• Title/Summary/Keyword: Test hypothesis

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The Behavioral Analysis of the Trading Volumes of Gwangyang Port: Comparison with Incheon and Pyeongtaek-Dangjin Port (광양항의 물동량 행태분석: 인천항, 평택.당진항과 비교)

  • Mo, Soowon
    • Journal of Korea Port Economic Association
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    • v.28 no.3
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    • pp.111-125
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    • 2012
  • This study investigates the behavioral characteristic difference of the container volumes of three ports-Gwangyang, Incheon, and Pyeongtaek-Dangjin. All series span the period January 2003 to December 2011. I first test whether the series are stationary or not. I can reject the null hypothesis of a unit root in each of the level variables and of a unit root for the residuals from the cointegration at the 5 percent significance level. I hitherto make use of error-correction model and find that Gwangyang port is the slowest in adjusting the short-run disequilibrium, whereas the adjustment speed of Incheon is much faster than that of Gwangyang. The impulse response functions indicate that container volumes increase only a little to the negative shocks in exchange rate, while they respond positively to the shocks in the business activity in a great magnitude and decay very slowly to its pre-shock level. meaning that the shocks last very long. The accumulative response to the exchange rate increase of 20 won per dollar and the 5 point industrial production increase is the smallest in Gwangyang, no more than a half of that of two ports. The intervention-ARIMA models also forecast that Gwangyang port will have much lower growth rate than Incheon and Pyeongtaek-Dangjin port in trading volumes.

Enhanced Skin Permeation of a New Capsaicin Derivative (DA-5018) from a Binary Vehicle System Composed of Isopropyl-myristate and Ethoxydiglycol

  • Cha, Bong-Jin;Lee, Eung-Doo;Kim, Won-Bae;Chung, Suk-Jae;Lee, Min-Hwa;Shim, Chang-Koo
    • Archives of Pharmacal Research
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    • v.24 no.3
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    • pp.224-228
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    • 2001
  • DA-5018, a recently synthesized capsaicin analog, appears to possess potent analgesic activity when administered topically. The objective of this study is to test the feasibility of the topical administration of this compound. Specifically, our goal was to identify vehicle system that permit a reasonable transdermal permeation of the compound in mice. Among the vehicles examined, isopropyl myristate (IPM) showed the largest in vitro permeability across the intact skin (83.6 ${\pm}$ 5.42${\mu}$l/$\textrm{cm}^2$/h ). However, due to the limited solubility of DA-5018 in IPM (0.53 mg/ml), the maximal flux from the IPM medium remained at only 44.3 ${\pm}2.87{\mu}$g/$\textrm{cm}^2$/hr. In order to increase the flux, addition of better solvents for DA-5018 was attempted, under the assumption that flux is the result of both solubility and permeability. Ethoxydiglycol (EG) and oleic acid (OA) were selected as examples of food solvents. The addition of IC or OA to IPM at a 1:1 volume ratio resulted in a comparable increase in the solubility of the compound (i.e., to 61.1 and 50.2 mg/ml for EG and OA, respectively). However, the addition of EG at a 1:1 volume ratio, for example, increased the flux 6.3 fold (i.e., $279{\mu}$g/$\textrm{cm}^2$/hr), while OA, at a 1:1 volume ratio, decreased the flux 5 fold (i.e., $9.26{\mu}$g/$\textrm{cm}^2$//hr). The mechanism of this discrepancy between EG and OA was investigated by measuring the permeabilty of DA-5018 across the stratum corneum-removed skin of the mouse, under the hypothesis that the viable skin layer may serve as a barrier for the permeation of lipophilic substances such as DA 5018. The permeability of DA-5018, from the medium of EG or OA, across the viable skin differed greatly for EG ($0.41{\mu}$l/$\textrm{cm}^2$/hr) and OA ($0.086{\mu}$l/$\textrm{cm}^2$/hr), suggesting that a higher permeability across the viable skin layer is needed for the second solvents. The maximum flux across the intact skin was achieved for DA-5018 when EG was added to IPM at a 1:1 volume ratio. Thus, the use of a binary system appears to be the best approach for realizing the transdermal delivery of DA-5018 at a reasonable rate.

