• 한국식품영양과학회지
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• 제22권2호
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• pp.202-207
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• 1993

렌넷유청, 인삼, 감미료, 꿀, 매실 등에 종류가 다른 유산균주들을 접종하여 인삼 유청음료를 제조한 후, 일부는 발효시키고 일부는 비발효 상태로 4$^{\circ}C$ 및 30$\pm$1$^{\circ}C$에 저장하여 1, 3, 5주에 관능검사를 실시하였다. 관능검사 결과, 감미료와 꿀을 첨가하여 냉장보관 한 유산균 비발효 인삼 유청음료(A)는 단맛이 강하고 신맛, 쓴맛, 떫은맛, 뒷맛이 적어서 전체적인 평가에서 8.64~8.85으로 가장 높은평가를 받았고 Lac. caseisub-sp. casei와 Str. salivarius sbu-sp. thermophilus를 접종하여 냉장보관한 인삼 유청음료 (C)와 감미료, 꿀 및 매실을 첨가하여 실온보관한 인삼 유청음료(D)가 대체로 좋은 평가를 받았으나 실온보관한 유산균 발효 음료(E, F)는 2.92~3.58로 가장 낮은 평가를 받았으므로 이의 개선이 요구된다.

• Advances in aircraft and spacecraft science
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• 제9권3호
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• pp.169-193
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• 2022

By the present paper, both experimental and analytical models have been proposed to study the vibration behavior of partially bio-sourced sandwich panel with orthogonally stiffened core. For a variable mass fraction of Alfa fibers from 5% to 15%, impregnated in a Medapoxy STR resin, this panel were manufactured by molding the orthogonally stiffened core then attached it with both skins. Using simply supported boundary conditions, a free vibration test was carried out using an impact hammer for predicting the natural frequencies, the mode shapes and the damping coefficient versus the fibers content. In addition, an analytical model based on the Higher order Shear Deformation Theory (HSDT) was developed to predict natural frequencies and the mode shapes according to Navier's solution. From the experimental test, we have found that the frequency increases with the increase in the mass fraction of the fibers until 10%. Beyond this fraction, the frequencies give relatively lower values. For the analytical model, variation of the natural frequencies increased considerably with side-to-thickness ratio (a/H) and equivalent thickness of the core to thickness of the face (h_s/h). We concluded that, the vibration behavior was significantly influenced by geometrical and mechanical properties of the partially bio-sourced sandwich panel.

• 한국산학기술학회논문지
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• 제12권11호
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• pp.4951-4958
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• 2011

본 연구에서는 전 세계적으로 표준화된 전통적 항균제 감수성 검사방법인 CLSI(C linical and Laboratory Standards Institute)디스크 확산법과 디스크 확산법을 이용 해 MIC를 측정할 수 있도록 새롭게 고안된 E-test 방법과 최근 도입된 미량 액체 배지 희석법을 이용한 항균제 감수성 검사 자동화 장비인 MicroScan MICroSTR EP plus panel를 이용한 MIC 측정방법들의 일치도를 비교하여 MicroScan MICroS TREP plus panel 검사방법의 유용성을 관찰하고자 하였다. 대상균주는 2009년 2월부터 8월까지 6개월 동안 대전의 한 대학병원 임상환자에서 분리된 폐렴사슬알균 53균주와 알파용혈 사슬알균 51균주를 대상으로 하였으며 항 균제는 cefotaxime, chloramphenicol, clindamycin, erythromycin, levofloxacin, penicillin, tetracycline, trimethoprim/sulfamethoxazole, vancomycin 등 9가지 항균제를 평가 대상으로 하였다. 폐렴사슬알균 뿐만 아니라 알파용혈 사슬균에 대해서도 비교분석을 하였고 그 결과 알파용혈 사슬균에 대해 높은 일치율이 관찰되어 임상미생물 검사실에서 신속 정확한 최소발율 억제농도를 측정하는데 많은 도움이 되리라 생각된다.

