• Journal of IKEEE
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• v.23 no.2
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• pp.681-686
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• 2019

This paper proposes a CMOS temperature sensor using inverter delay chains of the same size based on the pulse shrinking method. A temperature-pulse converter (TPC) uses two different temperature delay lines with inverter chains to generate a pulse in proportion to temperature, and a time-digital converter (TDC) shrinks the pulse using inverter chains of the same size to convert pulse width into a digital value to be insensitive to process changes. The chip was implemented with a $0.49{\mu}m{\times}0.23{\mu}m$ area using a $0.35{\mu}m$ CMOS process with a supply voltage of 3.3V. The measurement results show a resolution of $0.24^{\circ}C/bit$ for 9-bit data for a temperature sensor range of $0^{\circ}C$ to $100^{\circ}C$.

• Journal of the Korea Convergence Society
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• v.10 no.8
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• pp.159-164
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• 2019

The front bumper of bobsleigh is mounted to alleviate the impact, but the air resistance to the bobsleigh depends on the body shape positioned in front. This study was conducted the flow analyses about three kinds of bobsleigh configurations. Models B and C with the sharp type of the front can reduce the air resistance than model A with the round type of the front. And the type that the back of the bumper narrows can generate a flow smoother than the one widening. It is thought that the results of this study can be devoted at ensuring the body design to reduce the flow resistance most at bobsleigh. As the design data with the durability of bobsleigh obtained on the basis of this study result are utilized, the esthetic sense can be shown by being grafted onto the machine or structure at real life.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.3
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• pp.503-509
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• 2019

Order-revealing encryption which enables a range query over encrypted data is attracting attention as one of the important security technologies in industry such as IoT, smart manufacturing, and cloud computing. In 2015, an ideally-secure order-revealing encryption whose ciphertexts reveal no additional information beyond the order of the underlying plaintexts has been proposed. However, their construction is too inefficient for practical use and some security analysis of multilinear maps, which their construction relies on, have been proposed. Recently, more practical schemes have been proposed, focusing on achieving practically usable efficiency rather than the ideal security. In this paper, we propose a more storage-efficient order-revealing encryption scheme than the Lewi et al.'s scheme most recently published by presenting an idea that can generate shorter ciphertexts without any security loss.

• Journal of Navigation and Port Research
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• v.43 no.2
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• pp.122-133
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• 2019

The maritime industry has emerged as a new growth engine. The municipalities that own the port are trying to add value through the maritime industry. Overseas port cities are also creating maritime industrial clusters to generate profits and strengthen competitiveness. Therefore, it is very important to understand the comparative status of the domestic maritime industry by region. Based on this analysis, it is possible to establish maritime industrial clusters and strategies for integration. This study analyzed the structure of the maritime industry located in Jeollanamdo province, the southwestern part of Korea. Through the analysis of existing literature, the maritime industry was reclassified into 5 major categories, 21 subcategories, and 84 subcategories. Based on the reclassified maritime industry, the analysis of the Jeollanamdo province maritime industry was based on applying the location quotient and the shift-share analysis. As a result of analyzing the geographical location of Jeollanamdo province, other industries showed the highest value of 2.790, followed by fisheries (2.227), shipbuilding industry (1.164) and marine tourism industry (0.554). The growth effect of the maritime industry in Jeollanamdo province was 35,323 people, and net growth effect excluding national growth effect was 11,945 people. In particular, the net growth effect of the shipbuilding industry was the highest at 11,320, followed by shipping logistics (6,371) and marine tourism (1,529). On the other hand, there was no net growth effect in fisheries. The results of this study can be used as basic data for the construction of the maritime industrial cluster for Jellanamdo province in the future.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.1
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• pp.149-162
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• 2019

The purpose of this study is to suggest various directions of living hanbok and proposed the living hanbok design that integrated the tradition and the contemporary, as well as the past and present with denim material that represents the youth cultureby while using the motif of Korean Jogakbo. For the research method, the data on living hanbok, denim, and Jogakbo were surveyed to develop and produce a living hanbok design. The development of a living hanbok design emphasized the meaning of longing for an accumulation of good fortune, by using the concept of 'wishing for fortune' including the symbolic images of denim and Jogakbo. The production results of this study are as follows. First, the Jogakbo motif consisted of patterns yearning for harmony, great fortune, longevity, and many children, and the living hanbok design integrated with the denim material symbolized the convergence of the past and present and the harmony of eastern and western cultures. The study could verify that the living hanbok design was recreated in a contemporary sense to be used everyday by expressing contemporary senses in a traditional image. Second, leftover fabric pieces and recycled materials that can be abandoned by the material market were used for denim. This study could also develop the living hanbok design as a sustainable design through upcycling, an important social trend, puting an emphasis on carrying out socio-ethical responsibilities. Third, denim Jogakbo work, which is connected by small pieces of denim material, used to be a difficult and labor intensive handicraft, but it could be proposed as a new high value-added fashion and generate contemporary living hanbok with a new image.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.12
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• pp.1698-1704
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• 2018

This paper presents a implementation of a chaotic Lorenz system for data secure communication applications. Here we have used PIC18F family-based microcontroller to generate the chaotic signal, and simulated waveform patterns confirm that the chaotic behavior of the microcontroller based discrete time chaotic Lorenz system. There are three R-2R ladder type A/D converters have been implemented for conversion of direct microcontroller digital output into analog waveform, utilizing this specific microcontroller relevant to this experiment work, microcontroller ports B, C and D have been utilized for its time waveform outputs X, Y and Z respectively. XC8 compiler used for the compilation of the program. MATLAB and PROTEUS software platforms are used for simulation. Finally, chaotic time wave forms, 2D chaotic attractors were obtained and secure communication analog waveforms were also verified by experimental measurement.

