• Title/Summary/Keyword: analytical studies

Search Result 1,979, Processing Time 0.036 seconds

Studies on the Electrochemical Behavior of Heavy Lanthanide Ions and the Synthesis, Characterization of Heavy Metal Chelate Complexes(II). Synthesis and Characterization of Eight Coordinate Tungsten(IV) and Cerium(IV) Chelate Complex (무거운 란탄이온의 전기화학적 거동 및 중금속이온의 킬레이트형 착물의 합성 및 특성에 관한 연구(제2보). 8배위 텅스텐(IV)과 세륨(IV)의 킬레이트형 착물의 합성 및 특성)

  • Kang, Sam Woo;Chang, Choo Wan;Suh, Moo Yul;Lee, Doo Youn;Choi, Won Jong
    • Analytical Science and Technology
    • /
    • v.5 no.1
    • /
    • pp.41-49
    • /
    • 1992
  • An attempt was made to prepare two series of tetrakis eight-coordinate tungsten(IV) and cerium(IV) complexes containing the 5,7-dichloro-8-quinolinol(N:${\pi}$-acceptor atom, O:${\pi}$-donor atom) ligand. Tetrakis eight-coordinate tungsten(IV) complex of 2-mercaptopyrimidine(N:${\pi}$-acceptor atom, S:${\pi}$-donor atom) ligand have also been prepared. And the new series of mixed-ligand eight-coordinate tungsten(IV) complexes containing bidentate ligands 5,7-dichloro-8-quinolinol and 2-mercaptopyrimidine have been prepared, isolated by TLC and characterized. $W(dcq)_4$, $W(dcq)_3(mpd)_1$, $W(dcq)_2(mpd)_2$, $W(dcq)_1W(dcq)_3$ and $W(mpd)_4$ complexes of MLCT absorption band appeared to 710nm, 680nm, 625nm, 581nm, and 571nm(${\varepsilon}\;max={\sim}>{\times}10^4$) on low-energy respectively. The specific absorption wave length of $Ce(dcq)_4$ is appeared 520nm(${\varepsilon}\;max={\sim}>{\times}10^4$). The Chemical shift values by proton of coordinated position appeared to $W(dcq)_4$ [$H_2:8.9ppm$]; $W(dcq)_3(mpd)_1$ [$H_2:9.3$,$H_6:9.2ppm$]; $W(dcq)_2(mpd)_2$ [$H_2:9.7$,$H_6:8.95ppm$]; $W(dcq)_1(mpd)_3$ [$H_2:9.8$,$H_6:9.4ppm$]; $W(mpd)_4$ [$H_6:8.8ppm$]; $Ce(dcq)_4$ [$H_2:9.3ppm$] with $^1H$-NMR. The inertness of mixed-ligand eight coordinate tungsten(IV) complexes have been investigated by UV-Vis. spectroscopic method in dimethylsulfoxide at $90^{\circ}C$. The inertness of $W(dcq)_n(mpd)_{4-n}$ complexes showed the following order, $W(dcq)_3(mpd)_1;k_{obs.}=3.8{\times}10^{-6}$ > $W(mpd)_4;k_{obs.}=6.0{\times}10^{-6}$ > $W(dcq)_4;k_{obs.}=6.4{\times}10^{-6}$ > $W(dcq)_2(mpd)_2;k_{obs.}=7.0{\times}10^{-6}$ > $W(dcq)_1(mpd)_3;k_{obs.}=1.7{\times}10^{-5}$, which showed the inertness until 16days, 10days, 9days, 8days, and 4days. The $W(mpd)_4$ is very inert as $k_{obs.}=3.6{\times}10^{-6}$(16days) in xylene at $90^{\circ}C$ and $k_{obs.}=6.0{\times}10^{-6}$(10days) in DMSO at $90^{\circ}C$.

  • PDF

The Impact of the Internet Channel Introduction Depending on the Ownership of the Internet Channel (도입주체에 따른 인터넷경로의 도입효과)

