• Journal of the Korean Society for Railway
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• v.12 no.4
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• pp.582-589
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• 2009

The energy generated by braking vehicle would simply be converted into waste heat by its braking resistors if no other vehicle is accelerating at exactly the same time. Up to 45% of the tractive power of vehicles capable of returning energy to the power supply can be regenerated during braking and that this energy can be used to feed vehicles which are accelerating at the same time. Such synchronized braking and accelerating can not be coordinated, the ESS(energy storage system, here after) stores the energy generated during braking and discharges it again when a vehicle accelerates. The ESS is able to store and discharge energy extremely quickly, consequently enabling a complete exchange of energy between vehicles, even if they are not braking and accelerating at precisely the same time, as is most frequently the case in everyday service. The energy saving rate is related to the headway. If the headway is long/short, the energy saving goes up/down, When the headway is short, the ESS can not save much regenerative energy. The headway of SeoulMetro line 2 as the worst case is very short in Korea urban transit system. So, the energy saving rate will be very low. If the ESSs are applied to another railway system, we can expect that the effectiveness is better than the results of SeoulMetro line 2. This paper presents effects of energy saving obtained by applying the ESS to SeoulMetro line 2.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.4
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• pp.153-163
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• 2017

This research is based on the previous research that personally preferred safe distance, rotating angle and speed are differentiated. Thus, we use machine learning model for recognizing maneuvering modes trained per personal or per similar driving pattern groups, and we evaluate automatic driving according to maneuvering modes. By utilizing driving knowledge, we subdivided 8 kinds of longitudinal modes and 4 kinds of lateral modes, and by combining the longitudinal and lateral modes, we build 21 kinds of maneuvering modes. we train the labeled data set per time stamp through RNN, LSTM and Bi-LSTM models by the trips of drivers, which are supervised deep learning models, and evaluate the maneuvering modes of automatic driving for the test data set. The evaluation dataset is aggregated of living trips of 3,000 populations by VTTI in USA for 3 years and we use 1500 trips of 22 people and training, validation and test dataset ratio is 80%, 10% and 10%, respectively. For recognizing longitudinal 8 kinds of maneuvering modes, RNN achieves better accuracy compared to LSTM, Bi-LSTM. However, Bi-LSTM improves the accuracy in recognizing 21 kinds of longitudinal and lateral maneuvering modes in comparison with RNN and LSTM as 1.54% and 0.47%, respectively.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.115-118
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• 2002

Parameters used in a speaker recognition system are desirable expressing speaker's characteristics filly and have in a speech. That is to say, if inter-speaker than intra-speaker variance a big characteristic, it is useful to distinguish between speakers. Also, to make minimum error between speakers, it is required the improved recognition technology as well as the distinguishing characteristics. When we see the result of recent simulation performance, we obtain more exact performance by using dynamic characteristics and constant characteristics by a speaking habit. Therefore we suggest it to solve this problem as followings. The prosodic information is used by a characteristic vector of speech. Characteristics vector generally using in speaker recognition system is a modeling spectrum information and is working for a high performance in non-noise circumstance. However, it is found a problem that characteristic vector is distorted in noise circumstance and it makes a reduction of recognition rate. In this paper, we change pitch line divided by segment which can estimate a dynamic characteristic and it is used as a recognition characteristic. we confirmed that the dynamic characteristic is very robust in noise circumstance with a simulation. We make a decision of acceptance or rejection by comparing test pattern and recognition rate using the proposed algorithm has more improvement than using spectrum and prosodic information. Especially stational recognition rate can be obtained in noise circumstance through the simulation.

