• 제목/요약/키워드: Primary industry

검색결과 901건 처리시간 0.025초

다단제어용 안티 와인드업 기술 개발 (Development of Anti-windup Techniques for Cascade Control System)

  • 배정은;김경훈;추승철;허재필;임상훈;성수환
    • Korean Chemical Engineering Research
    • /
    • 제58권3호
    • /
    • pp.430-437
    • /
    • 2020
  • 본 연구에서는 다단제어(Cascade Control)를 위한 안티 와인드업(Anti-windup) 기술을 개발하였다. 다단제어는 외란을 보다 효과적으로 제어하기 위해 내부에 되먹임(Feedback) 제어루프를 추가한 제어구조이다. 단일루프제어(Single-loop Control)와는 다르게 두 개의 제어루프로 이루어져 내부의 종속제어루프(Secondary Control)가 외부의 주제어루프(Primary Control)에 영향을 미치는 특징을 가지고 있다. 산업현장에서 다단제어에 적용하는 기존의 안티 와인드업 기술은 주로 주제어기(Primary Controller)와 종속제어기(Secondary Controller)에 각각 로컬 역연산법(Back Calculation)을 적용하는 것이다. 하지만 이 방법은 종속제어기의 제어출력이 포화되었을 때 발생하는 주제어기의 적분누적(Integral-windup) 현상을 효과적으로 제거하지 못한다. 이를 해결하기 위해 기존 로컬 안티 와인드업 기술을 확대 적용한 두 가지의 다단제어용 안티 와인드업 기술을 제안한다. 첫 번째는 다단 조건부 적분법(Cascade Conditional Integration)이고 두 번째는 다단 역연산법(Cascade Back Calculation)으로 단일루프제어에 적용되어 왔던 로컬 조건부 적분법과 역연산법을 다단제어로 확대 적용하여 다단제어 시스템에서 PID제어기의 적분누적 현상을 방지하고자하였다. 개발한 다단 조건부 적분법과 다단 역연산법은 간단하고 직관적이면서도 종속제어기의 제어출력의 포화로 인해 발생한 적분누적현상을 효과적으로 방지할 수 있고 공정이나 제어기 형태에 상관없이 우수한 제어성능을 유지할 수 있었다. 향후 실제 공정 적용을 통해 신뢰성을 확보한다면 산업현장의 다단제어기 성능을 개선하는데 크게 기여를 할 수 있을 것이다.

Agricultural Machinery Manufacture in GHANA

  • Twum, A.
    • 한국농업기계학회:학술대회논문집
    • /
    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
    • /
    • pp.98-107
    • /
    • 1993
  • Domestic production of agricultural machinery has come to be seen as appropriate entry route in the capital goods industry for most African countries, including Ghana, which has purely and strongly agricultural -based economics with a weak industrial infrastructure. Recent studies in Ghana do indicate that in addition to possessing technological capability in the manufacture of handtools, there is evidence of increased production of machinery for the primary food processing sector. Local manufacture of tractors and associated implements is embryonic, with an average domestic production of agricultural machinery in Ghana and analyses the available technologies and economic indicators in the local agricultural machinery industry. Areas for indicators in the local agricultural machinery industry. Areas for future development are identified.

  • PDF

패션기업의 패션정보 활용 (Fashion Firm's Utilization of Fashion Information)

  • 정송향
    • 한국의류산업학회지
    • /
    • 제6권6호
    • /
    • pp.699-706
    • /
    • 2004
  • In today's fashion industry, directions for new products and high value added of fashion goods, product changes according to cycles, the shortening of life cycles, added value, planned obsolescence, and presentation is focused on fashion trends that will be selected by many consumers at the point of selling time. Therefore fashion information poses great importance and its weight is growing bigger everyday. Fashion information recognized to be important is reflected practically in the prediction of fashion changes in the fashion industry; especially, it is the first stage of the merchandising process that is the course of new product development. Presently, with some differences according to the size and specialized area of a firm, domestic fashion menufacturers obtain information from sales data of competing brands and their own, market information, consumer information based on primary data, shared fashion trend information given by domestic fashion information providing companies. Firms can not produce differentiated images and product concepts using such shared information. Although the types, importance and reflection of used information vary according to merchandising processes, all experts engaging in the merchandising of fashion products use the same shared information.

