• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.375-381
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• 2004

Recently, the evolution in production techniques (e.g. high-speed milling) and the complex shapes involved in modem production design has been increasingly popular. The key to the achievement is a drastic improvement of the dynamic behavior of the machine tool axes used in production machinery. The more complex these tool paths the higher the speed and acceleration requirements. But it is very difficult to reach the target for high speed machine tool because of the limitations of servo system and motion control system. However the direct drive design of machine tool axes, which is based on linear motors and which recently appeared on the market, is a viable candidate to meet the ever increasing demands, because of these advantages such as no backlash, less friction, more mechanical simplicity and very higher acceleration and velocity comparing to the traditional system. This paper focused on the performance tests of the high speed horizontal machine tool based on linear motor. Especially, dynamic characteristics were investigated through circular test and circular form machining test is carried out considering many important parameter. Therefore these several experiments is used to be evaluated the model for prediction of circular motion error and circular machined error.

• Asian-Australasian Journal of Animal Sciences
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• 제14권9호
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• pp.1209-1215
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• 2001

We conducted this study to investigate 24 h leptin profiles and to ascertain whether leptin secretion occurs in a pulsatile manner in cattle. Plasma leptin concentrations were measured every 10 min for 24 h in five Holstein steers aged 10 months. Simultaneously, feeding behavior was recorded every 5 min during this experiment. In two of the five cattle, leptin showed diurnal rhythmicity, which could be described by a cosine, with peaks between 15:00 and 16:00 and nadirs at around midnight. Pulsatile leptin release was quantified by model-free Cluster analysis. Plasma leptin showed a pulsatile pattern in all cattle, with an average number of pulses at 15 peaks/24 h. The daily number of pulses was not related to total time spent eating, ruminating or chewing. However, when divided into six 4 h time intervals, time spent ruminating was positively related with pulse number (p=0.05) in cattle showing no diurnal plasma leptin variation. These results suggest that cattle may have unique diurnal variation and pulsatile patterns of plasma leptin, differing from those of monogastric animals.

• The Plant Pathology Journal
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• 제29권3호
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• pp.330-337
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• 2013

Rice stripe virus (RSV), the type member of the genus Tenuivirus, transmits by the feeding behavior of small brown planthopper (SBPH), Laodelphax striatellus. To investigate the interactions between the virus and vector insect, total RNA was extracted from RSV-viruliferous SBPH (RVLS) and non-viruliferous SBPH (NVLS) adults to construct expressed sequence tag databases for comparative transcriptome analysis. Over 30 million bases were sequenced by 454 pyrosequencing to construct 1,538 and 953 of isotigs from the mRNA of RVLS and NVLS, respectively. The gene ontology (GO) analysis demonstrated that both libraries have similar GO structures, however, the gene expression pattern analysis revealed that 17.8% and 16.8% of isotigs were up- and down-regulated significantly in the RVLS, respectively. These RSV-dependently regulated genes possibly have important roles in the physiology of SBPH, transmission of RSV, and RSV and SBPH interaction.

• Journal of Animal Science and Technology
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• 제62권2호
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• pp.247-262
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• 2020

Birth weight and subsequent weight gain is of critical importance in the survival and performance of piglets on a commercial swine farm setting. Oropharyngeal microbiome could influence immunity, and feeding behavior thus impacting health and weight gain. We used 16S rRNA gene sequencing to profile the composition and predicted metabolic functionality of the oropharyngeal microbiota in 8 piglets (4 with a birthweight ≤ 1.0 kg and 4 with a birthweight ≥ 1.7 kg) at 11, 26, and 63 days of age. We found 9 genera that were significantly associated with average daily gain (ADG) at 11 days (false discovery rate, FDR < 0.05) and 26 days of age (FDR < 0.1), respectively. The microbial functional profile revealed several pathways associated with ADG (FDR < 0.05). Among these, pathways related to degradation of catechols showed a positive association with ADG at 11, 26, and 63 days of age, implying a potential to breakdown the host-derived catecholamines. We also noted that pathways related to the biodegradation of nucleosides and nucleotides increased with ADG during the pre-weaning phase, while those involved in their biosynthesis decreased. Our findings provide insights into the oropharyngeal microbial memberships and metabolic pathways that are involved in a piglet's weight gain. Thus, providing a basis for the development of strategies aimed at improving weight gain in pigs.

• 폴리머
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• 제39권2호
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• pp.261-267
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• 2015

The inclusion complexes (ICs) between polylactic acid (PLA) and ${\beta}$-cyclodextrin (CD) were prepared by co-precipitation method in this work. The orthogonal experiments were designed to investigate the influence of different factors on the formation of inclusion complexes. The results suggested that the optimum scheme of inclusion compounds could be obtained when the feeding ratio of CD to PLA (wt%) was 20:1, stirring speed was 6 kr/min and the stirring time was 30 min. The structures and properties of the inclusion complexes were characterized by $^1H$ NMR, FTIR, DSC, FT-Raman, XRD and TGA. The DSC results demonstrated that the crystallization behavior of the inclusion complexes nearly disappeared. It was found that ${\beta}$-CD-PLA inclusion complex had a better thermal stability compared with the neat PLA. The model of the inclusion complexes was proposed on the basis of XRD, $^1H$ NMR and DSC results.