• The Journal of Pediatrics of Korean Medicine
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• v.21 no.3
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• pp.109-124
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• 2007

Objectives In the present study, the author intended to investigate whether Gamitonggyu-tang (GTT) significantly affects (since the subject is GTT, you need an 's') in vivo and in vitro mucin secretion from airway epithelial cells. Methods In vivo experiment, mice's mucin which is on a hypersecretion of an airway, mice's tracheal goblet cells in hyperplasia and mice's intraepithelial mucosubstances were exposed with SO2 for 3 weeks. Effects of orally-administered GTT for 1 week on in vivo mucin secretion and hyperplasia of tracheal goblet cells were assessed by using enzyme-linked immunosorbent assay (ELISA) and staining goblet cells with alcian blue. In vitro experiment, confluent hamster tracheal surface epithelial (HTSE) cells were metabolically radiolabeled with 3H-glucosamine for 24 hrs and chased for 30 min in the presence of GTT to figure out the effectiveness of 3H-mucin secretion. Total elution profiles of control spent media and treatment sample through Sepharose CL-4B column were analyzed.Possible cytotoxicities of each agent were assessed by measuring lactate dehydrogenase (LDH) release. Also, the effect of GTT on contractility of isolated tracheal smooth muscle was investigated. Results (1) GTT inhibited hypersecretion of in vivo mucin. However, it did not affect the increase the number of goblet cells (2) GTT significantly increased mucin release from cultured HTSE cells, without significant cytotoxicity (3) GTT chiefly affected the 'mucin' secretion and did not affect the secretion of the other releasable glycoproteins with less molecular weight than mucin (4) GTT did not affect Ach-induced contraction of isolated tracheal smooth muscle.Conclusions This result suggests that GTT can increase mucin secretion during short-term treatment (in vitro) whereas it can inihibit hypersecretion of mucin during long-term treatment (in vivo). The author suggests that the effect GTT with their components should be further investigated and it is valuable to find from oriental medical prescriptions, novel agents which might regulate mucin secretion from airway epithelial cells.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.125-134
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• 2017

Unusual precipitation caused by typhoons and severe rain stormscan threaten human life and property. Thus, various organizations prepare emergency action plans (EAPs) to provide proper guidelines for operators, experts, and emergency response personnel to protect and enhance critical infrastructure. For example, FEMA and DHS have various types of EAPs for dams, levees, and other structures to protect people and property. FEMA defines EAPs as official documents to decrease the damage and impact in emergency situations and to reduce casualties. These documents should consider all possible situations in an emergency and can reduce problems in facility management. This study analyzes EAPs for infrastructure from the USA, Japan, and Korea in order to suggest an ideal EAP framework. EAPcontent can include how to guide experts and operators in disaster stages (mitigation, preparedness, response, and recovery), how to operate emergency equipment, and how to protect critical infrastructure and life. The suggested EAP framework performed very well in a test location. It can therefore be used for infrastructure organizations in Korea and to inform of the appropriate processes and methods for risk reduction in flood disasters.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.4
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• pp.468-475
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• 2019

An end-line flame arrester allows free venting in combination with flame protection for vertical vent applications. End-line flame arresters are employed in various fields, especially in shipping. In flame arresters, springs are essential parts because the spring load and the spring's elasticity determine the hood opening moment. In addition, the spring has to work under a high-temperature condition because of the burning gas flame. Therefore, it is necessary to analyze the mechanical load and elasticity of the spring when the flame starts to appear. Based on simulations of the working process of a specific end-line flame arrester, a thermal and structural analysis of the spring is performed. A three-dimensional model of a burned spring is built using computational fluid dynamics (CFD) simulation. Results of the CFD analysis are input into a finite element method simulation to analyze the spring structure. The research team focused on three cases of spring loads: 43, 93, and 56 kg, correspondingly, at 150 mm of spring deflection. Consequently, the spring load was reduced by 10 kg after 5 min under a $1,000^{\circ}C$ heat condition. The simulation results can be used to predict and estimate the spring's load and elasticity at the burning time variation. Moreover, the obtained outcome can provide the industry with references to optimize the design of the spring as well as that of the flame arrester.

