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191.
Han Jo Bae Youn-Sung Kim Soon-Yong Chun Un-Ho Ji Mu Han Kim Sung Soo Han 《Fibers and Polymers》2008,9(3):323-327
High regularity is important in manufacturing spun yarn. Among controllers used in regularity control, existing PID controller
is suitable for linear time-invariant systems but not for the control of sliver draft systems with non-linear characteristic.
Thus, the present study designed a knowledge-based fuzzy controller in consideration of disturbance and non-linear characteristic
of sliver draft systems. RLS (Recursive Least Squares) was used as an estimation algorithm to formulate a model used in computer
simulation for implementing the controller, and real time estimation was made using real data from draft systems to get a
model close to actual systems. This research used a estimation model in designing a knowledge-based controller that minimizes
the variation of control response to the sliver linear density of the system, and the result of linear density control was
used to prove the superiority of the controller in control performance through CV%. 相似文献
192.
We report herein a superhyrodrophobic poly(ethylene terephthalate) (PET) fabric prepared through a biomimetic method of the
Lotus effect. To attain the Lotus effect on the PET fabrics, physical roughness and chemical hydrophobicity were controlled
by adopting silica nanoparticles and a commercial water-repellent agent, respectively. For this, narrow-size distributed silica
nano-particles were prepared by a sol-gel process. The water contact angle on PET fabric treated with both silica nanoparticles
and water-repellent agent reached 158°, which was much higher than 137° reached by the fabric treated with the water-repellent
agent only. 相似文献
193.
Young Cheol Kim Jang Hoon Lee Yeoung-Seuk Bae Bo-Kyoon Sohn Seur Kee Park 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(4):443-450
In ginseng fields, Alternaria blight, caused by Alternaria panax, and anthracnose, caused by Colletotrichum gloeosporoides, have become serious problems in Korea, and control of these diseases relies mainly on intensive applications of fungicides.
In an effort to develop an effective environmentally-friendly control system, we utilized preventative control approaches
including rain shelter shading plates and the removal of dead plants, as well as a curative control approach, such as the
application of microbial agents. In the presence of rain shelter shading plates, the occurrence of Alternaria blight and anthracnose
decreased significantly compared to that seen with polyethylene shading nets. In addition, the eradication of dead ginseng
plants, which harboured abundant spores of the pathogens, significantly reduced the incidence of both diseases. In fields
with rain shelter shading plates and in which dead plants were eradicated, four applications of a bioformulated product containing
chitinolytic bacterial strains in a simple medium containing chitin provided control similar in effect to that observed with
the application of the fungicide under low disease pressure. The efficacy of the bioformulated product was decreased slightly
under severe disease pressure. These findings indicate that integration of the three disease management measures might constitute
a new effective and environmentally-friendly system for the control of Alternaria blight and anthracnose in Korean ginseng
fields. 相似文献
194.
Lewis CW Williamson AK Chen AC Bae WC Temple MM Wong WV Nugent GE James SP Wheeler DL Sah RL Kawcak CE 《American journal of veterinary research》2005,66(10):1823-1829
OBJECTIVE: To determine and correlate subchondral bone mineral density and overlying cartilage structure and tensile integrity in mature healthy equine stifle (low magnitude loading) and metacarpophalangeal (high magnitude loading) joints. ANIMALS: 8 healthy horses, 2 to 3 years of age. PROCEDURE: Osteochondral samples were acquired from the medial femoral condyle (FC) and medial trochlear ridge (TR) of the stifle joint and from the dorsal (MC3D) and palmar (MC3P) aspects of the distal medial third metacarpal condyles of the metacarpophalangeal joint. Articular cartilage surface fibrillation (evaluated via India ink staining) and tensile biomechanical properties were determined. The volumetric bone mineral density (vBMD) of the underlying subchondral plate was assessed via dual-energy x-ray absorptiometry. RESULTS: Cartilage staining (fibrillation), tensile moduli, tensile strength, and vBMD were greater in the MC3D and MC3P locations, compared with the FC and TR locations, whereas tensile strain at failure was less in MC3D and MC3P locations than FC and TR locations. Cartilage tensile moduli correlated positively with vBMD, whereas cartilage staining and tensile strain at failure correlated negatively with vBMD. CONCLUSIONS AND CLINICAL RELEVANCE: In areas of high joint loading, the subchondral bone had high vBMD and the articular cartilage surface layer had high tensile stiffness but signs of structural wear (fibrillation and low failure strain). The site-dependent variations and relationships in this study support the concept that articular cartilage and subchondral bone normally adapt to physiologic loading in a coordinated way. 相似文献
195.
Yoo MH Kim JT Rhee CH Park MJ Bae IJ Yi NY Jeong MB Jeong SM Nam TC Seo KM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(9):1091-1095
To compare the antiangiogenic effects of tetraarsenic oxide (As4O6) with those of diarsenic oxide (As2O3) in the rat cornea, rat cornea micropocket assay was conducted to induce angiogenesis by implantation of the pellet contained 1.0 ng of nerve growth factor (NGF). Ten of thirty eyes of Sprague-Dawley rats were randomly assigned to one of three groups, namely, control group (no medication), As2O3 group (50 mg/kg As2O3, PO, s.i.d.), and As4O6 group (50 mg/kg As4O6, PO, s.i.d.). After implantation, the number of new vessels, vessel length and clock hour of neovascularization were examined under the microscope from day 3 to day 7. The area of neovascularization was calculated using a mathematical formula. Although new vessels in control and As2O3 groups were first noticed at day 3, whereas those of As4O6 group were first observed on day 5. The number, length, clock hour of neovascularization and areas of the vessels in As4O6 group showed more significant inhibition than those of control and As2O3 groups from day 5 (P<0.05). However, there were no differences in all parameters between control group and As2O3 group during the entire study period. These results showed that As4O6 had antiangiogenic effects on the new vessels induced by NGF in the rat cornea. 相似文献
196.
