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Design and control of a proof-of-concept active jet engine intake using shape memory alloy actuators

  • Song, Gangbing;Ma, Ning;Li, Luyu;Penney, Nick;Barr, Todd;Lee, Ho-Jun;Arnold, Steve
    • Smart Structures and Systems
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    • v.7 no.1
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    • pp.1-13
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    • 2011
  • It has been shown in the literature that active adjustment of the intake area of a jet engine has potential to improve its fuel efficiency. This paper presents the design and control of a novel proof-of-concept active jet engine intake using Nickel-Titanium (Ni-Ti or Nitinol) shape memory alloy (SMA) wire actuators. The Nitinol SMA material is used in this research due to its advantages of high power-to-weight ratio and electrical resistive actuation. The Nitinol SMA material can be fabricated into a variety of shapes, such as strips, foils, rods and wires. In this paper, SMA wires are used due to its ability to generate a large strain: up to 6% for repeated operations. The proposed proof-of-concept engine intake employs overlapping leaves in a concentric configuration. Each leaf is mounted on a supporting bar than can rotate. The supporting bars are actuated by an SMA wire actuator in a ring configuration. Electrical resistive heating is used to actuate the SMA wire actuator and rotate the supporting bars. To enable feedback control, a laser range sensor is used to detect the movement of a leaf and therefore the radius of the intake area. Due to the hysteresis, an inherent nonlinear phenomenon associated with SMAs, a nonlinear robust controller is used to control the SMA actuators. The control design uses the sliding-mode approach and can compensate the nonlinearities associated with the SMA actuator. A proof-of-concept model is fabricated and its feedback control experiments show that the intake area can be precisely controlled using the SMA wire actuator and has the ability to reduce the area up to 25%. The experiments demonstrate the feasibility of engine intake area control using an SMA wire actuator under the proposed design.

Chewing Lice of Swan Geese (Anser cygnoides): New Host-Parasite Associations

  • Choi, Chang-Yong;Takekawa, John Y.;Prosser, Diann J.;Smith, Lacy M.;Ely, Craig R.;Fox, Anthony D.;Cao, Lei;Wang, Xin;Batbayar, Nyambayar;Natsagdorj, Tseveenmayadag;Xiao, Xiangming
    • Parasites, Hosts and Diseases
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    • v.54 no.5
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    • pp.685-691
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    • 2016
  • Chewing lice (Phthiraptera) that parasitize the globally threatened swan goose Anser cygnoides have been long recognized since the early 19th century, but those records were probably biased towards sampling of captive or domestic geese due to the small population size and limited distribution of its wild hosts. To better understand the lice species parasitizing swan geese that are endemic to East Asia, we collected chewing lice from 14 wild geese caught at 3 lakes in northeastern Mongolia. The lice were morphologically identified as 16 Trinoton anserinum (Fabricius, 1805), 11 Ornithobius domesticus Arnold, 2005, and 1 Anaticola anseris (Linnaeus, 1758). These species are known from other geese and swans, but all of them were new to the swan goose. This result also indicates no overlap in lice species between older records and our findings from wild birds. Thus, ectoparasites collected from domestic or captive animals may provide biased information on the occurrence, prevalence, host selection, and host-ectoparasite interactions from those on wild hosts.

Effects of environmental enrichment on behaviour, physiology and performance of pigs - A review

  • Mkwanazi, Mbusiseni Vusumuzi;Ncobela, Cypril Ndumiso;Kanengoni, Arnold Tapera;Chimonyo, Michael
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.1
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    • pp.1-13
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    • 2019
  • This paper aims to critically analyse and synthesise existing knowledge concerning the use of environmental enrichment and its effect on behavior, physiology and performance of pigs housed in intensive production systems. The objective is also to provide clarity as to what constitutes successful enrichment and recommend when and how enrichment should be used. Environmental enrichment is usually understood as an attempt to improve animal welfare and to a lesser extent, performance. Common enrichment objects used are straw bedding, suspended ropes and wood shavings, toys, rubber tubings, colored plastic keys, table tennis balls, chains and strings. These substrates need to be chewable, deformable, destructible and ingestible. For enrichment to be successful four goals are essential. Firstly, enrichment should increase the number and range of normal behaviors; secondly, it should prevent the phenomenon of anomalous behaviors or reduce their frequency; thirdly, it should increase positive use of the environment such as space and fourthly it should increase the ability of the animals to deal with behavioral and physiological challenges. The performance, behavior and physiology of pigs in enriched environments is similar or in some cases slightly better when compared with barren environments. In studies where there was no improvement, it should be borne in mind that enriching the environment may not always be practical and yield positive results due to factors such as type of enrichment substrates, duration of provision and type of enrichment used. The review also identifies possible areas that still need further research, especially in understanding the role of enrichment, novelty, breed differences and other enrichment alternatives.

