• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.234-239
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• 2023

Waste from the food is a challenge to the environment all over the globe, hence there is need to be recycled. There is a great deal of renewable energy potential in the biomass of vegetables and fruits, which can be used to generate power and steam, as well as fuel for human consumption and laboratory solvents. To maintain the nutritional, antioxidative, and functional qualities of sapota fruit, wine was made by fermenting it with wine yeast (Saccharomyces cerevisiae). The wine's approximate composition was as follows: total soluble solids, 2.38°Brix; total sugar, 3.8 g/100 ml tartaric acidity (TA), 1.29 g tartaric acidity total phenolics, 0.21 g/100 mL; pH, 3.02; acid/100 mL; pH, 3.02; total phenolics, 0.21 g/100 mL; 22 g/100 ml -carotene; 1.78 g/100 ml ascorbic acid mg/100 ml; 0.64 mg/100 ml lactic acid; and The ethanol percentage is 8.23% (v/v). The sapota wine was delicious. A DPPH-scavenging 2, 2-diphenyl-1picryl hydroxyl (DPPH) at a dosage of 250 g/ml, the activity was 46%. Infrared alcohols, phenethylamines, and other compounds were discovered via spectroscopy.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.4
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• pp.11-23
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• 2023

In Korea, open burning of agricultural residues is prevalent due to inadequate collection systems, which have caused environmental impacts such as GHGs and particulates. This illegal treatment of agricultural residues also results in economic loss, considering that agricultural residues can be utilized as resources such as pellets and energy sources. To understand the effect of avoiding open burning, this study evaluated the economic, environmental, and social effects of two alternative management options for agricultural residues: incineration and pelletizing. The study estimates the potential amount and dry weight by region for 18 items, taking various factors into account. Regarding the economic aspect, pelletizing facilities in all regions in Korea create economic benefits. This study shows that most regions have an environmental advantage by pelletizing residues. However, incineration creates more environmental benefits than pelletizing in metropolitan cities with relatively low density of residues. It is expected that the environmental, economic, and social findings of this study can be used to inform policies for bioenergy as the need for agricultural residue increases.

• Parasites, Hosts and Diseases
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• v.52 no.2
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• pp.125-129
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• 2014

Several reports on taeniasis and cysticercosis in Vietnam show that they are distributed in over 50 of 63 provinces. In some endemic areas, the prevalence of taeniasis was 0.2-12.0% and that of cysticercosis was 1.0-7.2%. The major symptoms of taeniasis included fidgeted anus, proglottids moving out of the anus, and proglottids in the feces. Clinical manifestations of cysticercosis in humans included subcutaneous nodules, epileptic seizures, severe headach, impaired vision, and memory loss. The species identification of Taenia in Vietnam included Taenia asiatica, Taenia saginata, and Taenia solium based on combined morphology and molecular methods. Only T. solium caused cysticercosis in humans. Praziquantel was chosen for treatment of taeniasis and albendazole for treatment of cysticercosis. The infection rate of cysticercus cellulosae in pigs was 0.04% at Hanoi slaughterhouses, 0.03-0.31% at provincial slaughterhouses in the north, and 0.9% in provincial slaughterhouses in the southern region of Vietnam. The infection rate of cysticercus bovis in cattle was 0.03-2.17% at Hanoi slaughterhouses. Risk factors investigated with regard to transmission of Taenia suggested that consumption of raw meat (eating raw meat 4.5-74.3%), inadequate or absent meat inspection and control, poor sanitation in some endemic areas, and use of untreated human waste as a fertilizer for crops may play important roles in Vietnam, although this remains to be validated.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.763-766
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• 2007

