The study examined the impact of single parenthood on adolescents’ academic performance in secondary schools in Owode Local Government Area of Mowe, Ogun State, Nigeria. In this study, relevant and extensive literatures were reviewed under relevant sub-headings. The descriptive research survey was used to assess the respondents’ opinions using the questionnaire. In this study, 130 (one hundred and thirty) respondents were selected through simple random technique and used as samples to represent the population of the study. A total of three (3) null hypotheses were formulated and tested in this study. Also, the independent t-test statistical tool was used to test and analyse the null hypotheses at 0.05 level of significance. The three hypotheses were tested and accepted to have significant importance on adolescents’ academic performance.

This study empirically examined the effect of female director on tax aggressiveness of listed insurance firms in Nigeria. The main objective of this research was to empirically investigate the effect of female board members on tax aggressiveness, determine the composition and representation of female directors on the board of insurance companies, find out how tax aggressive are listed insurance firms and apply the BLAU (1977) index method to measure female director representation as a departure from conventional approaches specifically in the Nigerian context in the reference period, 2014 to 2018. The population of the study consists of all the quoted insurance firms as at 31st December, 2016. A sample of twenty eight (28) quoted insurance firms was selected and data were collected over the period. Inferential statistic consisting of the General Method of Moment was used for the data analysis. The results obtained reveal that board size is negative and exerts significant impact on tax aggressiveness in insurance firms in Nigeria. The study therefore recommends that the Federal government has to come up with a policy to respond to the marginalization of female on the insurance firm corporate board in Nigeria. The aim of this policy thrust should be targeted at reducing politics and biasness against women on the corporate boards of listed insurance firms.

The purpose of this paper is to compare seafarers’ behavior according to traffic conditions of a road and an onshore locations. Behaviors are classified into three categories: Skill-, Rule- and knowledge-based mode. Experimental data were collected using the questionnaires for navigators, working in a merchant ship. To compare the behaviors, we used the four analysis method; the degree of frequency, reliability test, correlation and linear regression. As a result of the study, it was found that Skill-based behavior shows more higher in the road traffic than the maritime traffic, and rule-based behavior shows more higher in the maritime traffic than the road traffic. Also, the behavior in the navigation situation showed statistical significance. Especially, in the case of Rule-based behavior, a high correlation between road and maritime was found. This study can be expected to apply to complementary system utilization between error management system of onshore and maritime traffic.

A triple-layered PMMA/Ni64Zr36/PDMS hydrogen gas sensor using hydrogen permeable alloy and flexible polymer layers is fabricated through spin coating and DC-magnetron sputtering. PDMS(polydimethylsiloxane) is used as a flexible substrate and PMMA(polymethylmethacrylate) thin film is deposited onto the Ni64Zr36 alloy layer to give a high hydrogenselectivity to the sensor. The measured hydrogen sensing ability and response time of the fabricated sensor at high hydrogen concentration of 99.9 % show a 20 % change in electrical resistance, which is superior to conventional Pd-based hydrogen sensors, which are difficult to use in high hydrogen concentration environments. At a hydrogen concentration of 5 %, the resistance of electricity is about 1.4 %, which is an electrical resistance similar to that of the Pd77Ag23 sensor. Despite using low cost Ni64Zr36 alloy as the main sensing element, performance similar to that of existing Pd sensors is obtained in a highly concentrated hydrogen atmosphere. By improving the sensitivity of the hydrogen detection through optimization including of the thickness of each layer and the composition of Ni-Zr alloy thin film, the proposed Ni-Zr-based hydrogen sensor can replace Pd-based hydrogen sensors.

One- and two-dimensional carbon nanomaterials were tested as adsorbents for the elimination of two anionic dyes, reactive red 2 and methyl orange, and the cationic dye methylene blue from aqueous solutions under the same conditions. Carbon nanomaterials performed well in the removal of dyes. Surface oxygenated groups in the nanomaterials improved the cationic dyes’ adsorption, but not the adsorption of the anionic dye. The interactions between nanomaterials and dyes were verified by infrared and Raman spectroscopy. The pseudo-second order kinetic model was better fitted to the kinetic experimental data than the Elovich and pseudo-first order models. The equilibrium adsorption data were best fitted by the Langmuir model. The dimensions and morphology of the carbon nanomaterials play an important role in the adsorption of the three dyes. The main mechanism of adsorption of anionic dyes is by the interactions of the aromatic rings of the dye structures and π delocalized electrons on carbon nanostructures; the adsorption of cationic dye is mainly due to electrostatic interactions.

