• Title/Summary/Keyword: Process-Based Model

Search Result 9,765, Processing Time 0.04 seconds

A study on the Degradation and By-products Formation of NDMA by the Photolysis with UV: Setup of Reaction Models and Assessment of Decomposition Characteristics by the Statistical Design of Experiment (DOE) based on the Box-Behnken Technique (UV 공정을 이용한 N-Nitrosodimethylamine (NDMA) 광분해 및 부산물 생성에 관한 연구: 박스-벤켄법 실험계획법을 이용한 통계학적 분해특성평가 및 반응모델 수립)

  • Chang, Soon-Woong;Lee, Si-Jin;Cho, Il-Hyoung
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.32 no.1
    • /
    • pp.33-46
    • /
    • 2010
  • We investigated and estimated at the characteristics of decomposition and by-products of N-Nitrosodimethylamine (NDMA) using a design of experiment (DOE) based on the Box-Behken design in an UV process, and also the main factors (variables) with UV intensity($X_2$) (range: $1.5{\sim}4.5\;mW/cm^2$), NDMA concentration ($X_2$) (range: 100~300 uM) and pH ($X_2$) (rang: 3~9) which consisted of 3 levels in each factor and 4 responses ($Y_1$ (% of NDMA removal), $Y_2$ (dimethylamine (DMA) reformation (uM)), $Y_3$ (dimethylformamide (DMF) reformation (uM), $Y_4$ ($NO_2$-N reformation (uM)) were set up to estimate the prediction model and the optimization conditions. The results of prediction model and optimization point using the canonical analysis in order to obtain the optimal operation conditions were $Y_1$ [% of NDMA removal] = $117+21X_1-0.3X_2-17.2X_3+{2.43X_1}^2+{0.001X_2}^2+{3.2X_3}^2-0.08X_1X_2-1.6X_1X_3-0.05X_2X_3$ ($R^2$= 96%, Adjusted $R^2$ = 88%) and 99.3% ($X_1:\;4.5\;mW/cm^2$, $X_2:\;190\;uM$, $X_3:\;3.2$), $Y_2$ [DMA conc] = $-101+18.5X_1+0.4X_2+21X_3-{3.3X_1}^2-{0.01X_2}^2-{1.5X_3}^2-0.01X_1X_2+0.07X_1X_3-0.01X_2X_3$ ($R^2$= 99.4%, 수정 $R^2$ = 95.7%) and 35.2 uM ($X_1$: 3 $mW/cm^2$, $X_2$: 220 uM, $X_3$: 6.3), $Y_3$ [DMF conc] = $-6.2+0.2X_1+0.02X_2+2X_3-0.26X_1^2-0.01X_2^2-0.2X_3^2-0.004X_1X_2+0.1X_1X_3-0.02X_2X_3$ ($R^2$= 98%, Adjusted $R^2$ = 94.4%) and 3.7 uM ($X_1:\;4.5\;$mW/cm^2$, $X_2:\;290\;uM$, $X_3:\;6.2$) and $Y_4$ [$NO_2$-N conc] = $-25+12.2X_1+0.15X_2+7.8X_3+{1.1X_1}^2+{0.001X_2}^2-{0.34X_3}^2+0.01X_1X_2+0.08X_1X_3-3.4X_2X_3$ ($R^2$= 98.5%, Adjusted $R^2$ = 95.7%) and 74.5 uM ($X_1:\;4.5\;mW/cm^2$, $X_2:\;220\;uM$, $X_3:\;3.1$). This study has demonstrated that the response surface methodology and the Box-Behnken statistical experiment design can provide statistically reliable results for decomposition and by-products of NDMA by the UV photolysis and also for determination of optimum conditions. Predictions obtained from the response functions were in good agreement with the experimental results indicating the reliability of the methodology used.

