• Journal of information and communication convergence engineering
• /
• v.16 no.2
• /
• pp.93-98
• /
• 2018

The Internet of Things (IoT) is a form of the emerging 4th industry in the 5G era. IoT is expected to develop naturally in our daily life in the 5G era in which high-speed communication will be completed. Along with the rise of IoT, concerns about security and malicious attacks are also increasing. This paper examines DoS attacks, which are one of the representative security threats of IoT and proposes a local detection and blocking system that are suitable for response to such attacks. First, systems of the LoRaWAN type, which are most actively researched in the IoT system field and DoS attacks that can occur in such systems were examined. Then, the inverse order tree algorithm using regional characteristics was designed as a cluster analysis form. Finally, a system capable of defending denial-of-service attacks in the 5G IoT system using local detection and blocking with the Euclidean distance was designed.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2024.05a
• /
• pp.383-385
• /
• 2024

이동통신 분야 사실표준화 기구인 3GPP(3rd Generation Partnership Project)에서는 기존의 5G 이동통신 기술을 향상시키기 위한 5G-Advanced 연구를 시작했다. 5G 및 5G-Advanced 시대에 접어들면서 네트워크를 향상시키기 위한 다양한 요소기술들이 등장하였지만, 이러한 기술 변화에 비례하여 네트워크를 위협하는 공격 표면들이 증가할 것으로 예상된다. 점진적인 네트워크 보안 위협에 대응하기 위해 보안 기술은 에드온(Add-on) 형태로 개발되었지만, 이는 이동통신시스템에서 보안 기술의 신뢰성을 낮추고 네트워크에 대한 보안 품질을 보장하지 못한다. 따라서, 본 논문에서는 5G-Advanced에서 사용되는 N2/N3 인터페이스에서 발생가능한 DoS(Denial of Service) 공격에 대해 실험하고 분석한다. 분석 결과는 5G-Advanced 이동통신시스템의 공격 표면을 나타내고 보안 내재화의 필요성을 강조한다.

• Korean Journal of Food Science and Technology
• /
• v.31 no.6
• /
• pp.1415-1420
• /
• 1999

This study was carried out to obtain basic information for breeding materials on the improvement of waxy corn (Zea mays L.). The percents of palmitic, stearic, oleic, linoleic and unsaturated fatty acids in 310 $F_1's$ analyzed were $14.6\;{\pm}\;2.5%,\;2.5\;{\pm}\;1.0%,\;24.8\;{\pm}\;4.2%,\;55.6\;{\pm}\;5.4%\;and\;81.8\;{\pm}\;3.1%$, respectively. The mean value of antioxidative ability was $22.8\;{\pm}\;5.9%$. The average contents of tocopherols, phenolic compounds and carotenoids were $36.2\;{\pm}\;11.5\;{\mu}g/mL,\;120.3\;{\pm}\;27.7\;{\mu}g/mL\;and\;0.4\;{\pm}\;0.6\;{\mu}g/mL$, respectively. The level of oleic acid was significantly correlated with the level of linoleic acid. The electron donating ability was significantly correlated with the level of phenolic compounds and tocopherols but not with the content of carotenoids

• Korean Journal of Food Science and Technology
• /
• v.31 no.3
• /
• pp.581-585
• /
• 1999

The antioxidative activity measured by electron donating ability was investigated for the breeding of the highest antioxidative waxy corn (Zea mays L.) and the research for the most effective antioxidant in waxy corn. The electron donating ability was $15.5{\sim}65.0%$. The contents of phenolic compounds and tocopherols and the absorbance at 450 nm were $102.3{\sim}323.5\;{\mu}g/mL$, $15.6{\sim}144.2\;{\mu}g/mL$ and $0.047{\sim}0.206$, respectively. The mean values of electron donating ability and contents of phenolic compounds and tocopherols of four black waxy corn were comparatively high, that is, 48.7%, $267.0\;{\mu}g/mL$ and $87.0\;{\mu}g/mL$, respectively. The electron donating ability was significantly correlated with the level of phenolic compounds and tocopherols but not with the content of carotenoids.