• Journal of IKEEE
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• v.23 no.2
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• pp.743-746
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• 2019

In this paper we proposed a new ocean radiation automatic monitoring system. The proposed system has the following characteristics: First, using NaI + PVT mixed detectors, the response speed is fast and precision analysis is possible. Second, the application of temperature compensation algorithm to scintillator-type sensors does not require additional cooling devices and enables stable operation in the changing ocean environment. Third, since cooling system is not needed, electricity consumption is low, and electricity can be supplied reliably by utilizing solar energy, which can be installed at the observation deck of ocean environment. Fourth, using GPS and wireless communications, accurate location information and real-time data transmission function for measurement areas enables immediate warning response in the event of nuclear accidents such as those involving neighboring countries. The results tested by the authorized testing agency to assess the performance of the proposed system were measured in the range of $5{\mu}Sv/h$ to 15mSv/h, which is the highest level in the world, and the accuracy was determined to be ${\pm}8.1%$, making normal operation below the international standard ${\pm}15%$. The internal environmental grade (waterproof) was achieved, and the rate of variation was measured within 5% at operating temperature of $-20^{\circ}C$ to $50^{\circ}C$ and stability was verified. Since the measured value change rate was measured within 10% after the vibration test, it was confirmed that there will be no change in the measured value due to vibration in the ocean environment caused by waves.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.260-264
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• 2019

An 84-year-old woman presented to the emergency department with a chief complaint of pressure sores of the anus. She had a urine catheter when she showed pyuria three times but had no fever. A microscopic examination revealed many grapevine-like Gram positive strains and neutrophils. After 24 hours of urine culture on blood agar, non-hemolytic mucous colonies were found and further enlarged after 48 hours of culture. The capsules were identified after India ink stain. The catalase was positive, but the tube coagulase and latex coagulase were both negative. The S. aureus was identified by Vitek-2 and mass spectrometer Vitek MS V-3 IVD. The strain was confirmed by 16S rRNA gene sequencing and multilocus sequence typing (MLST). The phenotypically atypical MRSA found in the tube coagulase and latex coagulase were both negative. MRSA often show no beta hemolysis as in this case but are rarely latex coagulase-negative. We report a woman whose urine culture showed non-hemolytic, tube coagulase-negative, and latex coagulase-negative MRSA.

• Therapeutic Science for Rehabilitation
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• v.12 no.3
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• pp.33-44
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• 2023

Objective : The purpose of this study was to identify the risk factors for shoulder pain in manual wheelchair users with spinal cord injuries and to explore the correlation between shoulder pain and quality of life. Methods : Out of 182 participants initially included, 168 were selected for analysis. The questionnaire had 41 questions, with 15 on the Wheelchair User's Shoulder Pain Index (WUSPI) and 26 on the World Health Organization Quality of Life-BREF (WHOQOL-BREF). Results : It was found that participants' scored 50.75 in the WUSPI, whereas they scored higher in mobility and overhead activity. In addition, participants' WHOQOL-BREF scored 70.48, with a mean score of 2.71, which was lower than ordinary adults' WHOQOL-BREF (mean: 3.11) and that of older people suffering from chronic musculoskeletal system pain (total score: 77.92). Conclusion : The participants' WUSPI showed negative correlations with all items, including the total scores on the WHOQOL-BREF. This suggests that the participants' shoulder pain had a negative impact on their quality of life. Therefore, clinical experts, including occupational therapists, should provide manual wheelchair users with spinal cord injuries with programs aimed at preventing and managing shoulder pain, thereby contributing to improving their quality of life.

• Journal of the Korean Society for information Management
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• v.41 no.2
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• pp.295-316
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• 2024

Analyzing research trends is essential for the sustainable development of a discipline and is important for understanding the value of prior research and laying the groundwork for subsequent research. This study aims to draw implications for the future direction of convergence research on the disclosure of information from various disciplines by comparing and analyzing the trends in disclosure of information research in Korea. For this purpose, we analyzed the publication frequency of information disclosure papers listed in the Korea Citation Index (KCI) from 2002 to 2023 and the publication trend by discipline as a time series. In addition, we compared the keyword relationships and specialized research topics of each discipline by applying network analysis and LDA topic modeling techniques to the names and keywords of papers in law, public administration, and library and information science. As a result of the analysis, the law focuses on legal regulations and policy improvement, public administration focuses on changing social needs and administrative operation methods, and LIS focuses on practical approaches to record management and disclosure of information. Based on this, future research directions include combining policy research in law with social change research in public administration and developing realistic policies and operational guidelines from the practical perspective of LIS. Such convergent research will enable the systematic and efficient implementation of disclosure of information systems, contributing to the guarantee of the public's right to know and the enhancement of state transparency.