  • Yoo, Weon-Sang
    • Journal of Global Scholars of Marketing Science
    • /
    • v.19 no.1
    • /
    • pp.37-46
    • /
    • 2009
  • The Census Bureau of the Department of Commerce announced in May 2008 that U.S. retail e-commerce sales for 2006 reached $ 107 billion, up from $ 87 billion in 2005 - an increase of 22 percent. From 2001 to 2006, retail e-sales increased at an average annual growth rate of 25.4 percent. The explosive growth of E-Commerce has caused profound changes in marketing channel relationships and structures in many industries. Despite the great potential implications for both academicians and practitioners, there still exists a great deal of uncertainty about the impact of the Internet channel introduction on distribution channel management. The purpose of this study is to investigate how the ownership of the new Internet channel affects the existing channel members and consumers. To explore the above research questions, this study conducts well-controlled mathematical experiments to isolate the impact of the Internet channel by comparing before and after the Internet channel entry. The model consists of a monopolist manufacturer selling its product through a channel system including one independent physical store before the entry of an Internet store. The addition of the Internet store to this channel system results in a mixed channel comprised of two different types of channels. The new Internet store can be launched by the independent physical store such as Bestbuy. In this case, the physical retailer coordinates the two types of stores to maximize the joint profits from the two stores. The Internet store also can be introduced by an independent Internet retailer such as Amazon. In this case, a retail level competition occurs between the two types of stores. Although the manufacturer sells only one product, consumers view each product-outlet pair as a unique offering. Thus, the introduction of the Internet channel provides two product offerings for consumers. The channel structures analyzed in this study are illustrated in Fig.1. It is assumed that the manufacturer plays as a Stackelberg leader maximizing its own profits with the foresight of the independent retailer's optimal responses as typically assumed in previous analytical channel studies. As a Stackelberg follower, the independent physical retailer or independent Internet retailer maximizes its own profits, conditional on the manufacturer's wholesale price. The price competition between two the independent retailers is assumed to be a Bertrand Nash game. For simplicity, the marginal cost is set at zero, as typically assumed in this type of study. In order to explore the research questions above, this study develops a game theoretic model that possesses the following three key characteristics. First, the model explicitly captures the fact that an Internet channel and a physical store exist in two independent dimensions (one in physical space and the other in cyber space). This enables this model to demonstrate that the effect of adding an Internet store is different from that of adding another physical store. Second, the model reflects the fact that consumers are heterogeneous in their preferences for using a physical store and for using an Internet channel. Third, the model captures the vertical strategic interactions between an upstream manufacturer and a downstream retailer, making it possible to analyze the channel structure issues discussed in this paper. Although numerous previous models capture this vertical dimension of marketing channels, none simultaneously incorporates the three characteristics reflected in this model. The analysis results are summarized in Table 1. When the new Internet channel is introduced by the existing physical retailer and the retailer coordinates both types of stores to maximize the joint profits from the both stores, retail prices increase due to a combination of the coordination of the retail prices and the wider market coverage. The quantity sold does not significantly increase despite the wider market coverage, because the excessively high retail prices alleviate the market coverage effect to a degree. Interestingly, the coordinated total retail profits are lower than the combined retail profits of two competing independent retailers. This implies that when a physical retailer opens an Internet channel, the retailers could be better off managing the two channels separately rather than coordinating them, unless they have the foresight of the manufacturer's pricing behavior. It is also found that the introduction of an Internet channel affects the power balance of the channel. The retail competition is strong when an independent Internet store joins a channel with an independent physical retailer. This implies that each retailer in this structure has weak channel power. Due to intense retail competition, the manufacturer uses its channel power to increase its wholesale price to extract more profits from the total channel profit. However, the retailers cannot increase retail prices accordingly because of the intense retail level competition, leading to lower channel power. In this case, consumer welfare increases due to the wider market coverage and lower retail prices caused by the retail competition. The model employed for this study is not designed to capture all the characteristics of the Internet channel. The theoretical model in this study can also be applied for any stores that are not geographically constrained such as TV home shopping or catalog sales via mail. The reasons the model in this study is names as "Internet" are as follows: first, the most representative example of the stores that are not geographically constrained is the Internet. Second, catalog sales usually determine the target markets using the pre-specified mailing lists. In this aspect, the model used in this study is closer to the Internet than catalog sales. However, it would be a desirable future research direction to mathematically and theoretically distinguish the core differences among the stores that are not geographically constrained. The model is simplified by a set of assumptions to obtain mathematical traceability. First, this study assumes the price is the only strategic tool for competition. In the real world, however, various marketing variables can be used for competition. Therefore, a more realistic model can be designed if a model incorporates other various marketing variables such as service levels or operation costs. Second, this study assumes the market with one monopoly manufacturer. Therefore, the results from this study should be carefully interpreted considering this limitation. Future research could extend this limitation by introducing manufacturer level competition. Finally, some of the results are drawn from the assumption that the monopoly manufacturer is the Stackelberg leader. Although this is a standard assumption among game theoretic studies of this kind, we could gain deeper understanding and generalize our findings beyond this assumption if the model is analyzed by different game rules.

