• Title/Summary/Keyword: OIL

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EU Enlargement and economic environmental change of Russia and Eastern Europe - From asymmetry and subsidiarity paradigm in industrial cooperative paradigm (EU의 동방확대에 따른 동유럽·러시아간의 경제 환경 변화 - 비대칭성 및 보완성 패러다임에서 산업협력 패러다임으로)

  • Kim, Sang Won
    • Journal of International Area Studies (JIAS)
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    • v.13 no.1
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    • pp.135-156
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    • 2009
  • The two waves of EU enlargement in 2004 and 2007, have been milestones of European integration. While research has been conducted into the impact of these events on both the European and the global economies,1 there have been few attempts to assess the effects of EU enlargement and the introduction of the euro on countries such as Russia, which neighbour the EU but currently have no perspective of accession. This paper aims to provide an assessment of the effects that EU enlargement and the introduction of the euro have had on Russia, the largest country neighbouring the EU. In particular, it focuses on trade and investment links between the EU and Russia, as well as the use of the energy by Russian residents and authorities. Economic links between Russia and the EU are found to have strengthened considerably in the areas of trade, investment and other financial flows in recent years. Strong growth, particularly in Russia, as well as the high price of oil and gas, Russia's major export items, has facilitated this expansion of trade and finance. Moreover, available data do not suggest that EU enlargement has had a negative impact on Russia in terms of trade or investment diversion. Thus, the strategic partnership between Russia and the EU has been increasingly underpinned by an expansion of cross-border economic activities. Thus, the paper contributes to two broad strands of literature on this subject, namely the impact of regional trade and economic arrangements on non-member countries and the international role of currencies.

Synthesis of High-purity Silicon Carbide Powder using the Silicon Wafer Sludge (실리콘 기판 슬러지로부터 고순도 탄화규소 분말 합성)

  • Hanjung Kwon;Minhee Kim;Jihwan Yoon
    • Resources Recycling
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    • v.31 no.6
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    • pp.60-65
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    • 2022
  • This study presents the carburization process for recycling sludge, which was formed during silicon wafer machining. The sludge used in the carburization process is a mixture of silicon and silicon carbide (SiC) with iron as an impurity, which originates from the machine. Additionally, the sludge contains cutting oil, a fluid with high viscosity. Therefore, the sludge was dried before carburization to remove organic matter. The dried sludge was washed by acid cleaning to remove the iron impurity and subsequently carburized by heat treatment under vacuum to form the SiC powder. The ratio of silicon to SiC in the sludge was varied depending on the sources and thus carbon content was adjusted by the ratio. With increasing SiC content, the carbon content required for SiC formation increased. It was demonstrated that substoichiometric SiCx (x<1) was easily formed when the carbon content was insufficient. Therefore, excess carbon is required to obtain a pure SiC phase. Moreover, size reduction by high-energy milling had a beneficial effect on the suppression of SiCx, forming the pure SiC phase.

Study on Skin Permeation of Tocopheryl Acetate Using Swollen Micelle (Swollen Micelle을 이용한 Tocopheryl Acetate 의 피부흡수 연구)

  • Su-Bin Son;Kyung-Sup Yoon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.1
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    • pp.17-27
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    • 2023
  • A study was performed to increase skin permeation of tocopheryl acetate, an oil-soluble component among tocopheryl acetate, salicylic acid, and niacinamide, which are the active ingredients of the anti-hair loss toner. As a method of transparently solubilizing tocopheryl acetate while containing salicyl acid and niacinamide, we used a swollen micelle structure that increased the size of the micelle formed by the aggregation of surfactants. The prepared swollen micelle solution contains three kinds of active ingredients, and poloxamer 407 and octyldodeceth-16 were used as surfactants to increase transparent properties and stability. In addition, isostearic acid was used as a co-surfactant to increase the size of micelles. To evaluate the physical properties of the prepared swollen micelles, turbidity at room temperature (25 ℃) was measured. The Franz diffusion cell method was used to evaluate the skin permeation rate of tocopheryl acetate among the hair-loss prevention components contained in swollen micelles. After 24 h, tocopheryl acetate showed a 6-fold improvement in skin permeation compared to the control group. Therefore, it can be seen that the swollen micelles developed in this study can be applied to hair-loss prevention products or solubilized formulations of various functional cosmetics.

