• Title/Summary/Keyword: Timing Ability

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THE INFLUENCE OF OBTURATION TIMING AND THICKNESS OF MINERAL TRIOXIDE AGGREGATE ON SEALING ABILITY OF CANAL WITH OPEN APEX (근관충전 시기와 MINERAL TRIOXIDE AGGREGATE의 APICAL MATRIX두께에 따른 치근단 밀폐도의 평가)

  • Kwak, Kyung-In;Park, Dong-Sung;Yoo, Hyeon-Mee;Oh, Tae-Seok
    • Restorative Dentistry and Endodontics
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    • v.25 no.4
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    • pp.536-542
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    • 2000
  • 임상에서 점차 Mineral Trioxide Aggregate (MTA)에 대한 우수성이 소개되면서, apical matrix로의 사용은 주목할 만하다 할 수 있다. 본 연구의 목적은 개방형근관에서 MTA가 apical matrix로 사용될 때의 치근단 밀폐효과를 알아 보고, 근관충전의 시기와 matrix의 두께가 치근단 밀폐에 미치는 영향을 치근단 미세누출의 측면과 matrix탈락빈도의 측면에서 관찰하고자 하는 것이다. 개방형 근관을 재현하고자 45개의 발거된 단근치에 #90크기로 근단공을 형성하였고, 투명레진등을 이용하여 치근단 병소를 갖는 치조골을 재현한 후, 4개의 실험 군과 1개의 대조 군으로 분류하였다. A군: 2mm두께의 MTA matrix 형성후, 열연화된 Gutta-percha와 AH26 sealer를 이용하여 즉시 근관충전. B군: 2mm 두께의 MTA matrix 형성후, A군과 같은 방법으로 24시간 후 근관충전. C군: 4mm 두께의 MTA matrix 형성후, A군과 같은 방법으로 즉시 근관충전. D군: 4mm 두께의 MTA matrix 형성후, A군과 같은 방법으로 24시간 후 근관충전. 대조군: matrix를 사용하지 않고 열연화된 Gutta-percha와 AH26 sealer를 이용하여 근관충전하였다. Matrix의 탈락이 있는 경우 기록하고 완전 수세 후 다시 시행하였다. 색소침투정도의 평가를 위해 methylene blue에 치아를 48시간 침수시킨 후 협설로 양분하였다. 각 시편들을 고배율 현미경 관찰 후 비디오촬영 하였고, digitalized image analysing program을 이용하여 두명의 관찰자가 누출의 정도를 평가한 후, One-way ANOVA로 통계적 유의성을 검증하여 다음과 같은 결과를 얻었다. 1. Matrix를 사용한 실험 군이 matrix를 사용하지 않은 대조 군에 비해 유의성 있게 낮은 누출을 보였다(p<0.05). 그러나 근관충전시기와 matrix의 두께를 달리한 실험군 내에서는 누출에 유의성 있는 차이가 나타나지 않았다. 2. 모든 실험군에서 gutta-percha를 이용한 근관충전의 시기에 matrix탈락 및 gutta-percha의 압출은 발생하지 않았다.

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CAPACITY EXPANSION MODELING OF WATER SUPPLY IN A PLANNING SUPPORT SYSTEM FOR URBAN GROWTH MANAGEMENT (도시성장관리를 위한 계획지원체계에서 상수도의 시설확장 모델링)

  • Hyong-Bok, Kim
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 1995.12a
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    • pp.9-21
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    • 1995
  • A planning support system enhances our ability to use water capacity expansion as an urban growth management strategy. This paper reports the development of capacity expansion modeling of water supply as part of the continuing development of such a planning support system (PEGASUS: Planning Environment for Generation and Analysis of Spatial Urban Systems) to incorporate water supply, This system is designed from the understanding that land use and development drive the demand for infrastructure and infrastructure can have a significant influence on the ways in which land is developed and used. Capacity expansion Problems of water supply can be solved in two ways: 1) optimal control theory, and 2) mixed integer nonlinear programming (MINLP). Each method has its strengths and weaknesses. In this study the MINLP approach is used because of its strength of determining expansion sizing and timing simultaneously. A dynamic network optimization model and a water-distribution network analysis model can address the dynamic interdependence between water planning and land use planning. While the water-distribution network analysis model evaluates the performance of generated networks over time, the dynamic optimization model chooses alternatives to meet expanding water needs. In addition, the user and capacity expansion modeling-to-generate-alternatives (MGA) can generate alternatives. A cost benefit analysis module using a normalization technique helps in choosing the most economical among those alternatives. GIS provide a tool for estimating the volume of demanded water and showing results of the capacity expansion model.