  • PDF

Health Assessment of the Nakdong River Basin Aquatic Ecosystems Utilizing GIS and Spatial Statistics (GIS 및 공간통계를 활용한 낙동강 유역 수생태계의 건강성 평가)

  • JO, Myung-Hee;SIM, Jun-Seok;LEE, Jae-An;JANG, Sung-Hyun
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.18 no.2
    • /
    • pp.174-189
    • /
    • 2015
  • The objective of this study was to reconstruct spatial information using the results of the investigation and evaluation of the health of the living organisms, habitat, and water quality at the investigation points for the aquatic ecosystem health of the Nakdong River basin, to support the rational decision making of the aquatic ecosystem preservation and restoration policies of the Nakdong River basin using spatial analysis techniques, and to present efficient management methods. To analyze the aquatic ecosystem health of the Nakdong River basin, punctiform data were constructed based on the position information of each point with the aquatic ecosystem health investigation and evaluation results of 250 investigation sections. To apply the spatial analysis technique, the data need to be reconstructed into areal data. For this purpose, spatial influence and trends were analyzed using the Kriging interpolation(ArcGIS 10.1, Geostatistical Analysis), and were reconstructed into areal data. To analyze the spatial distribution characteristics of the Nakdong River basin health based on these analytical results, hotspot(Getis-Ord Gi, $G^*_i$), LISA(Local Indicator of Spatial Association), and standard deviational ellipse analyses were used. The hotspot analysis results showed that the hotspot basins of the biotic indices(TDI, BMI, FAI) were the Andong Dam upstream, Wangpicheon, and the Imha Dam basin, and that the health grades of their biotic indices were good. The coldspot basins were Nakdong River Namhae, the Nakdong River mouth, and the Suyeong River basin. The LISA analysis results showed that the exceptional areas were Gahwacheon, the Hapcheon Dam, and the Yeong River upstream basin. These areas had high bio-health indices, but their surrounding basins were low and required management for aquatic ecosystem health. The hotspot basins of the physicochemical factor(BOD) were the Nakdong River downstream basin, Suyeong River, Hoeya River, and the Nakdong River Namhae basin, whereas the coldspot basins were the upstream basins of the Nakdong River tributaries, including Andong Dam, Imha Dam, and Yeong River. The hotspots of the habitat and riverside environment factor(HRI) were different from the hotspots and coldspots of each factor in the LISA analysis results. In general, the habitat and riverside environment of the Nakdong River mainstream and tributaries, including the Nakdong river upstream, Andong Dam, Imha Dam, and the Hapcheon Dam basin, had good health. The coldspot basins of the habitat and riverside environment also showed low health indices of the biotic indices and physicochemical factors, thus requiring management of the habitat and riverside environment. As a result of the time-series analysis with a standard deviation ellipsoid, the areas with good aquatic ecosystem health of the organisms, habitat, and riverside environment showed a tendency to move northward, and the BOD results showed different directions and concentrations by the year of investigation. These aquatic ecosystem health analysis results can provide not only the health management information for each investigation spot but also information for managing the aquatic ecosystem in the catchment unit for the working research staff as well as for the water environment researchers in the future, based on spatial information.

Dynamic Limit and Predatory Pricing Under Uncertainty (불확실성하(不確實性下)의 동태적(動態的) 진입제한(進入制限) 및 약탈가격(掠奪價格) 책정(策定))

