• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.45 no.1
• /
• pp.64-70
• /
• 2008

The H.264 standard is widely used due to the high compression rate and quality. The deblocking filter of the H.264 standard improves the quality of images by eliminating blocking artifacts of pictures, and it requires a lot of computation. We propose a new hardware architecture for the deblocking filter with pipelined architecture, 1-D filters which support both horizontal and vertical filtering and efficient memory management. Four memory blocks are configured for the efficient storage and access of the current macroblock and adjacent referenced sub-macroblocks, and the pixel data from the motion compensation unit can be transferred without waiting during the computation cycles of the deblocking filter. The number of computation cycles and the hardware area are reduced using the proposed architecture, and the performance of the H.264 decoder is improved. We design the deblocking filter using Verilog-HDL and implement using an FPGA. The designed deblocking filter can be used for decoding HD quality images at 77 MHz.

• Journal of Korean Society of Archives and Records Management
• /
• v.1 no.1
• /
• pp.245-257
• /
• 2001

Recently, The government has been brought in the electronic document system. So, It's been increasing the job processing with the electronic approval and the distribution business. However because of the variety of the storage type of electronic document, it's expected many difficulties in the public-usage and etemity-preservation of the information later. also, There are several problems to manage electronic document system, for example, absence of the important function for managing records, etc. So, We propose the methodology as a way to solve several problems of managing electronic document in this paper. It grows the business which is produced in processing the electronic records management. The kind of document file produced by the government is various. Through introducing the standard format of document file, hereafter it has an effect on helpfulness in standardizing the electronic document system, and people recognize the situation of problem to append the important function of the preservation and usage for the electronic document system. The key task is to make the document system with keeping records and following functions according to the law of records management. As applying the standard electronic document system to manage records, the records of the processing section to the data center and then the records of the data center transfer to the government records and archives center. So, the records which be transferred can be preservative and available. The record, such as visual and auditory record which is not easy to digitalize, can be digitally preservative and available in the government records and archives center.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.39 no.2
• /
• pp.120-128
• /
• 2012

The purpose of this study was to evaluate the attitude and knowledge level of a group of elementary school teachers in management of traumatic dental injury. The sample consisted of 231 elementary school teachers in Jeon-Buk province, and data was collected by means of a self-administered questionnaire. The questionnaire surveyed the teachers'general information, attitude on the dental trauma education, knowledge of management of tooth fracture, luxation, avulsion and tooth storage media. Only 15.2% of the teachers had received dental first aid treatment education, but 97% were favorable to receiving education. Although there were differences among the questions, insufficient knowledge and awareness of the management of traumatic dental injury were shown in the majority of teachers. It is recommended that education strategies and programs for improving the awareness of immediate management of traumatic dental injuries are necessary for elementary school teachers in Jeon-Buk province.

• The KIPS Transactions:PartD
• /
• v.15D no.6
• /
• pp.755-766
• /
• 2008

Recently, NAND flash memory is becoming into the spotlight as a next-generation storage device because of its small size, fast speed, low power consumption, and etc. compared to the hard disk. However, due to the distinct characteristics such as erase-before-write architecture, asymmetric operation speed and unit, disk-based systems and applications may result in severe performance degradation when directly implementing them on NAND flash memory. Especially when a B-tree is implemented on NAND flash memory, intensive overwrite operations may be caused by record inserting, deleting, and reorganizing. These may result in severe performance degradation. Although ${\mu}$-tree has been proposed in order to overcome this problem, it suffers from frequent node split and rapid increment of its height. In this paper, we propose Log-Structured B-Tree(LSB-Tree) where the corresponding log node to a leaf node is allocated for update operation and then the modified data in the log node is stored at only one write operation. LSB-tree reduces additional write operations by deferring the change of parent nodes. Also, it reduces the write operation by switching a log node to a new leaf node when inserting the data sequentially by the key order. Finally, we show that LSB-tree yields a better performance on NAND flash memory by comparing it to ${\mu}$-tree through various experiments.

• Journal of Digital Convergence
• /
• v.15 no.4
• /
• pp.285-293
• /
• 2017

They are rapidly evolving malicious attacks on smart devices, and to timely protect the smart devices from these attacks has become a very important issue. In particular, smishing attack has emerged as one of the most important threats on the smartphone. In this paper, we propose the cloud service that can fundamentally protect the user from the risk of smishing attack. The proposed scheme provides cloud messaging service that can filter text messages including URLs in the user's smart device, view and manage them through a virtual machine provided by a cloud server. The existing techniques for preventing smshing attacks protect only malicious code of a known pattern and there is the possibility of error such as FP(False Positive) or FN(False Negative). However, since the proposed method automatically filters all text messages including URLs, storing, viewing, and managing them in their own storage space on the cloud server, it can completely block the installation of malwares(malicious codes) on the user's smart device through smishing attacks.

