Decomposition analysis of oil export dependency: a case study of Mexico, Indonesia and Nigeria

Nnaemeka Vincent Emodi,Kyung-Jin Boo 한국자원공학회 2016 Geosystem engineering Vol.19 No.1

This paper investigated the oil export dependency of Mexico, Indonesia and Nigeria, which are major oil-producing countries in their respective geographical regions, and how their oil export have evolved over the last two decades. Oil export importance was analysed by relating it to the effective export price, oil export importance, oil dependence and energy intensity of Mexico, Indonesia and Nigeria for the period 1986–2010. The trends were analysed for Mexico, Indonesia and Nigeria, while the decomposition result showed that price effect had the most influential factors to revenue changes in the three countries. Indonesia and Nigeria were less oil export intensive in the last period, 2001–2010, and the three countries had an improvement in their energy efficiency due to a decrease in energy intensity. The authors recommend that energy efficiency improvements and reduction in oil export dependence, with the diversification of export will improve the country’s revenue and safeguard their economies against decline in oil prices.

RENEWABLE ENERGY IN NEPAL

Nnaemeka Vincent Emodi,Kyung-Jin Boo 한국신재생에너지학회 2015 AFORE Vol.2015 No.11

SUSTAINABLE ENERGY DEVELOPMENT IN NIGERIA

Nnaemeka Vincent EMODI,Kyung-Jin BOO 한국신재생에너지학회 2014 AFORE Vol.2014 No.-

POLICY SCENARIOS FOR LOW CARBON ENERGY DEVELOPMENT IN NIGERIA

Nnaemeka Vincent EMODI 한국신재생에너지학회 2015 AFORE Vol.2015 No.11

Friction Assessment of Canola Oil on Contact Bearing Materials

Nicholas Nnaemeka Okechukwu,JaeYoung Byun,JongSoon Kim,JongMin Park,SoonGoo Kwon,SungWon Chung,SoonHong Kwon,WonSik Choi 한국트라이볼로지학회 2020 한국윤활학회지(윤활학회지) Vol.36 No.1

In manufacturing operations, oil plays a crucial role in reducing friction and wear among interacting surfaces at varying velocities, loads, and temperature. Hydrocarbon oil is considered the origin of lubrication oils. However, this base oil has been limited in its use as it is a principal cause of pollution. This research focuses on identifying a biodegradable base oil lubricant that possesses a stable coefficient of friction and viscosity with temperature. Friction analysis is conducted by employing a pin on a disk tribotester with a fixed load of 10 N at varying sliding speeds ranging from 0.06 m/s to 0.34 m/s. Oil viscosity analysis is perfomed at room temperature by using a rotary viscometer. Tests are performed using canola oil and paraffin oil as lubricants. The results indicate that the viscosity of canola oil is more efficient than paraffin oil. The non-dimensional characteristic number according to the Stribeck curve reveals an elastohydrodynamic lubrication regime with canola oil lubrication. A comparison of both lubricants reveals that, the friction efficiency of canola oil and paraffin oil does not differ considerably. However, the friction in canola oil is observed to decrease more than that in paraffin oil at an elevated sliding speed. The tests confirm that canola oil is potent in minimizing the friction coefficient of SCM440 bodies interacting with one another as well as acted upon by load.

Development of SSR for foxtail millet (Setaria italica (L.) P. Beauv.) and its utility in genetic discrimination of a core set

Oscar Nnaemeka Obidiegwu,Jude Ejikeme Obidiegwu,Heiko Parzies 한국유전학회 2013 Genes & Genomics Vol.35 No.5

