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Morphological Changes of the Embryo and First Zoea Larvae of Snow Crab, Chionoecetes opilio (O. Fabricius) (대게 Chionoecetes opilio (O. Fabricius)의 난발생 및 부화 유생의 형태)

  • 임영수;이복규;이종관;허성범
    • Journal of Aquaculture
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    • v.11 no.3
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    • pp.337-344
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    • 1998
  • This paper documented mophological changes of embryonic development and first zoea larvae of snow crab, Chinoecetes opilio. Female crabs were sampled by the Danish seine fishery at the depth about 200m in Sep. 1997 in the eastern coast of Korea. Female with newly berried eggs was reared at the water temperature of 5$^{\circ}C$ till the time of hatching. The results obtained are as follwos. Embryonic development : According to morphogenesis of fertilized eggs, the developemental process of the embryo was classified into the following seven stages : First stage (cleavage and blastula stage, 24 days) Second stage (gastrula stage, 72 days) Third stage (nauplius stage, 22 days) Fourth stage (metanauplius stage, 57days) Fifth stage (stage of a pigmentary deposit in the compound eye, 30 days) sixth stage (chromatophore appearance stage in maxillipede, 56 days) Seventh stage (hatching stage, 36 days) Larvae hatched as prezoeas and they molted to first zoea in about an hour. The first zoea is 4.6 to 5.1mm in length, 3.2~3.6mm in width. The abdomen consists of five segments and a bifurcate telson.

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An Evolutionary Concept Analysis of Helicopter Parenting (헬리콥터 양육에 대한 진화론적 개념분석)

  • Lee, Yong-Wha;Kim, Ji-Hyun;Yim, So-Youn;Chae, Myung-Ock;Lee, Hye-Rim;Oh, Jina
    • Child Health Nursing Research
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    • v.20 no.4
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    • pp.237-246
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    • 2014
  • Purpose: Helicopter parenting is an emerging concept as a way of rearing adolescents and adult children. However, helicopter parenting from a nursing perspective has not been elucidated. Therefore, we undertook a concept analysis to understand the attributes, antecedents and consequences of helicopter parenting in the context of nursing. Methods: Using Rodgers' evolutionary concept analysis, we analyzed literature on helicopter parenting to discover critical attributes, antecedents, and consequences of this phenomenon. Data were collected from seven electronic search engines. Twelve studies matching inclusion criteria were reviewed. Results: Three core attributes of helicopter parenting were hovering, highly deep involvement, and proxy decision making. The antecedents and consequences were retrieved from three important domains including social, parent, and child aspects. Surrogate terms were black hawk, hummingbird, and hovercraft parenting, and related terms were stealth fighter and Kamikaze parenting. Conclusion: Based on the results of this study, helicopter parenting has both positive and negative effects on both children and parents. To enhance the positive effects, measurement tools for helicopter parenting and nursing interventions on parenting need to be developed.

The Antimutagenic and Anticancer Effect of Taxus cuspidata Extracts (주목 추출물의 발암 억제효과 및 암세포에 미치는 영향)

  • 황병호;조국난;최근표;정성원;김은정;함승시
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.25 no.6
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    • pp.1062-1068
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    • 1996
  • This study was Performed to determine the effects of antimutagenicity and anticancer of Taxus cuspidata produced in Korea. Extracts of Taxus cuspidata were obtained from leaves, barks and roots. All the samples tested had no effects on the mutagenicity by Ames test using Salmonella typhimurium TA98 and TA100 or rec-assay using Bacillus subtilis Hl7 and M45 strains. However the treatment of 50$\mu\textrm{g}$/plate of Taxus cuspidata extracts showed strong antimutagenicity with 98% inhibition against TA100 induced by MNNG and with 98% inhibition against TA98 and TA100 induced by 4NQO whereas 73~89% and 16~60% antimutagenic effect were shown against both strain induced by Trp-P-1 and $Benzo(\alpha)pyrene,$ respectively. The treatment of $0.5$\mu\textrm{g}$/{\mu}\ell$ root extracts had the highest cytotoxicity with 90% against liver cancer cell, Hep 3B, followed by bark extracts(87%) and leave extracts(72%), whereas $0.5$\mu\textrm{g}$/{\mu}\ell$ treatment of Taxus cuspidata extract had only 22~36% cytotoxicity on human normal liver cell WRL 68.

