• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.4
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• pp.49-58
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• 2014

A low-swing differential near-ground signaling (NGS) transceiver for low-power high-speed mobile I/O interface is presented. The proposed transmitter adopts an on-chip regulated programmable-swing voltage-mode driver and a pre-driver with asymmetric rising/falling time. The proposed receiver utilizes a new multiple gain-path differential amplifier with feed-forward capacitors that boost high-frequency gain. Also, the receiver incorporates a new adaptive bias generator to compensate the input common-mode variation due to the variable output swing of the transmitter and to minimize the current mismatch of the receiver's input stage amplifier. The use of the new simple and effective impedance matching techniques applied in the transmitter and receiver results in good signal integrity and high power efficiency. The proposed transceiver designed in a 65-nm CMOS technology achieves a data rate of 13 Gbps/channel and 0.3 pJ/bit (= 0.3 mW/Gbps) high power efficiency over a 10 cm FR4 printed circuit board.

• Journal of the Korea Society of Computer and Information
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• v.11 no.6 s.44
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• pp.175-184
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• 2006

Computer Forensics functions by defending the effects and extracting the evidence of the side effects for production at the court. Has the faultlessness of the digital evidence been compromised during the investigation, a critical evidence may be denied or not even be presented at the trial. The presented monograph will deliberate the faultlessness-establishing chain procedures in disk forensics, system forensics, network forensics, mobile forensics and database forensics. Once the faultlessness is established by the methods proposed, the products of investigation will be adopted as a leading evidence. Moreover, the issues and alternatives in the reality of digital investigation are presented along with the actual computer forensics cases, hopefully contributing to the advances in computer digital forensics and the field research of information security.

• Journal of Soil and Groundwater Environment
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• v.16 no.2
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• pp.61-76
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• 2011

This study was objected to provide suggestions for best management practices to restore the cultural and historical values of the wells in Palaces as well as their water qualities. Water resources in the five Palaces in Seoul Metropolitan, including Gyeongbokgung, Changdeokgung, Changgyeonggung, Jongmyo Shrine, and Deoksugung, were surveyed for their physical flows and chemical compositions from April to July in 2010. Ground waters in most wells were found at depths within 5 m from the ground surface, showing typical water-table aquifer systems. Hydraulic gradients indicate water resources in Gyeongbokgung, Changdeokgung, and Changgyeonggung flowing toward south, and toward east in Deoksugung area. Especially, water-level fluctuation data at S-10 in Deoksugung implied the influence of groundwater discharge facility. In Jongmyo Shrine, water was not detected in wells, indicating the water level was lower than the well depth. Based on the water chemistry and stable isotope analyses, water resources and their qualities appeared to be formed by the water-rock interaction along the groundwater paths. S-10 (Deoksugung) and S-14 (Changgyeonggung) samples were contaminated with nitrate ($NO_3$) in levels of higher than Korean drinking water standard, 10 mg/L as $NO_3$-N, but once in four sampling campaigns. In the situation that water resources in Palaces still maintain natural characteristics, the materials that will be used for the restoration and improvement of the Palace water supplies should be carefully selected not to disturb the natural integrity. In addition, because the wells are located in the center of metropolitan area, a systematic monitoring should be applied to detect and to manage the potential impacts of underground construction and various pollution sources.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.2
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• pp.170-178
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• 2010

In this paper, we propose the modeling of the power/ground plane which includes complex dielectric permittivity and loss tangent for the power/ground coupled noise. In order to estimate the effects of the dielectric substrate for the coupled noise, we used full-wave simulators, HFSS(High Frequency Structure Simulation) and MWS(MicroWave Studio). The simulated results for the commercial substrates are compared with the measured values. TLM(Transmission Line Method) was used for the calculation of power plane impedance using Debye model which depicts the dielectric loss of PCB. Finally, impedance from proposed circuit model showed very good coincidence to the measured data.

• International Journal of Oral Biology
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• v.35 no.1
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• pp.1-5
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• 2010

Human fibroblasts that maintain the structural integrity of connective tissues by secreting precursors of the extracellular matrix are typically cultured with serum. However, there are potential disadvantages of the use of serum including unnatural interactions between the cells and the potential for exposure to animal pathogens. To prevent the possible influence of serum on fibroblast cultures, we devised a serum-free growth method and present in vitro data that demonstrate its suitability for growing porcine fetal fibroblasts. These cells were grown under four different culture conditions: no serum (negative control), 10% fetal bovine serum (FBS, positive control), 10% knockout serum replacement (KSR) and 20% KSR in the medium. The proliferation rates and viabilities of the cells were investigated by counting the number of cells and trypan blue staining, respectively. The 10% FBS group showed the largest increase in the total number of cells ($1.09\;{\times}\;10^5\;cells/ml$). In terms of the rate of viable cells, the results from the KSR supplementation groups (20% KSR:64.7%; 10% KSR: 80.6%) were similar to those from the 10% FBS group (68.5%). Moreover, supplementation with either 10% ($3.0\;{\times}\;10^4\;cells/ml$) or 20% KSR ($4.8\;{\times}\;10^4\;cells/ml$) produced similar cell growth rates. In conclusion, although KSR supplementation produces a lower cell proliferation rate than FBS, this growth condition is more effective for obtaining an appropriate number of viable porcine fetal fibroblasts in culture. Using KSR in fibroblast culture medium is thus a viable alternative to FBS.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.9
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• pp.1573-1581
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• 2006

