• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.10
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• pp.1899-1909
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• 2007

A cross-coupled charge pump with internal pumping capacitor, witch is advantages from a point of minimizing TFT-LCD driver IC module, is newly proposed in this paper. By using a NMOS and a PMOS diode connected to boosting node from VIN node, the pumping node is precharged to the same value each pumping node at start pumping operation. Since the lust-stage charge pump is designed differently from the other stage pumps, a back current of pumped charge from charge pumping node to input stage is prevented. As a pumping clock driver is located the font side of pumping capacitor, the driving capacity is improved by reducing a voltage drop of the pumping clock line from parasitic resistor. Finally, a layout area is decreased more compared with conventional cross-coupled charge pump by using a stack-MIM capacitors. A proposed charge pump for TFT-LCD driver IC is designed with $0.13{\mu}m$ triple-well DDI process, fabricated, and tested.

• Korean Journal of Remote Sensing
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• v.37 no.5_3
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• pp.1435-1446
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• 2021

Wind and flood damage caused by typhoons causes a lot of damage to the Korean Peninsula every year. In order to minimize damage, a preliminary analysis of damage estimation and evacuation routes is required for rapid decision-making. This study attempted to develop an analysis module that can provide necessary information according to the disaster stage. For use in the preparation stage, A function to check past typhoon routes and past damage information similar to typhoon routes heading north, a function to extract isolated dangerous areas, and a function to extract reservoir collapse areas were developed. For use in the early stages of response and recovery, a function to extract the expected flooding range considering the current flooding depth, a function to analyze expected damage information on population, buildings, farmland, and a function to provide evacuation information were included. In addition, an automated web map creation method was proposed to express the analysis results. The analysis function was developed and modularized based on Python open source, and the web display function was implemented based on JavaScript. The tools developed in this study are expected to be efficiently used for rapid decision-making in the early stages of monitoring against storm and flood damage.

• Tuberculosis and Respiratory Diseases
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• v.82 no.3
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• pp.242-250
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• 2019

Background: Data on noninvasive ventilation (NIV) use in intensive care units (ICUs) are very limited in South Korea. Methods: A prospective observational study was performed in 20 ICUs of university-affiliated hospitals from June 2017 to February 2018. Adult patients (age>18 years) who were admitted to the ICU and received NIV treatment for acute respiratory failure were included. Results: A total of 156 patients treated with NIV were enrolled (mean age, $71.9{\pm}11.6years$). The most common indications for NIV were acute hypercapnic respiratory failure (AHRF, n=89) and post-extubation respiratory failure (n=44). The main device for NIV was an invasive mechanical ventilator with an NIV module (61.5%), and the majority of patients (87.2%) used an oronasal mask. After the exclusion of 32 do-not-resuscitate patients, NIV success rate was 68.5% (85/124); ICU and hospital mortality rates were 8.9% and 15.3%, respectively. However, the success rate was lower in patients with de novo respiratory failure (27.3%) compared to that of patients with AHRF (72.8%) or post-extubation respiratory failure (75.0%). In multivariate analysis, immunocompromised state, de novo respiratory failure, post-NIV (2 hours) respiratory rate, NIV mode (i.e., non-pressure support ventilation mode), and the change of NIV device were significantly associated with a lower success rate of NIV. Conclusion: AHRF and post-extubation respiratory failure were the most common indications for NIV in Korean ICUs. Overall NIV success was achieved in 68.5% of patients, with the lowest rate in patients with de novo respiratory failure.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.1
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• pp.43-55
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• 2019

Smart phone based navigation applications are very useful in everyday life. Cost-effective and user friendly navigation can be provided to the user by many applications available in market. Using the Smart phone these navigation applications provide accurate navigation for outdoor locations. But providing an accurate navigation underground space such as subway station is still a challenge. It is hence more convenient and appropriate for mobility services if the visitors could simply view the guidance of the subway station on their mobile phone, wherever and whenever it is needed. This study develops a algorithm for indoor navigation with the help of Augmented Reality(AR) and QR marker code from the entrance to the train platform for users. This indoor navigation uses AR and QR maker codes for two purposes: to provide the user link to the subway station location and to provide the current guidance details to the user. This Smart phone algorithm that uses a smart phone optical tool to decode the QR marker to determine the location information and provide guidance to the AR without indoor Maps. This algorithm also provides a module to guide mobility vulnerable to the Barrier Free route to destination.

