• Title/Summary/Keyword: Black Matrix

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System implementation for Qshing attack detection (큐싱(Qshing) 공격 탐지를 위한 시스템 구현)

  • Hyun Chang Shin;Ju Hyung Lee;Jong Min Kim
    • Convergence Security Journal
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    • v.23 no.1
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    • pp.55-61
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    • 2023
  • QR Code is a two-dimensional code in the form of a matrix that contains data in a square-shaped black-and-white grid pattern, and has recently been used in various fields. In particular, in order to prevent the spread of COVID-19, the usage increased rapidly by identifying the movement path in the form of a QR code that anyone can easily and conveniently use. As such, Qshing attacks and damages using QR codes are increasing in proportion to the usage of QR codes. Therefore, in this paper, a system was implemented to block movement to harmful sites and installation of malicious codes when scanning QR codes.

Assessment of Genetic Diversity and Relationships Between Korean Cattle and Other Cattle Breeds by Microsatellite loci (Microsatellite loci 분석에 의한 한우와 타 품종간의 유전적 유연관계)

  • Yoon, D.H.;Park, E.W.;Lee, S.H.;Lee, H.K.;Oh, S.J.;Cheong, I.C.;Hong, K.C.
    • Journal of Animal Science and Technology
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    • v.47 no.3
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    • pp.341-354
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    • 2005
  • For the genetic assessment of the cattle breeds including Hanwoo, eleven microsatellite markers on ten bovine autosomes were genetically characterized for 618 individuals of nineteen cattle breeds; North Eastern Asian breeds (Korean cattle, Korean Black cattle, Japanese Black cattle, Japanese Brown cattle, Yanbian cattle), Chinese yellow cattle (Luxi cattle, Nanyang cattle), European Bas taurus (Angus, Hereford, Charolais, Holstein, Limousin), African Bas taurus (N'Dama, Baoule), African Bas indicus (Kavirondo Zebu, White Fulani), Asian Bas indicus (Sahiwal, Nelore) and one Bali cattle, Bas banteng as an outbreed-reference population. Allele frequencies derived from the genotyping data were used in estimating heterozygosities, gene diversities and genetic distances. The microsatellite loci were highly polymorphic, with a total of 162 different alleles observed across all loci. Variability in allele numbers and frequencies was observed among the breeds. The average expected heterozygosity of North Eastern Asian breeds was higher than those of European and African taurines, but lower than those of Asian and African indicines. Genetic distances were estimated using Nei's DA genetic distance and the resultant DA matrix was used in the construction of the phylogenetic trees. The genetic distances between North Eastern Asian cattle breeds and Bas indicus were similar with those between European Bas taurus and Bas indicus, and African Bas taurus and Bas indicus, respectively. The clusters were clearly classified into North Eastern Asian, European and African taurines groups as well as different cluster with Chinese mainland breeds, firstly out-grouping with Bas indicus. These results suggest that Korean cattle, Hanwoo, had not been originated from a crossbred between Bas primigenius in Europe and Bas indicus in India and North Eastern Asian Bas taurus may be have separate domestication from European and African Bas taurus.

Comparative assessment of age, growth and food habit of the black-chinned tilapia, Sarotherodon melanotheron (Rüppell, 1852), from a closed and open lagoon, Ghana

