• Title/Summary/Keyword: 성장과 발달

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A Fundamental Study for Design of Electric Energy Harvesting Device using PZT on the Road (도로용 압전발전체 시험모듈 설계를 위한 기초 실험 연구)

  • Lee, Jae-Jun;Ryu, Seung-Ki;Moon, Hak-Yong;Kwon, Soo-Ahn
    • International Journal of Highway Engineering
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    • v.13 no.4
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    • pp.159-166
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    • 2011
  • Green house gas emissions are increasing as development of the industrial economy of the international community. Many countries in the world are endeavoring to reduce green house gas emissions under severe climate change. In order to protect grobal warming, government is trying to reduce green gas emissions under "Low Carbon Green Growth Policy" and investing climiate-firendly industries such as renewable energy harvesting. Renewable energy has been rapidly developing as a result of investment for development technology of using natural energy such as solar, wind, tidal, etc. There are lots of waste energy in the road space. However, nobody is not interested in waste energy from the road space. This paper present a fundamentally experimental study of energy harvesting technique to use waste energy in the road. The waste energy in the road is covered a pressure and impact of vehicles on the road, the radiant heat from asphalt pavement, road noise and vibration etc. In this study, an energy harvesting device using piezoelectric element is proposed and various tests are conducted to investigate a characteristic of this device as function of impact loading based on piezoelectric effect behavior. This paper shows the energy harvesting results of the device using domestic piezoelectirc element as a function of impact load size and pavement types.

The Factors That Cause Customer Satisfaction in Private Security Service: Comparison between Corporate Clients and Individual Clients (민간경비 서비스의 고객 만족도에 영향을 미치는 요인: 사업자고객과 개인고객의 비교)

  • Shin, So-Ra;Cho, Youn-Oh
    • Korean Security Journal
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    • no.34
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    • pp.161-184
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    • 2013
  • The purpose of this research is to achieve qualitative growth for private security industry as a sector of service industry to attract clients and promote the growth of the private security industry by analyzing the factors which influence the customer's service satisfaction in using the private security services. A regression analysis was conducted to determine the factors which influences the satisfaction of private security service to ultimately achieve the research purpose. In the regression analysis, the difference between corporate clients and individual clients were analyzed for the sake of providing better security services and marketing applications. As a result, the factors that influences the satisfaction of the categorized groups were very clearly signified. Both individual and corporate clients showed increase in satisfaction rate when the fear of crime decreased. This result implies that the private security firms must possess segmented strategies as well as strategies to lower the fear factors of clients. There were no differences in all satisfaction-influencing factors when the fear reduction variable was exempted among both corporate and individual clients in usage satisfaction. This result shows that clients demand varies according to the client and the security firms must react to these demands by the clients. Although private security industry possess very clear publicity, it is a profit generating industry sector therefore, like other service industry, the private security services must implement strategies to keep up with the paradigm. If the satisfaction determinants from the research results are grafted into strategies such relationship marketing and target market selection, higher service satisfaction can be achieved from the clients.

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Artificial Spawning, Larval and Spat Developments of the Bay Scallop, Argopecten irradians (해만가리비, Argopecten irradians의 인공산란과 유생 및 치패의 발생)

