• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.3
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• pp.184-196
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• 2020

In this paper, a single-bit 2nd-order delta-sigma modulator with the architecture of cascaded-of-integrator feedforward (CIFF) is proposed for precision measurement of current flowing through a secondary cell battery in a battery management system (BMS). The proposed modulator implements two switched capacitor integrators and a single-bit comparator with peripheral circuits such as a non-overlapping clock generator and a bias circuit. The proposed structure is designed to be applied to low-side current sensing method with low common mode input voltage. Using the low-side current measurement method has the advantage of reducing the burden on the circuit design. In addition, the ±30mV input voltage is resolved by the ADC with 15-bit resolution, eliminating the need for an additional programmable gain amplifier (PGA). The proposed a single-bit 2nd-order delta-sigma modulator has been implemented in a 350-nm CMOS process. It achieves 95.46-dB signal-to-noise-and-distortion ratio (SNDR), 96.01-dB spurious-free dynamic range (SFDR), and 15.56-bit effective-number-of-bits (ENOB) with an oversampling ratio (OSR) of 400 for 5-kHz bandwidth. The area and power consumption of the delta-sigma modulator are 670×490 ㎛2 and 414 ㎼, respectively.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.6
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• pp.59-76
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• 2019

Most technology-based entrepreneurship(TBE) go through an process of decline or disappear without overcoming the valley of death(VoD). The purpose of this study is to identify the growth dimension of TBE and to test the influence of firms activities on firms growth over time. This study identified the two-dimensional growth dimension divided by size and profit through exploratory factor analysis(EFA) of a number of growth indicators. Then, we defined the discrete state of growth firm in four states, divided by size and profit, and five states, including the closure of business. Multi-nomial logit model is used to predict the effect of TBE activities on a discrete state of growth firm(size×profit, closure of business) based on multiple independent variables. The independent variables are based on five representative firms activities: employment, marketing, R&D, financial activities, and general management activities. The growth stage of TBE over time has been categorized into three stages: early stage, middle stage, and late stage of business, taking into account the main periods during which the survival rate of startups sharply decreases. The analytical data of this study was based on the secondary data of the start-up supporting companies of government and public institutions. The subjects of analysis were TBE within 10 years. As a result of the empirical analysis, the employment and marketing activities of TBE show that early and mid-term activities had an effect on the state of firms growth. However, if there is a difference, employment activities have both positive and negative effects, while marketing activities have only a positive effect on size and profit growth. And besides, R&D activities, financial activities, and general management activities throughout the entire process of firms growth were found to be firms activities that have both positive and negative effects on firms growth. In addition, the age of the founder, the firms' industry, and the geographic location of the firms, which are general characteristics of the company, were found to have a distinctive effect on the growth status of the firms according to the growth stage.

• Journal of Cadastre & Land InformatiX
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• v.46 no.2
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• pp.27-42
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• 2016

Forest accounts for almost 64 percents of total land cover in South Korea. For inventorying, monitoring, and managing such large area of forest, application of remote sensing and geographic information system (RS/GIS) technology is essential. On the basis of spectral characteristics of satellite imagery, forest cover and tree species can be classified, and forest cover map can be prepared. Using three dimensional data of LiDAR(Light Detection and Ranging), tree location and tree height can be measured, and biomass and carbon stocks can be also estimated. In addition, many indices can be extracted using reflection characteristics of land cover. For example, the level of vegetation vitality and forest degradation can be analyzed with VI (vegetation Index) and TGSI (Top Grain Soil Index), respectively. Also, pine wilt disease and o ak w ilt d isease c an b e e arly detected and controled through understanding of change in vegetation indices. RS and GIS take an important role in assessing carbon storage in climate change related projects such as A/R CDM, REDD+ as well. In the field of climate change adaptation, impact and vulnerability can be spatio-temporally assessed for national and local level with the help of spatio-temporal data of GIS. Forest growth, tree mortality, land slide, forest fire can be spatio-temporally estimated using the models in which spatio-temporal data of GIS are added as influence variables.

• Journal of KIISE:Information Networking
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• v.30 no.4
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• pp.559-571
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• 2003

ENUM(tElephon NUmbering Mapping) is protocol that brings convergence between PSTN Networks and IP Networks using a unique worldwide E.164 telephone number as an identifier between different communication infrastructure. The mechanism provides a bridge between two completely different environments with E.164 number; IP based application services used in PSTN networks, and PSTN based application services used in IP networks. We propose a new way to organize and handle ENUM Tier 2 name servers to improve performance at the name resolution process in ENUM based application service. We build an ENUM based network model when NAPTR(Naming Authority PoinTeR) resource record is registered and managed by area code at the initial registration step. ENUM promises convenience and flexibility to both PSTN and IP users, yet there is no evidence how much patience is required when users decide to use ENUM instead of non-ENUM based applications. We have estimated ENUM response time, and proved how to improve performance up to 3 times when resources are managed by the proposed mechanism. The proposition of this thesis favorably influences users and helps to establish the policy for Tier 2 name server management.

• Journal of the Korean Society for information Management
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• v.36 no.4
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• pp.227-251
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• 2019

In early 2019, Korea passed the law that introduced data management plan policy similar to those adopted by national funding agencies in other countries. In anticipation of developing research data infrastructure and support services, this study analyzed Australia's relevant policies and policy instruments. A number of face-to-face interviews with the experts at the national funding agency, a national research data agency and a number of research libraries, along with focused literature analysis. In Australia, the 2015 Public Data Policy is applied to research data from publicly funded research. Research data management and sharing is recommended but not required by the national funding agency it its policy documents. Australian National Data Service(ANDS), Australia's national research data agency, is an important component of the national research infrastructure. ANDS plays a wide range of roles including research data platform development, education and training, policy support, and funding agency for small-scale R&D. Some of the Australian research libraries have developed in-house systems for research data storage and publishing. However, there is no significant demand for research data service as yet. Lessons learned include the following: ensuring transparency and predictability of research data policies, establishing a dedicated agency responsible for research data platform development and training, and cultivating data capabilities at research libraries.