  • Yoo, Yoon-ha
    • KDI Journal of Economic Policy
    • /
    • v.13 no.1
    • /
    • pp.151-166
    • /
    • 1991
  • In this paper, a simple game-theoretic entry deterrence model is developed that integrates both limit pricing and predatory pricing. While there have been extensive studies which have dealt with predation and limit pricing separately, no study so far has analyzed these closely related practices in a unified framework. Treating each practice as if it were an independent phenomenon is, of course, an analytical necessity to abstract from complex realities. However, welfare analysis based on such a model may give misleading policy implications. By analyzing limit and predatory pricing within a single framework, this paper attempts to shed some light on the effects of interactions between these two frequently cited tactics of entry deterrence. Another distinctive feature of the paper is that limit and predatory pricing emerge, in equilibrium, as rational, profit maximizing strategies in the model. Until recently, the only conclusion from formal analyses of predatory pricing was that predation is unlikely to take place if every economic agent is assumed to be rational. This conclusion rests upon the argument that predation is costly; that is, it inflicts more losses upon the predator than upon the rival producer, and, therefore, is unlikely to succeed in driving out the rival, who understands that the price cutting, if it ever takes place, must be temporary. Recently several attempts have been made to overcome this modelling difficulty by Kreps and Wilson, Milgram and Roberts, Benoit, Fudenberg and Tirole, and Roberts. With the exception of Roberts, however, these studies, though successful in preserving the rationality of players, still share one serious weakness in that they resort to ad hoc, external constraints in order to generate profit maximizing predation. The present paper uses a highly stylized model of Cournot duopoly and derives the equilibrium predatory strategy without invoking external constraints except the assumption of asymmetrically distributed information. The underlying intuition behind the model can be summarized as follows. Imagine a firm that is considering entry into a monopolist's market but is uncertain about the incumbent firm's cost structure. If the monopolist has low cost, the rival would rather not enter because it would be difficult to compete with an efficient, low-cost firm. If the monopolist has high costs, however, the rival will definitely enter the market because it can make positive profits. In this situation, if the incumbent firm unwittingly produces its monopoly output, the entrant can infer the nature of the monopolist's cost by observing the monopolist's price. Knowing this, the high cost monopolist increases its output level up to what would have been produced by a low cost firm in an effort to conceal its cost condition. This constitutes limit pricing. The same logic applies when there is a rival competitor in the market. Producing a high cost duopoly output is self-revealing and thus to be avoided. Therefore, the firm chooses to produce the low cost duopoly output, consequently inflicting losses to the entrant or rival producer, thus acting in a predatory manner. The policy implications of the analysis are rather mixed. Contrary to the widely accepted hypothesis that predation is, at best, a negative sum game, and thus, a strategy that is unlikely to be played from the outset, this paper concludes that predation can be real occurence by showing that it can arise as an effective profit maximizing strategy. This conclusion alone may imply that the government can play a role in increasing the consumer welfare, say, by banning predation or limit pricing. However, the problem is that it is rather difficult to ascribe any welfare losses to these kinds of entry deterring practices. This difficulty arises from the fact that if the same practices have been adopted by a low cost firm, they could not be called entry-deterring. Moreover, the high cost incumbent in the model is doing exactly what the low cost firm would have done to keep the market to itself. All in all, this paper suggests that a government injunction of limit and predatory pricing should be applied with great care, evaluating each case on its own basis. Hasty generalization may work to the detriment, rather than the enhancement of consumer welfare.

  • PDF

A Study on Commodity Asset Investment Model Based on Machine Learning Technique (기계학습을 활용한 상품자산 투자모델에 관한 연구)

  • Song, Jin Ho;Choi, Heung Sik;Kim, Sun Woong
    • Journal of Intelligence and Information Systems
    • /
    • v.23 no.4
    • /
    • pp.127-146
    • /
    • 2017
  • Services using artificial intelligence have begun to emerge in daily life. Artificial intelligence is applied to products in consumer electronics and communications such as artificial intelligence refrigerators and speakers. In the financial sector, using Kensho's artificial intelligence technology, the process of the stock trading system in Goldman Sachs was improved. For example, two stock traders could handle the work of 600 stock traders and the analytical work for 15 people for 4weeks could be processed in 5 minutes. Especially, big data analysis through machine learning among artificial intelligence fields is actively applied throughout the financial industry. The stock market analysis and investment modeling through machine learning theory are also actively studied. The limits of linearity problem existing in financial time series studies are overcome by using machine learning theory such as artificial intelligence prediction model. The study of quantitative financial data based on the past stock market-related numerical data is widely performed using artificial intelligence to forecast future movements of stock price or indices. Various other studies have been conducted to predict the future direction of the market or the stock price of companies by learning based on a large amount of text data such as various news and comments related to the stock market. Investing on commodity asset, one of alternative assets, is usually used for enhancing the stability and safety of traditional stock and bond asset portfolio. There are relatively few researches on the investment model about commodity asset than mainstream assets like equity and bond. Recently machine learning techniques are widely applied on financial world, especially on stock and bond investment model and it makes better trading model on this field and makes the change on the whole financial area. In this study we made investment model using Support Vector Machine among the machine learning models. There are some researches on commodity asset focusing on the price prediction of the specific commodity but it is hard to find the researches about investment model of commodity as asset allocation using machine learning model. We propose a method of forecasting four major commodity indices, portfolio made of commodity futures, and individual commodity futures, using SVM model. The four major commodity indices are Goldman Sachs Commodity Index(GSCI), Dow Jones UBS Commodity Index(DJUI), Thomson Reuters/Core Commodity CRB Index(TRCI), and Rogers International Commodity Index(RI). We selected each two individual futures among three sectors as energy, agriculture, and metals that are actively traded on CME market and have enough liquidity. They are Crude Oil, Natural Gas, Corn, Wheat, Gold and Silver Futures. We made the equally weighted portfolio with six commodity futures for comparing with other commodity indices. We set the 19 macroeconomic indicators including stock market indices, exports & imports trade data, labor market data, and composite leading indicators as the input data of the model because commodity asset is very closely related with the macroeconomic activities. They are 14 US economic indicators, two Chinese economic indicators and two Korean economic indicators. Data period is from January 1990 to May 2017. We set the former 195 monthly data as training data and the latter 125 monthly data as test data. In this study, we verified that the performance of the equally weighted commodity futures portfolio rebalanced by the SVM model is better than that of other commodity indices. The prediction accuracy of the model for the commodity indices does not exceed 50% regardless of the SVM kernel function. On the other hand, the prediction accuracy of equally weighted commodity futures portfolio is 53%. The prediction accuracy of the individual commodity futures model is better than that of commodity indices model especially in agriculture and metal sectors. The individual commodity futures portfolio excluding the energy sector has outperformed the three sectors covered by individual commodity futures portfolio. In order to verify the validity of the model, it is judged that the analysis results should be similar despite variations in data period. So we also examined the odd numbered year data as training data and the even numbered year data as test data and we confirmed that the analysis results are similar. As a result, when we allocate commodity assets to traditional portfolio composed of stock, bond, and cash, we can get more effective investment performance not by investing commodity indices but by investing commodity futures. Especially we can get better performance by rebalanced commodity futures portfolio designed by SVM model.