• Journal of the Korea Institute of Building Construction
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• v.19 no.3
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• pp.263-272
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• 2019

Building Information Modeling (BIM) and modular construction are regarded as important technologies that have contributed to advancements in the construction industry. However, the utilization of BIM in current modular construction projects is limited; moreover, there are no specific guidelines pertaining the applications of BIM in modular construction projects. Therefore, this study aims to analyze the utilization of BIM for onsite construction planning in modular construction projects. First, a realistic BIM application was selected through literature review and expert interviews. Then, the construction plan of the modular projects was analyzed to classify the BIM application items into five different categories. The utilization of BIM in each category was then analyzed in terms of necessity and efficiency using a questionnaire. Finally, the BIM Utilization Index (BIM UI) was suggested based on the findings of the survey. As a results, the BIM UI for module point details, lifting plan, other installation details, site layout plan, and schedule plan was 0.811, 0.787, 0.770, 0.729, and 0.699, in the descending order of usability. In addition, through the findings of the study and interviews with experts, a case study for implementation of BIM in modular construction plan was conducted. The results of this study can be used as application guidelines for BIM in future modular construction projects.

• Membrane Journal
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• v.30 no.6
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• pp.443-449
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• 2020

In this study, CO2 separation experiment was performed on a CH4/CO2 mixed gas using a ceramic hollow fiber membrane contactor module (HFMC). In order to fabricate high-durability HFMC, a high-durability hollow fiber membrane was prepared and evaluated. HFMC was fabricated using the prepared hollow fiber membrane, and the experiment used a mixture of CH4/CO2 (30% CO2, CH4 balance) and monoethanolamine (MEA). During HFMC operation, the effect of gas and absorbent pressure on the CO2 removal efficiency was evaluated. The CO2 removal efficiency increased as the gas pressure increased, and the CO2 absorption flux also showed a tendency to increase with the liquid flow rate. In addition, when the CO2 absorption rate was less than 40%, LTS-1, a counter-current form where the absorbent enters from the bottom, has higher CO2 removal performance than LTS-2, a countercurrent form in which the absorbent enters from the top. and when the absorption rate was 40% or higher, LTS-2 had higher performance than LTS-1.

• Journal of Information Technology Applications and Management
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• v.28 no.3
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• pp.59-75
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• 2021

This study aims to establish a foundation for autonomous driving on campus and communication of abundant university information in the HCI environment in a VR environment where college freshmen can freely travel around campus facilities. The purpose of this study is to develop a three-dimensional VR-style campus tour system to establish a media environment to provide abundant university information guidance services to freshmen in non-face-to-face situations. This study designed a three-dimensional virtual reality campus tour system to solve the problem of discontinuity in which VR360 filming space does not lead to space like reality, and to solve many problems of expertise in VR technology by constructing an integrated production environment of tour system. We aim to solve the problem of inefficiency, which requires a large amount of momentum in virtual space, by constructing a GUI that utilizes the motion of the field of view focus. The campus environment was designed as a three-dimensional virtual reality using a three-dimensional graphic design. In non-face-to-face situations, college freshmen freely transformed the HMD VR device, smartphone, FPS operation mode of the gyroscope sensor. The design elements of the three-dimensional virtual reality campus tour system were classified as ①Visualization of factual experiences, ②Continuity of space movement, ③Operation, automatic operation mode, ④Natural landscape animation, ⑤Animation according to wind direction, ⑥Actual space movement mode, ⑦Informatization of spatial understanding, ⑧GUI by experience environment, ⑨Text GUI by building, ⑩VR360, 3D360 Studio Environment, ⑪Three-dimensional virtual space coupling block module, ⑫3D360-3D Virtual Space Transmedia Zone, ⑬Transformable GUI(VR Device Dual Viewer-Gyro Sensor Full Viewer-FPS Operation Viewer) and an integrated production environment was established with each element. It is launched online (http://vautu.com/u1) by constructing a GUI for free driving mode and college information screens to adapt to college life for freshmen, and designing an environment that can be used simultaneously by current media such as PCs, Android, and iPads. Therefore, it conducted user research, held a development presentation, a forum on excellence in university innovation support projects, and applied it as a system on the website of a particular university. College freshmen will be able to experience university information directly from the web and app to the virtual reality campus environment.

