• 한국포장학회지
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• 제22권3호
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• pp.163-168
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• 2016

본 연구에서는 국내 페트병의 경량화 가능성을 파악하기 위해 780종 이상의 빈용기 무게와 표시 용량의 상관관계를 분석하였다. 페트병은 사용목적에 따라 상압병(생수류), 내열병(쥬스류), 내압병(탄산류), 및 장기보관사용병(소스류)으로 구분하였으며 수집된 빈용기 무게와 표시 용량을 기반으로 각 페트병 종류별 경량화 지수(Lightness Index; L)를 산출하였다. 페트병 원천감량 설계 시 이용가능한 권고 기준 및 최적 기준을 경량화 지수를 이용하여 설정하였다. 예로 500 mL 생수병을 감량화 설계 기준에 맞게 생산할 경우 최적기준 반영시 약 4 g의 감량화가 가능하다. 작성된 설계 기준은 이미 관련 업계에 배포되었으며 생수병을 중심으로 적정 기준 정도의 경량화가 이루어지고 있다. 제시된 페트병 설계 기준은 국내외에서 출시된 페트병을 분석하여 무게 분포 특성을 반영한 결과이므로 현재 출시된 제품의 경량화 정도와 향후 개발되는 제품이 시장에서 어느 정도의 원천감량설계인지 알 수 있는 자료로 활용될 수 있을 것이다.

• 디지털융복합연구
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• 제15권12호
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• pp.381-391
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• 2017

본 연구의 목적은 낙관성을 매개로 스트레스가 행복지수에 주는 영향을 파악하고자 하는데 있다. 대상자는 G광역시 소재 3개 대학 간호학과 학생 중 임상실습경험이 있는 3, 4학년을 대상으로 시행하였으며, 362부의 설문지를 연구 자료로 사용하였다. 자료분석은 회귀분석과 SPSS Macro 및 부트스트래핑(bootstrapping) 방법을 이용하여 대학생의 스트레스와 행복감에 있어 낙관성의 매개효과를 검증하였다. 연구결과 스트레스, 행복지수, 낙관성은 유의한 상관관계가 있었고, 스트레스가 대학생의 행복지수에 직접적인 영향을 주었다. 즉, 스트레스의 수준이 높을수록 대학생의 행복지수를 저하시켰다. 낙관성은 스트레스와 대학생의 행복지수 사이에서 부분적으로 매개효과를 보였다. 따라서 대학생의 행복지수를 높이기 위해서는 스트레스 관리와 낙관성을 높일 수 있는 프로그램 전략의 하나로 행복증진 프로그램 개발 및 시행이 요구된다.

• Journal of Periodontal and Implant Science
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• 제28권3호
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• pp.465-475
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• 1998

The purpose of this study was to investigate the comparative effects of subgingival irrigation using some oral mouth rinses on early healing process of periodontal inflammation. The study population consisted of 13 patients with periodontal inflammation and distributed into 4 groups. Oral hygiene instruction, delicate scaling and root planing were done and then irrigated per 3 days during 2 weeks in situ with 1 of 4 solutions ; normal saline, C31G, Benzotonium chloride and tetracycline. Examination regarding probing pocket depth, plaque index, sulcular bleeding index, gingival index, gingival recession and leukocytes differential count was performed. Evaluation was made at the baseline and 2 weeks after non-surgical periodontal therapy. The results were as follows : 1. Clinical indices including probing pocket depth, plaque index, sulcular bleeding index, gingival index and gingival recession were significantly improved from baseline to 2 weeks. But there was no significant differences among 4 groups. 2. PMNs percent on leukocytes differential count was significantly decreased from baseline to 2 weeks on all groups. Those of tetracycline and C31G were significantly decreased than those of normal saline group. These results suggest that clinical indices were not different, but the decrease of inflammation were significantly different among some mouth rinses.

• 한국산림과학회지
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• 제100권2호
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• pp.184-201
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• 2011

본 연구는 2010년 3월부터 10월까지 춘천시를 도심하천, 하천상류 및 임연부, 도시림지역으로 나누어 귀화 식물 분포현황과 침입특성을 파악하였다. 조사한 결과 춘천시 내의 태백천유역과 도시림의 식물상은 81과 234속 295종 2아종 66변종 18품종 총 381종류가 분포하는 것으로 확인되었으며, 이 중 귀화식물은 가시박, 유럽나도냉이, 말냉이, 족제비싸리, 붉은토끼풀, 돼지풀, 단풍잎돼지풀, 미국쑥부쟁이, 애기수영 등 총 41종류가 나타났다. 춘천시 내의 태백천유역과 도시림의 귀화율(NI)과 도시화지수(UI)는 각각 10.79%, 15.30%로 확인되었으며, 귀화식물침입지수(II)는 도심하천지역이 63.41%, 하천상류 및 임연부지역이 97.56%, 도시림지역이 19.51%로 확인되었다.