Experimental Assessment of the Methanol Addition Effect on the Tribological Characteristics of Ni-based Alloy (메탄올 첨가에 따른 Ni 기반 합금의 트라이볼로지 특성 변화에 대한 실험적 연구)

  • Junemin Choi;Sangmoon Park;Youngjun Kim;Sunghoon Kim;Hyemin Kim;Jeongeon Park;JeongWon Yu;Myeonggyu Lee;Hyeonwoo Lee;Koo-Hyun Chung
    • Tribology and Lubricants
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    • v.39 no.2
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    • pp.49-55
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    • 2023
  • Currently, the demand for green technologies toward a sustainable future is rapidly increasing due to growing concern over environmental issues. Methanol is biodegradable and can provide clean combustion to reduce sulfur oxide and nitrogen oxide emissions, and therefore it is a candidate fuel for marine engines. However, the effect of methanol on tribological characteristic degradation should be addressed for methanol-fueled engines. In this study, the methanol addition effects on tribological characteristic degradation is experimentally assessed using a pin-on-disk tribo-tester. Ni-based alloy is used as a target material due to its broad applicability as an engine component material. For a lubricant, engine oil with and without methanol are used. The tests are conducted for up to 10,000 cycles under boundary lubrication while the change in friction force is monitored. Additionally, the wear rate is determined based on laser scanning confocal microscope data. An additional test in which methanol is added at regular intervals is performed with an aim to directly observe its effect on friction. Overall, the friction coefficient increases slightly with increasing methanol concentration. Furthermore, the wear rate of the pin and disk increase significantly with methanol addition. The results also indicate that the friction increases instantaneously with methanol addition at the contacting interface. These findings may be useful for better understanding the methanol effect on the tribological characteristics of Ni-based alloys for methanol-fueled engines with improved performance.

Soil Health Assessment of Soil Washing and Landfarming Treated Soils (토양세척 및 토양경작 정화 토양의 건강성 평가)

  • Yong min Yi;Kijune Sung
    • Journal of Environmental Impact Assessment
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    • v.32 no.2
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    • pp.112-122
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    • 2023
  • To restore the ecological function of contaminated soil and maximize the ecological services provided by the soil, besides the toxicity orrisk caused by pollutants, the functional aspects of the soil ecosystem should be considered. In this study, a method for evaluating the health of cleaned soil was presented, and the applicability of the proposed evaluation method was examined by applying it to soil treated with washing and landfarming. Productivity, habitat, water retention capacity, nutrient cycling, carbon retention capacity, and buffering capacity were used as soil health evaluation indicators. The results showed that the soil health was not completely recovered after remediation, and even in the case of the washed soil, the health was lower than before remediation. On the other hand, there was no significant change in soil quality due to oil pollution, but soil health deteriorated. Unlike the slightly improved soil quality after landfarming treatment, soil health was not completely restored. Therefore, the results of this study indicate that it is desirable to consider both soil quality and health when evaluating the remediation effect. The soil health evaluation method proposed in this study can be usefully utilized for the sustainable use of cleaned soil and to promote ecosystem services.

Recent Research Trends in Antibacterial, Antifungal, and Antiviral Active Packaging (항균, 항진균 및 항바이러스 액티브 패키징의 최근 연구 동향)

  • Siyeon Park;Hani Ji;Jieun Choi;Seulgi Imm;Yoonjee Chang
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.29 no.1
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    • pp.15-25
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    • 2023
  • Since the COVID-19 crisis, the use of disposable packaging materials and delivery services, which raise environmental and social issues with waste disposal, has significantly increased. Antimicrobial active packaging has emerged as a viable solution for extending the shelf-life of foods by minimizing microbial growth and decomposition. In this review article, we provide a comprehensive overview of current research trends in antimicrobial active film and coating published over the last five years. First, we introduced various polymer materials such as film and coating that are used in active packaging. Next, various types of antimicrobial (antibacterial, antifungal, and antiviral) packaging including essential oil, extracts, biological material, metal, and nanoparticles were introduced and their activities and mechanisms were discussed. Finally, the current challenges and prospects were discussed. Overall, this review provides insights into the recent advancements in antimicrobial active packaging research and highlights the potential of the technology to enhance food safety and quality.

Effects of Foot Bath and Spray Application of Peppermint and Grapefruit Essential Oils on Lower Extremity Edema, Pain, and Fatigue (페퍼민트, 그레이프후룻 에센셜 오일을 이용한 족욕 또는 스프레이 적용이 하지부종, 통증 및 피로에 미치는 효과)

  • Han, Ari;Kim, Juri;Hur, Myung-Haeng
    • Journal of the Korea Convergence Society
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    • v.13 no.1
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    • pp.375-386
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    • 2022
  • Work involving standing or walking for a long time can cause swelling, pain, and fatigue in the lower extremities due to the effect of gravity on the circulation of the body. This study aimed to confirm the effects of aromatherapy essential oils, as a complementary and alternative therapy, on lower extremity edema, pain, and fatigue when applied as a foot bath or spray. The study was conducted after daytime work over two consecutive days on nurses who volunteered at the E University Hospital in D Metropolitan city between 15 August 2018 and 11 October 2018. This randomized controlled study. The foot bath group received a foot bath in 9 L of water containing 0.5 ml of essential oil blended with grapefruit and peppermint in a 1:1 ratio. The spray group received the same solution in 3% dilution in the form of a spray. Edema was assessed by measuring calf and ankle circumference, while pain and fatigue were evaluated using a numerical rating scale. Data were analyzed by ANOVA and repeated-measures ANOVA. The calf circumference in the foot bath and spray groups significantly reduced compared to that in the control group (F = 14.053, p <.001) after the interventions. Lower extremity pain (F = 42.497, p < .001) and fatigue (F = 20.641, p < .001) also significantly reduced in the foot bath and spray groups compared to those in the control group after the interventions. Foot bath is recommended to relieve swelling and pain in the lower extremities, and aroma spray is highly recommended considering the ease of application.

