• Journal of Computing Science and Engineering
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• v.11 no.4
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• pp.152-159
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• 2017

Three-dimensional (3D) printing is applied to many areas of life, but 3D printing models are stolen by pirates and distributed without any permission from the original providers. Moreover, some special models and anti-weapon models in 3D printing must be secured from the unauthorized user. Therefore, 3D printing models must be encrypted before being stored and transmitted to ensure access and to prevent illegal copying. This paper presents a selective encryption algorithm for 3D printing models based on clustering and the frequency domain of discrete cosine transform. All facets are extracted from 3D printing model, divided into groups by the clustering algorithm, and all vertices of facets in each group are transformed to the frequency domain of a discrete cosine transform. The proposed algorithm is based on encrypting the selected coefficients in the frequency domain of discrete cosine transform to generate the encrypted 3D printing model. Experimental results verified that the proposed algorithm is very effective for 3D printing models. The entire 3D printing model is altered after the encryption process. The decrypting error is approximated to be zero. The proposed algorithm provides a better method and more security than previous methods.

• Journal of the Korean Applied Science and Technology
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• v.21 no.3
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• pp.252-258
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• 2004

This study was performed to evaluate characteristic of acid mine drainages (AMD) from abandoned mines in Kangwon-Do. Youngdong abandoned mine, and Soo and Hambaek abandoned mines in Hamtae were selected for this study. Average pHs of the mine drainages were 3-6.5, and those of Youngdong and Hambaek drainages were very acidic as 3-4. $SO_4^{-2}$ of Youngdong and Hambaek drainages were over 1,600 mg/L, which higher than average value (845 mg/L) of acid mine drainages in nationwide. Cu, Mn, and As concentrations of the drainages were lower than ‘Pollutant Discharge Permission'. Fe concentrations of Youngdong and Hambaek drainages were approximately 96 mg/L, which were two times higher than average value in nationwide. From correlation analysis using SPSS, significant correlation was not discovered between 'contaminants' analyzed in three acid mine drainages.

• The Journal of Industrial Distribution & Business
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• v.11 no.7
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• pp.7-17
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• 2020

Purpose: The purpose of this study was to identify factors that enhance the effectiveness of bulk text message advertising on consumer attention in the telecommunications industry in Zimbabwe. Research design, data and methodology: The study collected data using structured questionnaires. The study attracted 293 responses from consumer subscribers of the Zimbabwean telecommunications industry. Data was analysed using SPSS and measures of association, direction, strength and significance were used. Results: The study found out that the examined variables of bulk text messaging (Simplicity, Frequency and Informativeness) had a positive significant impact on consumers' attention (β= 0.645; p-value < 0.05). The study examined four bulk text advertising determinants, namely frequency, simplicity, informativeness and credibility. Only credibility was found to be statistically insignificant (p-value > 0.05), whilst frequency had an inverse effect on consumer attention. Simplicity of bulk text advertisements recorded a high positive and significant impact whilst informativeness was also positively, and significantly affecting consumer attention. Conclusions: The study concluded that for bulk text advertising to be effective, text messages should be informative, easy to understand and dispatched less frequently. It was further concluded that bulk text advertising should follow permission marketing where consumers consent before hand to be recipients of commercials.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.10
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• pp.1-8
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• 2013

Wireless Visible Light Communication is the technology that enables communication using LED illumination Infrastructure instead of existing illumination such as incandescent lamp or fluorescent light. Because VLC uses light for communication, it has no problem of frequency permission and is harmless to human body. It is also possible to check the communication through eye. So VLC can be used as a supplement to the Radio Frequency communication, Infrared in indoor environment. So far, researchers on the LED Visible light communication have focused on the increasing transmission speed, transmission distance, modulation method. However, there is few research of main factors that influence on system performance. System performance has been mainly predicted through simulation. In this paper, I recognized that these factors such as outside light noise, obstacle, LED panel position or emitted angle have a great impact on wireless communication system. So I experimented VLC system by changing distance and position to discover location suitable for BER regulation.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.281-293
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• 2018

As the public interest in environmental issues increased, the "Act On The Integrated Control Of Pollutant-Discharging Facility" was enacted. Through the integrated environmental pollution prevention act in which 19 industries with large environmental impacts are sequentially applied, pollutants can be managed in a medium-integrated manner and integrated permission of the business unit is possible and BAT can be applied to enable a scientific and proactive environmental management system. This study analyzed the overview of BAT reference documents(BREF), BAT setting procedure and method, and then suggested the development direction BAT and BAT-AEL monitoring method of a Electricity and Steam production facility.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.8A
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• pp.743-751
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• 2010