스마트농업 기술 및 표준화 동향 (Technology and Standardization Trends on Smart Agriculture)

  • 민재홍;박주영
    • 전자통신동향분석
    • /
    • 제33권2호
    • /
    • pp.77-85
    • /
    • 2018
  • At present, agriculture in Korea is experiencing difficulties, such as a stagnation in farm income, an increase in imported agricultural products, a decrease in arable land, a decrease in the self-sufficiency rate of grain, a decrease in rural population, and aging. To solve these problems and vitalize the rural economy, our government is promoting its 6th industrialization policy, which links agriculture with primary industry, secondary, industry and tertiary industry, and as well as smart agriculture based on information and communication technology. Smart agriculture is an agriculture form used to improve the quality of life in rural areas through making greater efficiency and intelligence by applying ICT convergence technology to the whole entire process of agricultural production, distribution, and consumption in the areas of outdoor agriculture, facility horticulture, and livestock. Therefore, in this paper, we analyze the policy, technology, and standardization trends of domestic and foreign smart agriculture, and suggest ways to apply them to domestic smart agriculture during the in the introduction stage.

건설 분야 M&A의 동향과 시사점 (Trend and Implications of Merger&Acquisitions of Construction Industry in Korea)

  • 김진호
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2013년도 추계 학술논문 발표대회
    • /
    • pp.206-207
    • /
    • 2013
  • In the recent years, the subject of the M&A of construction company has become one of important issue in the domestic construction industry. Therefore, the purpose of this research consider the rational plans of M&A not only for systematizing types about process of M&A in construction industry, but also for analyzing the significant characteristic of M&A in korea. To achieve this objective, this research performs a case study of M&A to embody the major trend and implications. The results of this research based on this methodology can be systematized as falling into two areas : 1)the primary types of M&A were divided into 4 categories by analyzing the results of interview, 2)the process of M& A from the result of case study.

  • PDF

국내 스마트양식 기술 동향 (Domestic Smart Aqua-farming Technology)

  • 정훈;허태욱;이일우
    • 전자통신동향분석
    • /
    • 제36권5호
    • /
    • pp.62-73
    • /
    • 2021
  • A stable protein source is required to support the rapidly increasing global population, and fishery products are a particularly important part of the required protein supply. However, due to continued overfishing, fishery resources are depleted, and the number of fish caught by fishing boats has stagnated. Consequently, the aquaculture industry is becoming increasingly important. Internationally, smart aquaculture technology that minimizes labor and environmental pollution has been established through technological developments supported by large investments in automation and water treatment technology over the last several decades. In the case of Korea, the aquaculture industry has not yet emerged as a labor-intensive primary industry. However, in recent years various attempts have been made to apply ICT technology to aquaculture to overcome these problems. In this study, domestic and foreign technologies and patent trends for smart aquaculture are analyzed. In addition, the current status of the smart aquaculture cluster business that the Ministry of Oceans and Fisheries has been promoting since 2019 to utilize ICT technology in aquaculture is introduced.

토공사를 위한 건설장비 투입 최적 조합 산정 시스템 개발 (Development of Determination System for Optimal Combination of Earthwork Equipments)

  • 박재우;염동준
    • 한국산업융합학회 논문집
    • /
    • 제23권6_2호
    • /
    • pp.957-969
    • /
    • 2020
  • The primary objective of this study is to develop a determination system for an optimal combination of earthwork equipment that improves the traditional way in convenience, prediction accuracy, and productivity. For this, the following research works are conducted sequentially; 1)literature review, 2)technology development trend analysis, 3)develop a determination system for the optimal combination of earthwork equipment, 4)simulation of a developed system. As a result, core considerations are deducted for the development of a determination system. Furthermore, site simulation is performed using a developed system. Site simulation result, Cluster 1(R1200LC 7㎥, CAT 775G 65ton×2) was selected from 6 clusters because of its production cost (₩491/㎥). It is expected that the application range and impact on the construction industry will be enormous due to the availability of the developed system.

