• Title/Summary/Keyword: interaction quality

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Mechanical and Operational Factors Affecting the Efficiency of Rice Polishing Machines (정미기의 능률에 미치는 기계적 요인및 작동조건에 관한 연구)

  • 노상하;최재갑
    • Journal of Biosystems Engineering
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    • v.1 no.1
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    • pp.17-48
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    • 1976
  • In analyzing the operational characteristics of a rice whitening machine, the internal radial pressure of the machine was measured using strain gage equipment. Changes in cylinder and feed screw configurations, screen type, cylinder speed and counter-pressure levels were examined to determine their impact on the quality and quantity of milled rice and the performance of the machine. The results are summarized as follows: 1. The internal radial pressure in the whitening chamber varied with the surface condition of the grain being processed. During the first or second pass through the machine, pressure was relatively low, reached a maximum after two to three passes with combinations I and II, three to six with combination III and then began to fall. 2. The pitch of the feed screw and the size of the feed gate opening which determine the rate of entry of grain into the whitening chamber, appeared to be the most important factor aff-::cting the degree of radial pressure, quality and quantity of milled rice and the efficiency of the machine. Using a feed screw with a wide pitch (4.8cm), radial pressure was relatively high and head rice recovery ratio \vere quite low. In this case capacity and machine effic\ulcorneriency were much higher than obtained when using a feed screw with a narrow pitch (2.3cm). Very significant responses in radial pressure, head rice recovery rates and machine capacity were observed with changes in cylinder speed and counter-pressure levels when using the wide pitch feed screw. 3. The characteristics of the screen which surrounds the whitening chamber had an important effect on whitening efficiency. The existence of small protuberances on the original screen resulted in significant increases in both machine capacity and efficiency but without a significant decrease in head rice recovery or development of excessive radial pressure. Further work is required to determine the effects of screen surface conditions and the shape of the cylinderical steel roller on the rate of bran removal, machine efficiency and recovery rates. The size of the slotted perforations 0:1 the screen affects total milled rice recovery. The opening size on the original screen was fabricated to accommodate the round shape of Japonica rice varieties but was not suitable for the more slender Indica type. Milling Indica varieties with this screen resulted in a reduction in total milled rice recovery. 4. An increase in cylinder speed from 380 to 820 rpm produced a positive effect on head rice recovery for all machine combinations at every level of counter-pressure used in the tests. Head rice recovery was considerably lower at 380rpm using a wide screw pitch when compared to the results obtained at speeds from 600 to 820 r.p.m. The effects of cylinder speed On radial pressure, capacity and machine efficiency showed contrasting results, depending on the width of the feed screw pitch. With a narrow feed screw pitch (2.3cm), a direct proportional relationship was observed bet\ulcornerween cylinder speed and both radial pressure and machine efficiency. In contrast, using a 4.8 centimeter pitch feed roller produced a series of inverse relationships between the above variables. Based on the results of this study it is recommended when milling Indica type long grain rice varieties that the cylinder speed of the original machine be increased from 500-600 rmp up to a minimum of 800 rpm to obtain a greater abrasive effect between the grain and the screen. The pitch of the feed screw should be also reduced to decr\ulcornerease the level of internal radial pressure and to obtain higher machine efficiency and increased quality of milled rice with increased cylinder speeds. Further study on the interaction between cylinder speed and feed screw pitch is recommended. 5. An increase in the counter pressure level produced a negative effect On the head rice recovery with an increase in radial pressure, capacity, and machine efficiency over all combinations and at every level of cylinder speed. 6. Head rice recovery rates were conditioned primarily by the pressure inside the whitening chamber. According to the empirical cha racteristics curve developed in this study, the relationships of head rice recovery ($Y_h$) and machine capacity ($Y_c$/TEX>) to internal radial pressure ($X_p$) followed an inverse quadratic function and a linear function respectively: $$Y_h^\Delta=\frac{1}{{1.4383-0.2951X_p^\ast+0.1425X_p^{\ast\ast}}^2} , (R^2=0.98)$$ $$Y_c^\Delta=-305.83+374.37X_p^{\ast\ast}, (R^2=0.88)$$ The correlation between capacity and power consumption per unit of brown rice expressed in the following exponential function: $$Y_c^\Delta=1.63Y_c^{-0.7786^\{\ast\ast}, (R^2=0.94)$$ These relationships indicate that when radial pressure increases above a certain range (1. 6 to 2.0 kg/$cm^2$ based On the results of the experiment) head ricerecovery decrea\ulcornerses in a quadratic relation with a inear increase in capacity but without any decrease in power consump tion per unit of brown rice. On the other hand, if radial pressure is below the range shown above, power consumption increases dramatically with a lin\ulcornerear decrease in capacity but without significant increases in head rice recovery. During the operation of a given whitening machine, the optimum radial pressure range or the correct capacity range should be selected by controlling the feed rate and/or counter-pressure keeping in mind the condition of the grain, particulary the hardness. It was observed that the total number of passes is related to radial pessure level, feed rate and counter-pressure level. The higher theradial pressure the fewer num\ulcornerber of pass required but with decreased head rice recovery. In particular, when using high feed rates, the total number of passes should be increased to more than three by reducing the counter-pressure level to avoid decreaseases in head rice recovery (less than 65 percent head rice recovery on the basis of brown rice) at every cylinder speed. 7. A rapid rise in grain temperature seemed to have a close relationship with the pressure generated inside the whitening chamber and, subsequently with head rice reco\ulcornervery rates. The higher the rate of increase, the lower were the resulting head rice recoveries.