• KSBB Journal
• /
• v.14 no.3
• /
• pp.284-290
• /
• 1999

Glucose fed-batch culture was studied to improve cellulose productivity by Acetobacter xylinum BRC5. When initial glucose concentrations in batch cultures were less than 20 g/L, yield coefficients of cellulose (Yp/s) remained a constant value of 0.21 g cellulose/g glucose. But a low yield coefficient, Yp/s=0.13 was obtained from an initial glucose concentration of 40 g/L. Since initial high glucose concentrations in batch culture resulted in low yields of cellulose, constant fed-batch cultures were carried out. The optimal feed rate for fed-batch culture was 2.22 g glucose/L.h. In constant fed-batch culture without DO control, 10 g/L of cellulose was obtained from 40 g/L of glucose with this feed rate, which was approximately two fold higher than that of the batch culture with the same initial glucose concentration. In DO stat plus fed-batch culture, the highest cellulose productivity could be obtained when dissolved oxygen level was controlled at 10% of air saturation, and cellulose productivity increased about 1.5 times compared with that of the culture without DO control.

• Journal of Multimedia Information System
• /
• v.5 no.2
• /
• pp.131-138
• /
• 2018

This work describes a binary image based fast Difference of Gaussian (DoG) filter using zero-dimensional (0-d) convolution and state machine look up tables (LUTs) for image and video stitching hardware platforms. The proposed approach for using binary images to obtain DoG filtering can significantly reduce the data size compared to conventional gray scale based DoG filters, yet binary images still preserve the key features of the image such as contours, edges, and corners. Furthermore, the binary image based DoG filtering can be realized with zero-dimensional convolution and state machine LUTs which eliminates the major portion of the adder and multiplier blocks that are generally used in conventional DoG filter hardware engines. This enables fast computation time along with the data size reduction which can lead to compact and low power image and video stitching hardware blocks. The proposed DoG filter using binary images has been implemented with a FPGA (Altera DE2-115), and the results have been verified.

• Journal of Mushroom
• /
• v.20 no.2
• /
• pp.61-68
• /
• 2022

We investigated the standard cultivation substrate for Sparassis latifolia "Neowul" bred in Jeollabuk-do Agricultural Research and Extension Services. Cultivation characteristics and yield were assessed by varying the kind of sawdust and additives, and the mixing ratio. The cultivation period in larch sawdust was the shortest at 97 days. The yield was excellent (143.6 g). The findings indicated that larch is a tree species appropriate for the cultivation of S. latifolia. When the additives were varied, the yield and productivity (53.1%) were highest (116.6 g) for the wheat bran treatment. Thus, wheat bran would be an additive appropriate for culturing S. latifolia. Concerning the use of different mixing ratios, larch sawdust:beet-pulp:wheat bran ratios of 80:15:5 and 85:10:5 resulted in yields of 114.4 g and 111.4 g, and productivity of 52.5% and 51.8%, respectively. These yield and productivity values were not statistically different. Thus, the standard cultivation substrate for S. latifolia can comprise larch sawdust, beet pulp, and wheat bran at a ratio of 80:15:5 or 85:10:5. The carbon/nitrogen (C/N) ratio assumed to be appropriate for the cultivation of S. latifolia was 184-223. Pinheading would be difficult below a C/N substrate ratio of 105. Thus, the C/N ratio of the media, as well as the pH, would be vital factors affecting pinheading during S. latifolia cultivation.

• Korean Journal of Agricultural Science
• /
• v.38 no.1
• /
• pp.17-23
• /
• 2011