A Study on the Technical and Administrative Innovation of Library Organization in the Perspective of the Contingency Theory (도서관조직의 기술혁신 및 행정혁신에 관한 조직상황론적 연구)

  • Hong Hyun-Jin
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.25
    • /
    • pp.343-388
    • /
    • 1993
  • The ability of any organization to innovate itself in a rapid change of environment means the existence of the organization. Innovative activity is achieved in different ways according to the objectives of organization. the characteristics of external environmental factors. and various attributes in organization. In the present study. all the existing approaches to the innovative nature of organization were synthetically compared to each other and evaluated: then. for a more rational approach. a research model was built and suggested by establishing the inclusive variables of the innovative nature of library organization and categorizing the types of such nature. Additionally. an empirical. analytical study on such a model was done. That is. paying regard to the fact that innovation has basically a close relation with the circumstantial factors of organization. synthetic, circumstantial relations were clarified. considering the external environmental factors and internal characteristics of organization. In the study. the innovation of library organization was seen in two parts i.e .. the feasible degree of technical innovation and the feasible degree of administrative innovation. Regarding the types of innovative implementation. according to the feasible degree of innovation, four types such as a stationary type. technic-oriented type, organization-oriented type. and technical-socio systematic type were classified. There were nine independent variables-i.e., the scale of organization. available resources of the organization, formalization, differentiation, specialization. decentralization, recognizant degree of the technical attribute. degree of response to the change of technical environment, and professional activities. There were three subordinate variables - i.e., technical innovation, administrative innovation. and the performance of organization. Through establishment of such variables, the factors which might influence the innovation of library organization were understood, and with the types of the innovative implementation of library organization being classified according to the feasible degree of innovation. the characteristics of library organization were reviewed in the light of each type. Also. the performance of library organization according to the types of the innovative implementation of library organization was analyzed. and the relations between the types of innovative implementation according to circumstantial variables and the performance of library organization were clarified. In order to clarify the adequacy of the research model in the methodology of empirical study, data were collected from 72 university libraries and 38 special libraries. and for a hypothetical test of the research model. an analysis of correlations, a stepwise regression analysis. and One Way ANOVA were utilized. The following are the major results or findings from the study 1) It appeared there is a trend that the bigger the scale of organization and available resources are, the more active the professional activity of the managerial class is, and the higher the recognizant degree of technical environment (recognizant degree of technical attributes and the degree of response t9 the change of technical environment) is, the higher the feasible degree of innovation becomes. 2) It appeared that among the variables influencing the feasible degree of technical innovation, the order from the variable influencing most was first, the recognizant degree of technical innovation: second, the available resources of organization: and third, professional activity. Regarding the variables influencing the feasible degree of administrative innovation from the most influential variable, it appeared they were the available resources of organization, the differentiation of organization. and the degree of response to the change of technical environment. 3) It appeared that the higher the educational level of the managerial class is, the more active the professional activity becomes. It seemed there is a trend that the group of library managers whose experience as a librarian was at the middle level(three years to six years of experience) was more active in research activity than the group of library managers whose experience as a librarian was at a higher level(more than ten years). Also, it appeared there is a trend that the lower the age of library managers is, the higher the recognizant degree of technical attributes becomes. and the group of library managers whose experience as a librarian was at the middle level (three years to six years of experience) recognized more affirmatively the technical aspect than the group of library managers whose experience as a librarian was at a higher level(more than 10 years). Also, it appeared that, when the activity of the professional association and research activity are active, the recognizant degree of technology becomes higher, and as a result. it influences the innovative nature of organization(the feasible degree of technical innovation and the feasible degree of administrative innovation). 4) As a result of the comparison and analysis of the characteristics of library organization according to the types of innovative implementation of library organization. it was indicated there is a trend that the larger the available resources of library organization, the higher the organic nature of organization such as differentiation. decentralization, etc., and the higher the level of the operation of system development, the more the type of the innovative implementation of library organization becomes the technical-socio systematic type which is higher both in the practical degrees of technical innovation and administrative innovation. 5) As a result of the comparison and analysis of the relations between the types of innovative implementation and the performance of organization, it appeared that the order from the highest performance of organization is the technical-socio systematic type, then the technic-oriented type, the organization­oriented type, and finally the stationary type which is lowest in such performance. That is, it demonstrated that, since the performance of library organization is highest in the library of the technical-socio systematic type while it is lowest in the library whose practical degrees in both technical innovation and administrative innovation are low, the performance of library organization differs significantly according to the types of innovative implementation of library organization. The present study has extracted the factors influencing innovation, classified systematically the types of innovative implementation, and inferred the synthetical, circumstantial correlations between the types and the performance of organization, and empirically inspected those factors. However, due to the present study's restrictive matters and the limit of the research design, results from the study should be more prudently interpreted. Also, the present study, as an investigative study of the types of innovative implementation, with few preceding studies, requires more complete hypothetical inference based on the results of the present study. In other words, if more systematical studies are given to understanding the relations, it will devote the suggestion and demonstration of a more useful theory.

