• 대한교통학회지
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• 제18권5호
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• pp.57-67
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• 2000

본 논문에서는 추종 모형을 이용한 미시 교통류 시뮬레이션 모형(DETSIM)과 현장 조사 자료를 이용하여 단속류에서 링크의 통행시간을 추정하는 2개의 모형을 개발하였다. 2개의 모형은 통행시간과 교통변수가 가지는 비선형성에 적합하도록 퍼지논리 제어기를 이용하고 있다. 시뮬레이션의 수행결과와 현장 조사에 의하면 검지기로부터 발생하는 교통량, 점유율, 속도 자료중 링크의 통행시간을 가장 잘 반영하는 것은 점유율이며, 지점속도와 교통량은 부분적으로 통행시간에 대한 설명력을 가진다. 그러나, 통행시간을 추정하는데 적용되는 교통량, 점유율 및 지점속도는 동일한 교통상황에 대해서도 검지기의 위치에 따라 다른 값을 가지게 된다 본 연구에서는 이러한 문제를 극복하기 위한 2개의 통행시간 추정 모형을 개발하였으며. 이것은 교통량과 점유율을 이용하여 통행시간을 추정하는 모형(FETSYO)과 검지기로부터 발생되는 점유율과 지점속도를 이용하여 통행속도를 추정하는 모형(FETTOS)으로 구분된다. FETSVO모형은 이식성이 뛰어나며, FETTOS 모형은 신호주기와 녹색신호시간비 등의 자료가 요구되나, 통행시간을 직접추정하고 통행시간에 민감한 자료에 의하기 때문에 FETSVO모형보다 우수한 것으로 나타났다.

• 대한지리학회지
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• 제41권1호
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• pp.22-38
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• 2006

본 논문은 스위스 독일 프랑스 접경지역에서의 월경적(越境的) 상호작용과 초경계적 지역정체성 형성여부를 고찰하고자 한다. 먼저 이 논문은 '경계와 접경지역' 에 관한 최근의 연구들을 검토하여, 이 주제에 대한 이론적 토대와 월경협력의 유형을 구축한다. 이를 기반으로 유러리젼 '라인강 상류' 의 월경적 협력과정을 분석하고 본 연구의 사례지역인 '레기오 트리레나' 에서의 일상적인 월경적 이동(통근, 쇼핑, 주택)을 연구한다. 유러리젼 '라인강 상류' 에서의 월경적 협력은 다양한 활동영역을 지닌 여러 위원회에 의해 추진되며 러시아 인형 바부슈카처럼 중층적으로 구성되어 있다. 스위스 독일 프랑스 간의 경제적인 차이는 3국간의 대량 월경이동을 유발한다. 이 논문은 이러한 월경이동을 울만이 제시한 공간적 상호작용의 3대 기반(상호보완성, 이동가능성, 개입기회)에 입각하여 해석해 보았다. 마지막으로 본 논문은 경제적 장벽의 제거가 초경계적 지역정체성 또는 초국경적 공동체 정신을 창출하기에는 충분치 않다는 것을 보여준다.

• 농촌지도와개발
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• 제4권1호
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• pp.305-315
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• 1997

The propose of this study was to analyze the relationships among the levels of training & development evaluation (reaction, learning, transfer). The study has been conducted on 730 trainees who attended in the basic accounting program in L training and development institution through three incidents of tracked research such as reaction survey right after the conclusion of training, learning evaluation through test, and an evaluation of the transferability after 3 months of training. Questionnaires and test papers for analyses were used after their reliability, validity, difficulty, and discrimination have been verified on a pre-test. The research has been conducted for six months from 4 March 1996 to the end of August 1996, and data have been collected through direct research and survey through mail. The collected data have been worked on at SAS program for Windows with a statistical significance level of 5%. Statistical method that had been used was Pearson's correlation coefficient. The result and conclusion acquired from this study were as follows: Between reaction and learning, learning and transfer of training, only a weak positive correlation exists and explanation or prediction variance showing hierarchical relationship was quite weak with 1%. Thus, this research not only does not strongly support Kirkpatrick(1976)'s hierarchical model of $reaction{\rightarrow}learning{\rightarrow}transfer$, but also indicates that the separate measurement on each levels of training evaluation needs to be done. On the other hand, there was a relatively strong positive correlation between reaction and transfer of training. Based on the result, the conclusion, and the restriction perceived through this study, the following suggestions were made. 1. There is a need to empirically analyze and verify the hierarchy of all levels of training evaluation including the evaluation of the fourth level (result) such as organizational productivity, organizational satisfaction, and separation rate. 2. A great deal of efforts will be needed to systematically analyze what the relationships are among the methods measuring the level of evaluation of the training and development, and to apply this result to the training field.

