• 대한지리학회지
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• 제47권3호
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• pp.315-327
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• 2012

한반도 남서부에 위치한 영암 일대의 화강암 구릉대에는 적색의 지표피복물들이 일반화되어 나타나고 있으며, 이를 고온다습한 고기후의 산물로써 성대토 개념으로 간주되어 왔다. CIA와 A-CN-K, A-CNK-FM 도식을 이용하여 이들 적색의 풍화층이 지니는 화학적 풍화 특색을 살펴본 결과, 모암에서 사장석이 완전 풍화에 준하는 수준의 강한 화학적 풍화가 일어남으로써 사질의 풍화층이 형성되었고, 풍화층이 형성된 이후로는 칼륨 장석의 용탈에 의해 풍화층의 화학적 변화가 일어나고 있는 상태이다. 그러나 일라이트와 같은 일차 광물의 수준을 넘어서지 못한 상태에 있으며, 라테라이트 단면에서 나타나는 카올리나이트와 같은 2차 광물로의 화학적 풍화는 진전되지 못한 상태이다. 화학적 풍화의 결과로서 알칼리 성분들은 용탈에 의해 함량이 낮아진 상태이지만, 철분과 마그네슘 같은 유색 광물들은 상대적으로 미약한 용탈이 발생하여 풍화층의 적색화가 이루어지고 있는 것으로 판단된다.

• 실천공학교육논문지
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• 제11권2호
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• pp.251-258
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• 2019

카메룬 유일의 직업훈련교사 자격 훈련기관인 '카메룬 국립직업훈련교육원(NIVTPD)'의 설립을 위해 본 연구진은 NIVTPD의 마스터 교사들을 대상으로 교과과정 개발법, 교재 개발 방법 및 개발, 강의전략 수립법 및 강의지도서 작성, 강의계획 및 계획서 작성, 강의안 작성법 등의 역량 강화 훈련을 하였다. 또한 시범연수를 통해 실 강의까지 해봄으로써 실제 NIVTPD의 운영에 대비하였다. 이 논문은 NIVTPD에서의 훈련을 통해 얻은 내용이 강의실 수업 성과에 미치는 영향을 평가하기 위해 두 가지 다른 설문 조사(기초선 및 종료 선 조사)와 두 가지 다른 시험(진입 레벨 테스트(Pretest) 및 성취 수준 시험(Posttest))를 실시한 결과와 그에 따른 분석 결과를 포함한다. 설문 조사 결과는 직업훈련 인터페이스의 현재 상황을 파악하고 커리큘럼을 통합, 수정 및 개선하여 NIVTPD의 교육 프로그램을 개선하는 데 활용될 수 있을 것이다. 또한 시험 결과는 직업훈련교사의 교육학적 지식 수준을 파악하고 향후 자격을 수여하기 위한 지표로 사용될 수 있을 것이다.

• 한국지형학회지
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• 제19권4호
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• pp.123-137
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• 2012

한반도 남부에는 적색의 지표피복물이 나타나고 있으며, 학교 교육에서는 라테라이트성 적색토로 규정해 왔다. 줄포, 나주, 영암에 분포하는 화강암 구릉대의 적색화된 풍화층을 대상으로 CIA(화학적풍화지수)와 A-CNK 삼각도를 이용하여 분석해 본 결과, 칼슘과 나트륨의 용탈은 매우 강하게 진전되어 있지만 칼륨의 용탈이 미약한 상태이다. 스페인의 카올리나이트층과 카메룬의 라테라이트토와 비교해 보았을 때, 한반도 남서부 지역의 풍화물은 백운모와 일라이트 수준을 넘어서지 못하고 있는 상태이다. 단면 하부에서 상부로 갈수록 상대적 함량이 증가하는 철분은 지표피복물 적색화의 주요 요인이지만, 라테라이트토가 강한 화학적 풍화로 인한 잔적물인 철분에 의한 적색화라면, 연구지역의 적색화는 철분의 함량과 화학적 풍화 강도 모두 그에 못 미친다. 따라서 한반도 남부 지역에 나타나는 적색의 지표피복물들을 성대적 개념의 라테라이트성 적색토로 규정하기에는 현재의 연구가 많이 부족하며, 추후의 연구가 더 필요하다.