• 공업화학
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• 제34권4호
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• pp.388-396
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• 2023

연소성 물질의 화재위험성 평가를 하기 위하여 Chung's equations-X, Chung's equations-XI, 그리고 Chung's equation-XII 를 새로 정립하였다. 화재위험성지수-XII (fire risk index-XII, FRI-XII)와 화재위험성등급(fire risk rating, FRR)을 산정하였다. 시험편은 녹나무, 벚나무, 고무나무, 느릅나무를 선택하였다. 콘칼로리미터(ISO 5660-1)를 사용하여 시험편에 대한 연소 특성을 시험하였다. Chung's equations에 의해 산정된 화재성능지수-X (fire performance index-X, FPI-X)과 화재성장지수-X (fire growth index-X, FGI-X)은 각각 89.34~1696.75 s²/kW와 0.0006~0.0107 kW/s² 로 나타났다. 또한 화재성능지수-XI (fire performance index-XI, FPI-XI)과 화재성장지수-XI (fire growth index-XI, FGI-XI)은 각각 0.08~1.48과 0.67~11.89으로 나타났다. 화재위험성 등급인 화재위험성지수-XII (FRI-XII)는 녹나무가 148.63 (화재위험성등급: G)으로 화재위험성이 매우 높은 목재로 나타났다. 그러므로 휘발성 유기 화합물을 다량 함유하고 있는 연소성 물질은 FPI-X과 FPI-XI이 낮아지고, FGI-X과 FGI-XI이 높아짐에 의하여 FRI-XII가 높은 값을 나타내었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제21권3호
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• pp.288-297
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• 1999

This study has been carried out in order to measure the thickness of soft-tissue on lateral cephalographs based on body mass index(BMI) and the change in soft-tissue thickness after surgical correction of mandibular protrusion. The control material in cephalometric study comprised students at The Dental College, 38 persons, aged 21~24 years and the patient material comprised 20 women and 12men, aged 19~28 years with mandibular protrusion.The thickness of the soft-tissue based on BMI in control and study groups, the comparison between them, immediate postoperative change in the thickness, 6 months after surgery, ratio of soft-tissue response and correlation was established through various statistical methods. The result were as follows : 1. The groups based on BMI showed significant differences each other as regards the linear measurements. The thickest soft-tissue was measured 13.6mm, 15.47mm, 16.76mm at Ss, the thinnest at G' 6.0mm, 6.7mm, 7.26mm respectively. 2. The differences between control and experimental groups based on BMI showed to be significant. There were no differences at G'. The soft-tissue in prognathic patients was thicker at Ss, Ls and thinner at Li, Ls, Pg', Gn', Me'. Differential gap was greater in overweight groups. 3. The immediate soft-tissue change after surgery showed the increase at Li, Ls, Pg', Gn', Me' except G', Ls in all groups. 4. The postoperative soft-tissue change 6 months after surgery was similar with immediate change. The soft-tissue shows the increase in the thickness at Li, Pg', Gn', Me' and the greatest difference occurred at Li, 1.1mm, 0.98mm, 1.2mm respectively. 5. The patients with lower BMI index showed higher soft-tissue response to bony movement at Pg'. The immediate response ratio was 91%, 87%, 81% in A,B,C groups respectively, the response 6 months after surgery showed 96%, 91%, 84%.

• 한국수산과학회지
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• 제48권5호
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• pp.768-775
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• 2015

Seasonal variability in the marine seaweed community structure was examined in the intertidal zones at nine study sites in Hallyeohaesang National Park, on the southern coast of Korea from March to October 2014. A total of 145 seaweeds were indentified, comprising 15 green, 41 brown and 89 red algae. Coarsely branched seaweeds were the dominant functional group, comprising 58.95% in species number, whereas filamentous, sheet, thick leathery, crustose and jointed calcareous forms comprised 2.63-17.72% each. The seaweed biomass averaged 358.00 g dry wt/m² and it was maximal at Somaemuldo (847.64 g dry wt/m²) and minimal at Gamam (56.51 g dry wt/m²). Based on biomass, the dominant and subdominant seaweeds were Ulva australis at Gamam, Sargassum thunbergii at Sangju, Ulva australis and S.fulvellum at Neukdo, S.horneri at Dala-Bijindo-Somaemuldo, S. thunbergii at Dapo, and Corallina pilulifera at Songdo. Community indices were as follows: dominance index (DI), 0.43-0.71; richness index (R), 8.26-16.50; evenness index (J'), 0.36-0.54; and diversity index (H'), 1.57-2.19. In conclusion, we found that both biomass and the community structure of seaweeds in Hallyeohaesang National Park were similar to those in other studies of the Southern Sea along the Korean peninsula, and that Hallyeohaesang National Park is a relatively favorable habitat for seaweeds. Future studies should examine the changes in seaweed composition and biomass as they relate to climate change and environmental pollution.