Lignocellulosic materials such as agricultural residues have been identified as potential sustainable sources that can replace petroleum-based polymers. This study focused on the conversion of lignin extracted from bagasse to carbon fiber (CF) and cellulose nanocrystal (CNC). The highest extraction of lignin yield was achieved at 100 °C using 10% NaOH for 12 h. Carbon fibers were obtained by electro-spinning of bagasse lignin blended with polyvinyl alcohol (PVA) (11 wt/v %) followed by thermo-stabilization (250 °C) in an oxidizing atmosphere and further carbonization in an inert atmosphere (850 °C). Conventional hydrolysis process was used to extract cellulose nanocrystal from bagasse pulp. Morphological (scanning electron microscopy, SEM), spectral (Fourier transform infrared, FTIR) spectroscopy, elemental analysis, thermal characterization and surface area measurements have been carried out. Figures originated by SEM showed that CF ranges from 145 to 204 nm, while stabilized bagasse cellulose nanocrystal (SCNC) appeared as rod-shape like structure in the range of length 600–800 nm and diameter 5.33–19 μm. Characterization results revealed that CF exhibits microporous structure, while bagasse lignin and SCNC display mesoporous structure. In addition, the results proved that SCNC exhibits a percentage removal 71.56% for methylene blue dye in an aqueous solution.

한국원자력연구원 부지 내에 위치한 지하처분연구시설(KAERI Underground Research Tunnel, KURT) 에서는 선진핵주기 고준위폐기물처분시스템(A-KRS)을 기반으로 고준위방사성폐기물을 처분하였을때, 예상되는 공학적방벽(Engineered Barrier System, EBS)과 자연방벽(Natural Barrier System, NBS)에서의 열-수리-역학적 복합거동(Thermo-Hydro-Mechanical coupled behavior)의 특성을 규명하고자 현장시험(In-situ Demonstration of Engineered Barrier System, In-DEBS)을 2012년부터 계획 및 설계를 시작하여, 2016년 5월부터 지하처분연구시설 3번 연구 갤러리(Research gallery 3)에서 진행하고 있다. 현장시험의 데이터를 분석하고 열-수리-역학적 복합거동 특성을 명확히 규명하기 위해서는 경주 벤토나이트와 KURT 암석 및 암반의 열적, 수리적, 그리고 역학적 물성 특성을 반드시 파악하고 있어야만 한다. 이에 본 연구에서는 지금까지 수행된 KURT 부지 특성과 KURT 화강암 및 경주 벤토나이트의 열적, 수리적, 그리고 역학적 특성을 정리하고, 열적, 수리적, 그리고 역학적 모델을 제시하였다. 특히, 온도에 따른 암석의 열팽창계수 변화, 응력에 따른 암석의 투수계수 변화, 포화도에 따른 벤토나이트 및 암석의 열전도도 변화, 포화도에 따른 벤토나이트의 비열 및 흡입력 변화와 같은 열-수리-역학적 복합물성에 대한 다양한 모델을 도출함으로써, In-DEBS 현장시험 결과 분석과 열-수리-역학적 복합거동 특성 평가를 위해 수행 될 수치시험에 필요한 벤토나이트와 암석 및 암반의 입력자료를 제시하고자 하였다.

The New Vacuum Solar Telescope (NVST) is the largest solar telescope in China. When using CCDs for imaging, equal-thickness fringes caused by thin-film interference can occur. Such fringes reduce the quality of NVST data but cannot be removed using standard flat fielding. In this paper, a correction method based on multi-scale decomposition and adaptive partitioning is proposed. The original image is decomposed into several sub-scales by multi-scale decomposition. The region containing fringes is found and divided by an adaptive partitioning method. The interference fringes are then filtered by a frequency-domain Gaussian filter on every partitioned image. Our analysis shows that this method can effectively remove the interference fringes from a solar image while preserving useful information.