• Forest Science and Technology
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• 제14권4호
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• pp.181-191
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• 2018

This study was carried out in the teaching and research forest of the University of Dschang in Belabo, with the aim of analysing land-cover and land-use changes as well as carbon stocks dynamic. The databases used are composed of three Landsat satellite images (5TM of 1984, 7ETM + of 2000 and 8OLI of 2016), enhanced by field missions. Satellite images were processed using ENVI and ArcGIS software. Interview, focus group discussion methods and participatory mapping were used to identify the activities carried out by the local population. An inventory design consisting of four transects was used to measure dendrometric parameters and to identify land-use types. An estimation of carbon stocks in aboveground and underground woody biomass was made using allometric models based on non-destructive method. Dynamic of land-cover showed that the average annual rate of deforestation is 0.48%. The main activities at the base of this change are agriculture, house built-up and logging. Seven types of land-use were identified; adult secondary forests (64.10%), young secondary forests (7.54%), wetlands (7.39%), fallows (3.63%), savannahs (9.59%), cocoa farms (4.28%) and mixed crop farms (3.47%). Adult secondary forests had the highest amount of carbon ($250.75\;t\;C\;ha^{-1}$). This value has decreased by more than 60% for mixed crop farms ($94.67\;t\;C\;ha^{-1}$), showing the impact of agricultural activities on both forest cover and carbon stocks. Agroforestry systems that allow conservation and introduction of woody species should be encouraged as part of a participatory management strategy of this forest.

• Asian-Australasian Journal of Animal Sciences
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• 제8권4호
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• pp.353-356
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• 1995

The red cell X-protein, NADH-diaphorase 1, malic enzyme and serum arylesterase phenotypes of 50 Thai Longtail and 53 Cameroon X Thai Longtail ($F_1$) crossbred sheep were determined by horizontal starch gel electrophoresis. None of the economic traits was influenced by DIA1, ME and EsA phenotypes. However, XP phenotypes showed a highly significant association with body weight, body height, heart girth and back girth, with mean values of XP+ve phenotype greater than XP-ve. The $XP^+$ allele was associated with greater body weight, body height, heart girth and back girth.

• 과학교육연구지
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• 제41권1호
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• pp.135-151
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• 2017

This study set out to investigate the challenges to science teacher's teaching practices in the Anglophone sub-system of education in Cameroon secondary schools. A sample of 331 of these teachers was selected using the purposive sampling method. Data was collected by use of a questionnaire and was subjected to inferential analysis. The major findings from the multiple regression were challenges associated with the size and management of a science class have an effect on the teaching practices of a science teacher. However, challenges with availability of instructional resources did not have an effect on science teaching practices. Recommendations to solve the identified drawbacks include the provision of more classrooms to accommodate the ever growing population of students and the organization of many seminars through which teachers could be educated on how to handle classroom problems and improvise when necessary.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.371.1-371.1
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• 2002

Triterpenoids. Ursolic acid (1). 23-hydroxyursolic acid (2). and tormentic acid (3) were obtained by the hydrolysis of BuOH fraction of Cussonia bancoensis extract and further chromatographic isolation to test antinociceptive and anti-inflammatory effect of C. bancoensis (Aratiaceae). Compound 1 and 2 exhibited anti-nociceptive effects, which were determined by acetic acid-induced writhing test and hot plate test. However. the effect of tormentic acid was not significant (omitted)

• Journal of Forest and Environmental Science
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• 제38권3호
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• pp.184-194
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• 2022

