• Title/Summary/Keyword: Shift pattern

Search Result 431, Processing Time 0.03 seconds

Thermocontrol of Solute Permeation across Polymer Memberane Composed of Poly(N, N-dimethylaminoethyl methacrylate) and Its Copolymers

  • Yuk, Soon-Hon;Cho, Sun-Hang
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.6 no.4
    • /
    • pp.274-278
    • /
    • 2001
  • Polymer membranes composed of N, N-dimethylaminoethyl methaccrylate(DMAEMA) and acrylamide(AAm)(or ethyl acrylamide(EAAm) were prepared to demonstrated the thermo-control of solute permeation. Poly DMEMA has a lower critical solution temperature(LCST) at around 50$\^{C}$ in water, With the copolymerization of DMAEMA with AAm (or EAAm) a shift in the LCST to a lowere temperature was observed, probably due to the formation of hydrogen bonds between the amide and N-N-dimethylamino groups. However, the temperature-induced phase transition of poly(DMAEMA-co-EAAm) did not show a similar trend to that of poly(DMAEMA- co-AAm) in the gel state. The hydrogen bonds in poly(DMAEMA-co-EAAm) were significantly disrupted with the formation a gel network, which led to a difference in the swilling behavior of polymer gels in response to temperature. To apply these polymers to temperature-sensitive sol-ute permeation, polymer membranes were prepared. The permeation pattern of hydrocortisone, used as the model solute, was explained based on the temperature-sensitive swelling behavior of the polymer membranes.

  • PDF

A Study on Cutting Force Measurement Using a Cylindrical Capacitive Spindle Sensor (주축 변위 센서를 이용한 절삭력 측정에 관한 연구)

  • 김일해;장동영;한동철
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.11 no.2
    • /
    • pp.17-23
    • /
    • 2002
  • A cylindrical capacitance-type spindle displacement sensor was developed and its effectiveness as a system to monitor cutting forces during hard turning was tested in this research. The sensor was installed between the face of spindle cover and the chucking element and measured pure radial motion of the spindle under the condition with presence of roundness error at measured surface. To prove the effectiveness of the developed system hard aiming tests using ceramic inserts and tool steel as workpiece were conducted. The workpiece was hardened up to 65 Rc. The variations of pure radial motion of the spindle ware measured during the cutting tests. The signals from the sensor showed the same pattern of cutting force variations from the tool dynamometer due to the progress of tool wear. As the flank wear of the ceramic tool increased both static component of cutting forces and the amount of center shift of spindle orbit increased, Results from the research showed that the developed sensor could be utilized as an effective and cheap on-line sensing device to monitor cutting conditions and tool performance in the un-manned machining center.

Cadmium Detoxification Mechanism in Klebsiella aerogenes ATCC 10031 (Klebsiella aerogenes ATCC 10031의 카드뮴 해독기작)

  • 이기성;유순애;곽인영;박영식;최영길
    • Korean Journal of Microbiology
    • /
    • v.28 no.2
    • /
    • pp.134-144
    • /
    • 1990
  • In order to examine that what kind of system correlated with cadmium detoxification mechanism in Klebsiella aerogenes ATCC 10031, we tried to investigate the effect of phosphate upon the detoxification and also elucidate whether the cadmium phosphate and/or polymeric Cd-Pi complex is formed actually in cell or not. As the results, it was shown that growing pattern had long lag adaptive phase of 12 hr to 24 hr, at the concentrations of 0.02 mM and 0.08 mM cadmium, respectively. Cadmium was accumulated more highly in the fraction of cell wall and membrane than in those of cytoplasm. In case of phosphate starving cells added cadmium, inorganic polyphosphate system was primarily correlated with Cd-detoxification during the lag phase for the accommodation to cadmium, on the other hand, Cd:Sulfide complex system secondarily correlated it during the stationary phase. These results implied that polyphosphate system and Cd:sulfide complex system, these two systems were operated compensatively each other. Considering the results obsdrved with EM and examined tha changes of sulfide and polyphosphate amount, it was reflected that Cd:S complex was located at the cell surface. In the results of $in-vivo^{31}$P NMR spectra in the cells with cadmium pressure, several phosphate signals arose newly from the polyphosphate region with moving chemical shift of it. This phinomenon strongly implied the actual existence of Dd:Pi comples and /or Cd:poly-P complex in the cell and also the cellular compartmentalization of cadmium detoxifying mechanism.

