• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.2
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• pp.101-108
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• 2012

To determine sulfate uptake and assimilation of various rape cultivars (Brassica napus L.) under different S levels, the activity of ATP sulfurylase, ${SO_4}^{2-}$ uptake and glutathione (GSH) concentrations were measured in different age of leaves. In this study, ten rape cultivars (Mokpo, Tamra, Youngsan, Naehan, Saturnin, Akela, Mosa, Capitol, Pollen, and Colosse) showed various sulfate uptake and assimilation capacity in response to inefficient sulfate supply. Under inadequate sulfate conditions, a greater ATP sulfurylase activity in young leaves was observed in all cultivars compared to that of old leaves. In addition, GSH concentration was considerably increased in young leaves when S supply was declined from 2.0 to 0.2 mM. These results suggested that rape cultivars differ in their capacity to utilize sulfate under limited S conditions.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.11
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• pp.2671-2676
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• 2015

Nowadays, Mobile devices are now capable of supporting a wide range of applications. Unfortunately, some of applications demand an ever increasing computational power and mobile devices have limited resources due to their constraints, such as low processing power, limited memory, unpredictable connectivity, and limited battery life. To deal with mobile devices' constraints, researchers envision extending cloud computing services to mobile devices using virtualization techniques to shift the workload from mobile devices to a powerful computational infrastructure. Those techniques consist of migrating resource-intensive computations from a mobile device to the resource-rich cloud, or server (called nearby infrastructure). In this paper, we want to highlight on cloudlet architecture (nearby infrastructure with mobile devices), its functioning and in our future work, analyze effects of distance between cloudlet and mobile devices.

• Journal of Life Science
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• v.7 no.2
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• pp.107-111
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• 1997

To remove dissolved $NH_{4}$$^{+}$ in the aquaculture system, one ammonia oxidizing bacterium, Nitrsomonas sp. PK1, was isolated from samples collected in many aquacultural place and sludges of waste water. The stationary phase of this atrain was reached after 9 days, and the maximum $NO_{2}$ production was shown from 3 days to 9 days. In the selective medium, 0.1% of glucose was the good carbon source for growth. However, the $NO_{2}$productivity was repressed by the addition of glucose to the medium. When $Zn^{++}$ ion was supplemented to the medium, growth and the $NO_{2}$ productivity was increased, 10mM of $ZnCl_{2}$ was the optimal concentration for growth and 1 mM of $ZnCl_{2}$ was the optimal concentration for the production of $NO_{2}$, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.306-313
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• 2019

Owing to the present problems of air pollution and fossil fuel exhaustion, ongoing research has been actively focused on developing an electric actuator system that can utilize diverse energy sources without producing any exhaust gas. Since the motors of such electric vehicles generally rotate at a high speed, the initial acceleration capability required for an automobile is insufficient. In this study, the motor output was decelerated by the transmission; the initial acceleration of the vehicle was increased, and the motor size and weight were reduced. The driving motor and transmission, which each form isolated structures, were integrated to simplify the connector for input and output. By reducing the cooling system's capacity, a vehicle was designed and manufactured that represents a structural change in effective technology.

• Journal of the Economic Geographical Society of Korea
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• v.24 no.2
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• pp.163-180
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• 2021

Nuclear power has been an attractive energy efficient and to the pressure with the climate change despite of its risks. There are safety, security, and environmental concerns with the nuclear radiation, but the techno-optimism forms the mainstream by experts and the state to be able to control and manage the risks yet occurred. The disastrous Chernobyl and Fukushima nuclear accidents brought about alternative action and thought including renewable energy expansion, efficient energy delivery and use, and enhancing stewardship to environmental carrying capacity. More significant alternative movement is sought by victims of nuclear radiation, technicians, and the general public who realized the pitfalls of expert and state centered policy formation. These laypersons become counter-expertise competent in recognizing local contamination and considering the risks and emotions seriously affecting peoples' everyday lives. They play important roles in the construction and legitimation of alternative knowledge about nuclear power widely realized across regions.