The Roles of Service Failure and Recovery Satisfaction in Customer-Firm Relationship Restoration : Focusing on Carry-over effect and Dynamics among Customer Affection, Customer Trust and Loyalty Intention Before and After the Events (서비스실패의 심각성과 복구만족이 고객-기업 관계회복에 미치는 영향 : 실패이전과 복구이후 고객애정, 고객신뢰, 충성의도의 이월효과 및 역학관계 비교를 중심으로)

  • La, Sun-A
    • Journal of Distribution Research
    • /
    • v.17 no.1
    • /
    • pp.1-36
    • /
    • 2012
  • Service failure is one of the major reasons for customer defection. As the business environment gets tougher and more competitive, a single service failure might bring about fatal consequences to a service provider or a firm. Sometimes a failure won't end up with an unsatisfied customer's simple complaining but with a wide-spread animosity against the service provider or the firm, leading to a threat to the firm's survival itself in the society. Therefore, we are in need of comprehensive understandings of complainants' attitudes and behaviors toward service failures and firm's recovery efforts. Even though a failure itself couldn't be fixed completely, marketers should repair the mind and heart of unsatisfied customers, which can be regarded as an successful recovery strategy in the end. As the outcome of recovery efforts exerted by service providers or firms, recovery of the relationship between customer and service provider need to put on the top in the recovery goal list. With these motivations, the study investigates how service failure and recovery makes the changes in dynamics of fundamental elements of customer-firm relationship, such as customer affection, customer trust and loyalty intention by comparing two time points, before the service failure and after the recovery, focusing on the effects of recovery satisfaction and the failure severity. We adopted La & Choi (2012)'s framework for development of the research model that was based on the previous research stream like Yim et al. (2008) and Thomson et al. (2005). The pivotal background theories of the model are mainly from relationship marketing and social relationships of social psychology. For example, Love, Emotional attachment, Intimacy, and Equity theories regarding human relationships were reviewed. As the results, when recovery satisfaction is high, customer affection and customer trust that were established before the service failure are carried over to the future after the recovery. However, when recovery satisfaction is low, customer-firm relationship that had already established in the past are not carried over but broken up. Regardless of the degree of recovery satisfaction, once a failure occurs loyalty intention is not carried over to the future and the impact of customer trust on loyalty intention becomes stronger. Such changes imply that customers become more prudent and more risk-aversive than the time prior to service failure. The impact of severity of failure on customer affection and customer trust matters only when recovery satisfaction is low. When recovery satisfaction is high, customer affection and customer trust become severity-proof. Interestingly, regardless of the degree of recovery satisfaction, failure severity has a significant negative influence on loyalty intention. Loyalty intention is the most fragile target when a service failure occurs no matter how severe the failure criticality is. Consequently, the ultimate goal of service recovery should be the restoration of customer-firm relationship and recovery of customer trust should be the primary objective to accomplish for a successful recovery performance. Especially when failure severity is high, service recovery should be perceived highly satisfied by the complainants because failure severity matters more when recovery satisfaction is low. Marketers can implement recovery strategies to enhance emotional appeals as well as fair treatments since the both impacts of affection and trust on loyalty intention are significant. In the case of high severity of failure, recovery efforts should be exerted to overreach customer expectation, designed to directly repair customer trust and elaborately designed in the focus of customer-firm communications during the interactional recovery process to affect customer trust rebuilding indirectly. Because it is a longer and harder way to rebuild customer-firm relationship for high severity cases, low recovery satisfaction cannot guarantee customer retention. To prevent customer defection due to service failure of high severity, unexpected rewards as a recovery will be likely to be useful since those will lead to customer delight or customer gratitude toward the service firm. Based on the results of analyses, theoretical and managerial implications are presented. Limitations and future research ideas are also discussed.

  • PDF

A Study on the Factors Affecting the Global Performance in Chinese Small and Medium Sized Enterprises (중국 중소기업의 글로벌 성과에 미치는 영향요인에 관한 연구)