Triplochiton scleroxylon K. Schum is the plant species most affected by logging activities in the East Region of Cameroon due to its market value. This logging has impacted the ecological niche of the fern plant for which limited research has been done. The aim of this study is to contribute towards improving knowledge of fern richness and biomass on T. scleroxylon within the Central African sub-region. Fern data collection was done on 20 felled/harvested T. scleroxylon where, in addition to fern inventory, fern biomass was collected by the destructive method. The diameter and height of T. scleroxylon measured were used as explanatory variables in allometric equations for fern biomass estimation. Fern inventory was characterized using diversity index. Eight fern species were recorded on T. scleroxylon (≈5 species/T. scleroxylon). The minimum diameter where fern could be found is 59.4 cm. The average fern biomass found was 23.62 kg/T. scleroxylon. Pearson correlation coefficient showed a positive correlation (r>0.55) between fern biomass and T. scleroxylon diameter. For allometric equation, the logarithmic model improved better the adjustment than the non-logarithmic model. However, the quality of the adjustment is improved more when only the diameter is considered as an explanatory variable. Fern biomass is estimated to 90.08 kg/ha^-1 with 76.02 kg/ha^-1 being lost due to T. scleroxylon exploitation in the study area. This study is a contribution towards increasing knowledge of fern diversity specific to T. scleroxylon, and also fern biomass contribution to climate change mitigation and the potential carbon loss due to T. scleroxylon exploitation.

• Journal of Radiation Protection and Research
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• 제47권4호
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• pp.237-245
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• 2022

Background: The current study reports measurements of activity concentrations of radon (²²⁰Rn) and thoron (²²⁰Rn) in dwellings, followed by inhalation dose assessment of the public, and then by the development of regulation and the national radon action plan (NRAP) in Cameroon. Materials and Methods: Radon, thoron, and thoron progeny measurements were carried out from 2014 to 2017 using radon-thoron discriminative detectors (commercially RADUET) in 450 dwellings and thoron progeny monitors in 350 dwellings. From 2019 to 2020, radon track detectors (commercially RADTRAK) were deployed in 1,400 dwellings. It was found that activity concentrations of radon range in 1,850 houses from 10 to 2,620 Bq/㎥ with a geometric mean of 76 Bq/㎥. Results and Discussion: Activity concentrations of thoron range from 20 to 700 Bq/㎥ with a geometric mean of 107 Bq/㎥. Thoron equilibrium factor ranges from 0.01 to 0.6, with an arithmetic mean of 0.09 that is higher than the default value of 0.02 given by UNSCEAR. On average, 49%, 9%, and 2% of all surveyed houses have radon concentrations above 100, 200, and 300 Bq/㎥, respectively. The average contribution of thoron to the inhalation dose due to radon and thoron exposure is about 40%. Thus, thoron cannot be neglected in dose assessment to avoid biased results in radio-epidemiological studies. Only radon was considered in the drafted regulation and in the NRAP adopted in October 2020. Reference levels of 300 Bq/㎥ and 1,000 Bq/㎥ were recommended for dwellings and workplaces. Conclusion: Priority actions for the coming years include the following: radon risk mapping, promotion of a protection policy against radon in buildings, integration of the radon prevention and mitigation into the training of construction specialists, mitigation of dwellings and workplaces with high radon levels, increased public awareness of the health risks associated with radon, and development of programs on the scientific and technical aspects.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.10033-10038
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• 2014

The aim of this study was to determine the prevalence of tobacco use, beliefs and risk awareness and psychosocial correlates of tobacco use among university students in 24 low, middle and emerging economy countries. Using anonymous questionnaires, data were collected from 16953 undergraduate university students (mean age 20.9, SD=2.9) from 25 universities in 24 countries across Asia, Africa and the Americas. Results indicate that overall 13.3% of the university students were current tobacco users, 22.4% for men and 6.6% for women, ranging from 3.8% in Singapore to 32.5% in Cameroon. The risk awareness of the smoking lung cancer link was 83.6%, while the risk awareness of the smoking heart disease link was 46.5%. Multivariate logistic regression found that older age, male gender, having a wealthy family background, living in a low income country, residing off campus on their own, poor beliefs in the importance not to smoke, awareness of the smoking heart disease link, hit by a sexual partner, depressive symptoms, and substance use (binge drinking and illicit drug use) were associated with current tobacco use.