  • PDF

Predicting the Direction of the Stock Index by Using a Domain-Specific Sentiment Dictionary (주가지수 방향성 예측을 위한 주제지향 감성사전 구축 방안)

  • Yu, Eunji;Kim, Yoosin;Kim, Namgyu;Jeong, Seung Ryul
    • Journal of Intelligence and Information Systems
    • /
    • v.19 no.1
    • /
    • pp.95-110
    • /
    • 2013
  • Recently, the amount of unstructured data being generated through a variety of social media has been increasing rapidly, resulting in the increasing need to collect, store, search for, analyze, and visualize this data. This kind of data cannot be handled appropriately by using the traditional methodologies usually used for analyzing structured data because of its vast volume and unstructured nature. In this situation, many attempts are being made to analyze unstructured data such as text files and log files through various commercial or noncommercial analytical tools. Among the various contemporary issues dealt with in the literature of unstructured text data analysis, the concepts and techniques of opinion mining have been attracting much attention from pioneer researchers and business practitioners. Opinion mining or sentiment analysis refers to a series of processes that analyze participants' opinions, sentiments, evaluations, attitudes, and emotions about selected products, services, organizations, social issues, and so on. In other words, many attempts based on various opinion mining techniques are being made to resolve complicated issues that could not have otherwise been solved by existing traditional approaches. One of the most representative attempts using the opinion mining technique may be the recent research that proposed an intelligent model for predicting the direction of the stock index. This model works mainly on the basis of opinions extracted from an overwhelming number of economic news repots. News content published on various media is obviously a traditional example of unstructured text data. Every day, a large volume of new content is created, digitalized, and subsequently distributed to us via online or offline channels. Many studies have revealed that we make better decisions on political, economic, and social issues by analyzing news and other related information. In this sense, we expect to predict the fluctuation of stock markets partly by analyzing the relationship between economic news reports and the pattern of stock prices. So far, in the literature on opinion mining, most studies including ours have utilized a sentiment dictionary to elicit sentiment polarity or sentiment value from a large number of documents. A sentiment dictionary consists of pairs of selected words and their sentiment values. Sentiment classifiers refer to the dictionary to formulate the sentiment polarity of words, sentences in a document, and the whole document. However, most traditional approaches have common limitations in that they do not consider the flexibility of sentiment polarity, that is, the sentiment polarity or sentiment value of a word is fixed and cannot be changed in a traditional sentiment dictionary. In the real world, however, the sentiment polarity of a word can vary depending on the time, situation, and purpose of the analysis. It can also be contradictory in nature. The flexibility of sentiment polarity motivated us to conduct this study. In this paper, we have stated that sentiment polarity should be assigned, not merely on the basis of the inherent meaning of a word but on the basis of its ad hoc meaning within a particular context. To implement our idea, we presented an intelligent investment decision-support model based on opinion mining that performs the scrapping and parsing of massive volumes of economic news on the web, tags sentiment words, classifies sentiment polarity of the news, and finally predicts the direction of the next day's stock index. In addition, we applied a domain-specific sentiment dictionary instead of a general purpose one to classify each piece of news as either positive or negative. For the purpose of performance evaluation, we performed intensive experiments and investigated the prediction accuracy of our model. For the experiments to predict the direction of the stock index, we gathered and analyzed 1,072 articles about stock markets published by "M" and "E" media between July 2011 and September 2011.