국내에서 발생되는 고형폐기물 중 자원으로 재활용 가능한 유기성폐기물은 하수슬러지, 음식물류폐기물, 축산분뇨 등을 대표 할 수 있다. 이들 유기성폐기물은 환경적인 측면에서 볼 때 다른 유기성 폐수 및 폐기물에 비하여 오염부하량이 상대적으로 높지만, 이를 생물자원 (Biomass)으로 인식하고 이용 할 경우 지구온난화와 같은 환경문제 뿐만아니라 향후 자원고갈문제를 동시에 해결할 수 있는 대체에너지 자원이다. 유기성폐기물을 대체에너지 자원으로 효율적으로 이용하기 위해서는 우선적으로 국제적 환경규제와 에너지 정책에 능동적으로 대응할 수 있는 자원순환형 폐기물관리 시스템 구축이 필요하며, 이를 위한 체계적인 정책적 지원책과 기술 개발이 뒷받침 되어야 할 것이다. 자원 재활용과 에너지회수 기술에 있어 혐기성소화(anaerobic digestion)는 유기성폐기물의 효과적인 감량화, 재이용화, 안정화를 만족시키는 동시에 유용 에너지원인 메탄가스를 회수할 수 있는 바이오가스 전환기술로 최근에 주목을 받는 biotechnology 중의 하나로 자리매김 하고 있다. 특히, 소비자원의 대부분이 해외에 의존하는 국내현실과 최근 고유가에 따른 국가 에너지 정책을 제고해야하는 현 시점에서 유기성폐기물을 이용한 바이오가스화 기술을 널리 보급하기 위해서는 요소기술 개발과 정부의 적극적인 정책적 지원 방안이 마련되어야 할 것이다.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.4
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• pp.333-341
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• 2017

Recently, the earth has shown the limit of environmental capacity. It is also experiencing an environmental crisis with rising energy prices and depletion of coal. Therefore, development of renewable energy is very important solution. However, waste fuel solid are renewable fuels, but they cause environmental problems. In this study, the emission characteristics of hazardous air pollutants were analyzed through measurements at the facilities using solid fuels (SRF, BIO-SRF). Analysis method of PAHs are based on the Korea Standard Methods for Examination. The analysis of PAHs showed that the concentration much higher in Naphthalene, and Benzo(a)pyrene showed at a higher concentration incertain sources. As a result of gas phase and particle phase PAHs, most of Benzo(a)pyrene appeared to be particulate. Through the results of this study will provide basic data for atmospheric environmental management.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.271-275
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• 2005

Pine bark, chinese cabbage, crap shell which are used for removing metal ions from aqueous solutions. The removal of metal ions from aqueous solution by adsorption and ion exchange on bio residues was studied. Biosorption of $Cu^{2+},\;Ni^{2+},\;Pb^{2+}$ were compared. Adsorption ability different for the factors [adsorption time, adsorbent weight, initial concentration] and all experiments pH variation were investigated. It was shown that chinese cabbage has higher metal removal ability than other materials The pH variation of metal solution were investigated according to the influences of the initial concentration and weight adsorbents.

• Journal of Communications and Networks
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• v.17 no.5
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• pp.506-516
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• 2015

Wireless sensor networks (WSNs) are generally comprised of densely deployed sensor nodes, which results in highly redundant sensor data transmissions and energy waste. Since the sensor nodes depend on batteries for energy, previous studies have focused on designing energy-efficient medium access control (MAC) protocols to extend the network lifetime. However, the energy-efficient protocols induce an extra end-to-end delay, and therefore recent increase in focus on WSNs has led to timely and reliable communication protocols for mission-critical applications. In this paper, we propose an energy efficient and delay guaranteeing node scheduling scheme inspired by biological systems, which have gained considerable attention as a computing and problem solving technique.With the identification of analogies between cellular signaling systems and WSN systems, we formulate a new mathematical model that considers the networking challenges of WSNs. The proposed bio-inspired algorithm determines the state of the sensor node, as required by each application and as determined by the local environmental conditions and the states of the adjacent nodes. A control analysis shows that the proposed bio-inspired scheme guarantees the system stability by controlling the parameters of each node. Simulation results also indicate that the proposed scheme provides significant energy savings, as well as reliable delay guarantees by controlling the states of the sensor nodes.