• 대한수의학회지
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• 제20권2호
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• pp.113-118
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• 1980

Total of 11 strains of Ldctobacillus isolated from lactobacillus-fermented milk and-beverage in March 1980 were examined for susceptibility to 8 drugs, and transferability and transfer frequency of R plasmids by conjugation. Of 11 isolates each 2 strains were classified as L. cellobiosus and L. helveticus, each 1 strain as L. plantarum, L. lactis, L. acidophilus, L. delbrueckii, L. casei subsp. casei, L. casei subsp, tolerans and L. salivarius subsp, salivarius by Bergey's manual. Resistance was the most active to na lidixic acid(NA), followed in decreasing order by chloramphenicol(CP), ampicillin(AP), kanamycin(KM) and streptomycin(SM). All of isolates were resistant to NA, each 10 strains to CP and AP, 7strains to KM and 6 strains to SM, indicating all of the isolates were resistant to two or more drugs in combination. No strain was resistant to erythromycin(EM), penicillin(PC) and tetracycline(TC). The most frequently encountered resistant patterns were CP NA AP SM KM, followed by CP NA AP KM, NA AP, CP NA, CP NA AP and CP NA AP SM in order. Transfer experiment of drug resistance showed that of 11 resistant strains, 9 strains transferred parts of their resistance to AP or AP CP or SM AP, indicating 9 strains carried R plasmids determining R(AP), R(AP CP) and R(SM AP). The conjugal frequency of R(AP) from Lactobacillus to E. coli ranged from 2.5{\times}10^{-1} to $5.6{\times}10^{-4}%$, that of R(CP) ranged from 5.0{\times}10^{-1} to 5.0{\times}10^{-3}% and that of R(SM) ranged from 6.0{\times}10^{-5} to 1.4{\times}10^{-5}%, at $37^{\circ}C$ for 18 hours of incubation.

• Journal of Microbiology and Biotechnology
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• 제26권2호
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• pp.270-276
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• 2016

Extended-spectrum β-lactamases (ESBLs), particularly those of the CTX-M types, are the predominant resistance determinants of Escherichia coli that are rapidly spreading worldwide. To determine CTX-M types, E. coli isolates were collected from retail chickens (n = 390) and environmental samples from chicken farms (n = 32) and slaughterhouses (n = 67) in Korea. Fifteen strains harboring bla_CTX-M genes were isolated from 358 E. coli isolates. The most common CTX-M type was eight of CTX-M-15, followed by six of CTX-M-1 and one of CTX-M-14. The bla_CTX-M genes were identified in the isolates from retail chickens (n = 9), followed by feces, water pipes, floors, and walls. Conjugations confirmed the transferability of the plasmids carrying bla_CTX-M genes to the recipient E. coli J53 strain. Furthermore, eight addiction systems carried by the replicons in CTX-M types were confirmed. The dominant system was identified as ccdAB, vagCD, and pndAC in donor strains and transconjugants. The clonal relationship between the two strains carrying bla_CTX-M genes indicates that E. coli may transmit from the farm to retail chickens, suggesting a possible public health risk. Our findings demonstrate that the detection of CTX-M types in E. coli isolates is important for tracking ESBL production in animals, and suggest linkage of multiple addiction systems in plasmids bearing bla_CTX-M genes.

• 한국자원식물학회지
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• 제30권3호
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• pp.287-297
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• 2017

Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. In this study, a total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST-SSR markers were developed based on the trials of transferability of these primers in little millet. The EST-SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. The average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. The polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST-SSR markers in assessing genomic relationships in little millet. The findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.

• Journal of Microbiology and Biotechnology
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• 제31권10호
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• pp.1420-1429
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• 2021

The safety of the probiotic strain Q180, which exerts postprandial lipid-lowering effects, was bioinformatically and phenotypically evaluated. The genome of strain Q180 was completely sequenced, and single circular chromosome of 3,197,263 bp without any plasmid was generated. Phylogenetic and related analyses using16S rRNA gene and whole-genome sequences revealed that strain Q180 is a member of Lactiplantibacillus (Lp., formerly Lactobacillus) plantarum. Antimicrobial resistance (AMR) genes were bioinformatically analyzed using all Lp. plantarum genomes available in GenBank, which showed that AMR genes are present differently depending on Lp. plantarum strains. Bioinformatic analysis demonstrated that some mobile genetic elements such as prophages and insertion sequences were identified in the genome of strain Q180, but because they did not contain harmful genes such as AMR genes and virulence factor (VF)- and toxin-related genes, it was suggested that there is no transferability of harmful genes. The minimum inhibition concentrations of seven tested antibiotics suggested by the European Food Safety Authority guidelines were slightly lower than or equal to the microbiological cut-off values for Lp. plantarum. Strain Q180 did not show hemolytic and gelatinase activities and biogenic amine-producing ability. Taken together, this study demonstrated the safety of strain Q180 in terms of absence of AMR genes and VF- and toxin-related genes as a probiotic strain.