  • Zuh, Cephas Kwesi;Abobi, Seth Mensah;Campion, Benjamin Betey
    • Fisheries and Aquatic Sciences
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    • v.22 no.12
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    • pp.31.1-31.12
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    • 2019
  • Background: The black-chinned tilapia, Sarotherodon melanotheron, is the most abundant fish species in the Nakwa (an open lagoon) and Brenu (a closed lagoon) in the Central Region of Ghana. Aspects of the life history characteristics and the ecology of the fish populations in both lagoons were studied to assess the bio-ecological status of this important resource. Methods: Fish samples were obtained from fishermen that fish on the Nakwa and Brenu lagoons using cast, drag and gill nets. The age of the fish was assessed from otoliths analysis and its growth modelled following the von Bertalanffy growth function. Morphometric characteristics of the fish populations were analysed using power regression and ANOVA for parameters comparisons, and Student's t test to determine whether species grew isometrically. The percentage occurrence method was used to analyse the stomach contents of the fish. Results: A total of 382 fish samples from both lagoons were measured, comprising 209 from Nakwa lagoon and 176 from Brenu lagoon. The size and weight of fish samples ranged between 3.9-11.5 cm total length and 1.0-27.3 g for Nakwa Lagoon and 5.6-12.8 cm total length and 3.2-29.8 g for the Brenu Lagoon. The estimated von Bertalanffy growth parameters were L∞ = 12.04 cm and K = 2.76/year for the Nakwa Lagoon samples and L∞ = 13.44 cm and K = 3.27/year for Brenu Lagoon samples. Daily otolith incremental rate ranged from 0.01-0.03 mm per day to 0.01-0.02 mm per day for Nakwa and Brenu lagoons, respectively. Stomach content analysis of the fish samples revealed that the species are planktivorous and the range of food varied between the lagoons. Green algae were the most prevalent food item in the stomachs of the fish samples from Nakwa with the frequency of 69% whilst diatoms (80.5%) were most prevalent phytoplanktonic food item for the fish in Brenu lagoon. Conclusions: The estimates of asymptotic length for the species in both lagoons are close to known values of the species length at first sexual maturity and points to intensive fishing pressure. As a consequence, a comprehensive sample-based survey is required in both lagoons to derive estimates of management reference points. The results of the stomach content analysis are beneficial to the construction of diet matrix for ecosystem models of the two systems.

Mechanical, Thermal and Electrical Properties of Polymer Nanocomposites Reinforced with Multiwalled Carbon Nanotubes (다중벽 카본나노튜브가 보강된 고분자 나노복합체의 기계적, 열적, 전기적 특성)

  • Kook, Jeong-Ho;Huh, Mong-Young;Yang, Hoon;Shin, Dong-Hoon;Park, Dae-Hee;Nah, Chang-Woon
    • Polymer(Korea)
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    • v.31 no.5
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    • pp.422-427
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    • 2007
  • Semiconducting layers are thin rubber film between electrical cable wire and insulating polymer layers having a volume resistivity of ${\sim}10^2{\Omega}cm$. Commercial semiconducting layers ire composed of polymer composites reinforced with more than 30 wt% of carbon blacks. A new semiconducting material was suggested in this study based on the carbon nanotube(CNT)-reinforced polymer nanocomposites. CNT-reinforced polymer nanocomposites were prepared by solution mixing and precipitation with various polymer type and dual filler system. The mechanical, thermal and electrical properties were investigated as a function of polymer type and dual filler system based on CNT and carbon black. The volume resistivity of composites was strongly related with the crystallinity of polymer matrix. With the decreased crystallinity, the volume resistivity decreased linearly until a critical point, and it remained constant with further decreasing the crystallinity. Dual filler system also affected the volume resistivity. The CNT-reinforced nanocomposite showed the lowest volume resistivity. When a small amount of carbon black(CB) was replaced the CNT, the crystallinity increased considerably leading to a higher volume resistivity.

Syntaxonomy and Synecology of the Robinia pseudoacacia Forests (아까시나무림의 군락분류와 군락생태)

  • Cho, Kwang-Jin;Kim, Jong-Won
    • The Korean Journal of Ecology
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    • v.28 no.1
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    • pp.15-23
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    • 2005
  • The black locust (Robinia pseudoacacia L.) forests were studied by a phytosociological approach. Particular attention was given to characterize the vegetation classification, distribution pattern, and ecological flora of the syntaxa classified. A total of 38 releves were analyzed by using Correlation coefficient, UPGMA as the clustering method, and Principal Coordinates Analysis for ordination. Ecological flora analyzed by plant character sets such as scrambler, annual and biennial plants, forest elements, and actual urbanization index. The analyzed data are based on site-releve matrix with relative net contribution degree (r-NCD) of species. A total of 77 families, 193 genera and 323 species of vascular plants are recorded. Camellino-Robinietum pseudoacaciae ass. nov. and Phragmites-Robinia pseudoacacia community were described. Main cluster and ordination could be separated: 1) urban type, 2) rural type, 3) riparian type, and 4) combined type. It is defined that the Robinietum is a representative unit on the black locust afforestation, Phragmites-Robinia community on the lentic zone in the river ecosystem, and Cameliino-Robinietum ailanthetosum altissimae as an urban forest type. The Robinietum was considered as a perpetual community.