To utilize actively the agent which is one of the elements of revitalization of Agro-Foods Mobile I-commerce, an essential prerequisite is agent security. IF using partial PKI(Public Key Infrastructure)-based confirmation mechanism providing security for the agent, the size of agent is becoming larger, the result of the transmission speed is slow, and the confirmation speed is tardy as well because of performing calculation of public keys such as RSA and needing linkage with the CA for the valid examination of certificates. This paper suggests a mechanism that can cross certification and data encryption of each host in the side of improving the problems of key distribution on agent by shaping key chain relationship. This mechanism can guarantee the problem of ky distribution by using agent cipher key(ACK) module and generating random number to fit mobile surroundings and to keep the secret of the agent. Suggested mechanism is a thing that takes into consideration security and efficiency to secure agent for the revitalization of M-Commerce, and is a code skill to make the agent solid and is a safe mechanism minimizing the problems of memory overflow.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.25 no.2
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• pp.88-97
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• 2016

Aesthetics can be affected by the interest and the trend of the time. There are the limits of the equipment and materials required for the times, aesthetic case is also considered necessary to overcome them and will introduce the following case in accordance with the patients demands and circumstances. I hope the further development of CAD/CAM by taking over the things have done in the analogue by utilizing the latest technology that is thought to challenge the current limit itself is important. Digital has the advantages in various perspectives. Especially, I am very interested in as related to "digital communication." In particular, when utilizing the data using intra oral scanner can easily direct converse about prosthesis between the dentist and the dental technician through a software program Now, as the digital communication affects the integrity of the prosthesis directly, I had a expectation of a new era for the prosthetic and aesthetics. In this case report, I would like to introduce direct and real digital communication through the following 2 parts.

• Convergence Security Journal
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• v.16 no.5
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• pp.3-9
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• 2016

The wireless sensor networks have become an economically viable monitoring solution for a wide variety of civilian and military applications. The main challenge in wireless sensor networks is the secure transmission of information through the network, which ensures that the network is secure, energy-efficient and able to identify and prevent intrusions in a hostile or unattended environment. In that correspondence, this paper proposes a distributed clustering process that integrates the necessary measures for secure wireless sensors to ensure integrity, authenticity and confidentiality of the aggregated data. We use the notion of pre-distribution of symmetric and asymmetric keys for a secured key management scheme, and then describe the detailed scheme which each sensor node within its cluster makes use of the pre-distribution of cryptographic parameters before deployment. Finally, we present simulation results for the proposed scheme in wireless sensor network.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.3
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• pp.26-34
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• 1999

A new silicon-based IC interconnect transmission line parameter extraction methodology is presented and experimentally examined. Unlike the PCB or MCM interconnects, a dominant energy propagation mode in the silicon-based IC interconnects is not quasi-TEM but slow wave mode(SWM). The transmission line parameters are extracted taking the silicon substrate effect (i.e., slow wave mode) into account. The capacitances are calculated considering silicon substrate surface as a ground. Whereas the inductances are calculated by using an effective dielectric constant. In order to verify the proposed method, test patterns were designed. Experimental data have agreement within 10%. Further, crosstalk noise simulation shows excellent agreements with the measurements which are performed with high-speed time domain measurement ( i.e., TDR/TDT measurements) for test pattern, while RC model or RLC model without silicon substrate effect show about 20~25% underestimation error.

• The Korean Journal of Community Living Science
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• v.24 no.1
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• pp.71-84
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• 2013

In this study we examine the relationship between the social participation in the early adolescents and school adjustment as well as the mediating effects of a sense of community. Findings provide ways of intervention that can increase a youth's school life. Based on samples of 2,351 first grade middle school students from the data in the 'Korea Youth Panel Survey' administered by the National Youth Policy Institute, we analysed the correlation among the variables. The results are as follows. First, the social participation of youths showed a major influence on school adjustment, and was identified as: the more the students participate in social activities, the better the students get adjusted to school. Second, the social participation has a significant effect on sense of community. In other words, the more the students participate in social activities, the more the students get a sense of community. Third, a sense of community mediated the process of social participation on school adjustment. These findings indicate that in order to increase a youth's school adjustment, a promotion of social participation and an effort to increase a sense of community are required. The implications of these findings suggest that by intervening social welfare and policy, can improve the integrity of a youth's school life.