• 한국강구조학회 논문집
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• 제18권3호
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• pp.331-337
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• 2006

최근 고성능 대형 강구조물에 많이 적용되고 있는 TMC 강재에 대해 두께 20m, 60m, 82m의 후판을 6m~16mm의여러 용접치수로 필릿용접하여 겹이음부가 있는 시험체를 제작하고, 인장시험을 통하여 필릿용접부의 강도를 측정하였다. 측정된 필릿용접부의 강도는 모재의 두께, 용접 치수, 용접축에 대한 힘의 작용방향 등을 달리한 모든 경우에 설계기준에서 적용하고 있는 강도 계산식에 의한 공칭강도의 값보다 더 큰 것으로 나타났다. 특히 60mm와 82mm 두께의 모재에 대해 국내도 로교설계기준에서 요구하고 있는 최소 용접치수보다 더 작은 용접치수를 적용한 경우에도 시험체 제작과정에 용접의 어려움이나 용접부의 결함, 균열 등이 발견되지 않았으며, 용접부의 강도도 다른 경우와 거의 동일한 수준인 것으로 나타났다.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1998년도 추계학술대회 학술발표 논문집
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• pp.211-217
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• 1998

Many practical control problems for the complex, uncertain or large-scale plants, need to simultaneously achieve a number of objectives, which may conflict or compete with each other. If the conventional optimization methods are applied to solve these control problems, the solution process may be time-consuming and the resulting solution would ofter lose its original meaning of optimality. Nevertheless, the human operators usually performs satisfactory results based on their qualitative and heuristic knowledge. In this paper, we investigate the control strategies of the human operators, and propose a fuzzy model-based multi-objective satisfactory controller. We also apply it to the automatic train operation(ATO) system for the magnetically levitated vehicles(MAGLEV). One of the human operator's strategies is to predict the control result in order to find the meaningful solution. In this paper, Takagi-Sugeno fuzzy model is used to simulated the prediction procedure. Another str tegy is to evaluate the multiple objectives with respect to their own standards. To realize this strategy, we propose the concept of a satisfactory solution and a satisfactory control scheme. The MAGLEV train is a typical example of the uncertain, complex and large-scale plants. Moreover, the ATO system has to satisfy multiple objectives, such as seed pattern tracking, stop gap accuracy, safety and riding comfort. In this paper, the speed pattern tracking controller and the automatic stop controller of the ATO system is designed based on the proposed control scheme. The effectiveness of the ATO system based on the proposed scheme is shown by the experiments with a rotary test bed and a real MAGLEV train.

• 한국동물위생학회지
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• 제45권3호
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• pp.191-199
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• 2022

We investigated the virulence genes, O-serotypes, antimicrobial resistance of pathogenic E. coli isolated from carcasses (n=455) and environmental (n=372) samples of 11 cattle and 12 pig slaughterhouses from December 2020 to December 2021. E. coli were isolated from nine carcasses (2.0%), three slaughter facilities (1.4%), two utensils (2.7%) and three abattoir workers (3.5%) from four cattle and four pig slaughterhouses. Among all isolates, 13 STEC (76.5%) were identified, followed by four EPEC (23.5%). As a result of the antibiotic susceptibility test, all isolates were resistant to at least one antimicrobial, of which 70.6% isolates showed multidrug resistance patterns. The serotypes were diverse in pigs compared to cattle, with serotypes O18, O66, O109 in cattle and O9, O76, O85, O100, O153, and O159 in pigs. In a single cattle slaughterhouse, eight STEC O66 were isolated from various types of sample (4 slaughter animal surfaces, 3 gloves, and 1 knife) with two antimicrobial resistance patterns (CHL-FIS-STR and CHL-FIS). Those two types of strain were suspected cross-contamination from utensils to slaughter animal surfaces. These results showed that pathogenic E. coli were detected in carcasses and various environmental samples in cattle and pig slaughterhouses. Nationwide monitoring and hygiene management are required to prevent cross-contamination of STEC isolate slaughterhouses.