• Food Science and Preservation
• /
• v.17 no.6
• /
• pp.793-799
• /
• 2010

Kimchi was fermented in permeability-controlled polyethylene containers, in glazed onggi (Korean ethnic earthenware) or glass bottles at $5^{\circ}C$ for 8 weeks. During 4 weeks of storage, kimchi fermented in the permeability-controlled container showed a stable fermentation pattern, in terms of changes in pH and acidity, compared with kimchi fermented in the other containers. With respect to changes in bacterial counts, kimchi fermented in polyethylene containers showed vigorous multiplication of lactic acid bacteria, especially Lactobacillus sp., but slow growth of total aerobic bacteria. The springiness of kimchi fermented in the polyethylene containers was optimal (about 10% more than that of glass bottle-fermented kimchi), and the overall acceptability and hardness of container-fermented kimchi were excellent upon sensory evaluation. The DPPH radical-scavenging activity of kimchi fermented in polyethylene containers was also greater (91%) than that of kimchi fermented in glazed onggi (73%) or glass bottles (63%). The $O_2$ and $CO_2$ permeabilities of the polyethylene containers were higher (458 and $357\;mmol\;h^{-1}\;m^{-2}\;atm^{-1}$, respectively) than were those of the other containers; the permeability ratio was 0.8. Glass bottles showed no permeance. The results indicate that permeability-controlled polyethylene containers may be used for kimchi fermentation.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.10 no.3
• /
• pp.177-184
• /
• 2016

The purpose of this study was to investigate caretakers' demands and request in electric wheelchairs. The survey included the usability questionnaire (safety, operability, satisfactions) which were selected by opinions of caretakers and specialist of rehabilitation for electric wheelchairs. The survey also included questionnaires consisting of such questions as to demographic information, care experience, care time, and care burden, and demand for folding electric wheelchairs. Participants were fifty caretakers of electric wheelchair users. Caretakers' average age was 54.54years, and the average duration of their care experience was 80.98 months with average care time 9.80 hours per day. In safety and operability, most of participants were mostly satisfied. However, in satisfaction of weight and clean of electric wheelchairs was dissatisfied. They reported that the biggest problem of electric wheelchairs were too heav and difficult to control and that the greatest difficulty in helping electric wheelchair users was helping them with transfer to and from the wheelchair. They also need their prefer to develop folding electric wheelchairs. In this study, caretakers emphasized necessity of development light, easy to storage and clean electric wheelchairs. In conclusion, it is required to develop folding electric wheelchairs to reflect caretaker's opinions.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.16 no.3
• /
• pp.169-180
• /
• 2014

Chemical weathering of forest soils can reduce atmospheric $CO_2$ concentration over geologic time scales, providing many essential elements for life. Although many studies have been conducted on the effects of elevated atmospheric $CO_2$ on forest carbon storage using open top chambers and FACE (Free air $CO_2$ enrichment) facilities since the 1990s, studies on chemical weathering of forest soils under elevated $CO_2$ are relatively rare. Here I review on how elevated atmospheric $CO_2$ can affect the chemical weathering of forest soils and suggest directions on future research. Despite the recent advances in chemical weathering of forest soils under elevated atmospheric $CO_2$, it is still not clear how the large volume of forest soils would react under the condition. Future studies on weathering of forest soils covering large areas from the tropics to the polar regions with carefully monitored pre-treatment data would provide key information on how soils, the Earth's life sustaining engine, change under climate change.

• Journal of Korea Water Resources Association
• /
• v.53 no.11
• /
• pp.985-997
• /
• 2020

SWAT (Soil and Water Assessment Tool)-MODFLOW (Modular Groundwater Flow) is a coupled model that linking semi-distributed watershed hydrology with fully-distributed groundwater behavior. In this study, the groundwater simulation results of SWAT and SWAT-MODFLOW were compared for Bokhacheon watershed in Namhan river basin. The models were calibrated and validated with 9 years (2009~2017) daily streamflow (Q) data of Heungcheon (HC) water level gauge station and the daily groundwater level observation data of Yulheon (YH). For SWAT, the groundwater parameters of GW_DELAY, GWQMN, and ALPHA_BF affecting baseflow and recession phase were treated. The SWAT results showed the coefficient of determination (R²) of 0.7 and Nash-Sutcliffe model efficiencies (NES_Q, NSE_inQ) for Q and 1/Q with 0.73 and -0.1 respectively. For SWAT-MODFLOW, the spatio-temporal aquifer hydraulic conductivity (K, m/day), specific storage (S_s, 1/m), and specific yield (S_y) were applied. The SWAT-MODFLOW showed R², NSE_Q, and NSE_inQ of 0.69, 0.74, and 0.51 respectively. The SWAT-MODFLOW considerably enhanced the low flow simulation with the help of aquifer physical information. The total streamflow of SWAT and SWAT-MODFLOW were 718.6 mm and 854.9 mm occupying baseflow of 342.9 mm and 423.5 mm respectively.

• Journal of the Korean Institute of Gas
• /
• v.7 no.1 s.18
• /
• pp.1-9
• /
• 2003

A Multi-distinction Equipment Screening Algorithm (MESA) is proposed. It selectively integrates Dow's F&EI as its process hazard index technique and ESA (Equipment Screening Algorithm) as qualitative hazard classification technique, and retrieves a detailed list of hazardous equipments with the total hazard indices of those equipments. The inherent expert system, which includes the accident scenarios of the equipments and processes and experts' views of them, narrows further down the list of hazardous equipments and recommends only the most notable candidates. Through the case study of distinguishing the hazardous ranking of the equipments of the LPG underground storage process, using the expert system or not, the applicability of MESA has been validated. Taking the characteristics of the process equipments with hazardous ranking in the point of process intrinsic safety, this proposed algorithm would contribute to providing engineers or managers with information on constructing safely devices and mitigation devices and on scheduling emergency response planning.