The Relationships among Patient's Perception, Patient's Satisfaction of Nursing Service Quality and Revisiting intention (간호서비스 질에 대한 환자의 인식과 만족도 및 재방문의도와의 관계)

  • Lee, Sun-Ah
    • Journal of Korean Academy of Nursing Administration
    • /
    • v.4 no.2
    • /
    • pp.307-319
    • /
    • 1998
  • This study is an empirical investigation and study on the measurement of nursing service quality as perceived by patients. A series of H1. H2. H3 alternative hypotheses were tested using a sample of 250 patients in Taegu City. Korea. HI hypothese were tested for application of five component of service quality (SERVQlTAL and SE RPERF : tangiblity. reliability. responsiveness. accessibility. understandability) in Taegu area Hospitals. Validity test - the five components of service quality were rearranged into two components of service quality (personal factor. nonpersonal factor). Although SERVQUAL was verified in USA. application for five components of service quality in Korea indicated that it need more analytical studies. Nobody can deny the fact that the recent growth of the nursing service quality is one of the most important driving forces of hospital management. In many hospitals. the nursing quality charges more than 50% of the medical service quality. As a result. many hospital managers should be enormous interests in the investment potentiality of the nursing service. However. doesn't many researchers invest their time and effort on the research of the quality control in nursing service. Nursing service management is the process to satisfy customer's desires and expectations through the various service activities. Presently nursing service are being faced with three Common tasks of improving quality of nursing service. competitively differential advantage and productivity because of quantitative expansion of Nursing service. Such a phenomenon is also found in our medical service industry. resulting from increasing demands for medical service owing to national medical insurance policy and consumer's attitude change emphasizing prevention of illness. excessiveness of medical facilities in large cities and increasing medical lawsuits due to influence of consumerism. Therefore. under such circumstances. this research on nursing service is conducted from nursing managements to improve the nursing service quality problems faced by medical institutions. The results of this theoretical/empirical research are as follows: 1. Nursing service Quality is regarded as patients' perceived quality and evaluated on the basis (5 dimension) of technical and functional quality. 2. Nursing service Quality is a concept of patients evaluation on the measurable multi-dimensions intrinsic and extrinsic attributes of service. 3. Nursing service Quality is conceptually defined as the difference between the perceived service and the expected service. 4. Korean consumers trend to evaluate nursing service quality based on such dimensions as responsiveness and reliability. understandability. accessibility. tangibility. 5. After analyzing whether or not there are some differences in respective medical institution. it was found that there are significant difference on understandability. reliability. communicability. courtesy. competence. 6. After analyzing the difference between the expected nursing service and the nursing perceived service, it was found that the expected nursing service is higher than the perceived service in every medical institution. 7. HI hypothesis was tested with regard to the validity test between SERVQUAL and SERVPERF in nursing service quality. The result of validity test between SERVQUAL and SERVPERF was found to have differential result. That is the R2 of SERVPERF is higher than that of SERVQUAL. Therefore. HI was verified in nursing management. H2. H3 hypotheses were tested whether or not the nursing service quality and patient satisfaction is the preceding variable. The result of H2 hypothes is that the nursing service quality is the preceding variable of patient satisfaction and the patient satisfaction is that of revisiting intention. After analyzing whether or not there is any differences on the demographic variable of five nursing service quality factor. it was found that there are statistically significant differences on communicability and courtesy at the sex. understand ability. accessibility and tangibility at the age. understandability at the academic background respectively.

  • PDF

The Effects of Service Employee's Surface Acting on Counterproductive Work Behavior: The Mediating Roles of Emotional Exhaustion (서비스 종업원의 표면행위가 반생산적 과업행동에 미치는 효과에 관한 연구: 감정소모의 매개효과를 중심으로)