  • Oh, Bong-Se;Jung, Choon-Goo;Kim, Sook-Yang
    • The Korean Journal of Malacology
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    • v.19 no.1
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    • pp.19-24
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    • 2003
  • Artificial spawning, larval and spat developments of the bay scallop, Argopecten irradians, which was transplanted from China on 16 August 1996, were investigated monthly until August 1997 in the Deukyang Bay, Jangheung-gun, Jeollanam-do, Korea. Sufficient amount of cultured microalgae supplemented seawater were supplied as food (6 kinds of phytoplankton) for fully grown adult individuals at 17.1-23.2$^{\circ}C$ for 44 days. A total of 45,320,000 eggs were spawned by way of 2 times of artificial spawning inductions such as exposure stimulus to the air and thermal shock (with water temperature) on 29 January and 31 January in 1997. Artificially fertilized eggs were developed to D-shaped larvae (77.5 ${\times}\;63.8\;{\mu}m)$ and metamorphosed to larvae (191.8 ${\times}\;181.2\;{\mu}m)$ 181.2 m) in the attached larval stage on the collectors. A total of 110,000 spats (average 3.04 mm in shell length) were produced at 22.8-26.3$^{\circ}C$ and 31.0-34.4 psu in the indoor rearing tank from 14 February through 7 May in 1997. In case of Argopecten irradians, if the attached larvae in the attachment stage are detached from the collector, they could not live. Accordingly, it is assumed that survival (%) of the attached larvae of A. irridians showed very low because of weak power attached to the collector due to the small number of the byssuses of the attached larva, not the short attachment period by the byssus as seen in other scallops such as Argopecten balloti.

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Development of nature friendly characters for infants and toddlers (영유아를 대상으로 한 자연친화적 캐릭터 개발 연구)

  • Joo, Eun-Ryeong;Chung, Jean-Hun
    • Journal of Digital Convergence
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    • v.16 no.3
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    • pp.415-422
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    • 2018
  • The purpose of this paper is to show development examples of nature-friendly characters and to play a guide role for various nature-friendly characters to appear by presenting nature-friendly characters setting in Korea. Three famous examples of nature-friendly characters in foreign countries and the influence of nature on infants and young children will be examined with reference to previously published papers and published books. I have confirmed that nature harmony positively affects emotions and life respect of infants and young children, the characteristics of nature-friendly characters are 1. The characters are drawn based on nature environment as background. 2. They have been beloved for story of nature conservation and love for nature, and playing in nature environment. As story setting, I suggested 1. A story of forest experience with friends 2. A story of nature observation and exploration such as playing, exploration, and explanation 3. A drawing of Korea nature environment, including grass, flower, tree, insect, etc. 4. An educational and philosophical story of life respect, nature conservation, and love for nature.

Properties of Thick Films Prepared with $V_2O_5$-doped Ferrite Pastes ($V_2O_5$ 도핑한 페라이트 페이스트 후막 특성)

  • 제해준;김병국;박재환;박재관
    • Korean Journal of Crystallography
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    • v.12 no.2
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    • pp.70-75
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    • 2001
  • The purpose of this study is to investigate the effect of V₂O/sub 5/ addition on physical and magnetic properties of NiCuZn ferrite for multi-layer chip inductors. NiCuZn ferrite pastes doped with 0, 0.1, 0.3 and 0.5 wt% V₂O/sub 5/ were prepared and samples of ferrite sheets were prepared by the screen printing method. They were sintered at 870, 880, 890 and 900℃, and then their physical and magnetic properties were analyzed. After sintering at 870℃, the sintered density of the ferrite sheet doped with 0.5wt% V₂O/sub 5/ showed the highest value to 5.08g/cm³due to the best densification by the liquid phase sintering, while the microstructures of ferrite sheets doped with 0.1 and 0.3 wt% V₂O/sub 5/ showed and inhibited grain growth. Irrespective of the sintering temperature, the initial permeability of ferrite sheet doped with 0.5 wt% V₂O/sub 5/ was highest and after sintering beyond 880℃, the quality factor of 0.3 wt% V₂O/sub 5/-doped sample appeared to be highest.