This research was conducted to investigate the influence of application rate of liming fertilizers on changes in soil chemical properties and growth of 'Red Madness' petunia in plug production. To achieve this, dolomite (DO) with 0, 1.0, 3.5, 8.0 or 13.0 $g{\cdot}L^{-1}$ and calcium carbonate (CC) with 0, 2.0, 2.5, 3.0, 3.5, or 4.0 $g{\cdot}L^{-1}$ were incorporated into peatmoss + vermiculite (1:1, v/v) during the root substrates formulation. The treatments of 3.5 $g{\cdot}L^{-1}$ of DO and 2.5 or 3.0 $gL^{-1}$ of CC had acceptable ranges of pH and EC in soil solution such as 5.6~6.2 and 0.7~1.0 $dS{\cdot}m^{-1}$, respectively. The faster rising of pH was observed in root media containing CC rather than those of DO. This indicates that the solubility of CC is higher than DO. The soil Ca concentrations in all treatments of CC were 1.8 times as high as those of DO. The treatments of 3.5 or 8.0 $g{\cdot}L^{-1}$ of DO had the highest soil Mg concentrations, but all treatments of CC had lower soil Mg concentrations than control treatment indicating that additional application of Mg fertilizers are required. The elevated application rate of DO or CC resulted in the increase of fresh and dry weight. But plant heights were not influenced by application of liming fertilizers. The results of tissue analysis showed that application of DO or CC influenced the $PO_4{^-}P$, Ca and Mg contents, but not influenced the contents of other nutrients such as N, P, Fe, Mn, Zn and Cu.

• Journal of Bio-Environment Control
• /
• v.21 no.4
• /
• pp.348-353
• /
• 2012

This study was conducted to figure out the possibility of non-drainage in muskmelon (Cucumis melo L.) hydroponics culture. Plants were grown under 3 different levels of drainage, standard (20~40%, SD), minimum (5~10%, MD), and non-drainage (ND). Throughout cultivation periods, constant water content and electrolyte conductivity changes in root zone were observed in SD in the range of 60~70% and $1.5{\sim}2.5dS{\cdot}m^{-1}$, respectively. ND treatment caused the fluctuation in water content and electrolyte conductivity of root zone and its change ranges were 30~50% in water content and $2{\sim}6dS{\cdot}m^{-1}$ in electrolyte conductivity, but ND treatment did not decrease fruit quality. Even if fruit fresh weight was slightly lower in ND with 1,863 g, than in SD with 1,990 g, the fruit weight in ND meets standard market size, 1,800~2,000 g. Higher soluble solids content was observed in fruit in ND than in SD and MD. Total amount of drainage per plant was 27,718, 15,769 and 2,346 mL in SD, MD and ND, respectively. SD showed $83.2m^3$ drainage, 34.5% drainage of irrigation amount whereas required total irrigation amount in ND was very low with $7m^3$.

• Journal of Animal Science and Technology
• /
• v.44 no.3
• /
• pp.297-304
• /
• 2002

This study was conducted to investigate the influence of dietary Panax Ginseng Refuse(PGR), Dioscorea Japonica Refuse(DJR) and Oriental Medicine Refuse(OMR) on performance(feed intake, body weight gain, feed conversion, mortality) of Korean Native Chicken(KNC). KNC were randomly assigned to one of the 4 dietary treatment : 1) control(commercial feed), 2) PGR(commercial feed supplemented with 5% panax ginseng leaves) 3) DJR(commercial feed with 5% dioscorea japonica hulls and 4) OMR (commercial feed with 5% oriental medicine refuse). 160 KNC were fed one of the above experimental diet for 12 weeks and slaughtered at 20 weeks of age. Daily DM intake of control, PGR, DJR and OMR diet were 125.79g, 122.26g, 122.30g and 123.72g, respectively, with no significantly difference(p$>$0.05). The DM utilizability of control and DJR(62.89% and 61.20%) diets were higher(p$<$0.05) than those of PGR and OMR(55.44% and 59.76%)(p$<$0.05). 16 weeks weight of bird fed control, PGR, DJR and OMR diets were 1,436.6g, 1,427.2g, 1,546g and 1,422.0g respectively with DJR being the highest than other treatments(p$<$0.05). Total feed intake of control, PGR, DJR and OMR diets were 6,087g, 5,947g, 5,816g and 5,852g, respectively where control was higher than other treatments. The feed conversion of PGR, DJR and OMR were higher than the control. Chicken housed mortality of control, PGR, DJR and OMR were respectively 24, 15, 13 and 20 birds with rather lower mortality in the supplented groups(p$<$0.05). The body weight, carcass weight and carcass yield were not different among the treatments. But abdominal fat of chicken in control and OMR groups were higher than that of DJR and PGR groups.