Plane-wave Full Waveform Inversion Using Distributed Acoustic Sensing Data in an Elastic Medium (탄성매질에서의 분포형 음향 센싱 자료를 활용한 평면파 전파형역산)

  • Seoje, Jeong;Wookeen, Chung;Sungryul, Shin;Sumin, Kim
    • Geophysics and Geophysical Exploration
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    • v.25 no.4
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    • pp.214-216
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    • 2022
  • Distributed acoustic sensing (DAS), an increasingly growing acquisition technique in the oil and gas exploration and seismology fields, has been used to record seismic signals using optical cables as receivers. With the development of imaging methods for DAS data, full waveform inversion (FWI) is been applied to DAS data to obtain high-resolution property models such as P- and S-velocity. However, because the DAS systems measure strain from the phase distortion between two points along optical cables, DAS data must be transformed from strain to particle velocity for FWI algorithms. In this study, a plane-wave FWI algorithm based on the relationship between strain and horizontal particle velocity in the plane-wave assumption is proposed to apply FWI to DAS data. Under the plane-wave assumption, strain equals the horizontal particle velocity, which is scaled by the velocity at the receiver position. This relationship was confirmed using a numerical experiment. Furthermore, 4-layer and modified Marmousi-2 velocity models were used to verify the applicability of the proposed FWI algorithm in various survey environments. The proposed FWI was implemented in land and marine survey environments and provided high-resolution P- and S-velocity models.

A Review of Seismic Full Waveform Inversion Based on Deep Learning (딥러닝 기반 탄성파 전파형 역산 연구 개관)

  • Sukjoon, Pyun;Yunhui, Park
    • Geophysics and Geophysical Exploration
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    • v.25 no.4
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    • pp.227-241
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    • 2022
  • Full waveform inversion (FWI) in the field of seismic data processing is an inversion technique that is used to estimate the velocity model of the subsurface for oil and gas exploration. Recently, deep learning (DL) technology has been increasingly used for seismic data processing, and its combination with FWI has attracted remarkable research efforts. For example, DL-based data processing techniques have been utilized for preprocessing input data for FWI, enabling the direct implementation of FWI through DL technology. DL-based FWI can be divided into the following methods: pure data-based, physics-based neural network, encoder-decoder, reparameterized FWI, and physics-informed neural network. In this review, we describe the theory and characteristics of the methods by systematizing them in the order of advancements. In the early days of DL-based FWI, the DL model predicted the velocity model by preparing a large training data set to adopt faithfully the basic principles of data science and apply a pure data-based prediction model. The current research trend is to supplement the shortcomings of the pure data-based approach using the loss function consisting of seismic data or physical information from the wave equation itself in deep neural networks. Based on these developments, DL-based FWI has evolved to not require a large amount of learning data, alleviating the cycle-skipping problem, which is an intrinsic limitation of FWI, and reducing computation times dramatically. The value of DL-based FWI is expected to increase continually in the processing of seismic data.

A Study of a Pilot Test for a Blasting Performance Evaluation Using a Dry Hole Charged with ANFO (건공화 공법의 발파 성능 평가를 위한 현장 시험에 관한 연구)

  • Lee, Seung Hun;Chong, Song-Hun;Choi, Hyung Bin
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.2
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    • pp.197-208
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    • 2022
  • The existence of shallow bedrock and the desire to use underground space necessitate the use of blasting methods. The standard blasting method under water after drilling is associated with certain technical difficulties, including reduced detonation power, the use of a fixed charge per delay, and decoupling. However, there is no blasting method to replace the existing blasting method. In this paper, a dry hole charged with ANFO blasting is assessed while employing a dry hole pumping system to remove water from the drill borehole. Additional standard blasting is also utilized to compare the blasting performances of the two methods. The least-squares linear regression method is adopted to analyze the blasting vibration velocity quantitatively using the measured vibration velocity for each blasting method and the vibration velocity model as a function of the scaled distance. The results show that the dry hole charged with ANFO blasting will lead to greater damping of the blasting vibration, more energy dissipation to crush the surrounding rock, and closer distances for the allowable velocity of the blasting vibration. Also, standard blasting shows much longer influencing distances and a wider range of the blasting pattern. The pilot test confirms the blasting efficiency of dry hole charged with ANFO blasting.