• Korea Journal of Hospital Management
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• v.23 no.4
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• pp.53-64
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• 2018

Purposes: The hospitals needs to generate a minimum profit, in order to perform its own role such as providing high-quality medical services. The demand for hospital management is increasing, as the social demands are diversified and the financial transparency is emphasized. The purpose of this study is to compare hospitals management based on Dupont Identity, by various hospital classification. Methodology: This study is based on '2016 Statistics for Hospital Management' provided by the Korea Health Industry Development Institute. The hospitals were classified according to the scope of care, the type of establishment, the location, and the number of beds. We analyzed the general and financial characteristics of over 337 hospitals using the method of Dupont Identity. Findings: Net profit margin (PM) has the biggest impact on return of equity (ROE). By the number of beds, general hospital with 160-299 beds have the highest return on equity (ROE). By location, hospitals in local municipalities have higher return on equity than hospitals in urban municipalities. According to the type of establishment, public hospitals have lower business performance, and although they invest more than private hospitals. Practical Implications: This study can inspire interest and provide understanding in hospital management and financial structure, by analyzing through an intuitive indicator named Dupont identity. It is possible to provide basic data for hospital management methods for each financial elements, in order to increase the profitability of hospitals.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.463-466
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• 2016

Sharing of product and process information with partners is a basic activity and key requirement which ensures success of distribution. ePedigree that encapsulates all of the event data from manufacturer to retail shop provides a flexible mechanism of storing and sharing traceable information to the partners of supply chain and credibility of shared information through digital signature based on Public Key Infrastructure (PKI). To generate the signature that can be authenticated through PKI, the partners of supply chain should pay for PKI certificates from Certificate Authority (CA). In case of agrifood cooperatives which consist of petty merchants or farmers, it is hard to pay for the PKI certificate for all members and is a big obstacle for the ePedigree to be applied to the supply chain. This paper proposes a private certification method of ePedigree for cooperatives. Cooperatives can apply the ePedigree using the proposed method to all the members at small cost and the proposed method can assure the credibility of information at the same level of the previous ePedigree.

• Journal of IKEEE
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• v.23 no.3
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• pp.768-776
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• 2019

With the deployment of 4-th generation industrial revolution, the computer based manufacturing technologies employing advanced IT technology are much more popular than any other past years. In this research, some novel S/W technologies related to the industrial X-ray CT (computed tomography) for the inspection of the industrial parts are introduced. First, newly constructed industrial X-ray CT is presented in this paper, where some basic principles and functions of the CT are described. Then some research platforms are developed to generate more advanced functionalities of the industrial CT. Especially, the data transform from CT to general S/W such as Matlab is conducted. And based on this techniques, some supplementary S/W platform such as GUI (graphical user interface) of the CT S/W and some 3D voxel based image processing technologies can be developed in this paper. The industrial CT is one of the rare research items and it's values can be much more enhanced when it is used with advanced IT technologies.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.243-243
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• 2015

Low-flow simulation and forecasting is one of the emerging issues in hydrology due to the increasing demand of water in dry periods. Even though low-flow simulation and forecasting remains a difficult issue for hydrologists better simulation and earlier prediction of low flows are crucial for efficient water management. The UN has never stated that South Korea is in a water shortage. However, a recent study by MOLIT indicates that Korea will probably lack water by 4.3 billion m3 in 2020 due to several factors, including land cover and climate change impacts. The two main situations that generate low-flow events are an extended dry period (summer low-flow) and an extended period of low temperature (winter low-flow). This situation demands the hydrologists to concentrate more on low-flow hydrology. Korea's annual average precipitation is about 127.6 billion m3 where runoff into rivers and losses accounts 57% and 43% respectively and from 57% runoff discharge to the ocean is accounts 31% and total water use is about 26%. So, saving 6% of the runoff will solve the water shortage problem mentioned above. The main objective of this study is to present the hydrological modelling approach for low-flow simulation and forecasting using a model that have a capacity to represent the real hydrological behavior of the catchment and to address the water management of summer as well as winter low-flow. Two lumped hydrological models (GR4J and CAT) will be applied to calibrate and simulate the streamflow. The models will be applied to Seolmacheon catchment using daily streamflow data at Jeonjeokbigyo station, and the Nash-Sutcliffe efficiencies will be calculated to check the model performance. The expected result will be summarized in a different ways so as to provide decision makers with the probabilistic forecasts and the associated risks of low flows. Finally, the results will be presented and the capacity of the models to provide useful information for efficient water management practice will be discussed.