Foxtail millet (Setaria italica (L.) P. Beauv.) is an underutilized food and forage crop with immense potential in improving global food security. In this study sequence data were mined at the database of NCBI with the aim of developing polymorphic nucleotide and expressed sequence tags (ESTs) simple sequence repeat markers. Successful amplification was visualized on 3 % agarose gel. The selected 12 candidate markers were further used to characterize available 155 core collections. A total number of 198 alleles with an average of 16.5 alleles per loci were discovered. Heterozygosity (H) ranged between 0.05 (UHSi-173) to 0.23 (UH-Si-487) with a mean average of 0.16. Gene diversity ranged from 0.15 (UHSi-766) to 0.96 (UHSi-500), with an average value of 0.80 across the populations. The polymorphic information content (PIC) ranged from 0.15 (UH-Si-766) to 0.96 (UH-Si-500) with a mean value of 0.79. A positive correlation (r = 0.720; P\0.01) was found between the PIC and the number of alleles. Weighted neighbor joining dendrogram generated seven major clusters. More polymorphism was detected with the nucleotides derived microsatellites when compared to the ESTs derived microsatellites. This result shows that the morphological and phenotypic descriptors used for the development of the 155 core collections of foxtail millet was optimal enough to capture as much diversity. The newly developed markers in this study are quite informative and recommended for future genetic studies in the species and close related genera.

Friction Characteristics of Aluminized Polyester Fabric under Dry - and Water- Lubricated Conditions

JaeYoung Byun,Nicholas Nnaemeka Okechukwu,Eunsuk Lee,JinGyu Park,WonSik Choi 한국트라이볼로지학회 2019 한국윤활학회지(윤활학회지) Vol.35 No.6

Materials made from plastics are increasingly utilized in constructing greenhouses and setting up shield structures. Polyester fabrics have a wide range of use in horticulture and other fields of agriculture. They are utilized as a greenhouse cover and also help in combating intense climate variation in the field. Over time, these fabrics may experience friction against other surfaces. Owing to this, the surface framework of the material degenerates. This study examines the frictional characteristics of aluminized polyester fabric in both dry- and water-lubricated environments under changing applied loads and sliding speeds. Friction experiments are performed at room temperature by employing a pin on a disk. The experiments reveal that the friction coefficient decreases with increase in applied load in both dry sliding and water-lubricated environment. However, the friction coefficient decreases more under the water-lubricated setting than in the dry state. At the maximum applied load, the highest friction coefficient is discovered in the dry state with a range of 0.282 to 0.237, whereas a friction coefficient of 0.229 to 0.189 is observed in the water-lubricated state. Additionally, it is observed that the friction coefficient increases with an increase in sliding speed under both experimental environments. The examination of specimen surfaces reveals that the abrasion is minor in the water-lubricated setting compared with that in the dry state.

Friction Characteristics of Aluminized Polyester Fabric under Dry - and Water- Lubricated Conditions

Byun, JaeYoung,Okechukwu, Nicholas Nnaemeka,Lee, Eunsuk,Park, JinGyu,Choi, WonSik Korean Tribology Society 2019 한국트라이볼로지학회지 (Tribol. Lubr.) Vol.35 No.6

Materials made from plastics are increasingly utilized in constructing greenhouses and setting up shield structures. Polyester fabrics have a wide range of use in horticulture and other fields of agriculture. They are utilized as a greenhouse cover and also help in combating intense climate variation in the field. Over time, these fabrics may experience friction against other surfaces. Owing to this, the surface framework of the material degenerates. This study examines the frictional characteristics of aluminized polyester fabric in both dry- and water-lubricated environments under changing applied loads and sliding speeds. Friction experiments are performed at room temperature by employing a pin on a disk. The experiments reveal that the friction coefficient decreases with increase in applied load in both dry sliding and water-lubricated environment. However, the friction coefficient decreases more under the water-lubricated setting than in the dry state. At the maximum applied load, the highest friction coefficient is discovered in the dry state with a range of 0.282 to 0.237, whereas a friction coefficient of 0.229 to 0.189 is observed in the water-lubricated state. Additionally, it is observed that the friction coefficient increases with an increase in sliding speed under both experimental environments. The examination of specimen surfaces reveals that the abrasion is minor in the water-lubricated setting compared with that in the dry state.