A Comparison Study on Reinforcement Behaviors of Functional Fillers in Nitrile Rubber Composites

  • Seong, Yoonjae;Lee, Harim;Kim, Seonhong;Yun, Chang Hyun;Park, Changsin;Nah, Changwoon;Lee, Gi-Bbeum
    • Elastomers and Composites
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    • v.55 no.4
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    • pp.306-313
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    • 2020
  • To investigate the reinforcing effects of functional fillers in nitrile rubber (NBR) materials, high-structure carbon black (HS45), coated calcium carbonate (C-CaCO3), silica (200MP), and multi-walled carbon nanotubes (MWCNTs) were used as functional filler, and carbon black (SRF) as a common filler were used for oil-resistant rubber. The curing and mechanical properties of HS45-, 200MP-, and MWCNT-filled NBR compounds were improved compared to those of the SRF-filled NBR compound. The reinforcing effect also increased with a decrease in the particle size of the fillers. The C-CaCO3-filled NBR compound exhibited no reinforcing effect with increasing filler concentration because of their large primary particle size (2 ㎛). The reinforcing behavior based on 100% modulus of the functional filler based NBR compounds was compared by using several predictive equation models. The reinforcing behavior of the C-CaCO3-filled NBR compound was in accordance with the Smallwood-Einstein equation whereas the 200MP- and MWCNT-filled NBR compounds fitted well with the modified Guth-Gold (m-Guth-Gold) equation. The SRF- and HS45-filled NBR compounds exhibited reinforcing behavior in accordance with the Guth-Gold and m-Guth-Gold equations, respectively, at a low filler content. However, the values of reinforcement parameter (100Mf/100Mu) of the SRF- and HS45-filled NBR compounds were higher than those determined by the predictive equation model at a high filler content. Because the chains of SRF composed of spherical filler particles are similarly changed to rod-like filler particles embedded in a rubber matrix and the reinforcement parameter rapidly increased with a high content of HS45, the higher-structured filler. The reinforcing effectiveness of the functional fillers was numerically evaluated on the basis of the effectiveness index (��SRF/��f) determined by the ratio of the volume fraction of the functional filler (��f) to that of the SRF filler (��SRF) at three unit of reinforcing parameter (100Mf/100Mu). On the basis of their effectiveness index, MWCNT-, 200MP-, and HS45-filled compounds showed higher reinforcing effectiveness of 420%, 70%, and 20% than that of SRF-filled compound, respectively whereas C-CaCO3-filled compound exhibited lower reinforcing effectiveness of -50% than that of SRF-filled compound.

Perianal Adenocarcinoma in Dog (개에서의 항문주위선 샘암종)

  • Yang, Hai-Jie;Do, Sun-Hee;Yuan, Dong-Wei;Hong, Il-Hwa;Ki, Mi-Ran;Park, Jin-Kyu;Goo, Moon-Jung;Lee, Hye-Rim;Hwang, Ok-Kyung;Han, Jung-Youn;Hong, Kyung-Sook;Park, Ho-Yong;Yoo, Sung-Eun;Jeong, Kyu-Shik
    • Journal of Life Science
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    • v.18 no.2
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    • pp.279-283
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    • 2008
  • A 12.6-year-old, male Shitzu was diagnosed with perianal adenocarcinoma. The presented mass was brown to black, $4{\times}3{\times}3cm$ in size, and yellowish on cut section. Microscopic findings revealed that the mass composed of variable sized clusters of hepatoid cells with inconspicuous distinct. The tumor cells were polyhedral and pyknotic and exhibited high mitotic activity. Tumor cells intermingled with basaloid cells and primitive cells invaded the adjacent normal tissues. Basaloid cells exhibited positive immunoreactivity for Epidermal growth factor receptor (EGFR), human epidermal growth factor receptor (HER-2/neu), matrix metallopnateinase 9 (MMP-9), and perianal adenocarcinoma, protein kinase C alpha (PKC ${\alpha}$). Generally, tumors of the perianal gland are common and benign 4.5 times more often than carcinoma in the dog, particularly in males. In the present report, we examined histopathological and immunohistochemical characteristics of a rare perianal adenocarcinoma in association with proteins involved tumor metastasis and adenocarcinoma development.