• Environmental Engineering Research
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• v.24 no.2
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• pp.354-361
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• 2019

Renewable energy from biomass and biodegradable wastes can significantly supplement the global energy demand if properly harnessed. Pyrolysis is the most profound modern technique that has proved effective and efficient in the energy conversion of biomass to yield various products like bio-oil, biochar, and syngas. This study focuses on optimization of slow pyrolysis of banana peels waste to yield banana peels vinegar, tar and biochar as bio-infrastructure products. Response surface methodology using central composite design was used to determine the optimum conditions for the banana wastes using a batch reactor pyrolysis system. Three factors namely heating temperature ($350-550^{\circ}C$), sample mass (200-800 g) and residence time (45-90 min) were varied with a total of 20 individual experiments. The optimal conditions for wood vinegar yield (48.01%) were $362.6^{\circ}C$, 989.9 g and 104.2 min for peels and biochar yield (30.10%) were $585.9^{\circ}C$, 989.9 g and 104.2 min. The slow pyrolysis showed significant energy conversion efficiencies of about 90% at p-value ${\leq}0.05$. These research findings are of primary importance to Uganda considering the abundant banana wastes amounting to 17.5 million tonnes generated annually, thus using them as pyrolysis feedstock can boost the country's energy status.

• Composites Research
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• v.36 no.4
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• pp.264-269
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• 2023

Spent coffee grounds (SCG) are a ubiquitous byproduct of coffee consumption, representing a significant waste management challenge, as well as an untapped resource for economic development and sustainability. Improper disposal of SCG can result in environmental problems such as methane emissions and leachate production. This study aims to investigate the physicochemical properties of SCG and their potential as a reinforcement material in polypropylene (PP) to fabricate an eco-friendly composite via extrusion and injection molding, with SCG filler ratios ranging from 5-20%. To evaluate the effect of SCG on the morphological and mechanical properties of the bio- composite, thermogravimetric analysis, SEM, tensile, flexural, and impact tests were conducted. The results demonstrated that the addition of SCG lead to a slight increase in brittleness of the composite but did not significantly affect its mechanical properties. Impressively, the presence of a significant organic component in SCG contributed to the enhanced thermal performance of PP/SCG composites. This improvement was evident in terms of increased thermal stability, delayed onset of degradation, and higher maximum degradation temperature as compared to pure PP. These findings suggest that SCG has potential as a filler material for PP composites, with the ability to enhance the material's properties without compromising overall performance.

• Advances in nano research
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• v.14 no.1
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• pp.103-115
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• 2023

Recent developments in the synthesis of nanomagnesia of controlled sizes and shapes that are suitable for various applications are reviewed. Two main methods, based on liquid-phase synthesis, i.e., chemical methods and bio-based methods, are used to synthesize nanomagnesia. Conventionally, nanomagnesia was synthesized by chemical methods such as coprecipitation, sol-gel, combustion method, and so on using different chemical agents and stabilizers which later on become responsible for several biological risks because of the toxicity of used chemicals. Bio-based protocols are growing as another environmental friend method for the synthesis of various nanostructures especially nanomagnesia using biomass, plant extracts, alga, and fungi as a source of precursor material. The ideal method should offer better control of textural properties of nanostructures and decrease the necessity for purification of the synthesized nanoproducts, which sequentially removes the use of large amounts of chemicals and organic solvents and manipulation of products that are unsafe to the environment. Finally, the broad applicability of nanomagnesia in diverse areas is presented. Employment of nanomagnesia reported in several laboratory and industrial fields are valued from the standpoint of the significance of these issues for technological requests, as described in the literature. Nanomagnesia has various applications such as antimicrobial performance, removing pollutants, batteries application, and catalysis.