• 한국수산과학회지
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• 제50권1호
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• pp.55-64
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• 2017

Seasonal variability in algal community structure was examined at the intertidal zones of five study sites on the Taean Peninsula, on the western coast of Korea, from February 2014 to November 2015. A total of 118 species of marine algae, comprising 17 green, 24 brown and 77 red algae, were identified. The maximum number of species was observed at the Mohang site (75 species), and the minimum at the Yeonpo site (46 species). The seaweed biomass was $160.24g\;dry\;wt./m^2$ on average, and was maximal at Uihang ($519.04g\;dry\;wt./m^2$) and minimal at Yeonpo ($19.03g\;dry\;wt./m^2$). Based on biomass, the dominant seaweeds at Taean peninsula were Sargassum thunbergii and Corallina pilulifera. Community indices were as follows: richness index (R), 3.21-5.01; evenness index (J'), 0.33-0.38; and diversity index (H'), 0.90-1.12. Based on evaluation of the environmental states by the community indices, the ecological evaluation index (EEI) of Taean peninsula was "moderate". The overall species and biomass of seaweeds decreased after the oil spill. However, Hakampo previously showed a similar algal community structure. In conclusion, the algal community was temporarily affected by the oil spill, but rapidly recovered.

• Journal of Ecology and Environment
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• 제46권3호
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• pp.204-217
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• 2022

Background: Increasing land demands for food production have led to biodiversity loss and land degradation in the Madhupur Sal forest. Reforestation activities such as agroforestry and woodlot plantation support the conservation of diversity, restoration of forest and prevention of soil erosion in degraded natural Sal forest. Knowing about these reforestation activities, this study is needed to compare the species composition, richness, and soil nutrients of these two plantation activities to the natural Sal forest in the degraded Madhupur Sal forest in Bangladesh. Results: The analysis showed that in between the reforestation activities, the highest Shannon-Wiener index (1.79), evenness (0.60) and Simpson's index (0.79) were found in the agroforestry site compared to the woodlot plantation site. On the contrary, the highest species richness (n = 14), tree basal area (19.56 m² ha^-1), Margalef's index (1.96) were recorded in woodlot plantation than in the agroforestry site. We observed that at 0-15 cm depth, soil organic matter (2.39%), total nitrogen (0.14%), available phosphorous (62.67 ㎍ g^-1) and exchangeable potassium (0.36 meq/100 g) in agroforestry plots were significantly higher compared to other forest sites. At topsoil (15-30 cm depth), soil organic matter (1.67%) and available phosphorous (21.09 ㎍ g^-1) were found to be higher in agroforestry site. Conclusions: Both reforestation approaches improved soil function, although woodlot plantation had the higher species richness. Therefore, plantation activities by the sustainable implementation of these two practices are the best alternative to restore the biodiversity, richness and conserve soil fertility in the Madhupur Sal forest of Bangladesh.

• 생태와환경
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• 제44권2호
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• pp.144-154
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• 2011

섬강의 어류 군집구조 및 멸종위기어종 꾸구리(Gobiobotia macrocephala)와 돌상어(G. brevibarba)의 서식현황을 알아보기 위하여 2010년에 10개 지점을 선정하여 계절별로 조사하였다. 총 출현한 어종은 10과 37종이었고, 우점종은 피라미(Zacco platypus, 36.2%), 아우점종은(13.2%)와 돌상어(12.2%), 그 다음으로 쉬리(Coreoleuciscus splendidus, 8.1%)와 밀어(Rhinogobius brunneus, 4.9%) 등의 순으로 우세하게 출현하였다. 출현종 중 한국고유종은 18종(48.6%)이였으며, 환경부 멸종위기종은 꾸구리와 돌상어 2종이 출현하였다. 지점별 출현한 어종을 근거로 유사도 분석을 한 결과 상류(St. 1~3)와 중류(St. 4~6), 하류(St. 7~10)로 잘 구분되었으며 하류로 갈수록 우점도 지수는 대체로 낮아지고, 다양도 지수와 종 풍부도 지수는 대체로 높아지는 경향을 보였다. 멸종위기 어종인 꾸구리는 섬강 하류의 자갈과 돌이 쌓인 여울에서 서식하였고, 돌상어는 전구간에 쌓인 여울지역에 비교적 높은 비율로 서식하고 있었다.