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Analysis of Science Lesson Plan of Pre-Service Elementary Teachers about Condensation (초등 예비교사의 응결 차시에 대한 과학 수업 설계 분석)

  • Sung, SeungMin;Yeo, Sang-Ihn
    • Journal of Science Education
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    • v.45 no.2
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    • pp.172-186
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    • 2021
  • The purpose of this study is to analyze the science lesson plan of pre-service elementary teachers about condensation. Pre-service elementary school teachers in A national university of education was included in this study. Through the analysis of prior research and expert review, a framework for analysis of science lesson plan of pre-service elementary teachers was derived. The results of the using the analysis frame are as follows: First, the ability to apply the instructional model in the science lesson plan about condensation differences in pre-service elementary teachers need to be enhanced due to deviations, and teaching on the exact understanding of condensation-related concepts of pre-service elementary teachers is also needed. Second, there is also a deviation of pre-service elementary teachers in the beginning, development, and finishing composition of lesson course, so feedback should be supplemented. Third, in the sub-domain of lesson environment, there was a demand for specific know-how on the lesson environment. Therefore, support is needed for related PCK growth. Fourth, the sub-domain of lesson evaluation have a variety of perspectives on timing and subjects, and some missing about learning objectives in the composition of evaluation content are found to require complementary teaching. In order to improve this situation, it was found that there was a need to prepare conditions for improving science teaching professionalism of pre-service elementary teachers through in-depth discussions on the teaching methods and organization related to science education in the university of education course.

Rhythmic Tapping Task Performance in Children With Autism Spectrum Disorder: A Meta-Analysis (자폐스펙트럼장애 아동 대상 리드믹 운동과제 평가 연구 메타분석)

  • Yoo, Ga Eul;Yoon, Ye Eun
    • Journal of Music and Human Behavior
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    • v.16 no.1
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    • pp.47-72
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    • 2019
  • This study reviewed and analyzed English-written studies using a rhythmic tapping task for motor control of children with autism spectrum disorder (ASD). Inclusion criteria for the participants were children with ASD and typically developing (TD) children. The keywords used for the outcome variables included rhythmic tapping, timed movement, and synchronization. Ten studies were included in the final analysis. The included studies were analyzed in terms of target variables, auditory stimuli, and measurements. A meta-analysis was also conducted to examine how children with ASD performed rhythmic tapping tasks compared to children with TD. In the identified studies, five variables were used: timed movement control, timing reproduction, bimanual coordination, synchronization, and interpersonal synchronization. It was found that rhythmic tapping performance was analyzed in terms of accuracy and precision of the movement and reported as significantly correlated to social skills measures. The meta-analysis results showed that there were no significant differences between the ASD and TD groups in continuing rhythmic movements when the presented auditory stimuli ended, whereas there were significant group differences in their ability to maintain their motor performance consistently and to synchronize with auditory cue or with others. These results support the rhythmic tapping task as an effective measure for not only motor control but also social skills development in children with ASD.

Sustainable Development and Sustainability Marketing - Integration of customer and socio-ecological aspect in Marketing concept - (글로벌 기업 환경 변화의 새로운 패러다임으로서 지속가능한 발전과 마케팅 - 지속가능마케팅의 의사결정 지향적 컨셉 -)