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Dental Management in a Patient with Infantile Osteopetrosis : A Case Report with a 7-Year follow-up (유아기형 골화석증 환자의 치과적 관리 : 7년간의 경과 관찰)

  • Cheon, Minkyoung;Yang, Sunmi;Kim, Jaehwan;Choi, Namki;Kim, Seonmi
    • Journal of the korean academy of Pediatric Dentistry
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    • v.45 no.2
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    • pp.257-264
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    • 2018
  • Osteopetrosis is characterized by impaired osteoclast function and increased bone density. Infantile osteopetrosis is a severe form of the disease and has characteristics such as diffusely sclerotic skeleton, pancytopenia, cranial nerve entrapment, infection susceptibility, and abnormal craniofacial appearance. Patients with infantile osteopetrosis often experience developmental delay, and may have a short life span. A 14-month-old girl with osteopetrosis presented to the department of pediatric dentistry. Incipient caries on deciduous incisors were observed. The patient revisited 4 years of age. Besides medical problems, oral complications such as growth retardation, narrow upper arch, crowding, dental caries, and abnormal tooth development were observed. After consultation with her pediatrician, dental treatments were performed on the deciduous molars under sedation after a prophylactic antibiotic injection. At a periodic follow-up, multiple deciduous teeth were treated and extracted, and oralrehabilitation with a removable partial denture was initiated. Patient with osteopetrosis are highly susceptible to infection because of their compromised immune system and problems associated with wound healing that lead to osteomyelitis or sepsis development. Active participation in dental care for sugar intake management and proper oral hygiene are obligatory.

A Comparative Study of Actuality of Elementary and Middle School Teachers' Perception on Cyber Home Learning System (사이버 가정학습체제에 대한 초중등 교사의 인식실태 비교연구)

  • Jung, Ju-Young;Kim, Hyang-Sook
    • Journal of The Korean Association of Information Education
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    • v.11 no.3
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    • pp.339-347
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    • 2007
  • Along with developments of information and communication technologies, internet has spread not only all over the society, but also our everyday life deeply. Recently, requirements for e-learning using internet in the educational aspect have a great influence on the changes of school educations. Cyber Home Learning System, in particular, has been implemented throughout the nation for the purpose of reducing private expenditure for education and promoting substantial improvements in quality of public education. However, there have been exposed many problems with respect to quality of operations and managements of the system comparing to its quantitative growth, and so, at this point in time, researcher conducted analysis of actuality of perceptions of both elementary and middle school teachers with a focus on the case of S System in K province. To test this, total 278 participants were sampled from the elementary schools (139 teachers) and the middle schools (139 teachers) located in K province and were asked to complete a survey and the results therefrom were analyzed accordingly. Results from the analyses revealed that elementary school teachers responded more positively than other respondents in the most areas, including supply of a variety of learning contents of S System, quality of contents, and providing for helps insomuch as to complement school works, etcetera. In addition, researcher has found out that, to make the system become all the more efficient, it shall be required to establish a strategy in order to induce students' interest in the system, as well as to construct infrastructure for facilitating the use of computer. And that there are also needs for continuous supports from both the school and the education authority concerned, and for method of flexible operation of curriculum.

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A Study on the Implementation of Intelligent Navigational Risk Assessment System for High-risk Vessel using IoT Sensor Gateway (IoT 센서연계장치를 이용한 고위험선박의 지능형 운항위험 분석 시스템 개발에 대한 연구)

  • Kim, Do-Yeon;Kim, Kil-Yong;Park, Gyei-Kark;Jeong, Jung-Sik
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.3
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    • pp.239-245
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    • 2016
  • In the midst of continuing international recession, the rate of maritime traffic and marine leisure markets are consistently growing. The Republic of Korea controls the marine traffic volume through vessel traffic centers and various other management facilities. Nevertheless, the continuous growth and complexity of marine traffic is resulting in repeated occurrences of marine accidents. Recovery is very difficult in cases of human injuries or deaths caused by marine accidents due to its nature, and the scale of marine accidents is also becoming greater with advanced ship building technologies. Passenger ships, oil tankers, and other such vessels used for specific purposes requires a more detailed navigational status surveillance and analysis, and numerous research has been conducted with an objective for monitoring such special purpose vessels. However, the data elements transmitted from the ocean to the shore station are limited to AIS and ARPA. We are implementing IoT ship sensor collection and a syncing system capable of transmitting various ship sensing data to the shore station, and also proposing a Safe Navigation Status Analysis System utilizing the collected data.