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Geochemical Equilibria and Kinetics of the Formation of Brown-Colored Suspended/Precipitated Matter in Groundwater: Suggestion to Proper Pumping and Turbidity Treatment Methods (지하수내 갈색 부유/침전 물질의 생성 반응에 관한 평형 및 반응속도론적 연구: 적정 양수 기법 및 탁도 제거 방안에 대한 제안)

  • 채기탁;윤성택;염승준;김남진;민중혁
    • Journal of the Korean Society of Groundwater Environment
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    • v.7 no.3
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    • pp.103-115
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    • 2000
  • The formation of brown-colored precipitates is one of the serious problems frequently encountered in the development and supply of groundwater in Korea, because by it the water exceeds the drinking water standard in terms of color. taste. turbidity and dissolved iron concentration and of often results in scaling problem within the water supplying system. In groundwaters from the Pajoo area, brown precipitates are typically formed in a few hours after pumping-out. In this paper we examine the process of the brown precipitates' formation using the equilibrium thermodynamic and kinetic approaches, in order to understand the origin and geochemical pathway of the generation of turbidity in groundwater. The results of this study are used to suggest not only the proper pumping technique to minimize the formation of precipitates but also the optimal design of water treatment methods to improve the water quality. The bed-rock groundwater in the Pajoo area belongs to the Ca-$HCO_3$type that was evolved through water/rock (gneiss) interaction. Based on SEM-EDS and XRD analyses, the precipitates are identified as an amorphous, Fe-bearing oxides or hydroxides. By the use of multi-step filtration with pore sizes of 6, 4, 1, 0.45 and 0.2 $\mu\textrm{m}$, the precipitates mostly fall in the colloidal size (1 to 0.45 $\mu\textrm{m}$) but are concentrated (about 81%) in the range of 1 to 6 $\mu\textrm{m}$in teams of mass (weight) distribution. Large amounts of dissolved iron were possibly originated from dissolution of clinochlore in cataclasite which contains high amounts of Fe (up to 3 wt.%). The calculation of saturation index (using a computer code PHREEQC), as well as the examination of pH-Eh stability relations, also indicate that the final precipitates are Fe-oxy-hydroxide that is formed by the change of water chemistry (mainly, oxidation) due to the exposure to oxygen during the pumping-out of Fe(II)-bearing, reduced groundwater. After pumping-out, the groundwater shows the progressive decreases of pH, DO and alkalinity with elapsed time. However, turbidity increases and then decreases with time. The decrease of dissolved Fe concentration as a function of elapsed time after pumping-out is expressed as a regression equation Fe(II)=10.l exp(-0.0009t). The oxidation reaction due to the influx of free oxygen during the pumping and storage of groundwater results in the formation of brown precipitates, which is dependent on time, $Po_2$and pH. In order to obtain drinkable water quality, therefore, the precipitates should be removed by filtering after the stepwise storage and aeration in tanks with sufficient volume for sufficient time. Particle size distribution data also suggest that step-wise filtration would be cost-effective. To minimize the scaling within wells, the continued (if possible) pumping within the optimum pumping rate is recommended because this technique will be most effective for minimizing the mixing between deep Fe(II)-rich water and shallow $O_2$-rich water. The simultaneous pumping of shallow $O_2$-rich water in different wells is also recommended.