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The effect of empathy training game on the children's prosocial behavior (게임을 활용한 공감훈련이 초등학생의 친사회적 행동 증진에 미치는 영향)

  • Kim, Hyung-Hoe
    • The Korean Journal of Elementary Counseling
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    • v.4 no.1
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    • pp.263-284
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    • 2005
  • The purpose of this study was to examine the effect of game-centered empathy training on the prosocial behaviors of elementary schoolers in a bid to suggest how their prosocial behaviors could be boosted. The research questions were posed as below: 1. Does game-based empathy training improve the overall empathy of school children? 2. Does game-based empathy training have a better effect on the cognitive empathy of school children or their emotional empathy? 3. Does game-based empathy training enhance the prosocial behaviors of school children? The subjects in this study were 62 children in their fourth year of D elementary school in Eumseong-gun, north Chungcheong province. They were divided into an experimental group and a control group, and a survey was conducted before and after the experimental group under-went empathy training for about six weeks. The instrument used in this study was David(1980)'s Interpersonal Reactivity Index adopted by Park Sung-hee(1996) to suit school children. Another instrument was Park Sung-hee (1997)'s inventory to assess the prosocial behaviors of children. The collected data were analyzed by SPSS 10.0 for Windows program, and reliability analysis and t-test were employed. The findings of the study were as follows: First, as for the effects of the game-based empathy training on the overall empathy of the elementary school youngsters that included both emotional and cognitive empathy, both groups got lower scores in posttest than in pretest. The experiment produced unexpected results, as the experimental group got significantly lower scores. This fact indicated that the game-based empathy training was ineffective. Second, the game-centered empathy training didn't exercise any influences on their cognitive and emotional empathy. The experiment had a reverse impact on the cognitive and emotional empathy of the experimental group, which implied that the training served as a factor to deteriorate the two types of empathy, and the hypothesis posed in this study was rejected. Therefore, which type of empathy could make a better progress by being exposed to the training couldn't definitely be determined. Third, the game-based empathy training didn't serve to Improve the prosocial behaviors of the elementary schoolers. There was no change in the experimental group, and this fact signified that there's something wrong with the attempt to develop school children's empathy to step up their prosocial behaviors. Based on the above-mentioned findings, the following conclusion was reached: First, the game-centered empathy training had no effects on boosting the overall empathy of the school children. Second, the game-centered empathy training couldn't be said to be effective in improving either cognitive empathy or emotional one. From a viewpoint of relativity, that could be said to affect emotional empathy more than cognitive one. Third, the game-based empathy training wasn't effective in improving prosocial behaviors. Rather, that resulted in interrupting the promotion of prosocial behaviors.

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On the asymptotic correlationship for some process capability indices Ĉp, Ĉpk and Ĉpm under bivariate normal distribution (이변량 정규분포 하에서 공정능력지수에 대한 점근적 상관관계에 관한 연구)

  • Cho, Joong-Jae;Park, Hyo-Il
    • The Korean Journal of Applied Statistics
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    • v.29 no.2
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    • pp.301-308
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    • 2016
  • The process capability index is used to determine whether a production process is capable of producing items within a specified tolerance. Some process capability indices $C_p$, $C_{pk}$ and $C_{pm}$ have been of particular interest as useful management tools for tracking process performance. Most evaluations on process capability indices focus on statistical estimation and test of hypothesis. It is necessary to investigate their asymptotic correlationship among basic estimators ${\hat{C}}_p$, ${\hat{C}}_{pk}$ and ${\hat{C}}_{pm}$ of process capability indices $C_p$, $C_{pk}$ and $C_{pm}$. In this paper, we study their asymptotic correlationship for three process capability indices ${\hat{C}}_p$, ${\hat{C}}_{pk}$ and ${\hat{C}}_{pm}$ under bivariate normal distribution BN(${\mu}_x,{\mu}_y,{\sigma}^2_x,{\sigma}^2_y,{\rho}$). With some nonnormal processes, the asymptotic correlation coefficient of any two respective process capability index estimators could be established.

Statistical Inference for Process Capability Indices and 6 Sigma Qualify Levels (공정능력지수들과 6 시그마 품질수준에 대한 통계적 추론)

  • Cho, Joong-Jae;Sim, Kyu-Young;Park, Byoung-Sun
    • Communications for Statistical Applications and Methods
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    • v.15 no.3
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    • pp.451-464
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    • 2008
  • Six sigma is the rating that signifies "best in clas", with only 3.4 defects per million units or operations. Higher sigma quality level is generally perceived by customers as improved performance by assigning a correspondingly higher satisfaction score. The process capability indices and the sigma level $Z_{st}$ have been widely used in six sigma industries to assess process performance. Most evaluations on process capability indices focus on point estimates, which may result in unreliable assessments of process performance. In this paper, we consider statistical inference for process capability indices $C_p$, $C_{pk}$ and $C_{pm}$. Also, we study better testing procedure on assessing sigma level $Z_{st}$ and capability index $C_{pm}$, for practitioners to use in determining whether a given process is capable. The proposed method is easy to use and the decision making is more reliable. Whether a process is clearly normal or nonnormal, our bootstrap testing procedure could be applied effectively without the complexity of calculation. A numerical result based on our proposed method is illustrated.

