• Review of KIISC
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• v.19 no.5
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• pp.68-72
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• 2009

최근 들어 기학급수적으로 증가하는 방송 및 통신 시스템으로 인해 무선 주파수 자원의 고갈 문제가 심각하게 대두되고 있다. 이와 같은 주파수 고갈과 비효율적인 주파수 사용 문제를 해결하기 위해 유휴 주파수를 합리적으로 이용하기 위한 인지무선(Cognitive radio) 기술이 많은 관심을 받고 있다. 본 고에서는 TV 주파수 대역 내 유휴자원(White space)을 대상으로 주파수 공유 기술인 인지무선 기술을 적용하기 위해 현재 표준화가 진행 중인 IEEE 802.22 WRAN을 중심으로 인지 무선네트워크를 위한 보안 표준화 현황을 살펴본다.

• 비료회보
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• s.123
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• pp.28-38
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• 1979

• Nuclear industry
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• v.6 no.9 s.43
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• pp.4-5
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• 1986

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.57-58
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• 2003

현재, 우리나라 주변해역에 있어서는 어업자원의 고갈현상이 급속히 진행되고 있고, 어업자원을 간접적으로 자원을 관리하던 방법에서 직접적으로 관리하기 위한 총 허용어획량(TAC, Total Allowable Catch) 제도를 도입하기에 이르렀다. 이들 어족 자원을 보다 효율적이고 지속적으로 관리하기 위해서는, 어류의 체장추정에 필요한 음향반사강도의 data bank를 구축하는 것이 시급하다. (중략)

• Life and Agrochemicals
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• v.26 no.5 s.208
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• pp.52-55
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• 2005

• JOURNAL OF ELECTRICAL WORLD
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• no.1 s.37
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• pp.51-56
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• 1980

세계적으로 고갈되어 가는 자원, 특히 석유자원으로 말미암아 각국의 에너지 정책은 초비상에 걸려 있다. 금번호에는 일본 ${\ulcorner}Energy{\lrcorner}$지에서 오스트랄리아와 스웨덴의 에너지정책을 발췌${\cdot}$수록한다.

• Journal of the KSME
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• v.56 no.12
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• pp.37-41
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• 2016

인간의 삶은 자연에서 온다. 이 자연을 어떻게 이용하느냐는 자원 잉여의 시대를 지나 자원 고갈의 시대에 접어든 우리에게 근원적인 질문이다. 이 질문에 대하여 오랜 진화의 산물인 생명체의 효율적인 삶의 방식에서 답을 찾고자 한다.

• Clean Technology
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• v.15 no.3
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• pp.224-230
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• 2009

Life Cycle Assessment (LCA) has been studied on the reuse of glass bottles. The system boundary in this study encompassed from gate to gate such as production and transportation. A 360 mL volume of a glass bottle was selected as the functional unit. The environmental impact assessments was studied on 6 categories including abiotic resource depletion, acidification, eutrophication, global warming, ozone depletion, and photochemical oxidant creation. The results showed that the most significant impact categories were abiotic resource depletion (48.63%) and global warming (46.27%), and the rest categories revealed insignificant impacts. In the whole system, the chemicals used for the new bottle production revealed the major contribution to the environmental impacts (71.24%), followed by the use of electricity (16.74%) and transportation (11.8%). In addition, the environmental impact of sodium silicate to be put into the stage of the new bottle production was found to be 45.68%, causing severe influence on abiotic resource depletion and global warming.

• Resources Recycling
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• v.19 no.5
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• pp.13-24
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• 2010

To investigate the necessity and background of the metal recycling from urban mine resources, 4 bigger problems such as the limitation of the underground resources, consumption of the metal resources, contamination of environment and metal recycling business were reviewed. Waste management and recycling are the foremost issues facing Korea on its path to sustainable development in the 21st century. Especially, metal recycling from urban mines is the most urgent fact for global environment and resources conservation. In order to build a recycling-oriented society, it is necessary to develop the recycling technology, recycling practices and a recycling-oriented economic system.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.11
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• pp.589-595
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• 2016

This study evaluated the environmental impacts for landfill treatment of the wastewater treatment sludge (WTS) from petrochemical firms by life cycle assessment (LCA) and reviewed the impact reduction by landfill gas (LFG) utilization. The functional unit was 'landfill of 1 ton of WTS', and the system boundary included the process of input and treatment for WTS in landfill site. The impacts were high at landfill process (LP) and leachate treatment process (LTP). Global warming (GWP) and photochemical oxidants creation (POCP) were high at LP, while abiotic depletion (ADP), acidification (AP), eutrophication (EP), ozone depletion (ODP) were high at LTP. The major substances of various impact categories were crude oil (ADP), $NO_X$ (AP, EP), $CH_4$ (GWP, POCP), $Cl_2$ (ODP), respectively. The major factor of ADP, AP, EP was attributed from the generation of electricity used in LTP, and the methane within uncollected LFG was main factor of GWP and POCP. Therefore, electricity consumption reduction is identified to be an impact improvement option, and the flaring system installation or enhanced LFG recovery could be an alternative to reduce impacts. Among the various categories, GWP accounted the highest impact (${\geq}90%$) followed by ADP, POCP. In the avoidance impact resulted from the utilization of LFG, to substitute B-C oil or LNG showed the impact reduction of 32.7% and 12.0%, respectively.