Interaction effects of pen environment and sex on behavior, skin lesions and physiology of Windsnyer pigs

  • Mkwanazi, Mbusiseni Vusumuzi;Kanengoni, Arnold Tapera;Chimonyo, Michael
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.3
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    • pp.452-458
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    • 2019
  • Objective: The study was carried to determine the interaction effects of pen enrichment and sex on behavioral activities, skin lesions and physiology of Windsnyer pigs. Methods: Forty-eight growing Windsnyer pigs of both sex, with an average initial body weight of 21.6 (${\pm}9.01$) kg were used. Four pigs were randomly assigned to either enriched or barren pens at a stocking density of $0.35m^2/pig$. Enriched pens contained 2 L bottles filled with stones and suspended at head level on ropes stretching across the pens. In addition, two plastic balls (90 mm in diameter) and 500 mL bottles (235 mm long) were placed on the floor of each enriched pen. Results: Pigs in barren environments had higher heart rates (p<0.001) than those in enriched pens. There was an interaction of pen environment and sex on rectal temperature (p<0.001). Females in enriched pens had higher rectal temperatures (p<0.05) than females in barren pens. There was no interaction of pen environment and sex on time spent eating and drinking (p>0.05). Time spent bullying was influenced (p<0.05) by pen environment and sex. Female pigs in barren environment spent more time on bullying than females in enriched pens. There was an interaction of pen environment and sex on time spent lying down and walking (p<0.05). Female pigs in enriched pens spent more time lying down than females in barren pens. Males in barren pens spent more time walking than males in enriched pens while no effect of pen environment was observed in females. There was an interaction of pen environment and sex on the number of skin lesions in the head, neck and shoulder region and other parts of the body (p<0.05). Conclusion: It was concluded that pen enrichment reduced the number of skin lesions and anti-social behaviors, especially for female pigs. There is a need, therefore of housing indigenous pigs under confinement.

A comparison of Echium, fish, palm, soya, and linseed oil supplementation on pork quality

  • Barbara Elizabeth van Wyngaard;Arno Hugo;Phillip Evert Strydom;Foch-Henri de Witt;Carolina Henritta Pohl;Arnold Tapera Kanengoni
    • Animal Bioscience
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    • v.36 no.9
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    • pp.1414-1425
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    • 2023
  • Objective: Long chain n-3 polyunsaturated fatty acids (PUFA) exert positive effects on human health. The long chain n-3 PUFA of pork can be increased by adding fish oil to the diet. Due to the cost and availability of fish oil an alternative source must be found. Methods: This study evaluated the effect of five dietary oils on meat quality, fatty acid composition and lipid stability. The five diets contained 1% palm oil (Control), 1% soya oil, 1% linseed oil, 1% fish oil, and 1% Echium oil, respectively. The trial consisted of 60 gilts, randomly allocated to five groups. Results: All color parameters, extractable fat content, fat free dry matter, and moisture content of the m. longissimus muscle were unaffected by dietary treatment. Consumers and a trained sensory panel could not detect a difference between the control samples and the Echium oil sample during sensory analysis. Samples containing higher levels of PUFA (soya, linseed, fish, and Echium oil) had higher levels of primary and secondary lipid oxidation products after refrigerated and frozen storage. However, these values were still well below the threshold value where off flavors can be detected. The Echium oil treatment had significantly higher levels of long chain PUFA than the linseed oil treatment, but it was still significantly lower than that of the fish oil treatment. Conclusion: Echium oil supplementation did not increase the levels of n-3 to the same extent as fish oil did. The result did however suggest that Echium oil can be used in pig diets to improve muscle long chain n-3 fatty acid content without any adverse effects on meat quality when compared to linseed, soya, and palm oil.