• Journal of Science and Technology Studies
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• v.18 no.2
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• pp.95-133
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• 2018

Since the beginning of the millennium, 'Maker Movement' has been active throughout the world. Today, there is a maker fair every year in major cities of the world including Seoul, and the number of attendees is increasing day by day, so it can be seen as a kind of maker 'phenomenon'. The positive implication of the maker's movement is that it attempts to break down the monopoly of manufacturing and to restore the rights and capabilities of citizens as makers. Today, highly developed industrial capitalism has a tendency to structurally paralyse citizens, to tie their hands and feet, and to degenerate into consuming entities only. Therefore, it can be said that the maker movement has structural tensions in the relationship of neoliberal manufacturing culture. This study is an attempt to actively interpret the maker movement in terms of "critical making". The maker movement can trace its origins to "counterculture" and "new communalism" that emerged in the United States in the 1960s and 1970s. On the other hand, there is criticism that the maker movement can fall into another technology utopianism and function as an area of consumer society, and mobilize it in the direction of activating consumerism. Although the maker's movement is amorphous due to its characteristics and it is currently in progress, it is difficult to make crude definition yet. However, as the citizens who have been defined only as consumers of science and technology, are newly emerging as producers of makers, there have been great changes in the topography of science and technology and civil society. So the scientific implication of the maker movement is great in that it shows the possibility of causing it.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.1
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• pp.34-48
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• 1982

1. Production and consumption of chemical fertilizers in Korea could be divided into five different phases of total imports, setting up fertilizer plants, self-sufficiency in production, net export, and diversification in compound fertilizers. Currently the nation has production capacity of 800 thousand M/T of nitrogen, 400 thousand M/T of phosphate ($P_2O_5$) and 200 thousand M/T of potash ($K_2O$). 2. Yearly consumption increased every year, since 1964, 28,000 M/T N, 7,700 M/T $P_2O_5$, and 7,500 M/T $K_2O$ until 1972, when the increase jumped by eight times for $P_2O_5$ and seven times for $K_2O$ for the following 3 years in anticipation of their short supply. Now total consumption has been more or less stabilized at the level of 450 thousand M/T N, 220 thousand M/T $P_2O_5$ and 180 thousand M/T $K_2O$ for the last 7 years. 3. Current operation rate of fertilizer plants is around 80% throughout the whole industry, after going through several different levels depending on demand at times. 4. Fertilizer export started in 1967 and reached a peak of 150 thousand nutrient ton in 1972, about 20% of total production, before temporarily stopping due to over-demand for next three years. The export resumed again in 1976 rise to the all time high of 670 thousand nutrient ton in 1980, almost half of total production, and then started to decline due to higher price of petroleum since then. 5. The decline in fertilizer export appears to be accelerated because several countries, in South-Eastern Asia, traditional export market for Korean fertilizers, started to build their own plants, since 1980, based on their raw materials of especially petroleum. 6. Current consumption in Korea is about 30 nutrient Kg per 10a, equivalent to that in Western European countries, partly due to new high-yielding rice varieties and extensive cultivation of fruit trees and vegetables. Additional fertilizer demand in future can be anticipated in reclaimed land for growing grass and forestry.

• Korean Journal of Poultry Science
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• v.16 no.2
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• pp.105-127
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• 1989

Although poultry industry in Japan has been much developed in recent years, it still needs to be developed , compared with developed countries. Since the poultry market in Korea is expected to be opened in the near future it is necessary to maximize the Productivity to reduce the production costs and to develop the scientific, technologies and management organization systems for the improvement of the quality in poultry production. Followings ale the summary of poultry industry in Japan. 1. Poultry industry in Japan is almost specized and commercialized and its management system is ： integrated, cooperative and developed to industrialized intensive style. Therefore, they have competitive power in the international poultry markets. 2. Average egg weight is 48-50g per day (Max. 54g) and feed requirement is 2. 1-2. 3. 3. The management organization system is specialized and farmers in small scale form complex and farmers in large scale are integrated.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.05a
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• pp.1023-1026
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• 2006