An Experimental Study for Electro-active Polymer Electrode and Actuator (전기활성 고분자 전극 및 구동기에 관한 실험적 연구)

  • Lee, Jun-Man;Ryu, Sang-Ryeoul;Lee, Dong-Joo;Lin, Zheng-Jie
    • Composites Research
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    • v.26 no.5
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    • pp.289-294
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    • 2013
  • A thinner is used to improve the multi-walled carbon nano-tube (CNT) and carbon black (CB) dispersion in a polymer matrix and to make a soft electrode. The electrical and mechanical properties of the soft electrodes are investigated as functions of CNT, CB and thinner content. The optimal mixing condition for the electrode is thinner 80, CNT 3.5, CB 18 (phr) on the basis of matrix (KE-12). The specific resistance of that is 73 (${\Omega}{\cdot}cm$), and tensile strength, tensile modulus, and elongation of that is 0.45 MPa, 0.21 MPa, and 184%, respectively. Also, a simple structure of the actuator with an optimized electrode and elastomer is fabricated and its characteristic is evaluated. At the operating voltage 25 kV, the displacement of an elastomer KE-12 is 2.24 mm, and that of an elastomer KE-12 with thinner 50 (phr) is 4.05 mm. It shows a higher displacement compared to that of 3M 4910 which has similar modulus. The actuator made with elastomer and electrode of the same material (KE-12) may have advantages for fatigue life and application.

Multiresidue Analysis of 240 Pesticides in Apple and Lettuce by QuEChERS Sample Preparation and HPLC-MS/MS Analysis (QuEChERS 전처리법과 HPLC-MS/MS 기기분석을 이용한 사과와 상추 중 240종 농약의 동시분석)

  • Kwon, Hye-Young;Kim, Chan-Sub;Park, Byung-Jun;Jin, Yong-Duk;Son, Kyung-Ae;Hong, Su-Myeong;Lee, Je-Bong;Im, Geon-Jae
    • The Korean Journal of Pesticide Science
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    • v.15 no.4
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    • pp.417-433
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    • 2011
  • The study tested QuEChERS (quick, easy, cheap, effective, rugged and safe) sample preparation and HPLC-MS/ MS analysis for measurement of pesticide residues in fruit and vegetable. 240 kinds of pesticides spiked at three levels of 90, 45, 9 ng/g in lettuce and apple. For QuEChERS sample preparation, graphitized carbon black (GCB) was used for only lettuce in dispersive-SPE as absorbent. Matrix-matched standard calibration was used for quantitative analysis of HPLC-MS/MS. 218 pesticides (91%) in apple and 207 pesticides (86%) in lettuce showed recoveries in the range of 70~120% with $RSD{\leq}20%$. The lowest calibrated level (LCL) were 4.5 ng/g for 192 pesticides, 9 ng/g for 42 pesticides, 45 ng/g for 3 pesticides and 3 pesticides were not detected at all concentration levels. The results showed that the QuEChERS sample preparation and HPLC-MS/MS analysis can be applied to multi-residue analysis of pesticides in vegetables and fruits.

A Candidate Generation System based on Probabilistic Evaluation in Computer Go (확률적 평가에 기반한 컴퓨터 바둑의 후보 생성 시스템)

  • Kim, Yeong-Sang;Yu, Gi-Yeong
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.37 no.2
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    • pp.21-30
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    • 2000
  • If there exists a model that calculates the proper candidate position whenever the game of Go is in progress, it can be used for setting up the prototype of the candidate generation algorithm without using case-based reasoning. In this paper, we analyze Go through combinatorial game theory and on the basis of probability matrix (PM) showing the difference of the territory of the black and the white. We design and implement a candidate generation system(CGS) to find the candidates at a situation in Go. CGS designed in this paper can compute Influence power, safety, probability value(PV), and PM and then generate candidate positions for a present scene, once a stone is played at a scene. The basic strategy generates five candidates for the Present scene, and then chooses one with the highest PV. CGS generates the candidate which emphasizes more defence tactics than attack ones. In the opening game of computer Go, we can know that CGS which has no pattern is somewhat superior to NEMESIS which has the Joseki pattern.

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