산업관련표(産業關聯表)에 의(依)한 임업구조분석(林業構造分析)과 유발생산액(誘發生産額) -임업(林業)이 한국경제(韓國經濟)에 미치는 영향(影響)- (Analysis of Forestry Structure and Induced Output Based on Input - output Table - Influences of Forestry Production on Korean Economy -)

  • 이승윤
    • Journal of the Korean Wood Science and Technology
    • /
    • 제2권4호
    • /
    • pp.4-14
    • /
    • 1974
  • The total forest land area in Korea accounts for some 67 percent of the nation's land total. Its productivity, however, is very low. Consequently, forest production accounts for only about 2 percent of the gross national product and a minor proportion of no more than about 5 percent versus primary industry. In this case, however, only the direct income from forestry is taken into account, making no reference to the forestry output induced by other industrial sectors. The value added Or the induced forestry output in manufacturing the primary wood products into higher quality products, makes a larger contribution to the economy than direct contribution. So, this author has tried to analyze the structure of forestry and compute the repercussion effect and the induced output of primary forest products when utilized by other industries for their raw materials, Hsing the input-output table and attached tables for 1963 and 1966 issued by the Bank of Korea. 1. Analysis of forestry structure A. Changes in total output Durng the nine-year period, 1961-1969, the real gross national product in Korea increased 2.1 times, while that of primary industries went up about 1. 4 times. Forestry which was valued at 9,380 million won in 1961, was picked up about 2. 1 times to 20, 120 million won in 1969. The rate of the forestry income in the GNP, accordingly, was no more than 1.5 percent both in 1961 and 1962, whereas its rate in primary industries increased 3.5 to 5.4 percent. Such increase in forestry income is attributable to increased forest production and rise in timber prices. The rate of forestry income, nonetheless, was on the decrease on a gradual basis. B. Changes in input coefficient The input coefficient which indicates the inputs of the forest products into other sectors were up in general in 1966 over 1963. It is noted that the input coefficient indicating the amount of forest products supplied to such industries closely related with forestry as lumber and plywood, and wood products and furniture, showed a downward trend for the period 1963-1966. On the other hand, the forest input into other sectors was generally on the increase. Meanwhile, the input coefficient representing the yolume of the forest products supplied to the forestry sector itself showed an upward tendency, which meant more and more decrease in input from other sectors. Generally speaking, in direct proportion to the higher input coefficient in any industrial sector, the reinput coefficient which denotes the use of its products by the same sector becomes higher and higher. C. Changes in ratio of intermediate input The intermediate input ratio showing the dependency on raw materials went up to 15.43 percent m 1966 from 11. 37 percent in 1963. The dependency of forestry on raw materials was no more than 15.43 percent, accounting for a high 83.57 percent of value added. If the intermediate input ratio increases in any given sector, the input coefficient which represents the fe-use of its products by the same sector becomes large. D. Changes in the ratio of intermediate demand The ratio of the intermediate demand represents the characteristics of the intermediary production in each industry, the intermediate demand ratio in forestry which accunted for 69.7 percent in 1963 went up to 75.2 percent in 1966. In other words, forestry is a remarkable industry in that there is characteristics of the intermediary production. E. Changes in import coefficient The import coefficient which denotes the relation between the production activities and imports, recorded at 4.4 percent in 1963, decreased to 2.4 percent in 1966. The ratio of import to total output is not so high. F. Changes in market composition of imported goods One of the major imported goods in the forestry sector is lumber. The import value increased by 60 percent to 667 million won in 1966 from 407 million won in 1963. The sales of imported forest products to two major outlets-lumber and plywood, and wood products and furniture-increased to 343 million won and 31 million won in 1966 from 240million won and 30 million won in 1963 respectively. On the other hand, imported goods valued at 66 million won were sold to the paper products sector in 1963; however, no supply to this sector was recorded in 1963. Besides these major markets, primary industries such as the fishery, coal and agriculture sectors purchase materials from forestry. 