  • Kang, Seong-Ho;Chay, Jong-Hak;Lee, Ji-Ae;Hur, Won-Moo
    • Journal of Distribution Science
    • /
    • v.14 no.2
    • /
    • pp.73-82
    • /
    • 2016
  • Purpose - Counterproductive work behavior(CWB) was typically categorized according to the behavior whether it targets other people(i.e., interpersonal CWB: I-CWB). Employing organizations(i.e., organizational CWB: O-CWB) has emerged as major concerns among researchers, managers, and the general public. An abundance of researches has informed us about the understanding for the antecedents of CWB, whereas little is known about the antecedents of CWB directed distribution service in employee's emotional labor. Therefore, the purpose of this research is to propose a research model in which surface acting enhances emotional exhaustion as an emotional labor strategy, which eventually increases counterproductive work behavior(including I-CWM and O-CWB). Research design, data, and methodology - This empirical research data were gathered from the samples of full time frontline hotel employees(including front office, call center, food/beverage, concierge, and room service) in South Korea. Six hotels were selected ranged from four to five stars, including privately owned and joint-venture properties. A convenience sampling method was used to select hotels. Full time frontline hotel employees from the six hotels were surveyed using a self-administered instrument for data collection. With the strong support of hotel managers, a total of 300 questionnaires were distributed, and 252 responses were collected indicating a response rate of 84.0%. In the process of working with the 252 samples, structural equation modeling is employed to test research hypotheses(H1: The relationship between surface acting and Interpersonal counterproductive work behavior(I-CWB) is mediated by emotional exhaustion, H2: The relationship between surface acting and organizational counterproductive work behavior(O-CWB) is mediated by emotional exhaustion). SPSS 18.0 and M-Plus 7.31 software were used for the data analysis. Descriptive statistics were used to assess the distribution of the employee profiles and correlations between factors. M-Plus 7.31 software was used to test the model fit, validity, and reliability of the factors, significance of the relationship between factors, and the effects of factors in the model. Results - To test our mediation hypotheses, we used an analytical strategy suggested by Preacher & Hayes (2008) and Shrout & Bolger (2002). This mediation approach directly tests the indirect effect between the predictor and the criterion variables through the mediator via a bootstrapping procedure. Thus, it addresses some weaknesses associated with the Sobel test. We found that surface acting was positively related to emotional exhaustion. Furthermore, emotional exhaustion was a significant predictor from the two kinds of counterproductive work behavior. In addition, surface acting was not significantly associated with the two kinds of counterproductive work behavior. These results indicated that the surface acting by frontline hotel employees was associated with higher emotional exhaustion, which is related with higher interpersonal counterproductive work behavior(I-CWB) and organizational counterproductive work behavior(O-CWB). In sum, we confirmed that the positive relationship between surface acting and the two kinds of counterproductive work behavior was fully mediated by emotional exhaustion. Conclusions - The current research broadens the conceptual work and empirical studies in counterproductive work behavior literature by representing a fundamental mechanism that how surface acting affects counterproductive work behavior.

Analytical Studies on The Useful Characters Affecting The Lodging Resistance of Wheat and Barley Varieties (맥류의 도복에 관여하는 유용형질의 분석에 관한 연구)

  • Chang-Hwan Cho
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.11
    • /
    • pp.105-117
    • /
    • 1972
  • This experiment has been made to study the relationship between several characters affecting the field lodging and to establish some useful standards for selection of lodging resistant varieties and to classify the degree of lodging resistance in wheat and barley varieties of different sources. The experiment was carried at the Crop Experiment Station, Suwon in 1968. The results obtained are summarized as followings. a. The lodging index modified with bending moment of culm at breaking seemed to be the most useful character in checking the lodging resistance. Highly significant positive correlation (Barley; r=0.40-0.67, Wheat; r=0.46-0.68) was obtained between the lodging index and actual field lodging. b. Between two essential components expressing bending stiffness of the culm, the bending moment at breaking and secondary moment of inertia, a highly significant positive correlation (Barley; r=0.59, wheat; r=0.46-0.53) was observed. c. The bending stiffness of culm got stronger as the dry weight per unit culm, which express the quantity of accumulated dry matters in culm, increased. The correlation coefficient between those two factors was 0.35 to 0.40 in barley and 0.33 to 0.76 in wheat respectively. d. In both wheat and barley, highly significant negative correlation between lodging index and the other factors such as dry weight per unit culm (Barley; r=-0. 51 to -0.70, Wheat; r=-0.65 to -0.83) and bending moment of culm at breaking (Barley; r=-0.29 to -0.69, Wheat: r=-0.54 to -0.89) were observed. Particulary, weight of culm at breaking, secondary moment of inertia and section modulus showed significant negative correlation with lodging index in wheat. e. Outside diameter of culm expressed more intimate relationship with physical characteristics of culm than inside diameter and also showed highly significant correlation with weight of culm at breaking (Barley; r=0.42-0.56, Wheat; r=0.39-0.44) and with bending moment of culm at breaking (Barley; r=0.40-0.41, Wheat; r=0.38-0.49) and with secondary moment of inertia (Barley; r=0.56-0.57, Wheat; r=0.28-0.98) and with section modulus (Wheat; r=0.22-0.96). Between the thickness of culm and physical characteristics of culm also showed the positive correlation. f. There was positive correlation between the culm length and actual field lodging in several groups of variety among the varieties tested. But the culm length seemed to undesirable as a selection measure for the selection of the lodging resistant variety considering the stiffness of culm. g. In classification of lodging resistance for the varieties tested, many Korean barley varieties expressed excellent lodging resistant than wheat, but most of the wheat and barley varieties from Japan considered quite resistant to lodging. h. In selection of lodging resistant varieties, lodging index lower than 1.67 in barley and 1. 76 in wheat considered highly resistant to actual field lodging.

  • PDF