• Elastomers and Composites
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• 제46권2호
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• pp.94-101
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• 2011

종래의 방사선 차단막은 납판이나 납 분말을 과량 배합하여 사용되고 있기 때문에 무거울 뿐만 아니라 인체중독의 위험성이 있다. 또한 작은 핀홀이 존재할 경우 방사선의 직접 투과 위험성이 있는 단점이 있다. 본 특집에서는 최근 선진국을 중심으로 연구가 활발한 다층구조의 고분자 방사선 차단막 기술에 대해 특허분석과 문헌고찰을 중심으로 소개한다. 특히 판상형 나노무기입자를 이용한 방사선 차단 및 내구성 향상에 대한 새로운 개념을 소개한다.

• Imaging Science in Dentistry
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• 제30권4호
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• pp.259-263
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• 2000

Purpose: Upper cervical vertebrae are commonly imaged together with the jaw bones in panoramic radiography. There have been many studies investigating the possible role of mandible as an indicator of osteoporosis. But the result doesn't show unanimity. This study measured bone densities of mandible and second and third cervical vertebrae to find out any relationship between these two areas. These results may contribute in panorama being used as a screening method in detecting possible osteoporotic patient. Materials and Methods: Randomly selected 226 digitized panoramic images with cervical vertebrae shadows from 156 dental patients between 5 to 80 years of age were used. And the bone densities of second and third cervical vertebrae, apical areas of first and second mandibular molars and interdental areas were measured. The bone density measurements were restricted to the cancellous bone and the average and standard deviations and paired t-tests were done to each measurements. Results: All the measurements were statistically significantly related. The best relationship was found between the third cervical vertebrae and first and second mandibular apical areas. The average and standard deviations of the measured bone density ratios of these areas were 1.20±0.45 and 1.34±0.48 each. Conclusion: Patients whose panoramic bone density of the third cervical vertebrae are much below those of mandibular first or second molar apical areas may have osteoporosis.

• 한국통신학회논문지
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• 제32권7B호
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• pp.403-410
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• 2007

IPv6 유무선 로컬 네트워크에서 이웃하는 호스트와 라우터를 발견하기 위한 목적으로 ND (Neighbor Discovery) 프로토콜이 제안되었다. 그러나 ND 프로토콜은 악의 있는 사용자가 프로토콜 메시지를 위조하여 정상적인 호스트나 라우터로 위장하는 것이 가능하기 때문에 네트워크 공격에 취약한 문제를 가지고 있다. ND 프로토콜을 보호하기 위한 목적으로 SEND (Secure Neighbor Discovery) 프로토콜이 제안되었다. SEND 프로토콜은 주소 소유권 증명, 메시지 보호, 재현 공격 방지, 그리고 라우터 인증 메커니즘을 제공한다. 본 논문에서는 IPv6 네트워크상에서 핵심적으로 운용될 프로토콜중의 하나인 SEND 프로토콜을 설계 및 구현하다. 또한 본 논문에서 구현한 SEND 프로토콜을 IPv6 네트워크상에서 실험함으로써 SEND 프로토콜의 공격 방어 능력과 프로토콜의 성능을 평가하고 분석한다.

• 대한치과기공학회지
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• 제40권3호
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• pp.151-162
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• 2018

Purpose: The main purpose of this study is to develop assessment measures for the quality of service for dental labs. Methods: In order to construct the measure of service quality assessment for dental labs, relevant modifications were extracted around theoretical studies, and the survey was conducted on dental technician workers through internet survey. final scale questions were extracted through exploratory factor analysis and confirmed factor analysis of measurement variables, the demographic characteristics of the subjects and the perceptual difference of dental labs were analyzed for the extracted variables. Results: The final five variants of the interactive factor analysis that include the ability to change employee growth, reliability, responsiveness, materiality, interoperability, confirmatory factor analysis excludes variations in employee growth wages, welfare benefits, by changing its name to network capabilities, the quality of service factors for the final dental labs consisted of five variations: network competence, reliability, responsiveness, materiality and interoperability. Conclusion : The service quality of the dental labs showed that the reliability of the product related to the dental materials and the product production responsiveness related to the production order, the Materiality of the materials and equipment of the dental labs, the Interoperability responsiveness related to dental orders, And the importance of network capability to form a mutual network.

• International Journal of Human Ecology
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• 제13권1호
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• pp.29-37
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• 2012

This study examined risk and protective variables related with the continuity of developmental risks among 136 infants, aged 4-10 months. Using the Denver Developmental Screening Test, 136 infants among 2978 infants in the first wave of the Korea Child Panel were classified into the developmental risk group. Among the 136 risk group infants, 45 infants stayed in the risk group (continuing risk group) and the other 91 infants moved into the normal group (recovering risk group) after 1 year. Group differences were tested in the levels of infant, mother and father variables to examine which variables were associated with the continuity of developmental risks for a year. Variables indicating parents' marital relationships such as the mothers' marital satisfaction and conflict of the first wave and the fathers' marital satisfaction of the second wave significantly distinguished the continuing from the recovering risk group. In addition, there were significant group differences in the levels of mothers' self-efficacy in the first wave. The findings suggest that the exposure to marital conflict during infancy is associated with the continuity of developmental risks.