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COMPARATIVE STUDY OF CHARACTERISTICS IN RORSCHACH RESPONSE AND SANDPLAY BETWEEN ADHD AND NORMAL CHILDREN (ADHD 아동과 정상아동의 Rorschach반응 및 모래놀이치료 내용 비교)

  • Cho Sun-Mi;Choi Ji-Won
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.17 no.1
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    • pp.51-59
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    • 2006
  • Objectives : Present study compared the characteristics in Rorschach responses and Sandplay between ADHD and normal children group. Method : ADHD (excluded inattention type & emotional problem) group and normal group was composed of 10 children respectively. All of them were controlled by Intelligence Quotation. Rorschach responses were scored by Exner system and compared by t-test. For sandplay work, the time was measured and photo was taken. Results : 1) ADHD group showed that the reaction time in Rorschach was significantly fast and they easily failed to recall the responses. The statical significances are 3r+ (2)/R, X-%, Xu%, (2), AG, Afr, SCZI, Wsum 6, FD, Zd, Blends, a. 2) ADHD group showed that the reaction time in Sandplay was significantly fast, they used low materials (total numbers of toy, vehicles) and the work was less coordinated. Conclusion : This results suggest that ADHD children are apt to react, think and coordinate impulsively. Also, Sandplay could be used fur diagnostic method as Rorschach test.

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Measurement and Analysis of P2P Traffic in Campus Networks Under Firewall (방화벽이 존재하는 캠퍼스 망에서의 P2P 트래픽 측정 및 분석)

  • Lee, Young-Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.11B
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    • pp.750-757
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    • 2005
  • This paper reports on the study of P2P traffic behaviors in a high-speed campus network under a simple firewall which drops packets with default port numbers for the well-blown P2P applications. Among several ways of detecting P2P traffic, the easiest method is to filter out packets with the default port number of each P2P application. After deploying the port-based firewall against P2P-traffic, it is expected that the amount of P2P traffic will be decreased. However, during the eight-month measurement period, three new commercial P2P applications have been identified and their traffic usages have reached up to $30/5.6\%$ of the total outbound/inbound traffic volumes at the end of the measurement period. In addition, the most famous P2P application, eDonkey, has adapted and has escaped detection through port hopping. The measurement result shows that the amount of eDonkey traffic is around $6.7/4.0\%$ of the total outbound/inbound traffic volume. From the measurement results, it is observed that the port-based firewall is not effective to limit the usage of P2P applications and that the P2P traffic is steadily growing due to not only the evolution of existing P2P applications such as port hopping but also appearances of new P2P applications.

Performance Evaluation of Recycled Aggregate Concrete Made of Recycled Aggregate Modified by Carbonation (탄산화 개질 순환 골재를 사용한 순환 골재 콘크리트의 성능 평가)

  • Ha, Jung-Soo;Shin, Jin-Hak;Chung, Lan;Kim, Han-Sic
    • Journal of the Korea Concrete Institute
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    • v.28 no.4
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    • pp.445-454
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    • 2016
  • With the increase of decrepit facilities, construction waste increased to a certain level and now the increase is more or less stabilized. Yet construction waste still constitutes the largest portion of the overall wastes. Also, it is inevitable to spend a huge amount of the national budget due to the aggravating shortage of aggregate caused by prohibition on collection of natural aggregates as well as due to the damage to the land and environment caused by development of the sources of aggregates. As a countermeasure to the situation, the Ministry of Land, Infrastructure and Transport promulgated the quality standard for recycled aggregate to manage the usage of recycled aggregate according to its quality. But use of recycled aggregate for the purpose of high added value still remains nominal. Therefore, this research aims to study the applicability of recycled aggregate concrete as structural concrete by evaluating the quality improvement effects and the performance of the recycled aggregate concrete including recycled fine aggregate and recycled coarse aggregate that have undergone carbonation for 4 days and 14 days respectively in the condition of 60% RH, 20% $CO_2$ and $20^{\circ}C$ temperature, suggested for carbonation modifying from the advance research. The result shows carbonation modify contributed to quality improvement with 0.91% decrease in absorption rate for recycled fine aggregate and 0.7% decrease in absorption rate for recycled coarse aggregate. The physical properties and durability of the recycled aggregate made of aggregate modified by carbonation showed results similar to general concrete, which confirmed the possibility of applying the recycled aggregate made of recycled aggregate modified by carbonation to structural concrete.

Vehicle Emergency Lamp Fuzzy Control Systems Using The GPS (GPS를 이용한 자동차 비상등 작동 장치)

  • Kwon, Yunjung;Nam, Sangyep
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.6
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    • pp.276-281
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    • 2014
  • Necessities of a traffic means work a car in the modern society human to an usability of a life is enjoying. On the other hand, the damage by traffic accident increment the human quotient worked as we were in proportion to the vehicle which increased. Passing an examination moves necessarily on an obstacle to suddenly appear at the fronts if a car travels and the vehicles which stopped suddenly. Dynamic passing an examination about an obstacle turn on Vehicle Emergency Lamp to by hand when is unhurried, and can turn off, but to appear urgently dynamic passing an examination in time human is instinctive, but cannot inform an emergency to a back vehicle, and a rear-end collision occurs. A car we synthesize a speed of a vehicle, and this unit analyzes as we use GPS, and to drive runs Vehicle Emergency Lamp to automatic in the situations that shall turn on emergencies etc. If a speed of a vehicle continuously slows down in too high-speed driving or low-speed driving, or we are stopped, Vehicle Emergency Lamp is always turned on. It was built if we rise again as clearing itself from risk, and a speed of a vehicle judges, and we turn off Vehicle Emergency Lamp to automatic. It runs till rear-end collision sensor operates, and by hand reset does Vehicle Emergency Lamp a driving vehicle collides from behind to a back vehicle or when a driving vehicle was overthrown. It is shortened very much to the chain rear-end collision traffic accident that is a traffic accident of large size if we use this unit. And we did authentication through the experiment which a driver was helpful to unnecessary operation and a relaxed safe driving during drivings.