  • Li, Jun-Jian;Kim, Tae-In
    • International Commerce and Information Review
    • /
    • v.14 no.3
    • /
    • pp.3-30
    • /
    • 2012
  • In the development process, small and medium-sized enterprises in China have shown their unique features and regularities which are closely related to China's national condition and economic characteristics. But in 2008, because of the global financial crisis which started in the USA, the rate of Chinese export and the rate of economic growth has evidently slowed. Due to shortage of funds, foreign orders fell, increase the value of RMB, lack of talented factors, Chinese SMEs are facing bankruptcy. In this context, the purpose of this study is to examine the effects of domestic and international market environment, the government assistance for entering overseas market, entrepreneur characteristics, etc. on the global performance. Based on these, a research model and some hypotheses were set up and tested by the multiple regression analysis with total 317 effective survey data. The results of this paper are as follows. First, a positive effect relation on the financial performance was shown for the companies with high domestic and international market environment in the aspect of market environment. According to such analysis result, it was found that the market environment in which SMEs belong to is a very important factor. Second, in the aspect of government export assistance related to overseas, market development showed a positive effect relation on the both financial and non-financial performance. However, the direct financial assistance showed a positive effect relation only on the non-financial performance. Overall, it was found that the government assistance program on entering overseas market is having significant effects on SMEs, but direct financial assistance have not achieved the desired results. Third, the innovative-ness and progressiveness of entrepreneur showed a positive effect relation on the global market performance. However, the risk-taking of entrepreneur only showed a negative effect relation on the non-financial performance. Overall, it was found that the entrepreneurship of SMEs is an important and influential factor. This is a result implying that the propensity of taking too much risk is not desirable based on the uncertainty of the global environment market. To sum up, this study confirmed that the market environment, the government assistance and entrepreneur characteristics, which are the major prerequisites of global performance, have effects on global performance.

  • PDF

The Analysis on the Relationship between Firms' Exposures to SNS and Stock Prices in Korea (기업의 SNS 노출과 주식 수익률간의 관계 분석)

  • Kim, Taehwan;Jung, Woo-Jin;Lee, Sang-Yong Tom
    • Asia pacific journal of information systems
    • /
    • v.24 no.2
    • /
    • pp.233-253
    • /
    • 2014
  • Can the stock market really be predicted? Stock market prediction has attracted much attention from many fields including business, economics, statistics, and mathematics. Early research on stock market prediction was based on random walk theory (RWT) and the efficient market hypothesis (EMH). According to the EMH, stock market are largely driven by new information rather than present and past prices. Since it is unpredictable, stock market will follow a random walk. Even though these theories, Schumaker [2010] asserted that people keep trying to predict the stock market by using artificial intelligence, statistical estimates, and mathematical models. Mathematical approaches include Percolation Methods, Log-Periodic Oscillations and Wavelet Transforms to model future prices. Examples of artificial intelligence approaches that deals with optimization and machine learning are Genetic Algorithms, Support Vector Machines (SVM) and Neural Networks. Statistical approaches typically predicts the future by using past stock market data. Recently, financial engineers have started to predict the stock prices movement pattern by using the SNS data. SNS is the place where peoples opinions and ideas are freely flow and affect others' beliefs on certain things. Through word-of-mouth in SNS, people share product usage experiences, subjective feelings, and commonly accompanying sentiment or mood with others. An increasing number of empirical analyses of sentiment and mood are based on textual collections of public user generated data on the web. The Opinion mining is one domain of the data mining fields extracting public opinions exposed in SNS by utilizing data mining. There have been many studies on the issues of opinion mining from Web sources such as product reviews, forum posts and blogs. In relation to this literatures, we are trying to understand the effects of SNS exposures of firms on stock prices in Korea. Similarly to Bollen et al. [2011], we empirically analyze the impact of SNS exposures on stock return rates. We use Social Metrics by Daum Soft, an SNS big data analysis company in Korea. Social Metrics provides trends and public opinions in Twitter and blogs by using natural language process and analysis tools. It collects the sentences circulated in the Twitter in real time, and breaks down these sentences into the word units and then extracts keywords. In this study, we classify firms' exposures in SNS into two groups: positive and negative. To test the correlation and causation relationship between SNS exposures and stock price returns, we first collect 252 firms' stock prices and KRX100 index in the Korea Stock Exchange (KRX) from May 25, 2012 to September 1, 2012. We also gather the public attitudes (positive, negative) about these firms from Social Metrics over the same period of time. We conduct regression analysis between stock prices and the number of SNS exposures. Having checked the correlation between the two variables, we perform Granger causality test to see the causation direction between the two variables. The research result is that the number of total SNS exposures is positively related with stock market returns. The number of positive mentions of has also positive relationship with stock market returns. Contrarily, the number of negative mentions has negative relationship with stock market returns, but this relationship is statistically not significant. This means that the impact of positive mentions is statistically bigger than the impact of negative mentions. We also investigate whether the impacts are moderated by industry type and firm's size. We find that the SNS exposures impacts are bigger for IT firms than for non-IT firms, and bigger for small sized firms than for large sized firms. The results of Granger causality test shows change of stock price return is caused by SNS exposures, while the causation of the other way round is not significant. Therefore the correlation relationship between SNS exposures and stock prices has uni-direction causality. The more a firm is exposed in SNS, the more is the stock price likely to increase, while stock price changes may not cause more SNS mentions.