Reliability and responsiveness of Equivital Lifemonitor and photoplethysmography based wristwatch for the assessment of physiological parameters during a simulated fatigue task

  • Anwer, Shahnawaz;Li, Heng;Umer, Waleed;Antwi-Afari, Maxwell Fordjour;Wong, Arnold YL
    • International conference on construction engineering and project management
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    • 2020.12a
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    • pp.257-264
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    • 2020
  • Objective: To investigate test-retest reliability and responsiveness of Equivital Lifemonitor and photoplethysmography based wristwatch tools in assessing physiological parameters during a simulated fatigue task. Methods: Ten university students (Mean age, 30.6 ± 1.7 years) participated in this pilot study. Participants were asked to perform a 30-minute of a simulated fatigue task in an experimental setup in a lab. The physiological parameters (e.g., heart rate, heart rate variability, respiratory rate, electrodermal activity, and skin temperature) were measured at baseline and immediately after the fatigue task. An intraclass correlation coefficient (ICC2,1) was used to evaluate the test-retest reliability of each tool in assessing physiological measures. In addition, the responsiveness of each tool to measure changes from baseline to posttest was calculated using a standardized response mean. Results: The Equivital Lifemonitor has shown good to excellent test-retest reliability for the assessment of heart rate (ICC, 0.97), heart rate variability (ICC, 0.86), respiratory rate (ICC, 0.77), and local skin temperature (ICC, 0.76). However, photoplethysmography based wristwatch showed moderate to good test-retest reliability for the assessment of heart rate (ICC, 0.71), heart rate variability (ICC, 0.73), electrodermal activity (ICC, 0.80), and skin temperature (ICC, 0.72). A large standardized response mean (>0.8) indicates that both tools can capture the changes in heart rate, heart rate variability, respiratory rate, skin temperature, and electrodermal activity after a 30-minute of fatigue task. Conclusions: The Equivital Lifemonitor and photoplethysmography based wristwatch devices are reliable in measuring physiological parameters after the fatigue task. Additionally, both devices can capture the fatigue response after a simulated construction task. Future field studies with a larger sample should investigate the sensitivity and validity of these tools in measuring physiological parameters for fatigue assessment at construction sites.

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The Effect of Individual Differences in Need for Affective and Cognitive on Health Advice in Virtual Reality (감성 욕구와 인지 욕구의 개인차가 가상현실의 건강 조언에 미치는 영향)

  • Yu, Sanghyeong;Jung, Yujin;Han, Kwanghee
    • Science of Emotion and Sensibility
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    • v.22 no.3
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    • pp.77-90
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    • 2019
  • In this study, we investigated which message provider is effective in a virtual reality (VR) environment for individuals with different needs with regard to affect (need for affect [NFA]) and cognition (need for cognition [NFC]). According to Haddock et al (2008), individuals with high NFA were more influenced to change their behavior by the emotional aspects of a message, whereas individuals with high NFC were more influenced by the cognitive aspects of the same message. We hypothesized that individual differences in needs could affect not only receipt of the message but also the acceptability of the message provider. For example, someone with high NFA might accept messages more easily from an acquaintance than from experts. In the VR environment, the appearance of the message provider could be manipulated in a way that makes him or her more familiar to the person receiving the message. Accordingly, in order to promote the effectiveness of message providers in a VR environment according to the individual difference in needs, we measured the level of the preference and self-efficacy according to needs (NFA or NFC), type of message provider (expert, significant other, or other), and VR device (text or VR). Contrary to what we expected, the results showed that there was no matching effect between the needs and the message provider. However, we found that level of preference and self-efficacy were significantly high when a VR device was worn only by participants with high NFA. This result suggests that a VR environment is more suitable for providing health advice to people with high NFA. In addition, the novelty of this study is that we tried to find the tailored message provider on health advice in VR environment and it is in the early stage of the research.

Nutritional Studies on Production of Antibacterial Activity by the Zebra Mussel Antagonist, Pseudomonas fluorescens CL0145A