2. Analysis of repercussion effect on production The repercussion effect of final demand in any given sector upon the expansion of the production of other sectors was analyzed, using the inverse matrix coefficient tables attached to the the I.O. Table. A. Changes in intra-sector transaction value of inverse matrix coefficient. The intra-sector transaction value of an inverse matrix coefficient represents the extent of an induced increase in the production of self-support products of the same sector, when it is generated directly and indirectly by one unit of final demand in any given sector. The intra-sector transaction value of the forestry sector rose from 1.04 in 1963 to 1, 11 in 1966. It may well be said, therefore, that forestry induces much more self-supporting products in the production of one unit of final demand for forest products. B. Changes in column total of inverse matrix coefficient It should be noted that the column total indicates the degree of effect of the output of the corresponding and related sectors generated by one unit of final demand in each sector. No changes in the column total of the forestry sector were recorded between the 1963 and 1966 figures, both being the same 1. 19. C. Changes in difference between column total and intra-sector transaction amount. The difference between the column total and intra-sector transaction amount by sector reveals the extent of effect of output of related industrial sector induced indirectly by one unit of final demand in corresponding sector. This change in forestry dropped remarkable to 0.08 in 1966 from 0.15 in 1963. Accordingly, the effect of inducement of indirect output of other forestry-related sectors has decreased; this is a really natural phenomenon, as compared with an increasing input coefficient generated by the re-use of forest products by the forestry sector. 3. Induced output of forestry A. Forest products, wood in particular, are supplied to other industries as their raw materials, increasng their value added. In this connection the primary dependency rate on forestry for 1963 and 1966 was compared, i. e., an increase or decrease in each sector, from 7.71 percent in 1963 to 11.91 percent in 1966 in agriculture, 10.32 to 6.11 in fishery, 16.24 to 19.90 in mining, 0.76 to 0.70 in the manufacturing sector and 2.79 to 4.77 percent in the construction sector. Generally speaking, on the average the dependency on forestry during the period 1963-1966 increased from 5.92 percent to 8.03 percent. Accordingly, it may easily be known that the primary forestry output induced by primary and secondary industries increased from 16, 109 million won in 1963 to 48, 842 million won in 1966. B. The forest products are supplied to other industries as their raw materials. The products are processed further into higher quality products. thus indirectly increasing the value of the forest products. The ratio of the increased value added or the secondary dependency on forestry for 1963 and 1966 showed an increase or decrease, from 5.98 percent to 7.87 percent in agriculture, 9.06 to 5.74 in fishery, 13.56 to 15.81 in mining, 0.68 to 0.61 in the manufacturing sector and 2.71 to 4.54 in the construction sector. The average ratio in this connection increased from 4.69 percent to 5.60 percent. In the meantime, the secondary forestry output induced by primary and secondary industries rose from 12,779 million Wall in 1963 to 34,084 million won in 1966. C. The dependency of tertiary industries on forestry showed very minor ratios of 0.46 percent and 0.04 percent in 1963 and 1966 respectively. The forestry output induced by tertiary industry also decreased from 685 million won to 123 million won during the same period. D. Generally speaking, the ratio of dependency on forestry increased from 17.68 percent in 1963 to 24.28 percent in 1966 in primary industries, from 4.69 percent to 5.70 percent in secondary industries, while, as mentioned above, the ratio in the case of tertiary industry decreased from 0.46 to 0.04 percent during the period 1963-66. The mining industry reveals the heaviest rate of dependency on forestry with 29.80 percent in 1963 and 35.71 percent in 1966. As it result, the direct forestry income, valued at 8,172 million won in 1963, shot up to 22,724 million won in 1966. Its composition ratio lo the national income rose from 1.9 percent in 1963 to 2.3 per cent in 1966. If the induced outcome is taken into account, the total forestry production which was estimated at 37,744 million won in 1963 picked up to 105,773 million won in 1966, about 4.5 times its direct income. It is further noted that the ratio of the gross forestry product to the gross national product. rose significantly from 8.8 percent in 1963 to 10.7 percent in 1966. E. In computing the above mentioned ratio not taken into consideration were such intangible, indirect effects as the drought and flood prevention, check of soil run-off, watershed and land conservation, improvement of the people's recreational and emotional living, and maintenance and increase in the national health and sanitation. F. In conclusion, I would like to emphasize that the forestry sector exercices an important effect upon the national economy and that the effect of induced forestry output is greater than its direct income.