에드 혹 네트워크는 불규칙한 이동성을 지닌 다수의 노드들에 의해 자율적으로 구성되는 네트워크이다. 그러나 에드 혹 네트워크는 저 전력, 낮은 프로세싱 능력, 무선채널이라는 에드 혹 네트워크만의 특징으로 인해 패킷 드롭, 재전송 공격, 서비스 거부 공격, 비잔틴 공격, 신원사칭과 같은 보안상 여러 가지 공격에 취약하다는 문제점을 안고 있다. 때문에 이러한 취약점을 개선하려는 방안으로 노드 간에 인증, 기밀성, 무결성을 비롯한 여러 가지 요소를 충족시키기 위한 보안기법이 연구되어 왔다, 그러나 Ad Hoc 네트워크는 기존의 회선을 사용하는 정적인 형태의 네트워크가 아닌 시간에 동적으로 네트워크 구조가 변화하며, 네트워크에서 불규칙한 이동성을 지닌 노드들은 적은양의 자원을 소유하는 원인으로 인해 기존의 보안기법은 효과적이지 못하다. 본 논문에서는 신뢰성이 확보된 이웃 노드 간에 그룹을 형성하고, 그룹멤버의 안전성을 입증하는 그룹 인증서를 생성하여 그룹에 접근하는 단일노드 혹은 또 다른 그룹간의 인증을 수행하는 기법을 제안한다. 또한 그룹 멤버 간에 그룹 키를 생성하여 데이터 유출에 대한 위험성 문제를 해결하고, 인증과 기밀성 유지로 인한 자원소비를 감소시킬 수 있도록 하였다.

• Corrugated packaging logistics
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• s.63
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• pp.87-90
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• 2005

1856년 7월 7일 영국에서 에드워드 찰스 힐리와 에드워드 엘리스 알렌 (Edward Charles Healey & Edward Ellis Allen)에 의해 골판지가 처음 발명되었고, 15년후인 1871년 12월 19일에 현재의 골판지상자 형태의 특허가 미국의 알버트 L. 존스(Albert. L. Jones)에게 취득 된지 130여년이상이 지난 이 시대에는 실로 다양한 분야에서 골판지를 사용하고 있지만, 주 사용분야는 포장산업의 분야이다. 과거에는 포장의 주목적은 첫째 포장 내용물(상품)의 보호 둘째 상품의 운송과 적재 및 취급의 편리성 셋째 상품 구매동기 유발의 순서이었으나 최근에는 첫째와 둘째의 목적은 필수불가결한 것이고 세번째의 상품 구매동기 유발의 목적에 더 큰 비중이 있는 추세이다. 따라서 포장재의 규격은 생산자의 입장에서는 보다 단순해지고 규격화 되는 것이 생산코스트의 절감과 생산성 향상의 지름길이지만 (그러나 더욱 복잡해지고 비규격화 되는 것이 제품 부가가치가 더 높을 수도 있기 때문에 여기에는 보다 신중한 판단이 필요하다)각종 통신기술, 인터넷과 I.T산업의 발달과 더불어 소비자가 언제라도 상품의 다양한 정보에 쉽게 접할 수 있는 이시대에는, 다양한 소비계층의 NEED를모두 만족시켜 줄려고 하는 상품 개발자의 제품설계 및 개발과 판매전략에 의해 더욱 더 상품은 다양해지고 이에 따라서 포장재의 형태도 더욱 다양해지고 복잡해지고 있다. (필자의 판단으로는 앞으로 보다 더 다양해지고 복잡해지고 있는 추세이다.) 즉 다시 말하면 이러한 다양한 형태의 포장재의 변화를 수용하여, 가장 높은 가격 경쟁력으로, 적시에 가장 빠르게 생산하며 공급할 수 있는 능력을 갖춘 포장재 제조업자 만이 미래에는 적자생존 할 수 있다는 결론이다.