• 한국소음진동공학회논문집
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• 제14권5호
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• pp.370-376
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• 2004

The overall aim of this paper is to determine coupling loss factor of welding point between shell and cylinder using loss factor and structural loss factor. For this purpose, two kinds of loss factor were adopted. One is loss factor of each sub structure, another is structural loss factor based on the complex welded or assembled structure. Using these two parameters, it ispossible to derive the coupling loss factor which represent characteristic condition of SEA theory. Coupling loss factor of conjunction in complex structure was expressed as power balance equation. The derived equation for a coupling loss factor has been simplified on the assumption of one way (uni-directional) power flow between multi-sub structures. Using these conditions, it is possible to find the equation of coupling loss factor expressed as above two loss factors. To check the effectiveness of above equation, this paper used two-stage application. The first approach was application between simple cylinder and shell. The next was adopted rotary compressor. Rotary compressor has three main conjunctions between shell and internal vibration part. This equation was applied to find out the optimum welding point with respect to reduce the noise propagation. It shows the effective tool to evaluate the coupling loss factor in complex structure

• 대한한방내과학회지
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• 제40권6호
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• pp.1043-1050
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• 2019

Objectives: This study aimed to investigate the effects of Gyejigabuja-tang on liver function in patients with musculoskeletal disease. Methods: This research compared and analyzed data from liver function tests on patients who were treated with Gyejigabuja-tang during 17.98±1.78 days. Results: No significant effects appeared in the liver function of patients who were treated with Gyejigabuja-tang. Conclusions: This study suggests that Gyejigabuja-tang, which includes Aconiti Radix Lateralis Preparata, known as a toxic herb, may be used without causing significant liver injury if administered correctly as in this study.

• 한국어류학회지
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• 제4권2호
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• pp.55-62
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• 1992

1990년 3월부터 10월까지의 기간에 전남 승주군 주암면을 중심으로 주암댐 일대의 어류상(魚類相)을 조사하기 위하여 5개 조사지역에서 채집조사를 실시한 결과 11과(科) 23속(屬) 28종(種)의 어류(魚類)를 채집하였다. 댐 상류의 4개지역은 유속이 빠르고 댐 하류는 유속이 완만한 지역을 택하였다. 종(種)구성비에서 우세종은 Zacco platypus, Acheilognathus limbata, 그리고 Zacco temmincki였다. 한반도(韓半島) 고유종(固有種)으로는 Acheilognathus yamatsutae, Sarcocheilichthys variegatus wakiyae, Coreoleu-ciscus splendidus, Microthysogobio yaluenis. Cobitis longicorpus, Pseudobagrus koreanus, Liobagrus. mediadiposalis, Odontobutis platycephala등 8종이 채집되었다. 출현한 개체수는 잉어과(科)(Cyprinidae)어류가 86.71%로 가장 높았고, 바다빙어과(科)(Osmeridae)어류가 5.2%였다.

• Child Health Nursing Research
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• 제23권4호
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• pp.494-504
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• 2017

Purpose: The aim of this study was to analyze Neonatal Intensive Care Unit nurses' behaviors while soothing newborns with bronchopulmonary dysplasia. Methods: An observational study was used to assess nurses' soothing behaviors. Data were collected from September, 2012 to March, 2013 using an audio-video recording system. Participants were eight babies and 12 nurses caring for those babies. After obtaining parental permission, the overall process of each episode from nurses' engagement in soothing to the end of soothing was recorded. Then a researcher interviewed each participating nurse. Data from 18 episodes were transcribed as verbal and nonverbal nursing behaviors and then categorized by two researchers. Results: There were 177 observed soothing behaviors which were classified with the five sensory-based categories (tactile, oral, visual, auditory, vestibular). Most frequently observed soothing behavior was 'Gently talking' followed by 'Removing irritant', and 'Providing non-nutritive sucking'. Nurses' perceived soothing behaviors were similar to the observed soothing behaviors except for 'Gently talking'. Conclusion: Nurses used diverse and mixed soothing behaviors as well as recognizing those behaviors as essential nursing skills. Nurses' soothing behaviors identified in this study can be used to comfort babies and to enhance their developmental potential in accordance with individual characterstics or cues.

• 한국항행학회논문지
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• 제14권2호
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• pp.143-150
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• 2010

사물 또는 개념을 포함하는 개체들 간의 관계성을 일컫는 온톨로지는 다양한 시나리오의 정보서비스를 구현하는데 적용되고 있다. 그것은 하나의 개체에 대하여 그것을 둘러싸고 있는 다른 개체들이 어떤 것이 있고, 어떤 관계를 맺고 있는 지를 파악함으로써 보다 정확하게 이해할 수 있다는 데 있다. 역사적 사건들을 기술하는데 있어서 시공간적 위치는 그 사건에 대한 역사적 상황을 포괄적으로 표현한 것이라고 할 수 있다. 따라서 시공간적 위치정보는 역사적 사건들을 서로 연결하는 중요한 매개체가 된다. 우리는 이 논문을 통하여 역사적 사실 또는 사건들을 기반으로 하는 역사정보서비스에 있어서 정보에의 접근 및 검색 방법에 대한 사용 시나리오를 분석하고, 시공간의 틀 속에서 역사 이야기를 구성하기 위한 온톨로지 설계 방법을 제안한다.