• Title/Summary/Keyword: declining method

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Pacific Sea Level Variability associated with Climate Variability from Altimetry and Sea Level Reconstruction Data (위성 고도계와 해수면 재구성 자료를 이용한 기후변동성에 따른 태평양 해수면 변화)

  • Cha, Sang-Chul;Moon, Jae-Hong
    • Ocean and Polar Research
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    • v.40 no.1
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    • pp.1-13
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    • 2018
  • Previous studies have indicated a great regional difference in Sea Level Rise (SLR) in the Pacific and it has been suggested that this is linked to climate variability over the past two decades. In this study, we seek to identify the possible linkage between regional sea level and Pacific climate variability from altimetry-based sea level data (1993-2012) and further investigate how the Pacific sea level has changed spatially and temporally over the past 60 years from long-term sea level reconstruction data (1953-2008). Based on the same method as Zhang and Church (2012), the Inter-annual Climate Index (ICI) associated with the El $Ni{\tilde{n}}o-Southern$ Oscillation (ENSO) and the Decadal Climate Index (DCI) associated with Pacific Decadal Oscillation (PDO) are defined and then the multiple variable linear regression is used to analyze quantitatively the impact of inter-annual and decadal climate variability on the regional sea levels in the Pacific. During the altimeter period, the ICI that represents ENSO influence on inter-annual time scales strongly impacts in a striking east-west "see-saw mode" on sea levels across the tropical Pacific. On the other hand, the decadal sea level pattern that is linked to the DCI has a broad meridional structure that is roughly symmetric in the equator with its North Pacific expression being similar to the PDO, which largely contributes to a positive SLR trend in the western Pacific and a negative trend in the eastern Pacific over the two most recent decades. Using long-term sea level reconstruction data, we found that the Pacific sea levels have fluctuated in the past over inter-annual and decadal time scales and that strong regional differences are presented. Of particular interest is that the SLR reveals a decadal shift and presents an opposite trend before and after the mid-1980s; i.e., a declining (rising) trend in the western (eastern) Pacific before the mid-1980s, followed by a rising (declining) trend from the mid-1980s onward in the western (eastern) Pacific. This result indicates that the recent SLR patterns revealed from the altimeters have been persistent at least since the mid-1980s.

Sociological Approach of Wood Culture (사회학적 측면에서의 목재문화에 관한 연구)

  • Hur, Gyongtae
    • Journal of the Korean Wood Science and Technology
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    • v.33 no.1 s.129
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    • pp.63-76
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    • 2005
  • Wood-culture is new paradigm which is substituted for the cement culture, and the study of wood-culture should keep pace with not only the study of a engineering science but also a sociological study to form a theory system. The purpose of this study is to suggest the method of sociological approach of the wood culture which have not yet tried at home and abroad; in view of structural-functionalism, systemical-functionalism, conflict theory, social-change theory by analyzing cases in Korea. In view of structural-functionalism, social system consists of cognition system, institution system, life system and technology system. These sub-systems fulfill the function of what-should-be, reasonability, reality and development. In view of systemical-functionalism, according to the acknowledgment and spreading proccess of the wood usefulness, wood culture system consists of the individual system, organizational system and the social system. In view of conflict theory, the society which has the wood culture can be classified into three types. The one is society which the traditional wood culture is declining and the cement culture is spreading. The other one is society which the cement culture is declining and the traditional wood culture is spreading. Another is Finally the society which the two type balance with. In view of social-change theory, the society can be classified into three types. The one is society which the wood culture is proceeding to the cement culture. The other is society which the cement culture is proceeding to the wood culture. Another is society which the wood culture changes itself. Finally, from a view of changing level, the society can be classified into three types: the micro-change, the middle-level-change, and the macro-change. It's need to study wood culture systemically in view of engineering and sociological science. And then it will be possible to make 'wood culture theory system'.

A Qualitative Analysis on Supervisors' Dysfunctional Leadership Behaviors, Antecedents, and Results (상사의 역기능 리더십 행동, 선행요인 그리고 결과에 대한 질적 분석)

  • Im, Chang-Hyun;Lee, Hee-Su
    • Journal of vocational education research
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    • v.30 no.4
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    • pp.1-22
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    • 2011
  • Paradoxically, leadership has not only positive effects but also negative effects. The purpose of this study is to examine supervisors' dysfunctional leadership behaviors, antecedents and results in order to draw HRD implications for protecting organizations and employees from dysfunctional leaders and provide implications for leadership development. A qualitative research method based on semi-organized interviews with 28 employees from S-group was used. The results of this study show that the dysfunctional leadership behaviors were associated with ten behavioral categories: belittling and insulting the subordinates, authoritative and arbitrary behaviors, self-aggrandizement, biased preference for certain personnel, arrogance, micro-managing, inability to change and adapt, discordance between words and actions, over-dependance on supervisor, lack of ethics and values. Dysfunctional leadership behaviors were casually attributed to 'personal traits & experience', 'task characteristics', and 'internal & external environments of the organization'. Finally, the results of supervisor's dysfunctional leadership behaviors on employees and the organizational effects were 'increased turnover rate', 'declining work efficiency', 'collapsing morale', 'retraining innovative thinking', 'passive working culture', 'discouraging organizational vitality', 'discouraging organizational synergy', 'losing loyalty' and 'declining trust on supervisor'.