Economic Loss Estimation of Mt. Baekdu Eruption Scenarios (백두산 화산 분화 시나리오에 따른 경제적 손실 평가)

  • Yu, Soonyoung;Lee, Yun-Jung;Yoon, Seong-Min;Choi, Ki-Hong
    • Economic and Environmental Geology
    • /
    • v.47 no.3
    • /
    • pp.205-217
    • /
    • 2014
  • As Mt. Backdu is expected to erupt, the social and economic impacts of the eruption on the Korean peninsula as well as on the world become a research topic of interest. If the volcano erupts, South Korea can be directly impacted by volcanic ash, which will bring out secondary damages in various ways. Given that the direct damage is a basis to estimate indirect and secondary damages, this paper was to review a method to estimate direct damages, called catastrophe risk models, and estimate the direct damages of available eruption scenarios of Mt. Baekdu. Based on the results, the damages by volcanic ash will occur mostly around Gangwon province if the Mt. Backdu erupts. Thus the inventory lists and their damage functions of Gangwon provinces were collected. In particular agricultural and forestry products were surveyed based on the land use. Direct damages were estimated using volcanic ash distribution of eruption scenarios, inventory information and their damage functions. In result, a scenario in winter caused the damage of 299.8 billion KRW (20.4% of total agricultural production in 2010) and 28.9 billion KRW (9.0% of total forestry production in 2010) in agriculture and forestry, respectively. The damages in agriculture was larger, and it is due to the damage functions which show the agricultural products are more vulnerable to volcanic ash than forestry products. Also the agricultural production (1,471.7 billion KRW in 2010) are more than 4.5 times the forestry production (322.3 billion KRW in 2010) in Gangwon province. Inje and Gangnung had the most damages in the scenario in winter. Inje had the most damage due to the thick ash deposit (8.5 mm in average) despite the low production. On the other hand, Goseong had a low damage compared to the ash thickness larger than 20mm, owing to the low production. The direct damage estimated through this process can be used to estimate indirect damages.

Study on Implementation Measures of Provincial Self-governing Police System : Focusing on the Implication from Enlargement of Work Scope of Self-governing Police of Jeju Province (광역자치경찰제의 정착방안에 관한 연구 - 제주자치경찰의 사무확대에 대한 시사점을 중심으로 -)

  • Kim, Seong-Hee
    • Korean Security Journal
    • /
    • no.59
    • /
    • pp.37-69
    • /
    • 2019
  • According to viewpoints of researchers and stakeholders, various opinions can be suggested on self-governing police system. Therefore, success of Korean self-governing police system will be defending on how to balance among conflicting values such as Empowerment, Political neutrality, Financial issues, Comprehensive competence in maintaining public safety. Before the launching of self-governing police system nation-wide, the experience of Jeju provincial police will be valuable model case. In specific, enlargement of work scope of self-governing police in Jeju province which has been introduced since last year will be a useful reference. There is more pessimism about self-governing police of Jeju province so far. However, this perspective is mostly based on the issue regarding hardwares such as manpower, equipment, law and organization. Issues regarding softwares such as organizational culture, operation system and work process need more attention to evaluate self-governing police system properly. To mark the first year after enlargement of work scope of Jeju police, this study demonstrate the overall result and implications of self-governing police of Jeju province based on documents, statistics, reports and media reports. In result, several preconditions are needed to implement the self-governing police system nation-wide successfully. 1. Strengthen the link between local government and local police 2. Establish the foundation for collaboration of state and local police 3. Enhance the aspect of citizen autonomy in local level 4. Reinforcing the capability of handling situation of state and local police 5. Invigorating the inter-organizational working group to operate self-governing police system effectively. The self-governing police system is unclosed topic to discuss. After this study, in-depth studies should be followed with more resources. Particularly, additional perspective including redundancy and equity need to be considered regarding self-governing police. By getting with the changes of macroscopic trends - lowbirth and aging, the fourth industrial revolution and possible reunification of north and south Koreas - these studies should suggest the long-term blueprint of self-governing police system of Korea.