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Environmental Geochemistry and Contamination Assessment of the Tohyun Mine Creek, Korea (토현광산 수계의 환경지구화학적 특성과 오염도 평가)

  • 이찬희;이현구;이종창;전서령
    • Economic and Environmental Geology
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    • v.34 no.5
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    • pp.471-483
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    • 2001
  • The pH values of the mine and surface water from the Tohyun mine creek were higher compared with those of groundwater, and 2nd round samples in same sites were even alkaline. The stream and mine waters belong to the characteristics of (Ca+Mg)-(SO$_4$) and (Ca+Mg)-(HCO$_3$) types, and groundwaters have to the (Ca+Mg+Na+K)-(HCO$_3$+SO$_4$) type. As the 2nd samples. concentrations of mostly anions are increasing compared with the forder samples. However, the mostly cation concentrations are decreasing. The hydrogeochemistry indicate that water quality is different chemical characteristics and evolution trends. The range of $\delta$D and $\delta$$^{18}$ valutes (relative to SMOW) in the waters are shown in -62.2 to -70.1$\textperthousand$, and -8.1 to -9.4$\textperthousand$. The values are plowed parallel to $\delta$D=8$\delta$$^{18}$ O+ (6$\pm$4). The d values of groundwater show 2.4, which is lower than the surface (5.2) and mine (7.6) waters. Strontium concentra titans range from 0.025 to 11.844 mg/$\ell$ in all kinds of water samples, but the groundwater has the highest contents The $^{87}$ Sr/$^{86}$ Sr ratios (0.7115 to 0.7129) show more lightened to the groundwater. The $\delta$$^{18}$ O value, Ca and Sr contents are decreased with $^{87}$ Sr/$^{86}$ Sr increasing, because it is support to the altitude effects of the sampling sites rather than a water-rock interaction of environmental isotope. Using computer code of WATEQ4F, saturation indices of albite, Quartz, gibssite and gypsum are calculated to be soluble. The calcite and dolomite show super saturation state, however, clay mineral species are plotted boundary between undersaturation and supersaturation. In the Tohyun mine creek, reaction materials with ore wastes arid precipitation have influence upon increasing EC and TDS of the waters independent of pH. The SO$_4$ concentrations in the mine water is 181.845 mg/$\ell$. This is abruptly increase in surface water and then detected 249.727 mg/$\ell$ in the groundwater. As a results of the calculated sulfate mineral solubilities, the sulfate ions became saturation states an above 150 mg/$\ell$ concentrations.

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Mitigation Effect of Drought Stress by Plant Growth-promoting Bacterium Bacillus sp. SB19 on Kale Seedlings in Greenhouse (식물생장촉진 Bacillus sp. SB19 균주의 케일 처리에 대한 가뭄 스트레스 완화 효과)