  • PDF

Consideration on new research direction in marine environmental sciences in relation to climate change (기후변화에 대비한 환경연구의 방향)

  • Kim, Su-Am
    • Journal of Environmental Policy
    • /
    • v.1 no.1
    • /
    • pp.1-24
    • /
    • 2002
  • Due to the recent increase in greenhouse gases in atmosphere, world climate is rapidly changing and in turn, the earth ecosystem responds upon the climate changes. Comparing the ecosystem in the past, the present shapes of ecosystem is the result of the serious modification. Fishery resources in marine ecosystem, which usually occupy the upper trophic level, are also inevitable from such changes, because they always react to the natural environmental conditions. The northwestern Pacific is the most productive ocean in the world producing about 30% of world catch. From time to time, however, it has been notified that abundance, distribution and species composition of major fish species were altered by climate events. Furthermore, primary productivity of the ocean is not stable under the changing environments, so that carrying capacity of the ocean varies from one climate regime to another. Major climate events such as global warming, atmospheric circulation pattern, climate regime shift in the North Pacific, and El Nino event in the Pacific tropical waters were introduced in relation to fisheries aspects. The current status and future projection of fishery production was investigated, especially in the North Pacific including Korean waters. This new paradigm, ecosystem response to environmental variability, has become the main theme in marine ecology and fishery science, and the GLOBEC-type researches might provide a solution far cause-effect mechanism as well as prediction capability. Ecosystem management principles for multi-species should be adopted for better understanding and management of ecosystem.

  • PDF

Pycnogenol attenuates the symptoms of immune dysfunction through restoring a cellular antioxidant status in low micronutrient-induced immune deficient mice

  • Lee, Jeongmin;Nam, Da-Eun;Kim, Ok-Kyung;Lee, Myung-Yul
    • Nutrition Research and Practice
    • /
    • v.8 no.5
    • /
    • pp.533-538
    • /
    • 2014
  • BACKGROUND/OBJECTIVES: We investigated the effect of Pycnogenol (Pyc) on survival and immune dysfunction of C57BL/6 mice induced by low micronutrient supplementation. MATERIALS/METHODS: Female C57/BL/6 mice were fed a diet containing 7.5% of the recommended amount of micronutrients for a period of 12 wks (immunological assay) and 18 wks (survival test). For immunological assay, lymphocyte proliferation, cytokine regulation, and hepatic oxidative status were determined. RESLUTS: Pyc supplementation with 50 and $100mg{\cdot}kg^{-1}{\cdot}bw{\cdot}d^{-1}$ resulted in partial extension of the median survival time. Pyc supplementation led to increased T and B cell response against mitogens and recovery of an abnormal shift of cytokine pattern designated by the decreased secretion of Th1 cytokine and increased secretion of Th2 cytokine. Hepatic vitamin E level was significantly decreased by micronutrient deficiency, in accordance with increased hepatic lipid peroxidation level. However, Pyc supplementation resulted in a dose-dependent reduction of hepatic lipid peroxidation, which may result from restoration of hepatic vitamin E level. CONCLUSION: Findings of this study suggest that Pyc supplementation ameliorates premature death by restoring immune dysfunction, such as increasing lymphocyte proliferation and regulation of cytokine release from helper T cells, which may result from the antioxidative ability of Pyc.

The Shift to the Service Economy and the Characteristic of the Structural Change since Financial Crisis in Korea -Focused on the Analysis of Manufacturing and Service Industry using Productivity Decomposition Methodology and International Comparison- (외환위기 이후 한국경제의 서비스화와 구조변화의 특징 - 생산성 분해를 통한 제조업과 서비스업 업종별 분석과 국제비교를 중심으로 -)

  • Ban, Ga Woon
    • Journal of Labour Economics
    • /
    • v.33 no.1
    • /
    • pp.85-107
    • /
    • 2010
  • In this article, since the financial crisis, Korean employment movement to service market, productivity gap between manufacturing and service industry was significant compared with other countries. The results from productivity decomposition show that negative structural changes, which employment increase is contrary to the productivity, have been intensified since the financial crisis. It is caused from a different developing pattern. While the proportion of employment was reduced, productivity has improved in manufacturing industry. While the developing was due to the high increase of the employment proportion in service industry, productivity was not improved significantly. This tendency is clearly revealed in international comparisons. In Korea the negative trend of structural changes in service industry are intensified compared to manufacturing industry after the financial crisis.