• 정보보호학회논문지
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• 제5권1호
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• pp.37-50
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• 1995

반도체 기술의 발달은 스마트카드의 실용화를 가능케하였고 더나아가서 컴퓨터 기술과 암호 기술의 결합은 전자현금을 포함하는 전자지갑의 실현을 가능케 하였다. 지금까지 연구된 전자현금에 대한 연구는 고객의 익명성 보장, 재사용 검출, 그리고 현금의 분할 사용에 초점을 맞추어 수행되어 왔다. 본 논문에서는 이산대수 문제와 소인수분해 문제에 바탕을 둔 새로운 전자현금 방식을 제시하며, 제시된 전자현금 방식의 특성을 분석한다. 제시된 전자현금 방식은 전자현금의 발급과정에서 은닉 디지틀 서명 기법에 바탕을 두고 잇으며, 전자현금 지불 과정에서 Schnorr의 인증 기법을 이용하여 현금의 정당성을 확인하며, 일방향 해쉬함수와 이산대수문제에 기반을 둔 계층적 구조표를 이용하여 전자현금의 분할 사용을 가능케 한다. 또한 현금의 다른 고객으로의 전이가 가능하며, 현금을 한번만 사용하는 경우 고객의 익명성을 보장하지만 동일한 현금을 두 번 이상 사용하는 경우에는 고객의 신원이 검출된다. 따라서, 본 방식은 고객의 불법적인 전자현금 사용을 방지할 수 있고, 고객 측면에서 계산적 복잡도를 감소시킬 수 있는 방식이다.

• Journal of Microbiology and Biotechnology
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• 제30권12호
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• pp.1862-1869
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• 2020

The spread of plasmid-mediated colistin resistance has posed a serious threat to public health owing to its effects on the emergence of pandrug-resistant bacteria. In this study, we investigated the prevalence and characteristics of mcr-1-positive Escherichia coli isolated from retail meat samples in Korea. In total, 1,205 E. coli strains were isolated from 3,234 retail meat samples in Korea. All E. coli strains were subjected to antimicrobial susceptibility testing and were examined for the presence of mcr-1 gene. All mcr-1-positive E. coli (n = 10, 0.8%) from retail meat were subjected to pulse-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS). The transferability of mcr-1 gene was determined by conjugation assays. The mcr-1-positive strains exhibited diverse clonal types. Our mcr-1 genes were located in plasmids belonged to the IncI2 (n = 1) and IncX4 (n = 8) types, which were reported to be prevalent in Asia and worldwide, respectively. Most mcr-1 genes from mcr-1-positive strains (9/10) were transferable to the recipient strain and the transfer frequencies ranged from 2.4 × 10-3 to 9.8 × 10-6. Our data suggest that the specific types of plasmid may play an important role in spreading plasmid-mediated colistin resistance in Korea. Furthermore, our findings suggest that the retail meat may be an important tool for disseminating plasmid-mediated colistin resistance.

• 한국환경농학회지
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• 제40권1호
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• pp.60-66
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• 2021

BACKGROUND: The concern over heavy metal(loid)s in arable land and agricultural products increases for public health in recent years. This study aims to identify transition characteristics of heavy metal(loid)s and to assess dietary risk in barley grown at the major producing districts in Korea. METHODS AND RESULTS: The soil and barley samples were collected from 38 locations around the major producing districts at Jeollabuk-do in Korea for the propose of examining the concentrations of heavy metal(loid)s. The 34 barley samples were separately purchased on the market for the same survey. The average concentration and range of arsenic (As), cadmium (Cd) and lead (Pb) in barley grown at the major producing districts in Korea were 0.037 (0.016-0.094), 0.028 (0.004-0.083) and 0.137 (0.107-0.212) mg kg-1, respectively. Currently, the maximum allowable level for barley Pb is set at 0.2 mg kg-1 in Korea, and the monitoring results suggested that some samples exceeded the maximum allowable level and required appropriate farming management. Bio-concentration factor values by heavy metal(loid)s in barley were high at Cd, copper (Cu) and zinc (Zn), similar to other crops, while As and Pb were low, indicating low transferability. CONCLUSION: Human exposure to As, Cd and Pb through dietary intake of barley might not cause adverse health effects due to relatively low concentrations, although the Pb in some barley was detected higher than the maximum allowable level. Further study on uptake and accumulation mechanism of Pb by barley might be required to assess the human health risk associated with soil contamination.