Mutagenicity of Human Urine Excreted after Ingestion of Roast Beef (구운고기를 섭취한 후 배설된 사람 뇨의 돌연변이 유발성물질(Mutagenicity)에 관하여)

  • Shin, Dong-Gu;Kim, Jung-Hye;Kim, Jae-Ryong
    • Journal of Yeungnam Medical Science
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    • v.4 no.2
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    • pp.105-111
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    • 1987
  • This study was undertaken to observe the mutagenic occurrence in urine excreted after the ingestion of roast beef. Two healthy nonsmoker persons of both sex were selected for this test, employing two strains(TA98, TA100) of Salmonella typhimurium according to Ames' method. The mutagenic activity began to appear in urine of both sex three hours after ingestion of 300g of roast beef, gradually increasing until 6 hours and declining thereafter.

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Emissions Limits and Measures for Reducing Exhaust Emissions in Marine Diesel Engines (박용 디젤기관의 배기규제 및 배기 배출물 저감 대책)

  • 배명환
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.3
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    • pp.471-486
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    • 2001
  • The principal trends in the course of emission control legislation are reviewed in this paper. In order to keep such a regulation, moreover, an inquiry ito the concrete technical possibility is conducted through review articles, Also, the composition of exhaust gases emitted from a marine diesel engine are investigated as several samples and the measures that can satisfy the value of regulation are handled with laying stress on the control methods discussed to date. It was concluded that various combined systems can be made to reduce NOx emissions without deteriorating substantially navigation costs since many technologies for reducing NOx emissions are being developed. All heat engines suffer from SOx emissions. There are two methods for reducing SOx emissions: desulfurization from exhaust gas and removal of sulfur composition from fuel oil. However it is necessary to watch the development of these technologies to evaluate which method is more favorable. Heat engines have a big problem in the regulation of environmental pollution from exhaust emissions. In the near future, however, diesel engines may be superior to other heat engines, owing to the high thermal efficiency, although the sales of individual models in dises engines may be prosperous and declining.

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System Dynamic Model Study of Public Trust on Nuclear Regulation Policy (원자력 규제정책에 대한 국민신뢰도 평가 SD모델 연구)

  • Kwak, Mi-Aie;Cha, Hyun-Ju;Kim, Sung-Hyun;Jung, Kwan-Yong
    • Korean System Dynamics Review
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    • v.16 no.1
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    • pp.53-74
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    • 2015
  • The purpose of this paper is to simulate public trust on nuclear regulation policy. The first of all, public trust variables and the model were developed and analysed by system dynamic method. The model are consisted of the operator safety culture level, regulatory competence levels, the public satisfaction and public trust level. The scenario is made up three type which base scenario, the system operator's safety culture level and accident event level. First. the simulation results of standard scenario shows that rapidly declining public satisfaction and trust level of the national safety after Japan's nuclear accident in November 2011. Second, operator safety culture level and simulated divided into three levels. The results showed that a greater impact on the public satisfaction if bad than good case. Finally, the size of the accident was simulated divided into three levels levels(no accident, medium, serious accidents). the results showed a weak effect against the regulatory capacity and safety performance levels but showed a significant impact on public satisfaction and confidence level.

Estimation on the Total Added Value of Household Production : The Extended Concept of Production from Non-SNA (확대된 생산개념를 적용한 가계생산의 부가가치산정)

  • 윤소영
    • Journal of the Korean Home Economics Association
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    • v.42 no.7
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    • pp.131-143
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    • 2004
  • The purpose of this paper is to prepare a satellite account of the household sector that is reflected in the current national income account by approving the economic activities of unpaid household labor as production activity and estimating its value. The study produced three results. First, as different methods of evaluation can be useful according to different study goals or the contents of related policies, it is unreasonable to present a single result for estimating unpaid household labor. This study, therefore, presented the values of housework based on 5 methods, ranging from 124 to 150 trillion won. Second, to input the added value of household production from the fixed capital (household durable goods), this study adopted the declining balance method used in the Korea National Statistical Office. As a result, the total consumption of fixed capital was estimated at approximately 18.8 trillion won. Third, the total added value of unpaid household labor was estimated to range from 143 to 169 trillion wens. The amount is a production value excluded from the SNA which needs to be formed as a separate household satellite account. The ratio of this total value added was 30-35.4 percents to the 1999 GDP in Korea(477 trillion wens).