  • Polanski-Cordovano, Grace;Romano, Lea;Marotta, Lauren L.C.;Jacob, Serena;Hoo, Jennifer Soo;Tartaglia, Elena;Asokan, Deepa;Kar, Simkie;Demain, Arnold L.
    • Journal of Microbiology and Biotechnology
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    • v.23 no.5
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    • pp.656-660
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    • 2013
  • Pseudomonas fluorescens strain CL0145A was discovered at the New York State Museum Field Research Laboratory as an effective agent against the environmentally destructive zebra mussel, which has contaminated US waters. Dried cells of the microbe are being commercialized as an environmentally friendly solution to the problem. We found that antibiotic activity against the Gram-positive bacterium Bacillus subtilis is produced and excreted by this strain. We have carried out studies to optimize production of the antibiotic. Studies were begun in a complex corn meal medium. Activity was found in both cells and culture supernates and was maximal after one day of fermentation. Static fermentation conditions were found to be superior to shaken culture. Production of extracellular antibiotic in complex medium was found to be dependent on the content of sucrose and enzyme-hydrolyzed casein. Indeed, production was greater in sucrose plus enzyme-hydrolyzed casein than in the complex medium. Of a large number of carbon sources studied as improvements over sucrose, the best was glycerol. An examination of nitrogen sources showed that production was improved by replacement of enzyme-hydrolyzed casein with soy hydrolysates. Production in the simple glycerol-Hy-Soy medium was not improved by addition of an inorganic salt mixture or by complex nitrogen sources, with the exception of malt extract. In an attempt to keep the medium more defined, we studied the effect of amino acids and vitamins as replacements for malt extract. Of 21 amino acids and 7 vitamins, we found tryptophan, glutamine, biotin, and riboflavin to be stimulatory. The final medium contained glycerol, Hy-Soy, tryptophan, glutamine, biotin, and riboflavin.

Insecticide Resistance to Small Brown Planthopper (Laodelphax striatellus Fallen) (1). Local Variabilities in Susceptibility of Small Brown Planthopper to Malathion and NAC (애멸구의 약제저항성에 관한 연구(I). Malathion 및 NAC에 대한 애멸구감수성의 지역적 차이)

  • Choi Seung Yoon;Song Yoo Han;Park Jung Soo
    • Korean journal of applied entomology
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    • v.14 no.2 s.23
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    • pp.53-58
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    • 1975
  • The local variabilities of resistance to Malathion and NAC (Sevin) were studied during 1973 with the strains of small brown planthopper (Laodelphax striatellus Fallen) collected from Jinjoo, Sunsan, Milyang, Kwangjoo and Iri districts of southern part of Korea. The susceptible lab strain used for this study has been reared successively in the laboratory without exposure to any insecticide since 1970. The insecticides were applied topically in acetone to the thoracic sternum of the adult insects. $LD_{50}$ values of Malathion to the insect were varied with the locality of the planthoppers. Relatively high levels of resistance to Malathion were observed in the strains of Jinjoo and Suntan; showing 27.7 times in female and 24.9 times in male for Jinjoo stram and 18.4 times in female and 13.8 times in male for Sunsan strain as compared with the susceptible lab strain, and in other strains of Milyang, Kwangjoo and Iri the levels of resistance to Malathion were still less than 5 times. However, there was no any specific difference among the strains in susceptibility to NAC. The malathion-resistant strain of the small brown planthopper seemed to be still localized in some regions of· Korea. The susceptibility of the planthoppers to Malathion was varied with the sex; $LD_{50}$ values based on the individual (ug/insect) were higher in female than in male, while the values based on the body weight (ug/g) conversely higher in male than in female.

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A Study on Parental Beliefs, Value of Children and Filial Obligation of the unmarried (미혼 성인의 자녀양육신념 양상과 자녀에 대한 가치 및 부모 부양의무감간의 관계)

  • Cho, Bok Hee;Jung, Min Ja;Kim, Yeon Ha
    • Korean Journal of Childcare and Education
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    • v.3 no.2
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    • pp.22-47
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    • 2007
  • The purpose of this study was to examine whether parental beliefs, value of children, and filial obligation were related. The subjects were 748 students(male 323, female 425) who were currently enrolled at university located in Seoul. The instruments used for this study were Filial Obligation Scale(Cho, 2002), Parenting Beliefs Questionnaire, and Value of Children by Arnold et al.(1975, 2001). Data were analyzed using descriptive statistics, t-test, ANOVA, and Pearson's correlations by SPSS PC Program. The results showed that university students generally demonstrated a higher level of individual-oriented beliefs than relation-oriented beliefs on parental beliefs. With regard to parental beliefs, family relation-oriented beliefs was relatively low in comparison with independence/autonomy-oriented beliefs, happiness-oriented beliefs, and cognition/knowledge-oriented beliefs. In addition, emotional value of children was relatively high in comparison with instrumental value of children. Also, male university students possessed a higher level of filial obligation. the level of cohabitation experience with their parents played a significant role in affecting the level of filial obligation. Unsurprisingly, a higher relation-oriented parental beliefs and emotional value of children demonstrated a higher level of filial obligation. There were also positive relationships between emotional value, instrumental value, and filial obligation. Hence, this study suggests that a practical, functional training services and resources for future parents must be ensued.

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