• Clean Technology
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• v.27 no.1
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• pp.17-23
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• 2021

Black polymer spacers are currently used for physically separating aligned camera lenses in camera modules of mobile phones. However, the mechanical properties of polymer spacers have their limits, especially in the current trend of using more lenses in thinner camera modules. Thus, copper (Cu) becomes a good candidate for those polymer spacers because of its superior mechanical properties and its inherent blackness due to its black surfaced oxides, such as copper (II) oxide (cupric oxide, CuO). The latter property is critical in quality control because the closer the color of a spacer is to black, the less light interference and flaring phenomena can occur. A standard Cu blackening process and its operational conditions were proposed in this study through a comprehensive analysis of previous research and patents. The Cu blackening process is composed of cleaning, deoxidizing, activating, blackening and sealing. The effects of operational parameters, such as the temperature of each unit process and the activator concentration, were then investigated by measuring the blackness of the Cu strips with a colorimeter. The proposed operational conditions were determined by whether the blackness of Cu strips was within the on-spec. value used in the field.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.5
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• pp.7-15
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• 2022

Since the direct and indirect damage caused by the fire in the underground utility tunnel will cause great damage to society as a whole, it is necessary to make efforts to prevent and control it in advance. The most of the fires that occur in cables are caused by short circuits, earth leakage, ignition due to over-current, overheating of conductor connections, and ignition due to sparks caused by breakdown of insulators. In order to find the cause of fire at an early stage due to the characteristics of the underground utility tunnel and to prevent disasters and safety accidents, we are constantly managing it with a detection system using image analysis and making efforts. Among them, a case of developing a fire detection system using CCTV-based deep learning image analysis technology has been reported. However, CCTV needs to be supplemented because there are blind spots. Therefore, we would like to develop a high-performance acoustic-based deep learning model that can prevent fire by detecting the spark sound before spark occurs. In this study, we propose a method that can collect sound in underground utility tunnel environments using microphone sensor through development and experiment of prototype module. After arranging an acoustic sensor in the underground utility tunnel with a lot of condensation, it verifies whether data can be collected in real time without malfunction.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.1
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• pp.15-22
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• 2022

This paper introduces research on the hinge joint of modular structure joints using finite element analysis. The modular structure has a characteristic in that it is difficult to expect the integrity of columns and beams between unit modules because the construction is carried out such that the modules are stacked. However, the current modular design ignores these structural characteristics, considers the moment transmission for the lateral force, and analyzes it in the same manner as the existing steel structure. Moreover, to fasten the moment bonding, bolts are fastened outside and inside the module, resulting in an unreasonable situation in which the finish is added after assembly. To consider the characteristics that are difficult to expect, such as unity, a modular structure system using hinge joints was proposed. This paper proposed and reviewed the basic theory of joints by devising a modified scissors model that is modified from the scissors model used in other research to verify the transmission of load when changing from the existing moment junction to a hinge junction. Based on the basics, the results were verified by comparing them with Midas Gen, a structural analysis program. Additionally, the member strength and usability were reviewed by changing the modular structure designed as a moment joint to a hinge joint.