시설재배용 첨단 표고버섯 재배시스템 연구

변재영 ( Jae Young Byun ),오케추쿠나에메카니콜라스 ( Okechukwu Nnaemeka Nicholas ),이은숙 ( Eun Suk Lee ),양지웅 ( Ji Ung Wang ),김국현 ( Kuk Hyeon Kim ),김근우 ( Geun Woo Kim ),박진규 ( Jin Gyu Park ),최원식 ( Won Sik Choi ) 한국농업기계학회 2019 한국농업기계학회 학술발표논문집 Vol.24 No.1

기후가 급격히 변함에 따라 농작물의 생산환경이 급변하고 있으며, 폭설, 폭우, 혹서 등의 환경에 대해 독립된 환경을 조성하고자 스마트팜이 화두가 되고 있다. 더불어 인구고령화와 노동력 부족, 생산성 효율 등의 문제로 식물공장을 통한 무인재배 환경을 만들기 위해 다양한 시도가 이루어지고 있다. 국내에서는 비닐하우스와 유리온실이 주로 사용되고 있으며 무인 환경을 조성하기 위해서 비닐하우스는 겨울철 난방문제와 유리온실의 여름철 고온에 대한 냉방 문제를 해결해야 한다. 작물 및 지역 조건에 맞는 냉난방 온도를 효율적으로 제어할 수 있는 시스템 구축이 필요하다. 이에 본 논문에서는 온·습도 변화에 민감한 표고버섯을 이용하였으며, 품질안정화와 노동력 저감, 수확량 증가를 위해 수직형 체인 컨베이어 형식의 재배사와 생육 관수 및 습도, 조명, 이산화탄소를 무인으로 제어할 수 있는 스마트팜 환경제어 시스템을 제안한다. 재배사에 부착된 각종 센서를 통해 실시간으로 수분 공급 및 환기를 통해 버섯의 생육하는 데 최적화된 상태를 제공한다. 이를 통해 기존에 시행되고 있는 재래식 방식의 버섯재배사의 문제점인 상하의 상태차이로 인한 품질이 균일하지 못한 점을 해소하고 컨베이어 형식으로 사용자의 노동력 및 시간관리에 도움을 줄 수 있다. 또한 동일한 공간 활용 시 기존의 재배사 보다 높은 생산량을 확보 할 수 있다.

Use of Seawater and Pesticides (Geunsami and Pullmagi Gold) for Suppressing Growth of Spartina anglica and Their Effects on Soil Stability

이은숙,변재영,Maynanda Brigita Chrysta,Okenkwu Nnaemeka Nicholas,이세용,최원식 사단법인 미래융합기술연구학회 2020 아시아태평양융합연구교류논문지 Vol.6 No.2

Common cordgrass (Spartina anglica) is a harmful marine organism that has proved to be a serious invasive species causing extensive damage to natural saltmarsh ecosystems in many areas. In order to reduce the damage that may occur from spreading these plants, it takes the best steps to destroy them. In this study, an experiment of Spartina anglica growth suppression was carried out. The media used to eradicate these weeds were seawater concentrate and pesticides (Pullmagi gold and Geunsami). In testing Spartina anglica and clover growth inhibition, samples were planted in mudflats A, B, and C. In mudflats (A) sprayed seawater concentrate using 5L stock solution, (B) sprayed 5L liquid herbicide and 25ml pesticides, and (C) sprayed liquid herbicide 5L and 50ml pesticides. As a result, after 5 days of spraying, the growth inhibition of the sliding plant showed that variation (A) with seawater concentrate showed rapid growth inhibition, while for variation (B) and (C) that using herbicides did not show growth inhibition. The change in growth inhibition on variation A was remarkable. The seawater concentrate showed growth inhibition of whole leaves after 1 day. The results of the five heavy metals analysis of soils were also not detected and the growth inhibition and safety of plants after the experiments are analyzed in the sludge and seagrass of sea soils.