  • Kim, Dayeon;Lee, Sang-Yeob;Kim, Jung-Jun;Han, Ji-Hee
    • Korean Journal of Organic Agriculture
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    • v.24 no.4
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    • pp.833-847
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    • 2016
  • Drought stress is a major agricultural limitation to crop productivity worldwide, especially by which leafy vegetables, plant leaves eaten as vegetable, could be more lethal. The study was carried out to know the effect of drought tolerance plant growth promoting bacteria (PGPB) on water stress of kale seedlings. A total of 146 morphologically distinct bacterial colonies were isolated from bulk soil and rhizosphere soil of leafy vegetables and screened for plant growth promoting microbioassay in greenhouse. Out of them the isolate SB19 significantly promoted the growth of kale seedlings in increasement of about 42% of plant height (14.1 cm), 148% of leaf area ($19.0cm^2$) and 138% of shoot fresh weight (1662.5 mg) attained by the bacterially treated plants compared to distilled water treated control (9.9 cm, $7.7cm^2$, 698.8 mg). Shoot water content of SB19 treated kale seedlings (1393.8 mg) was also increased about 152% compared with control (552.5 mg). The SB19 isolated from bulk soil of kale plant in Iksan, Korea, was identified as species of Bacillus based on 16S rRNA gene sequencing analysis. We evaluated the effect of drought tolerance by the Bacillus sp. SB19 on kale seedlings at 7th and 14th days following the onset of the water stress and watering was only at 7th day in the middle of test. In the survey of 7th and 14th day, there were mitigation effect of drought stress in kale seedlings treated with $10^6$ and $10^7cell\;mL^{-1}$ of SB19 compared to distilled water treated control. Especially, there were more effective mitigation of drought damage in kale seedlings treated with $10^7cell\;mL^{-1}$ than $10^6cell\;mL^{-1}$. Further, although drought injury of bacterially treated kale seedlings were not improved at 14th day compared with 7th day, drought injury of $10^7cell\;mL^{-1}$ of SB19 treated kale seedlings were not happen rapidly but developed over a longer period of time than $10^6cell\;mL^{-1}$ of SB19 or control. The diffidence of results might be caused by the concentration of bacterial suspension. This study suggests that beneficial plant-microbe interaction could be a important role of enhancement of water availability and also provide a good method for improving quality of leafy vegetables under water stress conditions.

A Pilot Study of Evaluating the Reliability and Validity of Pattern Identification Tool for Insomnia and Analyzing Correlation with Psychological Tests (불면증 변증도구 신뢰도와 타당도 평가 및 심리검사와의 상관성에 대한 초기연구)

  • Jeong, Jin-Hyung;Lee, Ji-Yoon;Kim, Ju-Yeon;Kim, Si-Yeon;Kang, Wee-Chang;Lim, Jung Hwa;Kim, Bo Kyung;Jung, In Chul
    • Journal of Oriental Neuropsychiatry
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    • v.31 no.1
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    • pp.1-12
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    • 2020
  • Objectives: The purpose of this study was to evaluate the reliability and validity of the instrument on pattern identification for insomnia (PIT-Insomnia) and verify the correlation between PIT-Insomnia and psychological tests. Methods: Two evaluators examined the pattern identification of the participants who met insomnia disorder diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorder, Fifth Edition (DSM-5) and took the Insomnia Severity Index (ISI) score over 15 once manually and twice using the PIT-Insomnia to measure the inter-rater and test-retest reliability. We also conducted the following surveys: the Pittsburgh Sleep Quality Index (PSQI), the Korean version of Beck's depression inventory (K-BDI), the Korean version of the State-Trait Anxiety Inventory (STAI-K), the Korean Symptom checklist-95 (KSCL-95), and the EuroQol-5 dimension (EQ-5D), to measure concurrent validity and correlation between the PTI-Insomnia and psychological tests. Results: 1. The test-retest reliability analysis of the pattern identification results showed moderate agreement, and test-retest reliability analysis of each pattern identification score showed agreements from poor to moderate. 2. The inter-rater reliability analysis of the pattern identification results via manual showed slight agreement, when analysis was performed with calibration, the inter-rater reliability analysis of the pattern identification results via manual showed fair agreement. 3. The concordance analysis between results via manual and the PIT-Insomnia showed poor agreement, when the analysis was performed with calibration, concordance analysis showed fair agreement. 4. The concordance analysis between the PIT-Insomnia and the PSQI showed positive linear correlation. 5. The concordance analysis between the PIT-Insomnia and the PSQI, K-BDI, STAI-K, KSCL-95, and EQ-5D showed that non-interaction between the heart and kidney have positive linear correlation with the K-BDI, anxiety item of KSCL-95, dual deficiency of the heart-spleen have positive linear correlation with somatization item of KSCL-95, paranoia item of KSCL-95, heart deficiency with timidity have positive linear correlation with stress vulnerability item of KSCL-95, parania item of KSCL-95, phlegm-fire harassing the heart have positive linear correlation with K-BDI, paranoia item of KSCL-95, depressed liver qi transforming into fire have positive linear correlation with the anxiety item of KSCL-95, parania item of KSCL-95, all pattern identification have negative linear correlation with EQ-5D. Conclusions: The PIT-Insomnia has moderate agreement of reliability and reflects the severity of insomnia since it has some concurrent validity with the PSQI. There are some correlations between the PTI-Insomnia with specific psychological tests, so we could suggest it can be used appropriately in the clinical situation.