  • Nam, Sang-Min;Kim, Jong-Ho;Noh, Jung-Koo
    • Journal of Global Scholars of Marketing Science
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    • v.17 no.3
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    • pp.83-108
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    • 2007
  • Since the 1992 UN Conference for Environment and Development held in Rio de Jaineiro, Sustainable Development has become the global thesis. More than 170 countries signed the Agenda 21 for the sustainable action plan, and adopted the sustainability concept as the key concept of dealing with the environmental, social, ethical, and economic problem. Sustainability is one of the main marketing challenges in the 21st century. By integrating social and ecological criteria, marketing may can make valuable contributions to sustainable development. Regarding the sustainability marketing, it is difficult to find the domestic marketing research on the thesis of sustainable development, and this is the definite evidence that the Korean marketing researchers do not realize the importance of the thesis of sustainable development which is internationally suggested as the new paradigm of change. The purpose of this study is to build the conceptual background and explore the research direction in order to introduce and adopt the concept of sustainable development in the domestic marketing research field. The present paper proposes a comprehensive conception of sustainability marketing, defined by six step: analysis of social-ecological problems; analysis of consumer behavior; normative sustainability marketing; strategic sustainability marketing; instrumental sustainability marketing; and transformative sustainability marketing. The aim of the paper are to clarify the concept of sustainability marketing. To accomplish this research purpose we discuss the sustainable development which is the conceptual background of sustainability marketing, analyze the characteristics of the sustainability marketing, and finally summarize the research results and present the suggestions for further research. Sustainability marketing embraces the idea of sustainable development, a development that meets the needs of the present without compromising the ability of future generation to meet their own needs. Sustainability Marketing goes beyond conventional marketing thinking. If marketing is about satisfying customer needs and building profitable relationships with customers, sustainability marketing may be defined as building and maintaining sustainable relationships with customers, the social environment and natural environment. By creating social and environmental value, sustainability marketing tries to deliver and increase customer value. Sustainability Marketing aims at creating customer value, social value and environmental value. Sustainability marketing integrates social and ecological criteria into the whole process of marketing, and can be differentiated in six steps: (1) Analysis of the social and ecological problems, generally and specifically with respect to products which satisfy customer needs and wants; (2) Analysis of customer behavior with special aspect to social and ecological concerns; (3) Corporate commitments to sustainable development in the mission statement, development of sustainability visions, formulation of sustainable principles and guideline, setting of socio-ecological marketing objectives and goals (normative aspects of sustainability marketing); (4) Sustainability segmentation, targeting and positioning, and timing of market entry(strategic aspects of sustainability marketing); (5)Integration of social and ecological criteria into the marketing-mix, i.e. products, services and brands, pricing, distribution and communication(instrumental aspects of sustainability marketing); (6) Participation in public and political change processes, which transform existing institutions towards sustainability(transformative aspects of sustainability marketing). The first two steps begin with an analysis of the company situation. In sustainability marketing it is crucial not just to know consumer needs and wants, but also to find out about the ecological and social problems of products along their whole life cycle. The intersection of socio-ecological problems and consumer wants sets the ground for sustainability marketing. Step three to five describe the implementation of sustainability marketing. Social and ecological criteria are fully integrated into the mission statement, strategies and marketing-mix. Step six is one of the specifics of sustainability marketing. It is about the commitment of company to sustainable development and their active participation in public and political processes in order to change the existing framework in favor of sustainability.

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Development of Market Growth Pattern Map Based on Growth Model and Self-organizing Map Algorithm: Focusing on ICT products (자기조직화 지도를 활용한 성장모형 기반의 시장 성장패턴 지도 구축: ICT제품을 중심으로)

