomethoxy-4-chlorodiethyl phosphate did not show any mutagenic response in the presence and absence of S9 mix. It did not induce any significant structural chromosome aberrations in the absence of metabolic activation. In micronucleus test using ICR mice, the frequency of micronucleated polychromatic erythrocytes (MNPCE) increased in bone marrow cells treated with positive control, mitomycin-C, but 2-carbomethoxy-4-chlorodiethyl phosphate did not increase micronucleated polychromatic erythrocytes. These results indicate that 2-carbomethoxy-4-chlorodiethyl phosphate does not show any positive responses in short-term genotoxicity assays.

• Journal of Energy Engineering
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• v.14 no.2 s.42
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• pp.153-158
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• 2005

In order to investigate the short-term performance of polyethylene electrofusion joints, the mechanical tests and stress analysis have been conducted to the artificially defected weld joints. The defects of lack of fusion with a square-type were fabricated with 10, 20, 30, 40, 50, 60$\%$ size of the width of heat-ing wire zone, respectively. In this defect sires range, both tensile and bending test results showed the dependence of defect size to the electrofusion joints performance, but both sustained pressure and crush test results didn't. The numerical stress analysis results including the soil and internal pressures, tensile and bend-ing stresses clearly showed the dependence of fusion defect size. Based on both mechanical test and stress analysis results, the maximum acceptable defect size in polyethylene electrofusion joints is discussed.