• Journal of the Korea Society of Computer and Information
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• v.16 no.10
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• pp.147-153
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• 2011

In this paper, we present a new video management technique using forward timeline to efficiently store and delete the videos on a local server. The proposed method is based on capturing the changing preference of the videos according to recentness, frequency, and playback length of the requested videos. For this purpose, we utilize the forward timeline which represents the time area within a number of predefined intervals. The local server periodically measures time popularity and request segment of all videos. Based on the measured data, time popularity and request segment, the local server calculates the mean time popularity and mean request segment of a video using forward timeline. Using mean time popularity and mean request segment of video, we estimate the ranking and allocated storage space of a video. The ranking represents the priority of deletion when the storage area of local server is running out of space and the allocated storage space means the maximum size of storage space to be allocated to a video. In addition, we propose an efficient storage space partitioning technique in order to stably store videos and present a time based free-up storage space technique using the expected variation of video data in order for avoiding the overflow on a local server in advance. The simulation results show that the proposed method performs better than other methods in terms of hit rate and number of deletion. Therefore, our video management technique for local server provides the lowest user start-up latency and the highest bandwidth saving significantly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.382-390
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• 2018

This study developed a model to evaluate the quality management system of a medical device manufacturing company, and applied it to medical device manufacturers to understand the impact on business performance in response to international regulations and industry's change. This study prepared preliminary items, defined four (4) major factors (Plan-Do-Check-Act) that consist of the evaluation layers and items per category according to prior research review and expert interview, and calculated the weight and importance using AHP. The study results showed that responsibility & authority and quality objective in Planning Category, product-related requirement and R&D in Doing Category, Measuring and monitoring in Check Category, and review of meeting Regulatory and regulation in Action Category are relatively more important factors. The evaluation model developed based on the calculated weight and importance to business performance was applied to medical device manufacturers to investigate and analyze the implementation level of QMS and its impact on business performance according to each category. Most medical device manufacturers to be studied showed a reasonable level of QMS and effective business performance. Almost all the evaluation layers and items in the four (4) factors had a significant influence on business performance. Although the medical device quality management system is aimed mainly at license acquisition, it is important that management environment factors not related directly to licensing and authorization are important to business performance, and it is effective when these factors are integrated and operated within and outside the manufacturer.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.1
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• pp.111-118
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• 2019

For the security of a vast amount of information, it has been started to diagnose the site as a way of operating and managing the information owned by a company holding assets, to establish indexes to check the actual status and all kinds of standards to obtain security, and also to classify the information assets based on that. This has been extended to many different areas including policies to operate and manage information assets, services, the management of owned devices as physical assets, and also the management of logical assets for application software and platforms. Some of these information assets are already being operated in reality as new technology in new areas, for example, Internet of Things. Of course, a variety of electronic devices like Smart Home are being used in ordinary families, and unlike in the past, these devices generate a series of information life cycles such as accumulating and processing information. Moreover, as even distribution is now being realized, we are facing a task to secure the stability of information assets and also information that assets are holding. The purpose of this study is to suggest and apply standard security policy by moduling methods for information assets owned by companies and even families and obtain the enhancement of confidentiality as well as integrity.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.5
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• pp.482-492
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• 2019

The naval ship consists of a variety of classes, including patrol, frigate, destroyer and landing ship. There are various means of communication between combat ships belonging to the mobile fleet, including voice network, text message network and tactical data link. The operation at the existing mobile fleet level was conducted mainly on voice and text message, and tactical data link were used mainly to share tactical information between combat ships. This study intended to design HCI for commander like as KDDX of fleet level based on tactical data link, a means of communication between ships, to secure operational control of the mobile fleet. Recently, naval ships have been developed in the organization of various sensors, weapons and tactical data links integrated into the combat management system, and this study also designed the HCI based on the tactical data links integrated in the combat management system. The purpose of this study was to secure the operational efficiency of the tactical data link based on the combat management system in operation of the mobile fleet, and to improve the capability of the fleet commander to recognize the battlefield situation awareness.

• Resources Recycling
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• v.31 no.4
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• pp.3-11
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• 2022

Owing to the increasing demand for electric vehicles (EVs), appropriate management of their waste batteries is required urgently for scrapped vehicles or for addressing battery aging. With respect to technological developments, data-driven diagnosis of waste EV batteries and management technologies have drawn increasing attention. Moreover, robot-based automatic dismantling technologies, which are seemingly interesting, require industrial verifications and linkages with future battery-related database systems. Among these, it is critical to develop and disseminate various advanced battery diagnosis and assessment techniques to improve the efficiency and safety/environment of the recirculation of waste batteries. Incorporation of lithium-related chemical substances in the public pollutant release and transfer register (PRTR) database as well as in-depth risk assessment of gas emissions in waste EV battery combustion and their relevant fire safety are some of the necessary steps. Further research and development thus are needed for optimizing the lifecycle management of waste batteries from various aspects related to data-based diagnosis/classification/disassembly processes as well as reuse/recycling and final disposal. The idea here is that the data should contribute to clean design and manufacturing to reduce the environmental burden and facilitate reuse/recycling in future production of EV batteries. Such optimization should also consider the future technological and market trends.