• 한국가스학회지
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• 제11권3호
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• pp.44-48
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• 2007

본 연구는 코일직경변화에 따른 헬리컬 코일 가스냉각기내 초임계 $CO_2$의 냉각 열전달 특성에 대해 실험적으로 조사하였다. 냉매 순환루프의 주요구성품은 수액기, 변속펌프, 질량유량계, 예열기, 헬리컬 코일형 가스냉각기(시험부)로 구성된다. 시험부는 내경 4.55 mm의 평활 동관과 26.75 mm와 41.35 mm인 코일직경으로 이루어져 있다. 냉매질량유속은 $200kg/m^2s$에서 $800kg/m^2s$가지 변화시켰고, 가스냉각기의 입구압력 범위는 7.5 MPa에서 10.0 MPa까지이다. 코일직경이 26.75 mm인 가스냉각기내 이산화탄소의 냉각열전달 계수가 코일직경이 41.35 mm인 열전달 계수보다 높은 것으로 나타났다. 또한 초임계 상태에서 제안한 종래의 냉각 열전달 상관식과 비교한 결과, 대부분의 상관식이 과소예측되었고, 그 중에서도 이산화탄소의 냉각 열전달 계수는 Pilta 등이 제안한 상관식과 좋은 일치를 보였다. 하지만, 유사임계 온도 영역부근에서는 실험데이터가 더 큰 것으로 나타났다.

• 펄프종이기술
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• 제29권3호
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• pp.7-16
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• 1997

The constituents of deposits on paper machine and holes/spots in paper have been studied by consequently a combination of analytical techniques, such as FTIR, Py-GC-MS, and. EDS. FTIR spectroscopy was used prior to Py-GC-MS and EDS analysis, as preliminary analysis technique. The analysis of organic components were carried out with the use of a pyrolysis unit connected to a GC-MS, and inorganic components in ash were analysed by SEM equipped with an EDS analyzer after pyrolysis at 59$0^{\circ}C$. The deposits on the dryer section were complex pitch, which was the mixture of the organic contents of fatty acid ester and starch, and the inorganic contents of talc, clay, and calcium carbonate. The complex pitch was estimated to come from the coated broke. We knew the deposits on the metering rod of sym-sizer were associated with the interaction of unstable AKD and CaCO$_3$. The compositions of holes or spots varied considerably and were associated with chemical interaction within the system. The holes, spots, and blotches in the finished paper were PE and PP that were streamed out from pulp sources, complex pitch that were caused by the interaction of the different additives in the system, polymer such as flexible PVC that used for the prop of palette, and hot melt as adhesives that came from the inadequate handling of broke. In addition, we identified that poly(caprolactam) which is used for forming fabrics or press felts, could be mixed with the raw materials by accident and results in streak on coating.

• 보건행정학회지
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• 제3권1호
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• pp.25-52
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• 1993

Variation in the utilization of medical services is a very important issue in cost containment and quality assurance of health care. Practice variation directly affects health care expenditure especially in fee-for-service system, which is the payment system of health insurance in Korea. In addition to cost issue it is generally accepted that variations in medical practice and the cost of inpatient care suggest the possibility of inappropriate quality of care. This study is to closely examine the patterne and degrees of variation in cost structure of inpatient care among types of hospital and individual hospitals in some tracer diseases, and also to inquire into the service items which contribute much to the variation of total medical care cost. Foru common diseases, i.e. Cesarean Section, appendectomy, cataract extraction and pediatric pneumonia, were selected as tracer diseases. In most tracer diseases there were statistically significant differences in total medical care cost among hospitals in same type of hospital as well as among types of hospital(p<0.01). When total medical care cost were subdivided into the types of service, cost of medication and diagnostic examination varied the most prominenly. When the cost of medication were subdivided again, cost of parenteral antibiotics showed the most prominent variation. Of total medical care cost, medication was most contributory to the variation of total medical care cost(58.1~82.3%), and cost of antibiotics was most contributory to the variation of medication cost(63.9~92.2%). The results of study implicated that reducing the variation of medication may plays a significant role in containing the cost of inpatient care. In order to sort out the factors affecting practice variations including drug prescription pattes further researches are required.

• 보존과학회지
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• 제35권1호
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• pp.41-49
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• 2019

This study analyzes the material characteristics of stone tools of the Paleolithic period excavated from the Osong site, located at the project site for the creation of the Osong 2nd Life Science Complex, and estimates the provenance of the stone materials. Because the stones had been buried for a long time, their surfaces had become heavily weathered yellow or yellowish-brown, and the magnetic susceptibility values varied from 0 to 15(${\times}10^{-3}SI$). The excavated stone tools were rocks with various magnetic susceptibility values that could not be specified. Five stone tools subjected to destructive analysis were divided into two groups, one with a value of 1-3(${\times}10^{-3}SI$) and the other with a value of 5-9(${\times}10^{-3}SI$), both based on visible characteristics. The results of the thin-section analysis showed that most of the stone tools were basaltic rocks comprising plagioclase, quartz, and pyroxene, and some had iron content as high as 20 wt.%. These findings and the present geological map suggest that the stone tools were not made from the surrounding rocks because there are no areas containing basaltic rocks surrounding Bongsan-ri in Osong-eup. Andesite and tuff are distributed along with basaltic rocks in the Doan-myeon area in Jeongpyeong-gun, Chungcheongbuk-do Province, but the distance from the excavation site is too far. To determine whether this region is actually related to the provenance of the raw rock, it is necessary to conduct additional field surveys and comprehensive and precise analyses.