• 한국동물위생학회지
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• 제24권1호
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• pp.31-41
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• 2001

This study was carried out to identify causative agents from california mastitis test(CMT) positive mastitic milk, and to examine the antimicrobial susceptibility of 50 heads in Seongju and Chilgok area of Gyeongbuk province. Sulfadimethoxine sodium(SMS) was intramuscularly administered once to four mastitis Infected dairy cattle at the rate of 10mg/kg body weight. After injection of SMS, the depletion rate of serum and milk from the cattle were periodically measured for five days. The CMT positive number from 50 heads showed 46% and that of 200 quarters was 47(23.5%). From 39 quarters of 47 heads 39 different microorganisms were identified. These organisms were classified into 12 species : Staphylococcus aureus 8(20.5%), Sta hemolyticus 6(15.4%), Streptococcus bovis 4(10.3%), Sta hyicus 3(7.7%), Sta epidemidis. Sta xylosus, Sta sciuri 2(5.1%), Str agalactiae 2(5.1%), Escherichia coli(10.3%), three Enterobacter cloacae(7.7%), two Ent aerogenes(5.1%) and one Salmonella spp(2.6%). As the results of antibiotic susceptibility test, gentamicin(Gm, 11 species 27 strains, 69.5%), cephalotin(Cf, 9 species 24 strains, 61.5%), sulfamethoxazole(Stx, 8 species 14 strains, 43.6%), tetracycline(Tc, 8 species 14 strains, 35.9%), and streptomycin(Sm), lincomycin(Lm), cefoperazon(Cp) and penicillin(Pc) have a highly resistance(7.7% ～5.1%). However, carbenicillin (Cb), amikacin(Ah) have no susceptible for all drugs. The mean residual concentration of SMS in serum according to the time lapsed were showed 33.964 $\pm$ 4.435ppm at the 4 hours after intramuscularly injection(AII). It was significantly(p<.05) decreased to 6.596 $\pm$ 3.402, 0.217 $\pm$ 0.119 and 0.005 $\pm$ 0.004ppm at the 1st, 3rd and 5th day AII. The mean concentration of SMS in milk was significantly(p<.05) decreased from 0.920 $\pm$ 0.42ppm to 0.084 $\pm$ 0.016ppm between 8 hours and 1 day AII. As the results of this experiments, sulfadimethoxine was residued at the level of no less than 0.01ppm in milk on the 2nd day AII. Thus, this results would be able to be used the basic index for prevention of sulfonamides residue in milk after treatment of dairy mastitis.

• The Korean Journal of Physiology and Pharmacology
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• 제14권4호
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• pp.213-221
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• 2010

The hypothalamic-pituitary-adrenal (HPA) axis is the primary endocrine system to respond to stress. The HPA axis may be affected by increased level of corticotrophin-releasing factors under chronic stress and by chronic administration of monosodium glutamate (MSG). The purpose of this study was to investigate whether chronic MSG administration aggravates chronic variable stress (CVS)-induced behavioral and hormonal changes. Twenty-four adult male Sprague-Dawley rats, weighing 200~220 g, were divided into 4 groups as follows: water administration (CON), MSG (3 g/kg) administration (MSG), CVS, and CVS with MSG (3 g/kg) administration (CVS＋MSG). In addition, for the purpose of comparing the effect on plasma corticosterone levels between chronic stress and daily care or acute stress, 2 groups were added at the end of the experiment; the 2 new groups were as follows: naive mice (n=7) and mice exposed to restraint stress for 2 h just before decapitation (A-Str, n=7). In an open field test performed after the experiment, the CVS＋MSG group significant decrease in activity. The increase in relative adrenal weights in the CVS and CVS＋MSG group was significantly greater than those in the CON and/or MSG groups. In spite of the increase in the relative adrenal weight, there was a significant decrease in the plasma corticosterone levels in the CVS＋MSG group as compared to all other groups, except the naive group. These results suggest that impaired HPA axis function as well as the decrease in the behavioral activity in adult rats can be induced by chronic MSG administration under CVS rather than CVS alone.