  • PDF

포도 품종별 메탄올 추출물로부터 면역활성 분석 (Analysis of Immunomodulating Activities in Methanol Extracts from Several Kinds of Grapes)

  • 허진철;우상욱;권미애;김보배;이숙희;이진만;최종욱;정신교;이상한
    • 한국식품저장유통학회지
    • /
    • 제14권4호
    • /
    • pp.419-424
    • /
    • 2007
  • 하우스 포도 중 대표적인 것으로는 거봉, 델라웨어, 캠벨, 청포도를 열거할 수 있는데, 이에 대한 생물학적 활성 효과 중 항산화와 항암 활성에 대한 보고는 많으나 면역활성에 대한 활성의 연구는 미흡한 실정이다. 이에 우리는 4종의 포도의 메탄올 추출물로 항산화, 항암, 그리고 면역활성을 분석하였다. 전자공유능을 측정하기 위한 DPPH를 이용한 실험 결과 포도 4종에서 모두 항산화 활성을 나타내었으며, 환원력을 알아보기 위한 FRAP 실험 또한 활성을 나타내었다. 산화스트레스에 의한 세포사멸 억제 효과는 약간 있는 것으로 나타났다. 반면에 포도 추출물에 의한 cell proliferation 활성은 증가하는 것으로 나타났다. Nitric oxide (NO) 생성 억제 실험에서는 LPS에 의해 유도된 NO의 활성을 감소시키지는 않으나 포도 추출물 자제가 Raw 264.7 세포에서 NO의 활성을 유도하는 것으로 나타났다. Wound healing assay를 이용하여 항암효과를 알아본 결과 포도추출물 4종에서 세포의 운동성을 억제하는 효과를 가지는 것으로 나타났다. Mouse primary spleen cell 에서의 cytokine IL-4, IL-13의 활성을 알아본 결과 Con A로 유도된 IL-4와 IL-13의 발현 양을 현저히 줄이는 것으로 나타났다. 이로 미루어 보아, 포도 4종에 대한 생물학적 활성 결과 항산화, 항암활성은 물론 항천식 활성이 있는 것으로 확인되어 면역조절 활성이 포도의 기능성에 중요한 역할을 할 것으로 판단된다.

Cooperative Power Control Scheme for a Spectrum Sharing System

  • Ban, Tae-Won;Jung, Bang-Chul
    • Journal of information and communication convergence engineering
    • /
    • 제9권6호
    • /
    • pp.641-646
    • /
    • 2011
  • In this paper, we investigate a power control problem which is very critical in underlay-based spectrum sharing systems. Although an underlay-based spectrum sharing system is more efficient compared to an overlay-based spectrum sharing system in terms of spectral utilization, some practical problems obstruct its commercialization. One of them is a real-time-based power adaptation of secondary transmitters. In the underlay-based spectrum sharing system, it is essential to adapt secondary user's transmit power to interference channel states to secure primary users' communication. Thus, we propose a practical power control scheme for secondary transmitters. The feedback overhead of our proposed scheme is insignificant because it requires one-bit signaling, while the optimal power control scheme requires the perfect information of channel states. In addition, the proposed scheme is robust to feedback delay. We compare the performance of the optimal and proposed schemes in terms of primary user's outage probability and secondary user's throughput. Our simulation results show that the proposed scheme is almost optimal in terms of both primary user's outage probability and secondary user's throughput when the secondary user's transmit power is low. As the secondary user's transmit power increases, the primary user's outage probability of the proposed scheme is degraded compared with the optimal scheme while the secondary user's throughput still approaches that of the optimal scheme. If the feedback delay is considered, however, the proposed scheme approaches the optimal scheme in terms of both the primary user's outage probability and secondary user's throughput regardless of the secondary user's transmit power.