Measurement and Correction of PCB Alignment Error for Screen Printer Using Machine Vision (1) (머신비전을 이용한 PCB 스크린인쇄기의 정렬오차측정 및 위치보정 (1))

  • 신동원
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.6
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    • pp.88-95
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    • 2003
  • This paper presents the measurement and correction method of PCB alignment errors for PCB screen printer. Electronic equipment is getting smaller and yet must satisfy high performance standard. Therefore, there is a great demand for PCB with high density. However conventional PCB screen printer doesn't have enough accuracy to accommodate the demand fur high-resolution circuit pattern and high-density mounting capacity of electronic chips. It is because the alignment errors of PCB occur when it is loaded to the screen printer. Therefore, this study focuses on the development of the system which is able to measure and correct alignment errors with high-accuracy. An automatic optical inspection part measures the PCB alignment errors using machine vision, and the high-accuracy 3-axis stage makes correction for these errors. This system used two CCD cameras to get images of two fiducial marks of PCB. The geometrical relationship between PCB, cameras, and xy$\theta$ stage is derived, and analytical equations for alignment errors are also obtained. The unknown parameters including camera declining angles and etc. can be obtained by initialization process. Finally, the proposed algorithm is verified by experiments by using test bench.

High performance pervaporative desalination of saline waters using Na-X zeolite membrane

  • Malekpour, Akbar;Nasiri, Hamed
    • Membrane and Water Treatment
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    • v.8 no.5
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    • pp.437-448
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    • 2017
  • A high quality Na-X zeolite membrane was synthesized on a seeded ${\alpha}-alumina$ disc by the secondary growth method. Structural characterization was done by X-ray spectroscopy, FT-IR spectroscopy, SEM and AFM imaging. The performance evaluation of the membrane was firstly tested in separation of glucose/water solutions by pervaporation process. There was obtained a separation factor $182.7{\pm}8.8$, while the flux through the membrane was $3.6{\pm}0.3kg\;m^{-2}\;h^{-1}$. The zeolite membrane was then used for desalination of aqueous solutions consisting of $Na^+$, $Ca^{2+}$, $Cs^+$ and $Sr^{2+}$ because of the importance of these ions in water and wastewater treatments. The effects of some parameters such as temperature and solution concentration on the desalination process were studied for investigating of diffusion/adsorption mechanism in membrane separation. Finally, high water fluxes ranged from 2 up to $9kg\;m^{-2}\;h^{-1}$ were obtained and the rejection factors were resulted more than 95% for $Na^+$ and $Ca^{2+}$ and near to 99% for $Cs^+$ and $Sr^{2+}$. Based on the results, fluxes were significantly improved due to convenient passage of water molecules from large pores of NaX, while the fouling was declining dramatically. Based on the results, NaX zeolite can efficiently use for the removal of different cations from wastewaters.

Development of PCR-Based Screening Methods for Macrolide Type Polyketides in Actinomycetes

  • Hyun, Chang-Gu;Suh, Joo-Won
    • Journal of Applied Biological Chemistry
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    • v.42 no.3
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    • pp.119-124
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    • 1999
  • About two thirds of the naturally occurring antibiotics have been discovered from actinomycetes. Therefore, the probability of discovering further new antibiotics from actinomycetes is declining as many known metabolites are isolated repeatedly. However, various efforts leave been made in order to enhance the probability of discovering novel compounds. In the present study, we have developed new screening strategies based on the antibiotic biosynthetic pathway, and the genetic information, utilizing polymerase chain reaction. We have selected macrolide type polyketides. In order to divide the ansamycin group antibotic of macrolide type polyketides, we have selected 3-amino-5-hydroxybenzoic acid (AHBA) moiety which contains a biosynthetically unique structural element in the group as a target molecules. Oligonucleotide primers were designed to amplify DNA fragments of macrolide type polyketide synthase and AHBA synthase genes from fourteen actinomycetes species. This method was successfully applied to all three of the known macrolide type polyketide produccing actinomycetes tested. In addition, it also identified the presence of potential macrolide type polyketide producing genes from seven actinomycetes that were known to produce none of macrolide type polyketides, and AHBA biosynthetic genes in one actinomycetes. This technique is potentially useful for the screening of new antibiotices and cloning of their biosynthetic genes.

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