• 대한수의학회지
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• 제38권4호
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• pp.898-908
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• 1998

The aim of this experiments were to assess the time-interval change of motional characteristics in frozen-thawed semen of Korean native cattle (KNC) by using computer aided semen analysis (CASA) technology. Twenty-six KNC frozen semen straws were obtained from Korean KNC improvement department, livestock improvement main division, national livestock cooperatives federation in Korea. Specimens were allowed to thaw at $37^{\circ}C$ for 30 sec in water bath. Semen analysis was performed on semen image analysis system (SIAS, Medical supply, Korea) adjusted to the gate settings and used the semen droplet ($5{\mu}l$) placed on Makler counting chamber (Sefi medical instrument, Israel) prewarmed at $37^{\circ}C$. The same person used the same micropipette to fill the Makler counting chamber. A total of 150 or more of sperms were analysed in each specimen by a single trained person by scanning at least 5 to 10 fields. The measurement parameters in SIAS were as follows ; frame rate = 30 frames per sec, image capture = 1 sec, minimum motile speed = $10{\mu}m/s$, maximum countable sperm number = 400. Statistical analysis was done by Student t-test with use of the Sigma plot program on a IBM personal computer. The dancemean(DNM) and hyperactivated sperm(HYP) of frozen-thawed KNC semen kinematics were significantly decreased(p < 0.05) after 10 min of incubation at $37^{\circ}C$ water bath. But, wobble(WOB) of same sample semen was significantly increased(p < 0.05) after 10 min of incubation and significantly decrease(p < 0.05) after 60 min of same incubation. And, after 30 mim of incubation, significantly differences were found most of motion kinematics, motifity(MOT), curvilinear velocity(VCL), straight line velocity(VSL), average path velocity(VAP), amplitude of lateral head displacement(ALH), beat cross frequency(BCF), mean angular displacement(MAD), dance(DNC), on same sample semen. The DNM of KNC semen sample was variable kinematics after 30 min of incubation. Also, the linearity(LIN) and straightness(STR) was significantly decreased(p < 0.05) from 60 min of incubation. In conclusion, the AI within 30 min after thawing of frozen semen can be an effective method for obtaining high fertility rate in KNC reproductive program.

• 한국동물위생학회지
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• 제34권1호
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• pp.45-54
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• 2011

This study was conducted to investigate the distribution of Salmonella spp. from pigs and cattle in slaughterhouse, the antimicrobial resistance pattern and the prevalence of resistance genes of isolates. A total of 640 fecal samples from pigs and cattle in slaughterhouse were collected for isolation of Salmonella spp.. Isolation rate was revealed as 15% in pigs and 1.6% in cattle. As result of serotyping, group B (56.6%) were identified as most common in pigs and cattle isolates, in order of group C (24.5%) and group E (15.1%). S. Typhimurium (50.9%) was most common serotype. The major serotypes were in order of S. Rissen and S. London (11.3%) and S. Riggil (7.6%). In antimicrobial test, all isolates were demonstrates susceptibility to nitrofurantoin. But isolates were revealed resistance other antibiotics in order of tetracycline (64.6%), streptomycin (68.3%), ampicillin and amoxicillin (56.3%) and spectinomycin (47.9%). With polymerase chain reaction, antimicrobial resistance gene strA (75.0%) and aadA1 (3.1%) were detected in streptomycin resistance isolates and tetA (94.3%) and tetB (11.3%) gene were detected in tetracycline resistant isolates, but tetG was not detected. Class 1 integron gene was detected in all Salmonella isolates.