• 한국융합학회논문지
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• 제10권7호
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• pp.55-62
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• 2019

본 연구는 구강건강을 위해 사용하고 있는 칫솔을 특허검색이 가능한 KIPRIS에서 2008년부터 2017년까지 10년간 등록된 칫솔에 대한 467개의 특허정보를 분석하였다. 칫솔구성을 기준으로 8개로 대분류 하였고, 세부정보를 소분류 하였다. 연간 특허수량을 분석하기 위해 출원연도를 분석하여 정리하였다. 그 결과 특허가 가장 많은 것은 칫솔모에 대한 특허였으며 뒤이어 칫솔 외 기능추가 특허, 전동칫솔 특허, 칫솔헤드에 대한 다른 형태로의 칫솔 특허, 칫솔목에 대한 특허, 칫솔질 습관 교정에 대한 특허, 칫솔 핸들에 대한 특허 순이었다. 다양한 소분류의 특허는 칫솔 외 기능 추가 특허였으며 2012년 칫솔모에 대한 특허건이 25개로 제일 많았으며, 2017년 소폭 감소하는 칫솔특허 대비 유일하게 증가하고 있는 특허는 칫솔질 습관 교정에 대한 특허와 칫솔 핸들에 대한 특허였다. 2009년부터는 칫솔에 대한 특허수가 꾸준히 증가하고 다양해진 모습을 확인 할 수 있다.

• Nuclear Engineering and Technology
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• 제53권6호
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• pp.2000-2010
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• 2021

Mechanical moduli, such as Young's modulus (E), Bulks modulus (B), Shear modulus (S), longitudinal modulus (L), Poisson's ratio (σ) and micro Hardness (H) were theoretically calculated for (100-x)TeO₂+x MgO glasses, where x = 10, 20, 30, 40 and 45 mol%, based on the Makishima-Mackenzie model. The estimated results showed that the mechanical moduli and the microhardness of the glasses were improved with the increase of the MgO contents in the TM glasses, while Poisson's ratio decreased with the increase in MgO content. Moreover, the radiation shielding capacity was evaluated for the studied TM glasses. Thus, the linear attenuation coefficient (LAC), mass attenuation coefficient (MAC), transmission factor (TF) and half-value thickness (𝚫_0.5) were simulated for gamma photon energies between 0.344 and 1.406 MeV. The simulated results showed that glass TM10 with 10 mol % MgO possess the highest LAC and varied in the range between 0.259 and 0.711 cm^-1, while TM45 glass with 45 mol % MgO possess the lowest LAC and vary in the range between 0.223 and 0.587 cm^-1 at gamma photon energies between 0.344 and 1.406 MeV. Furthermore, the BXCOM program was applied to calculate the effective atomic number (Z_eff), equivalent atomic number (Z_eq) and buildup factors (EBF and EABF) of the glasses. The effective removal cross-section for the fast neutrons (ERCSFN, ∑_R) was also calculated theoretically. The received data depicts that the lowest ∑_R was achieved for TM10 glasses, where ∑_R = 0.0193 cm² g^-1, while TM45 possesses the highest ERCSFN where ∑_R = 0.0215 cm² g^-1.

• 한국작물학회지
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• 제35권1호
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• pp.58-64
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• 1990

최근 국내에서 연구가 시작되고 있는 신규 식물생장조정제인 brassinolide류와 기존의 auxin류를 혼용하였을 경우 상호작용성을 구명하여 농업적 이용의 기초자료를 얻고자 몇가지 생물검정법을 이용하여 상호작용의 결과를 분석해 본 결과를 요약하면 다음과 간다. 1. 벼 엽신기부굴절검정에서는 두 화합물의 저농도 혼용조합에서 길항적인 반응을 보였으나, 대부분의 조합에서는 상가 또는 상승작용을 하였으며, 고농도의 혼용일수록 상승효과가 높았고, IAA가 2, 4-D에 비해 다소 혼용효과가 높았다. 2. 귀리 자엽소신장검정에서는 HBR의 농도에 관계없이 IAA 0.1ppm 이하에서는 상승작용을 하였으나 0.3ppm 이상의 혼용에서는 상가적인 반응을 나타내었다. 3. 무 하배축신장검정에서는 자엽의 유무에 의해 반응이 다르게 나타났는데, 자엽을 제거한 절편에서는 IAA 3ppm과 HBR과의 혼용조합을 제외하고는 대부분의 혼용조합이 길항적인 반응을 보였다. 4. 이상에서와 같이 검정방법간 혼용효과가 뚜렷한 차이가 있었으며, 공시재료에 따라 상호작용의 효과가 다르게 나타났는데 auxin의 함량이 비교적 높은 생장점을 가진 절편에서는 대체로 길항작용을 보인 반면, 선단부를 제거하여 내생호르몬이 불안정한 절편에서는 상가 또는 상승작용을 보였다.