  • PDF

Parellel Computation of the Shift Table of a Hashing-Based Algorithm for the Order-Preserving Multiple Pattern Matching (순위다중패턴매칭을 위한 해싱기반 알고리즘의 이동테이블 병렬계산)

  • Park, Jeonghoon;Kim, Youngho;Kwan, Sanghoon;Sim, Jeong Seop
    • Annual Conference of KIPS
    • /
    • 2017.04a
    • /
    • pp.36-39
    • /
    • 2017
  • 길이가 같은 두 문자열의 같은 위치에 있는 문자의 순위가 모두 일치할 때, 두 문자열은 순위동형이라 한다. 순위다중패턴매칭문제는 텍스트 T와 k개의 패턴들의 집합 $P^{\prime}=\{P_1,P_2{\ldots},P_k\}$이 주어졌을 때, P'의 패턴들과 순위동형인 T의 모든 부분문자열의 위치를 찾는 문제이다. 최근 전처리단계에서 P'에 대한 이동테이블을 O(kmqlogq) 시간에 계산하여 순위다중패턴매칭문제를 해결하는 해싱기반 알고리즘이 제시되었다. 이때 P'에서 가장 짧은 패턴의 길이를 m, q-그램의 길이를 q라고 한다. 본 논문에서는 P'이 주어졌을 때, 이동테이블을 O(mqlogq) 시간에 계산하는 병렬알고리즘을 제시한다. 실험결과, 본 논문에서 제시하는 병렬알고리즘은 k개의 스레드를 이용하여 m=100, q=5에 대해 k=100일때와 k=1,000일 때 순차알고리즘보다 각각 약 12.9배, 약 215배 빠른 수행시간을 보였다.

A Study on the Commercial Franchising in China - Focus on the Baojing Case - (중국의 프랜차이즈계약에 관한 연구 - 보경사건을 중심으로 -)

  • SONG, Soo-Ryun
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.67
    • /
    • pp.49-68
    • /
    • 2015
  • In recent years in China, corresponding to a shift in consumption pattern from household basics to greater expenditure on quality of life, new franchising opportunities arise. Although the franchising prospect in China is promising, Korean companies aiming at franchising into China need to be aware of the legal framework for commercial franchise in China as this will have direct impact on their business expansion. Where franchising activities involve trade mark licence, Chinese Franchise Regulations require such trade mark licence agreement to be regulated in accordance with the relevant provisions of the Chinese Trademark Law. Furthermore where one party fails to perform his obligation and it impacts purpose of the contract seriously, the other party could avoid the contract in accordance with the relevant provisions of the Chinese Contract Law. To launch franchising business successfully in China, Korean companies do market research sufficiently before they may commence franchise business. Korean franchisor must register with local authorities in China by own name, and make Chinese partner take charge of management of the distribution network and invitation of franchisee partners.

  • PDF

정보학분야 연구동향 분석

  • 서은경
    • Journal of the Korean Society for information Management
    • /
    • v.14 no.1
    • /
    • pp.269-291
    • /
    • 1997
  • The study examines research themes, the relationship with other disciplines, and disciplinary organization of Information Science n order to analyze general research patterns in the field of Information Science. The methods used for this study is subject analysis of the journal articles and citation analysis. In result, it is found that most researchers in Information Science have studied on 'library-related information science'. But the study also finds the research pattern shift from library-related study to computer-related study.

  • PDF

Studies on the Mackerel Purse Seine Operating in the Sea Area of Cheju Island - 2 . Model Experiment ob the Deformation of Net in Two Layer Current (제주도 주변 해역 고등어 포착망의 연구 - 2 . 이중조에 있어서 망의 변형에 관한 모형실험 -)

  • 박정식
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.22 no.4
    • /
    • pp.32-40
    • /
    • 1986
  • A model experiment of purse seine by the circulating water tank was carried out on the changes of net shape and the tension of purseline under operation in two layer current. In the circular tank, the two layer current was made by cutting off the current of upper layer and producing the bottom current by the equipment shown in Fig. 1. The model experiment of purse sein was made on a reduced scale 1 :400, and the experiment was carried out according to the Tauti's model law. When the bottom current of O. 5 knot flows to lower part of three-eighths of net, following results are derived. The depth of sinkerline reached only about 80% of that of no current set. The horizontal shift of sinker line caused by the bottom current is maximized in tight set. The enclosed area by the floatIine immediately after the completion of set net is 61. 5% in tight set, 50. 0 % in loose set and 54. 1 % in lateral set of those in the case of no current. In the first half period of pursing, the tension of the purseline is enhenced by the bottom current and the pattern of increasing is irregular in the tension curves.

  • PDF