  • Park, Do-Hyung;Chung, Jaekwon;Chung, Yeo Jin;Lee, Dongwon
    • Journal of Intelligence and Information Systems
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    • v.20 no.4
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    • pp.1-23
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    • 2014
  • Market forecasting aims to estimate the sales volume of a product or service that is sold to consumers for a specific selling period. From the perspective of the enterprise, accurate market forecasting assists in determining the timing of new product introduction, product design, and establishing production plans and marketing strategies that enable a more efficient decision-making process. Moreover, accurate market forecasting enables governments to efficiently establish a national budget organization. This study aims to generate a market growth curve for ICT (information and communication technology) goods using past time series data; categorize products showing similar growth patterns; understand markets in the industry; and forecast the future outlook of such products. This study suggests the useful and meaningful process (or methodology) to identify the market growth pattern with quantitative growth model and data mining algorithm. The study employs the following methodology. At the first stage, past time series data are collected based on the target products or services of categorized industry. The data, such as the volume of sales and domestic consumption for a specific product or service, are collected from the relevant government ministry, the National Statistical Office, and other relevant government organizations. For collected data that may not be analyzed due to the lack of past data and the alteration of code names, data pre-processing work should be performed. At the second stage of this process, an optimal model for market forecasting should be selected. This model can be varied on the basis of the characteristics of each categorized industry. As this study is focused on the ICT industry, which has more frequent new technology appearances resulting in changes of the market structure, Logistic model, Gompertz model, and Bass model are selected. A hybrid model that combines different models can also be considered. The hybrid model considered for use in this study analyzes the size of the market potential through the Logistic and Gompertz models, and then the figures are used for the Bass model. The third stage of this process is to evaluate which model most accurately explains the data. In order to do this, the parameter should be estimated on the basis of the collected past time series data to generate the models' predictive value and calculate the root-mean squared error (RMSE). The model that shows the lowest average RMSE value for every product type is considered as the best model. At the fourth stage of this process, based on the estimated parameter value generated by the best model, a market growth pattern map is constructed with self-organizing map algorithm. A self-organizing map is learning with market pattern parameters for all products or services as input data, and the products or services are organized into an $N{\times}N$ map. The number of clusters increase from 2 to M, depending on the characteristics of the nodes on the map. The clusters are divided into zones, and the clusters with the ability to provide the most meaningful explanation are selected. Based on the final selection of clusters, the boundaries between the nodes are selected and, ultimately, the market growth pattern map is completed. The last step is to determine the final characteristics of the clusters as well as the market growth curve. The average of the market growth pattern parameters in the clusters is taken to be a representative figure. Using this figure, a growth curve is drawn for each cluster, and their characteristics are analyzed. Also, taking into consideration the product types in each cluster, their characteristics can be qualitatively generated. We expect that the process and system that this paper suggests can be used as a tool for forecasting demand in the ICT and other industries.

Study on Operating System Improvements to the Competitiveness of Busan Port (부산항 경쟁력 강화를 위한 운영체제 개선에 관한 연구)

  • Seo, Su-Wan
    • Journal of Korea Port Economic Association
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    • v.34 no.4
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    • pp.191-208
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    • 2018
  • This paper focuses on the integration aspect of operators to determine an improvement strategy for the operating system to enhance competitiveness of Busan Port. This Study proposes the following alternatives: valuation standards for the integration of operators, the road map for the integration period, the scope and role setting of integrated operators' participation of Busan Port Authority(BPA), and the separation and linkage North Port and the New Port operators. First, the valuation standards for operator integration should be based on international standards. Additionally quantitative factors such as financial situation, business performance and participating companies' profitability, and the qualitative factors such as management ability, technology, and labor relations should be considered. Second, the timing of North Port's operator integration should be prioritized in the short term in conjunction with the commencement of its phase 2-4, 2-5, and 2-6. The integration of New Port operators should provide a road map for a relatively long-term perspective. Third, the participation of BPA' integrated operators should be considered in terms of publicity as a policy coordinator between terminals and by pursuing the profitability of entering into overseas business by fostering Korean global terminal operators. The scope and role of participation ensures that the experience and technology of the terminal operation business is maximized. Fourth, because physically intergrating the North Port' operator into a single corporate form is difficult, initially establishing a special purpose company to maximize the effect of the integrated operation is necessary. Then, the operators decided to convert to a holding company given the termination of the lease term contract with the State or BPA, and ultimately proposed a merger into a single corporation.

A study on Convergence Weapon Systems of Self propelled Mobile Mines and Supercavitating Rocket Torpedoes (자항 기뢰와 초공동 어뢰의 융복합 무기체계 연구)