• 한국산업융합학회 논문집
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• 제26권4_2호
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• pp.697-703
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• 2023

Intertidal zones, akin to tidal flats, are among the potential areas where underwater cultural heritage might be submerged. However, the shallow depths in these regions present challenges for conventional vessel-based survey methods. Moreover, during low tides, intertidal zones transform into tidal flats, limiting the efficiency of survey efforts due to restricted access and potential risks. As a result, proper underwater cultural heritage surveys encounter difficulties in these environments. In recent times, extensive research is underway to address these issues by investigating underwater cultural heritage surveys in intertidal zones, encompassing diverse fields, including equipment-based investigations. This study aimed to explore the feasibility of utilizing unmanned aerial vehicles (UAVs) to conduct intertidal cultural heritage surveys, employing aerial photography and 3D mapping to create detailed orthoimages and 3D models. The study focused on assessing the potential application of these techniques for cultural heritage surveying within intertidal zones. Notably, the survey conducted in Jindo's Naesan-ri demonstrated high-resolution capabilities, enabling the distinction of actual pottery fragments mixed within gravel fields. Similarly, in the survey of Jindo's Byeokpa-hang, it was found that a wooden pillar structure existed in a section about 200m long. The integration of various sensors, including LiDAR, with UAVs allows for diverse investigation possibilities, including bathymetric measurements, and is expected to facilitate the acquisition of varied datasets for further research and assessment.

• 대한치과의료관리학회지
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• 제6권1호
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• pp.43-47
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• 2018

Online data can be explored for topics browsed by an unspecified population to detect professional information demands more quickly. The purpose of this study was to collect and analyze online questionnaires in order to find information required by dental hygienists. We analyzed the frequency of posting words after isolating nouns from questions of the Korean Dental Hygienists Association homepage's Q & A section, the Naver Knowledge-iN service, and a dental hygienists' online meeting site in Naver. We found that queries of the Korean Dental Hygienists Association's homepage were concentrated on education renewal and license notification. The queries about dental hygienists in the Naver Knowledge-iN service used words related to job or career choice, and the queries of the dental hygienist-affiliated site had many words related to dental practice, dental work, and turnover. This study showed that the information needs of unspecified dental hygienists varied depending on the online environment such as homepage, blog, and information service.

• 한국지역지리학회지
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• 제19권2호
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• pp.234-245
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• 2013

지리산국립공원 종주등산로의 침식속도를 파악하기 위하여 노고단~삼도봉 구간에서 등산로의 형태별 유형을 고려하여 16개 측량지점을 선정하고 2010년 11월부터 2012년 4월까지 18개월간 등산로의 횡단면을 측량하였다. 모든 지점에서 실질적인 침식이 발생하여 등산로 횡단면이 확대되었으나 토양침식량은 지점에 따라 차이가 커 $54.9{\sim}908.8cm^2$, 일평균 침식속도로는 $0.1{\sim}1.72cm^2$의 범위를 보인다. 유형별로는 평탄면형 $172.4cm^2$, 얕은 우곡형 $109.3cm^2$, 깊은 우곡형 $493.9cm^2$, 외벽형은 $573.2cm^2$, 양벽형 $556.8cm^2$이다. 그러나 유형에 관계없이 등산로의 횡단면 변화는 노면보다는 측벽에서 크게 나타났다. 시기별로는 5월~10월의 침식량이 11월~4월보다 많았으며, 2011년 11월~2012년 4월에는 퇴적량이 침식량보다 많아 등산로 횡단면이 줄어들었다. 조사구간에서는 3월과 4월에 등산로 측벽에 서릿발작용으로 토양입자가 쌓이고 5월 이후 강수량이 많아지면서 우세로 제거되며 등산로 침식을 주도한다. 서릿발 발달에 유리하므로 북향 측벽의 침식량이 남향보다 크다. 4월에 관측되는 동결기의 작은 침식량과 등산로 횡단면의 축소는 동상과 서릿발작용에 작은 강우량과 일시적인 답압 중단이 가세하여 만들어낸 계절적인 현상이다. 산악국립공원의 등산로 관리 측면에서 등산로의 침식량과 요인에 대한 지속적인 관측이 이루어지는 등산로 침식 모니터링체제를 구축하는 것이 필요하다.