A Comparative Study on the Growth & Developmental Status of Premature and Full Term Infants During the First 3Years (미숙아와 정상아의 영유아기 성장발달상태 비교연구)

  • 박영애
    • Journal of Korean Academy of Nursing
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    • v.15 no.3
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    • pp.62-73
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    • 1985
  • The problems of growth & development due to maladjustment are gradually increasing while need for the treatment of children's diseases is decreasing. The level of developmental deficiency or delay correlates with neonatal birth weight and also with gestational age, i.e. degrees of prematurity. There-fore, developmental defects and potential risk factors' are more Common in premature infants than in full term infants. The purpose of this study is to define the difference in the growth at developmental status between premature and full term infants, and to define the relation between the developmental status and the physical growth during the first 3 years' Data were collected from January 10, 1985 to April 6, 1985 at 3 hospitals including St. Mary's Hospital, and through home visiting. The subjects of this study consisted of 79 Premature infants (G.A. <37wks. & B.W. <2.5kg) and 94 full term infants (G.A.≥37 wks. & B.W.≥2.5kg). The study method used was a questionnaire, anthropometric assessment and DDST for normative data of growth & development. The collected data were analyzed using descriptive statistics, chi-square test and t-test. The results of the study were as follows: Hypothesis: 1 : That the prematures will differ from the full term infants in the physical growth status during the first 3 years was partially supported (p<0.02) : The prematures reached up the full term infants in the physical growth status in the first 6 months. And, the first hypothesis was supported (P<0.01) : There are more cases which is below‘the Korean children's physical. growth standards’in prematures than in full term infants. Hypothesis 2 : That the prematures will differ from the full term infants in the developmental status during the first 3 years was supported (P< 0.001);‘Normal’developmental status due to DDST was less in prematures than in full term infants. And, the second hypothesis was Partially supported (P<0.02) : The developmental status of the pre-matures was different from that of the full term infants within the first 3 months by analysis of passed items in DDST, Hypothesis 3 : That the prematures' developmental status will relate to their physical growth during the first 3 years was supported (P<0.001) : If the prematures' developmental status is in delayed status, then, their physical growth status is also in delayed status. This study shows that the prematures differed significantly from the full term infants in the growth at developmental status during their infancy. This means that the nurse can foster the growth & development of the prematures by supportive care during their infancy. Further longitudinal study is needed to verify these findings for the environmental factors.

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3 Dimensional Changes of Bedrock Surface with Physical Modelling of Abrasion (마식에 의한 기반암면의 표면 변화에 대한 실험 연구)

  • Kim, Jong-Yeon
    • Journal of the Korean Geographical Society
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    • v.42 no.4
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    • pp.506-525
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    • 2007
  • Incision into bedrock channel is the primary control of landform evolution, but research into bedrock incision process stagnated for long time. Due to the scaling problem of the application of results from flume studies to bedrock channel, there is a strong need to simulate the bedrock incision process with more realistic models. As a part of investigation into controls of bedrock channel incision, three-dimensional changes of rock surface with abrasion was investigated with physical modelling. 18 rock plates were abraded with various sediment particle size and sediment load and abraded surfaces of the plates were scanned with high resolution 3-D scanner. To identify the spatial pattern of erosion of the rock plates, various methods were used. There was no synthetic or holistic method that showed all features of bedrock plate produced by abrasion, so each plate was analyzed using some available methods. Contour maps, shaded relief maps and profiles show that abrasion concentrated on the centre of plate (cross profile) and upstream and downstream edges (longitudinal profile) and eroded area extended inwards. It also found that the cracks and boundaries of forming materials easily eroded than other parts. Changing patterns of surface roughness were investigated with profiles, regression analysis and spectral analysis. Majority of plates showed decrease in small-scale roughness, but it depends on microstructures of the plates rather than general hardness or other factors. SEM inspection results supported this idea.