Curve Number for a Small Forested Mountainous Catchment (산지 소유역 유출곡선지수)

  • Oh, Kyoung-Doo;Jun, Byong-Ho;Han, Hyung-Geun;Jung, Sung-Won;Cho, Young-Ho;Park, Soo-Yun
    • Journal of Korea Water Resources Association
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    • v.38 no.8 s.157
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    • pp.605-616
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    • 2005
  • In this paper, runoff curve numbers (CN's) for a small forested mountainous catchment are estimated using rainfall-runoff data measured at Sulma experimental catchment every 10 minutes and a new guideline for applying the antecedent rainfall conditions (ARC's) for small mountainous watersheds in Korea is proposed. Sulma experimental catchment is a typical natural mountainous basin with $97\%$ of forested land cover and CN's are estimated to be in the range between 51 and 89 with median value of 72. The test hypothesis stating as 1-day ARC is better than 5-day ARC in determining CN's for a small mountainous watershed is shown to be acceptable. Also, linear regression equations for the estimation of CN's for small mountainous catchments are proposed. As there is no significant investigations available on CN's for small mountainous catchments, the newly proposed relationships between CN's and ARC may be used as a preliminary guideline to assign CN's for the estimation of floods from rainfall data on mountainous regions.

Supply of Tryptophan and Tryptamine Influenced the Formation of Melatonin in Viola Plants (제비꽃속(Viola) 식물에서 tryptophan과 tryptamine 공급이 멜라토닌 생성에 미치는 영향)

  • Kim, Yeo-Jae;Yoon, Young-Ha;Park, Woong-June
    • Journal of Life Science
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    • v.21 no.2
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    • pp.328-333
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    • 2011
  • Melatonin has been known as an animal hormone. However, melatonin exists in diverse organisms including higher plants. The biosynthesis and physiological roles for melatonin in plants is still largely unknown, although both dicot and monocot plants have melatonin and some medicinal plants even contain large amounts of melatonin. In this study we detected melatonin in diverse Viola plants, in which melatonin had not been examined so far, by reverse phase HPLC analysis, demonstrating the wide existence of melatonin in the genus of Viola. We then fed tryptophan (Trp) and tryptamine (TAM) to the incubation medium for Viola leaf sections to test their effects on melatonin formation. Trp is also the hypothesized starting material of melatonin in plants, and TAM is the following intermediate produced by the decarboxylation of Trp. Trp feeding did not affect the contents of melatonin. In contrast, TAM feeding clearly increased the level of melatonin in Viola leaves. Because TAM is derived from Trp, we concluded that the Trp-TAM pathway exists in Viola plants as well. Ineffectiveness of Trp feeding to the change of melatonin contents supports the hypothesis that the decarboxylation step from Trp to TAM is the rate-limiting step in plant melatonin biosynthesis.

Influence of New Town Residents' Housing Value of an Apartment House on Housing Satisfaction and Customer Loyalty -With focus on the 2nd term new town case- (신도시 거주자의 아파트에 대한 주거가치가 주거만족과 고객충성도에 미치는 영향 -2기 신도시 사례를 중심으로-)

  • Lee, Mu-Seon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.10
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    • pp.412-425
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    • 2016
  • Recently, the influence of the residential value of new town apartment houses has been increasing in the housing market; however, there has been little study on the relationship between the housing value and customer loyalty. This study analyzed the influence of the housing value on housing satisfaction and customer loyalty. To this end, this study conducted a survey targeting 519 residents in the second term new town. Accordingly, basic statistics, reliability and hypothesis test were carried out using SPSS 21.0 and ANOVA as an analysis method. The study results are as follows. First, as a result of factor analysis of the housing value, the factor was analyzed as 6 sorts, such as safety, sociality, convenience, economic feasibility, aesthetics, and comfort. Second, safety, comfort, and convenience among the factors in the housing value were found to have a significant influence on the housing satisfaction. This means that the concepts of property and assets reflect the development of new urban city apartments. Third, a new town house purchaser's positive housing value and housing satisfaction were found to increase customer loyalty. This greater satisfaction of the current residential apartment dwellers means that they are more likely to introduce their relatives and neighbors. These results suggest that a positive outlook of a new town householder on the housing value and housing satisfaction will eventually work more on revitalizing the housing market.

The Effects of Consumption Value on Satisfaction and Loyalty: Focusing on Chinese Smartphone Users (소비가치가 만족과 충성도에 미치는 영향: 중국 스마트폰 이용고객을 중심으로)