Social Network Analysis for the Effective Adoption of Recommender Systems (추천시스템의 효과적 도입을 위한 소셜네트워크 분석)

  • Park, Jong-Hak;Cho, Yoon-Ho
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.305-316
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    • 2011
  • Recommender system is the system which, by using automated information filtering technology, recommends products or services to the customers who are likely to be interested in. Those systems are widely used in many different Web retailers such as Amazon.com, Netfix.com, and CDNow.com. Various recommender systems have been developed. Among them, Collaborative Filtering (CF) has been known as the most successful and commonly used approach. CF identifies customers whose tastes are similar to those of a given customer, and recommends items those customers have liked in the past. Numerous CF algorithms have been developed to increase the performance of recommender systems. However, the relative performances of CF algorithms are known to be domain and data dependent. It is very time-consuming and expensive to implement and launce a CF recommender system, and also the system unsuited for the given domain provides customers with poor quality recommendations that make them easily annoyed. Therefore, predicting in advance whether the performance of CF recommender system is acceptable or not is practically important and needed. In this study, we propose a decision making guideline which helps decide whether CF is adoptable for a given application with certain transaction data characteristics. Several previous studies reported that sparsity, gray sheep, cold-start, coverage, and serendipity could affect the performance of CF, but the theoretical and empirical justification of such factors is lacking. Recently there are many studies paying attention to Social Network Analysis (SNA) as a method to analyze social relationships among people. SNA is a method to measure and visualize the linkage structure and status focusing on interaction among objects within communication group. CF analyzes the similarity among previous ratings or purchases of each customer, finds the relationships among the customers who have similarities, and then uses the relationships for recommendations. Thus CF can be modeled as a social network in which customers are nodes and purchase relationships between customers are links. Under the assumption that SNA could facilitate an exploration of the topological properties of the network structure that are implicit in transaction data for CF recommendations, we focus on density, clustering coefficient, and centralization which are ones of the most commonly used measures to capture topological properties of the social network structure. While network density, expressed as a proportion of the maximum possible number of links, captures the density of the whole network, the clustering coefficient captures the degree to which the overall network contains localized pockets of dense connectivity. Centralization reflects the extent to which connections are concentrated in a small number of nodes rather than distributed equally among all nodes. We explore how these SNA measures affect the performance of CF performance and how they interact to each other. Our experiments used sales transaction data from H department store, one of the well?known department stores in Korea. Total 396 data set were sampled to construct various types of social networks. The dependant variable measuring process consists of three steps; analysis of customer similarities, construction of a social network, and analysis of social network patterns. We used UCINET 6.0 for SNA. The experiments conducted the 3-way ANOVA which employs three SNA measures as dependant variables, and the recommendation accuracy measured by F1-measure as an independent variable. The experiments report that 1) each of three SNA measures affects the recommendation accuracy, 2) the density's effect to the performance overrides those of clustering coefficient and centralization (i.e., CF adoption is not a good decision if the density is low), and 3) however though the density is low, the performance of CF is comparatively good when the clustering coefficient is low. We expect that these experiment results help firms decide whether CF recommender system is adoptable for their business domain with certain transaction data characteristics.