Egg Development and Early Life History of the Endangered Species Gobiobotia macrocephala (Cyprinidae) (멸종위기 어류 꾸구리 Gobiobotia macrocephala의 난발생 및 초기생활사)

  • Ko, Myeong-Hun;Kim, Woo-Joong;Park, Sang-Yong;Bang, In-Chul
    • Korean Journal of Ichthyology
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    • v.23 no.3
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    • pp.198-205
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    • 2011
  • Early life history of the endangered species, Gobiobotia macrocephala was investigated to provide baseline data for biological characteristics and recovery. Adult fish were sampled by spoon net at Hongcheon-gun, Gangwon-do, Korea in April to June 2010. The female's eggs were obtained by injecting Ovaprim and fertilized by dry method in the laboratory. The mature eggs were slightly adhesive and transparent with greyish and average 0.89${\pm}$0.04mm in diameter. The hatching of the embryo took place in about 107 hours after fertilization under water temperature of 23$^{\circ}C$ and newly hatched larvae were average 4.6${\pm}$0.16mm in total length. At 4 days after hatching, they were average 6.1${\pm}$0.20mm in total length and their yolk sacs were completely absorbed. From 15 days after hatching, they entered the juvenile stage and reached at 8.6${\pm}$0.67mm in total length. At the 100 days after hatching, their band patterns and external form were similar to those of adults, and they averaged 31.5${\pm}$3.32mm in total length.

Studies on Seed Production of Rainbow Trout, Oncorhynchus mykiss - Hatching rate and early stage performance of USA strain rainbow trout, Oncorhynchus mykiss - (무지개송어, Oncorhynchus mykiss의 종묘생산에 관한 연구 - 미국산 무지개송어의 부화 및 자치어 성장 -)

  • Baik, Kook-Ki;Choi, Young-Hee;Lee, Joong-Chul;Park, In-Sik;Kim, Young-Kil;Kim, Doo-Youn;Lee, Chae-Sung
    • Journal of Aquaculture
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    • v.20 no.2
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    • pp.85-89
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    • 2007
  • This study examined the hatching rate of eyed-eggs and growth of fingerlings of USA strain rainbow trout, Oncorhynchus mykiss, which were transplanted on Nov. 17, 2005 from the USA for improvement of breeding. The diameter and weight of eyed-eggs were $4.95{\pm}0.34\;mm$ and $0.07{\pm}0.003\;g$, respectively. The eyed-eggs were hatched in 8 days later and hatching rates were $77.3{\sim}98.6%$. After 56 days from hatching, the fingerlings grew to $4.0{\pm}0.7$ cm and 0.62 g in total length and body weight, respectively. The relationships between total length (TL) and elapsed days (ED) were expressed as TL=0.0366ED+1.8645 ($r^2=0.928$, n=350). The relationships between body weight (BW) and elapsed days (ED) were expressed as following; $BW=0.0638e^{0.0408ED}\;(r^2=0.9917,\;n=350)$. And survival of rainbow trout was $64.5{\pm}1.3%$ in 56 days after hatching.

Development, Reproduction and Longevity of Predator Orius sauteri Poppius(Hemiptera: Anthocoridae) when Reared on Three Different Preys (애꽃노린재(Orius sauteri) 발육,성충수명 및 산란에 미치는 먹이의 영향)

  • 백채훈;황창연;이건휘;김두호;최만영;나승용;김상수
    • Korean journal of applied entomology
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    • v.42 no.1
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    • pp.35-41
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    • 2003
  • Anthocorid bugs (Orius spp.) are known as polyphagous predators preying on thrips, aphids, mites, eggs of small insects and whiteflies. This study was conducted to investigate the nym-phal development, survival rate, longevity of Orius sauteri adult and oviposition, when nymphs of western flower thrips (Frankliniella occidentalis) and cotton aphid (Aphis gossypii), and eggs of two-spotted spider mite (Tetranychus uritcae) were fed as diets. Nymphal development of female/male O. sauferi fed with F. occidentalis, A. gossypii and T urticae took 12.2/12.8, 13.0/l3.2, and 17.9/17.8 days at 27$^{\circ}C$, respectively, Survival rates during nymphal development were 96.4, 78.4, 73.8%, longevity of female/male adults were 55.9/51.0, 30.2/30.8, and 25.8/25.1 days, and daily oviposition were 5.6, 4.1, and 1.9 eggs, respectively. Oviposition of O. sauteri fed with F. occidentalis usually began 3-4 days after emergence at 27$^{\circ}C$, and reached at its peak of 7-8 eggs female day 20-40 days after emergence.