  • Cho, Hyun-Jin
    • Journal of Distribution Science
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    • v.12 no.8
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    • pp.123-132
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    • 2014
  • Purpose - Recently, Korean companies have been struggling to perform well in the larger smartphone market in China, which is regarded as a blue ocean area. First, it is very important to accurately understand the Chinese consumers, who have a different consumption culture and value system from the Korean culture and system. This would help to identify priorities for the Chinese market. Further, considering the smartphone industry, where technological change is rapid, Korean companies will need to take prompt measures about market trends in order to establish strong competitiveness. Consequently, this study focused on analyzing the relationship between the variables of consumption value, satisfaction, and loyalty in the Chinese smartphone market. The principal dimensions of consumption value, which smartphones have, was analyzed, and the influence on satisfaction was identified. Moreover, the relationship among the variables of satisfaction, attitudinal loyalty, and behavioral loyalty was empirically analyzed. Research design, data, and methodology - This study examined the relationships between various consumption values (functional value, emotional value, social value, epistemic value, and economic value), along with satisfaction and loyalty. The data were collected through a questionnaire survey that was circulated to 310 customers who were users of smartphones in Chingdao and Yeontae regions in China. The survey was conducted from June 23 to August 4, 2013. A total of 301 responses to the questionnaires were collected and used for the data analysis. Moreover, a path analysis based on Lisrel 8.54 was used for the hypothesis test. Results - The variables of functional value, emotional value, social value, and epistemic value were revealed to have positive effects on satisfaction related to smartphone usage. However, the variables of monetary cost and psychological cost were not found to have negative effects on satisfaction related to smartphone usage. Moreover, satisfaction positively influenced attitudinal loyalty related to smartphone usage, but did not have a significant influence on behavioral loyalty related to smartphone usage. Specifically, satisfaction is essential, but not a sufficient condition for building behavioral loyalty in relation to smartphone usage. In addition, attitudinal loyalty positively influenced behavioral loyalty in relation to smartphone usage. Conclusions - First, this study shows that functional value, emotional value, social value, and epistemic value in relation to smartphone usage are important for marketing in the Chinese smartphone market. Particularly, functional value and emotional value play pre-eminent roles as regards customer loyalty in the use of smartphones. Second, the results of this study reveal that the variables of monetary cost and psychological cost are not important to the Chinese consumers. Specifically, the smartphone price and cognitive effort are not perceived as value barriers. Third, satisfaction did not guarantee behavioral loyalty in relation to smartphone usage, and the strategic approach for improving the repurchase and referral action in relation to smartphones based on solid attitudinal loyalty would be desirable and should be the focus of the marketing activities of Korean smartphone companies.

The Effect of Corporate Social Responsibility Activities on Brand Equity and Consumer Attitude (사회적 책임활동이 브랜드자산과 소비자태도에 미치는 영향 연구)

  • Park, Nam-Goo;Choi, Ho-Gyu
    • Journal of Distribution Science
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    • v.12 no.8
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    • pp.17-29
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    • 2014
  • Purpose - The use of corporate social activities to implement the concept of corporate social responsibility enhances brand equity and attitude, and strengthens economic competitiveness. In areas such as mobile communications, companies take the responsibility of protecting customers and enhance the quality of the mobile communication service, helping to make an effort to obey the regulations of the public trade order and fair trade agreement, enabling a healthy society through communication with elderly living alone or youths without parents, and enhancing marketing strategies. Research design, data, and methodology - To test the hypothesis, a survey was conducted. The surveyed population includes people who use the big three mobile communication services. The survey was conducted from October 4th to October 14th, 2013. A total of 500 survey questionnaires were circulated and 483 were collected; out of these, 32 were excluded due to missing or incomprehensible information. The data was analyzed with SPSS 18.0 via frequency analysis, trust analysis, search factor analysis, relationship analysis, confirmation factor analysis using AMOS 18.0, and structural equation model analysis. Results - Research on corporate social responsibility has been frequently conducted recently. Companies are perceived as social constituents satisfying the social desires of people in addition to customer needs. Further, companies are returning profits to society to satisfy community needs, because there is greater emphasis on the social responsibilities of companies. Companies' social responsibilities should include marketing strategies and the identification of customer needs. This study shows that social service activities influence brand value, which influences customer attitudes; therefore, social service activities indirectly influence customer attitudes. In order to increase customers' purchasing intention, it is essential to improve brand image via social services and provide a distinctive quality of service. Conclusions - This research has used the purposive selection method in the empirical analysis to identify the effect of social services on brand value and customer attitude. Therefore, this study revealed that businesses, whose ultimate objective is to improve customers' purchasing intention, should promote their brand equity through corporate social responsibility activities and offer a distinct service quality. Limitations in the progress of research were found and future indications to overcome these limitations are suggested as follows. First, survey responders had a limited understanding of social responsibilities; therefore, this concept needs to be explained to people first. Second, the research was done on people who live in Daejeon; thus, it is not representative of the entire country. The research has to be repeated with people in other cities. Third, there is a limitation in the study because the purposive selection method was used on Daejeon customers. In the future, a more precise selection of the population is needed. Fourth, Daejeon has unique geographical and size characteristics. Thus, customers in Seoul and other areas may display different characteristics and research on them may reveal different findings. Therefore, again, this study has to be repeated in other areas.