• 한국수산과학회지
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• 제36권6호
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• pp.735-742
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• 2003

In order to develop a logical method for using selective fishing gear, the behaviour and habits of the aquatic animals must be investigated. However, until now, little national research has been carried out to investigate the behaviour and habits of the common octopus (Octopus minor). The purpose of this study henceforth, is to compile necessary behavioral data to develop fishing gear to catch the common octopus. Behaviour and habits of the common octopus were observed while breeding in a water tank from February to May, 2003. The feeding habits of common octopus are more vigorous at night than in the daytime. The common octopus feeds on 1-4 bait crabs per day and consume each crab in 40-50 min. The sensory organs of the common octopus are more influenced by the sense of touch and smell, than by vision. Using live bait is more effective and advantageous than using dead bait, as the common octopus responded more to live bait. The hiding habits of the common octopus were very intensive, as they hid around all the shelters that were provided in this study. They demonstrated territorial behavior and struggled to maintain their sphere of influence. In addition, out of the various colors for shelters and bait supplied, the common octopus preferred light colors.

• Child Health Nursing Research
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• 제13권4호
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• pp.416-426
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• 2007

The purposes of this descriptive survey study were to describe antenatal depression and level of mother-fetal interaction, and to assess mother's behavior and feeling during mother-fetal interaction, in order to develop a base for nursing intervention programs for mothers who have antenatal depression. Method: Data were collected from 174 pregnant women who visited one public health center and OBGY clinic in Gangneung city. The instrument used for this study was a self-report questionnaire to identify depression (BDI), and mother-fetal interaction. Results: Of the mothers 63.2% were in the normal range for antenatal depression, 21.3% in the mild group and 15.5% were in the moderate to severe group. For antenatal depression, there were significant differences among the income, planned pregnant, health status, marriage satisfaction, family support, husband's love. The mean for mother-fetal interaction was $29.88{\pm}4.91$. For mother-infant interaction, there were significant differences in education, income, pregnant number, delivery number, feeding plan, marriage satisfaction, family support, husband's love. There was a weak correlations between antenatal depression and mother-fetal interaction but it did not reach statistical significance. Conclusion: Antenatal depression and mother-fetal interaction influence fetal development. It is essential to assess and provide immediate care to mothers who have antenatal depression and lower level mother-fetal Interaction.

• 조명전기설비학회논문지
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• 제24권5호
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• pp.114-121
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• 2010

본 논문에서는 대지저항률과 매설지선의 길이 그리고 접지전류의 인가점에 따른 매설지선 접지임피던스의 주파수 의존성에 대하여 살펴보았다. 단일 구조와 2층 구조의 대지에 설치된 매설지선의 접지임피던스를 1[kHz]에서 10[MHz]의 주파수 범위에서 측정하고 분석하였다. 그 결과, 접지임피던스의 주파수 의존성은 대지저항률에 크게 영향을 받는 것으로 나타났으며, 그리고 높은 대지저항률의 대지에 설치된 매설지선의 접지임피던스는 수십 [kHz] 이하의 주파수에서 용량성 특성을 나타내었다. 높은 대지저항률을 갖는 대지에 설치된 매설지선의 끝단에 접지전류를 인가한 경우 접지임피던스는 높은 주파수 영역에서 증가하였다.

• 한국응용곤충학회지
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• 제30권3호
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• pp.174-179
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• 1991

1986~1990년에 3년근 인삼포장에서 참검정풍뎅이 유충에 의한 춘기 피해 양상을 조사한 결과 인삼포장의 바깥쪽일수록 피해가 심하였는데 이는 참검정풍뎅이 자성충의 dirks 이동 습성 때문으로 보인다. 3령 유충에 의한 3년근 인삼의 피해부는 뿌리 동례의 상부, 중부, 하부 또는 뿌리 전체였으며 드물게 지하부 줄게에도 피해가 있었다. 섭식기 3령층의 평균 서식 깊이는 인삼 유묘, 2년근, 3년근, 쑥에서 각각 3.2cn, 5.6cm, 6.6cm, 4.9cm 였다. 춘기의 참검정풍뎅이 유충에 의한 인삼의 피해는 주러 5월 중순에서 7월 상순에 발생하였고 강우량이 증가할 경우 피해가 일시적으로 감소하는 것으로 보였다.

• Molecules and Cells
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• 제39권4호
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• pp.358-366
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• 2016

The digestive system is gaining interest as a major regulator of various functions including immune defense, nutrient accumulation, and regulation of feeding behavior, aside from its conventional function as a digestive organ. The Drosophila midgut epithelium is completely renewed every 1-2 weeks due to differentiation of pluripotent intestinal stem cells in the midgut. Intestinal stem cells constantly divide and differentiate into enterocytes that secrete digestive enzymes and absorb nutrients, or enteroendocrine cells that secrete regulatory peptides. Regulatory peptides have important roles in development and metabolism, but study has mainly focused on expression and functions in the nervous system, and not much is known about the roles in endocrine functions of enteroendocrine cells. We systemically examined the expression of 45 regulatory peptide genes in the Drosophila midgut, and verified that at least 10 genes are expressed in the midgut enteroendocrine cells through RT-PCR, in situ hybridization, antisera, and 25 regulatory peptide-GAL transgenes. The Drosophila midgut is highly compartmentalized, and individual peptides in enteroendocrine cells were observed to express in specific regions of the midgut. We also confirmed that some peptides expressed in the same region of the midgut are expressed in mutually exclusive enteroendocrine cells. These results indicate that the midgut enteroendocrine cells are functionally differentiated into different subgroups. Through this study, we have established a basis to study regulatory peptide functions in enteroendocrine cells as well as the complex organization of enteroendocrine cells in the Drosophila midgut.