Development and Evaluation of a Nutritional Risk Screening Tool (NRST) for Hospitalized Patients (입원환자의 영양불량위험 검색도구의 개발 및 평가)

  • Han, Jin-Soon;Lee, Song-Mi;Chung, Hye-Kyung;Ahn, Hong-Seok;Lee, Seung-Min
    • Journal of Nutrition and Health
    • /
    • v.42 no.2
    • /
    • pp.119-127
    • /
    • 2009
  • Malnutrition of hospitalized patients can adversely affect clinical outcomes and cost. Several nutritional screening tools have been developed to identify patients with malnutrition risk. However, many of those possess practical pitfalls of requiring much time and labor to administer and may not be highly applicable to a Korean population. This study sought to develop and evaluate a Nutrition Risk Screening Tool (NRST) which is simple and quick to administer and widely applicable to Korean hospitalized patients with various diseases. The study was also designed to generate a screening tool predictable of various clinical outcomes and to validate it against the Nutritional Risk Screening 2002 (NRS 2002). Electronic medical records of 424 patients hospitalized at a general hospital in Seoul during a 14-month period were abstracted for anthropometric, medical, biochemical, and clinical outcome variables. The study employed a 4-step process consisting of selecting NRST components, searching a scoring scheme, validating against a reference tool, and confirming clinical outcome predictability. NRST components were selected by stepwise multiple regression analysis of each clinical outcome (i.e., hospitalization period, complication, disease progress, and death) on several readily available patient characteristics. Age and serum levels of albumin, hematocrit (Hct), and total lymphocyte count (TLC) remained in the last model for any of 4 dependent variables were decided as NRST components. Odds ratios of malnutrition risk based on NRS 2002 according to levels of the selected components were utilized to frame a scoring scheme of NRST. A NRST score higher than 3.5 was set as a cut-off score for malnutrition risk based on sensitivity and specificity levels against NRS 2002. Lastly differences in clinical outcomes by patients' NRST results were examined. The results showed that the NRST can significantly predict the in-hospital clinical outcomes. It is concluded that the NRST can be useful to simply and quickly screen patients at high-nutritional risk in relation to prospective clinical outcomes.

A Study on the Abstract Types of the Contemporary Landscape Design (현대조경디자인의 추상유형에 관한 연구)

  • Kim, Jun-Yon;Lee, Haeung-Yul;Bang, Kwang-Ja
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.36 no.6
    • /
    • pp.1-11
    • /
    • 2009
  • This study focuses on Abstract Types in Contemporary Landscape Design. The formation and artistry of contemporary landscape design reveals many areas which Previously have not been able to be expressed in scenic landscape thanks to the deviation of the genre in contemporary landscape and the hybridization that has occurred among architecture, landscape and art genres. The focus of this study is basic research concerning "the abstract", which is used as a creative artistic theory in a variety of art fields such as landscape, architecture and painting. Through a theoretical establishment of "the abstract", its process of change, and the discovery of its contemporary principles, the relationship between each art field in landscapes and the formation of the abstract, abstract language, and abstract properties have been studied. The use of the abstract in contemporary landscape design can be classified in three ways: Inductive abstract representing conceptual transcendental symbols not logically but rather through intuition and transcendental cognition to display the inner expressions, ideas and minds of the artists. Second, a deductive abstract represents an expansive, logical model for the simplification of objects, distortion, exaggeration based on knowledge and logical reasoning about objective fact based on traditional realism. The complexity of the abstract is a concept that is bound to both the deductive & inductive abstract. As a major trend, the concept of "The abstract" in contemporary landscape has been putting forth ever-deeper roots. New trends like abstract works and landscape architecture reflecting the artist's inner expression, in particular, will provide fertile soil for landscape in the future. Further research about the concept of "the abstract" will also be necessary in the time to come.