  • Lee, Eunsu;Shin, Jin
    • Maritime Security
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    • v.7 no.1
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    • pp.31-60
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    • 2023
  • This study proposes a new convergence weapon system that combines the covert placement and detection abilities of a self-propelled mobile mine with the rapid tracking and attack abilities of supercavitating rocket torpedoes. This innovative system has been designed to counter North Korea's new underwater weapon, 'Haeil'. The concept behind this convergence weapon system is to maximize the strengths and minimize the weaknesses of each weapon type. Self-propelled mobile mines, typically placed discreetly on the seabed or in the water, are designed to explode when a vessel or submarine passes near them. They are generally used to defend or control specific areas, like traditional sea mines, and can effectively limit enemy movement and guide them in a desired direction. The advantage that self-propelled mines have over traditional sea mines is their ability to move independently, ensuring the survivability of the platform responsible for placing the sea mines. This allows the mines to be discreetly placed even deeper into enemy lines, significantly reducing the time and cost of mine placement while ensuring the safety of the deployed platforms. However, to cause substantial damage to a target, the mine needs to detonate when the target is very close - typically within a few yards. This makes the timing of the explosion crucial. On the other hand, supercavitating rocket torpedoes are capable of traveling at groundbreaking speeds, many times faster than conventional torpedoes. This rapid movement leaves little room for the target to evade, a significant advantage. However, this comes with notable drawbacks - short range, high noise levels, and guidance issues. The high noise levels and short range is a serious disadvantage that can expose the platform that launched the torpedo. This research proposes the use of a convergence weapon system that leverages the strengths of both weapons while compensating for their weaknesses. This strategy can overcome the limitations of traditional underwater kill-chains, offering swift and precise responses. By adapting the weapon acquisition criteria from the Defense force development Service Order, the effectiveness of the proposed system was independently analyzed and proven in terms of underwater defense sustainability, survivability, and cost-efficiency. Furthermore, the utility of this system was demonstrated through simulated scenarios, revealing its potential to play a critical role in future underwater kill-chain scenarios. However, realizing this system presents significant technical challenges and requires further research.

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A Study on Industries's Leading at the Stock Market in Korea - Gradual Diffusion of Information and Cross-Asset Return Predictability- (산업의 주식시장 선행성에 관한 실증분석 - 자산간 수익률 예측 가능성 -)

  • Kim Jong-Kwon
    • Proceedings of the Safety Management and Science Conference
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    • 2004.11a
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    • pp.355-380
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    • 2004
  • I test the hypothesis that the gradual diffusion of information across asset markets leads to cross-asset return predictability in Korea. Using thirty-six industry portfolios and the broad market index as our test assets, I establish several key results. First, a number of industries such as semiconductor, electronics, metal, and petroleum lead the stock market by up to one month. In contrast, the market, which is widely followed, only leads a few industries. Importantly, an industry's ability to lead the market is correlated with its propensity to forecast various indicators of economic activity such as industrial production growth. Consistent with our hypothesis, these findings indicate that the market reacts with a delay to information in industry returns about its fundamentals because information diffuses only gradually across asset markets. Traditional theories of asset pricing assume that investors have unlimited information-processing capacity. However, this assumption does not hold for many traders, even the most sophisticated ones. Many economists recognize that investors are better characterized as being only boundedly rational(see Shiller(2000), Sims(2201)). Even from casual observation, few traders can pay attention to all sources of information much less understand their impact on the prices of assets that they trade. Indeed, a large literature in psychology documents the extent to which even attention is a precious cognitive resource(see, eg., Kahneman(1973), Nisbett and Ross(1980), Fiske and Taylor(1991)). A number of papers have explored the implications of limited information- processing capacity for asset prices. I will review this literature in Section II. For instance, Merton(1987) develops a static model of multiple stocks in which investors only have information about a limited number of stocks and only trade those that they have information about. Related models of limited market participation include brennan(1975) and Allen and Gale(1994). As a result, stocks that are less recognized by investors have a smaller investor base(neglected stocks) and trade at a greater discount because of limited risk sharing. More recently, Hong and Stein(1999) develop a dynamic model of a single asset in which information gradually diffuses across the investment public and investors are unable to perform the rational expectations trick of extracting information from prices. Hong and Stein(1999). My hypothesis is that the gradual diffusion of information across asset markets leads to cross-asset return predictability. This hypothesis relies on two key assumptions. The first is that valuable information that originates in one asset reaches investors in other markets only with a lag, i.e. news travels slowly across markets. The second assumption is that because of limited information-processing capacity, many (though not necessarily all) investors may not pay attention or be able to extract the information from the asset prices of markets that they do not participate in. These two assumptions taken together leads to cross-asset return predictability. My hypothesis would appear to be a very plausible one for a few reasons. To begin with, as pointed out by Merton(1987) and the subsequent literature on segmented markets and limited market participation, few investors trade all assets. Put another way, limited participation is a pervasive feature of financial markets. Indeed, even among equity money managers, there is specialization along industries such as sector or market timing funds. Some reasons for this limited market participation include tax, regulatory or liquidity constraints. More plausibly, investors have to specialize because they have their hands full trying to understand the markets that they do participate in

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