OFDMA femtocell becomes an effective solution to support indoor high data rate services instead of the macrocell systems. Although the advantage of the femtocell, the co-channel interference between the femocell and the macrocell is the most significant problem that reduces the system performance. Macrocell users who have no permission to access the femtocell suffer from interference of the downlink transmission of femtocell. Therefore, the femtocell should use transmission power as small as possible to reduce interference to macrocell users. In this paper, we define the margin adaptive power allocation problem for the femtocell and propose a heuristic power allocation algorithm to solve the problem. Simulation results show the performance of the proposed algorithm.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.9
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• pp.936-943
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• 2003

The miniaturized wireless endoscope consists of CMOS Image sensor, FPGA, LED, Battery, DC to DC Converter, Antenna and Transmitter. FSK transmitter is designed and fabricated with 10 mm(diameter)${\times}$23 mm(thickness) dimension considering the maximum permission exposure(MPE), system size, power consumption, linearity and modulation method. Experimental results is - 3.67 dBm output power level, 20 MHz frequency deviation, and - 99 dBc/Hz(@100 kHz offset) phase noise at 1.2 GHz. From the in-vivo experiment, the designed FSK transmitter has a acceptable capability for wireless endoscope.

• Journal of Acupuncture Research
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• v.32 no.4
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• pp.1-9
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• 2015

Objectives : The aim of this study is to develop the official Korean translation of the CARE guidelines. Methods : CARE guidelines were developed in 2013 though a consensus of experts led by the CARE group. It is the first reporting guideline for case reports that includes a 13-item checklist. We contacted the main author of the original manuscript and obtained permission to develop the Korean translation. The translation process followed a systematic protocol designated by the CARE group which included an independent back translation and confirmation from the original author. Results : The Korean translation of the CARE guidelines was completed with approval from the original author. The Korean checklist is posted on the official website (www.care-statement.org) and the final translation of the manuscript is introduced in this article as an appendix. Conclusions : We hope that this will help introduce the CARE guidelines to Korean authors and other stakeholders, induce a more active use of reporting guidelines, and eventually contribute to the overall improvement of the reporting quality of case reports published in Korean literature.

• Journal of Korean Academy of Nursing
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• v.27 no.3
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• pp.477-488
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• 1997

The purpose of this study was to understand the subjective breastfeeding experience of primiparous women to identify how breastfeeding was started and to explore the process of breastfeeding. The Grounded theory methodology was used. Data was collected from 6 primiparous women who had breastfed their infants for at least over 8weeks, recently breastfeeding or having breatfed their infants within the last 6 months. With the permission of the subjects, the interviews were recorded and transcribed. The data were analysed in the framework of grounded theory method as mapped out by Strauss and Corbin(1990). 105 concepts and 21 subcategories were confirmed in the analysis. In the process of data analysis, "Identity as a mother" was found to be the core phenomenon. The 21 sub-categories were as follows : natural food, neighbour inducement, self purpose, good feeling, tenderness, breast pain, change of breast shape, physical discomfort, loss of physical energy, confirmation of maternal role, formation of affection feeling of adhesion, one body through coupling, tie, capacity, role performance, mental comfort, healthy mother, healthy infant, confidence of breast milk, feeling of satisfaction. The sub -categories were again grouped into 14 categories including infant nutritious food, formation of breastfeeding opportunity, feeling of satisfaction, injury of the breast, physical suffering, awareness of mothering, formation of maternal affection, connecting, coupling, acceptance, effort, emotional stability, mother and child health and feeling of achievement.hievement.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.7B
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• pp.438-447
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• 2007

In the Internet, an identity service must to obtain permission from a user to allow them to share data with requesting service. For that, the privacy policy, which reflects legal regulations and preferences made by the user, is needed. Also, the management interface that aids the user to make the privacy policy and the PDP system that makes admission control and policy decisions in response to a request from an entity wanting to access the personal information are needed. In this paper, the privacy controller system model handled under the internet Identity management system environment is proposed. The system has the easy interface of policy generation and the efficient policy decision process. The system applies and modifies to the XACML of OASIS group. We propose that the privacy policy is divided into the three policies, which are the user policy, the domain policy and the basic offering policy. To resolve the collision between the policies, we also propose the collision resolution policy.