A Study on the Essence and Tendency of Modern Manager (현대 경영자로서의 본질과 성향 연구)

  • Yeom, Bae-Hoon;Kim, Hyunsoo
    • Journal of Service Research and Studies
    • /
    • v.10 no.3
    • /
    • pp.23-42
    • /
    • 2020
  • This study conceptualized the essence and propensity of modern management in service age, based on philosophy, and developed items to evaluate the conceptualized content. It was carried out as a new study to deepen the study of management philosophy and management theory by the new management framework. In order to establish the philosophical foundation of the modern management, the essence of the modern management was conceptualized based on the fundamental ideas of the East and West, and then an evaluation item was developed to put the essence and propensity of the modern management into practical use through analytical and empirical methods. After analyzing the representative ideas of mankind, it was derived that the Book of Change has the qualification as a philosophical model that can derive the essence of modern management. The Book of Change explains the reasoning of the world in the structure of two opposing parties, such as Taiji or Yin and Yang, and the process of acknowledging the contradictions within each opposing party and overcoming the contradictions through change is the central idea. Because you can see. After conducting a conceptual study, through empirical research, the essence and propensity of a modern manager should be conceptualized. The concept of essence and empirical study of the modern management using the leading role was conducted in two stages. First, a qualitative study using repetitive comparative analysis (CCM), focus group interview (FGI), and text mining was conducted to derive the essential and propensity conceptualization items that modern managers should possess. In addition, a quantitative study using factor analysis to develop sample items and develop measurement items through literature review and FGI was conducted to derive the essential concept of the modern management. Finally, the essence of modern management was derived: learning, preparation, challenge, inclusion, trust, morality, and sacrifice. In the future, it is necessary to conduct empirical research on the effectiveness of the essence of modern management for global and Korean representative companies.

An Experiential Research on a Confucianism Treatment Model - Focusing on an emotion experience program, A Confucianism thinking - (체험적 연구를 통한 덕(德) 철학치유 구조 - 유가의 철학적 사려방법인 「정감체험」 프로그램을 통하여 -)

  • Choi, Yeoung-chan;Choi, Yeon-ja
    • Journal of Korean Philosophical Society
    • /
    • v.126
    • /
    • pp.423-461
    • /
    • 2013
  • The researcher conducted this study to investigate what special meaning does an emotion experience program, a Confucianism philosophical thinking, has for Sunwoo(善友), and based on what structure it unveils a good clue of Sunwoo(善友); and to reveal the structure of philosophical counselling treatment simultaneously. Thus, the researcher performed an "emotion experience program for 3 weeks, targeting 22 research subjects and collected the data of their experience. As for date analysis, a phenomenological analytic method of Colaizzi (1978), one of qualitative research methods was used. It was because the phenomenological analytic method of Colaizzi was suggested to derive common properties of whole research subjects rather than those of individual research subject, which could help develop the theories of philosophical counselling treatment. The finding of the analysis revealed the intrinsic structure of the phenomenon which the research subjects experienced through "an emotion experience program" was reborn as 'unfamiliarity and suspicion', 'burden', 'recognition of a method and a need', 'self-reflection', 'awareness of nature and the correct behavior', 'joy and pleasure', and 'rebirth as a valuable existence'. These were categorized to examine the structure of philosophical counselling treatment. The findings revealed the treatment went through the precesses: 'the start of learning and intentional guidance', 'reflection', 'enlightenment', 'Sugichiin(修己治人)', 'freedom', and 'transcendence. Considering the purpose of Confucian philosophy is living valuable life and the accomplishment of objectives is based on the transcendence, realizing preallotment and putting it into practice, the structure of emotion experience by the research subjects is appropriate for the purpose of Confucian philosophy and the process of objective accomplishment.