Bae JS Jin HK Jang KH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(10):1205-1211
Polysaccharides isolated from fungi, Phellinus spp. is well-known material with anti-tumor and anti-inflammatory properties. We have assessed the adhesion- and abscess-reducing capacity of carboxymethylcellulose (CMC) and polysaccharides from Phellinus spp. combination in a rat peritonitis model. In 72 Sprague-Dawley rats, experimental peritonitis was induced by means of the cecal ligation and puncture model (CLP). After 24 hr, the abdomen was reopened and the ligated cecum was resected. Peritoneal fluid samples were taken for microbiological examination. Rats were randomly assigned to 6 groups: ringer lactate solution (RL group), polysaccharides from Phellinus gilvus (PG group) and Phellinus linteus (PL group), carboxymethylcellulose (CMC group), and their combinations (PG+CMC and PL+CMC groups). Adhesions and abscesses were noted at day 7 after CLP. RT-PCR assay for urokinase-type plasminogen activator (uPA), its cellular receptor (uPAR), and tumor necrosis factor (TNF)-alpha was performed to assess the cecal tissue. Microbiological examination showed polymicrobial bacterial peritonitis. Adhesion formation was significantly reduced in PG+CMC and PL+CMC groups (P<0.05). The incidence of abscesses was reduced in all treated groups except the RL group (P<0.05). uPA, uPAR, and TNF-alpha mRNA were highly expressed in the PG+CMC and PL+CMC groups, as compared to the RL group. We concluded that the combination of polysaccharides and CMC had significant adhesion- and abscess-reducing effects compared with their single treatment and the effects may act by modifying the fibrinolytic capacity of uPA, uPAR and TNF-alpha produced from activated macrophages in a rat peritonitis model. 相似文献
197.
198.
Lee YJ Kim HJ Park CK Kim KS Bae DH Kang MS Cho JK Kim AR Kim JW Kim BH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(4):399-404
The purpose of this study was to investigate the biological and genetic characterization of persistent Salmonella isolates in an integrated broiler chicken operation, in an attempt to elucidate the source of contamination. From the breeder farm, the hatchery, the broiler farm and the chicken slaughter house of an integrated broiler chicken operation, a total of 6 serotypes were observed. Although S. Heidelberg was not detected in the broiler farm, it was consistently found in the breeder farm, the hatchery and the chicken slaughter house. Also, S. Enteritidis and S. Senftenberg were found in the hatchery and the chicken slaughter house, and the hatchery and the broiler farm, respectively. S. Gallinarum and S. Blockley were found only in the broiler farm, and S. Virchow was only recovered in the chicken slaughter house. Isolated S. Heidelberg, S. Enteritidis and S. Senftenberg strains were divided into 3, 5 and 7 types, respectively, on the basis of all properties. Especially, S. Senftenberg isolates, divided into four types by their antimicrobial resistance patterns, were all obviously the XbaI PFGE pattern. Also, four S. Enteritidis isolates resistant to nalidixic acid showed a difference in phage type and PFGE pattern. Such a different pattern was shown despite Salmonella isolates originating from an integrated broiler operation, suggesting that further epidemiological studies on many integrated chicken companies in Korea are needed. 相似文献
199.
Choi JS Kim JS Byun IS Lee DH Lee MJ Park BH Lee C Yoon D Cheong H Lee KH Son YW Park JY Salmeron M 《Science (New York, N.Y.)》2011,333(6042):607-610
Graphene produced by exfoliation has not been able to provide an ideal graphene with performance comparable to that predicted by theory, and structural and/or electronic defects have been proposed as one cause of reduced performance. We report the observation of domains on exfoliated monolayer graphene that differ by their friction characteristics, as measured by friction force microscopy. Angle-dependent scanning revealed friction anisotropy with a periodicity of 180° on each friction domain. The friction anisotropy decreased as the applied load increased. We propose that the domains arise from ripple distortions that give rise to anisotropic friction in each domain as a result of the anisotropic puckering of the graphene. 相似文献
200.
Soo-Hyeon Kim Byung-Joon Seung Seung-Hee Cho Ha-Young Lim Min-Kyung Bae Kyung-Yeon Eo Yong-Gu Yeo Jang-Won Son Jung-Hyang Sur 《Journal of veterinary diagnostic investigation》2021,33(2):366
A 36-y-old white rhinoceros (Ceratotherium simum) was presented with respiratory distress, sanguineous vaginal exudate, and anorexia. The clinical signs progressed over 40 d, and the rhinoceros died. Autopsy revealed significant ascites; a unilateral, 12.5-cm diameter, polypoid mass in the left ovary; a white, firm transmural mass in the right uterine horn; a white, friable mass in the lung; and white-to-tan, friable small nodules in the diaphragm. Histologic examination revealed similar neoplastic cells in the masses in all 4 locations, composed predominantly of epithelial cells proliferating in a tubulopapillary pattern with significant nuclear atypia and numerous atypical mitotic figures (18–42 per 2.37 mm2). Immunohistochemistry for CK7 (cytokeratin 7) and CK20 (cytokeratin 20) suggest that the ovarian, pulmonary, and diaphragmatic lesions were of ovarian origin and that the ovary was the primary tumor site. 相似文献