It Doesn't Taste the same from Someone Else's Plate: The Influence of Culture in Interpersonal Retail Service Evaluations (별인적반자적미도불일양(别人的盘子的味道不一样): 문화대인제령수복무평개적영향(文化对人际零售服务评价的影响))

  • Spielmann, Nathalie;Kim, Ju-Ran
    • Journal of Global Scholars of Marketing Science
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    • v.20 no.2
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    • pp.164-172
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    • 2010
  • This study reviews the influence of culture in interpersonal servicescapes by examining the restaurant retail setting. Two cultures (Canada and France) are surveyed in order to better understand their retail expectations towards interpersonal servicescapes. Using Hofstede's (1991) cultural dimensions to explain some of the differences between Canadian and French restaurant patrons, this study demonstrates a potentially interesting research avenue in the field of cross-cultural interpersonal services marketing. It demonstrates that cultural dimensions do not operate independently but interdependently. Understanding this can help retailers better explain complex service interactions between countries that may appear similar in terms of various socio-demographic features. In this exploratory research, a measure via exploratory factor analysis was developed, one that encompasses both the physical and service aspects common to interpersonal servicescape by using personality traits. This measure was tested in order to better understand the service expectations between two cultures, Canada and France. Five dimensional structures were uncovered in both cultures but with different traits and groupings. The differences between the traits uncovered and the overall Canadian and French personality structures find some explanation using Hofstede's (1991) cultural dimensions. The results of this survey point to a possible explanation as to why when services are transferred between cultures, the perceptions of them can be different and sometimes even lead to service failure. There are clearly some cultural differences between the Canadian and French consumers and their overall expectations regarding their consumption experience. Reviewing the first factor of the French and Canadian personality structures shows that the individualist/collectivist differences are apparent between the Canadian and the French cultures. The second dimension also has quite a few traits in common, five, all of which have the personal treatment aspect of the restaurant experience that a service provider would be responsible for: polite, respectful, and dedicated. Notable is that the French dimension does not include the authenticity or the hospitable aspect of the experience but includes even more features that are inherent to the personal interaction, such as charming and courteous. The third dimension of the Canadian and French structures reflects completely different expectations. Whereas the French dimension centers around energy and enthusiasm, the Canadian version is more laid-back and relaxed. There is extroversion in the French dimension to introversion in the Canadian dimension. This could be explained by differences on the Uncertainty Avoidance dimension as outlined by Hofstede (1991). The fourth dimension seems to confirm previously outlined cultural differences. Whereas Canadians, being a bit lower on uncertainty avoidance and power distance, prefer an intimate and private experience, the French continue to expect extraversion and inclusive features to their experience. The fifth dimension is in the French personality structure a clear expression of the high power distance society, where the roles of the players in the restaurant experience are clearly defined and the rules of engagement preserved. This study demonstrates that different cultures clearly do relate to different expectations regarding interpersonal services. This is apparent in the dimensions that come up in both the French and the Canadian personality structures, not only in terms of how different they are but also in with which cultural dimensions these can be explained. For interpersonal servicescapes, the use of personality traits is interesting as it allows for both physical and service features to be accounted for. Furthermore, the social component inherent to interpersonal servicescapes surfaces in most of the dimensions of the service personality structures. The quality of social exchanges is extremely important, and this even more so in cross-cultural situations, where the expec tations regarding the service experience may vary. As demonstrated by this research and using Hofstede's (1991) paradigm, not all societies will have the same expectations pertaining to the interpersonal services. Furthermore, the traditions surrounding the type of service can also have an impact on the service evaluations and differ between countries and cultures. However, using personality traits may also allow for retailers to see which service traits are common to two or more cultures where they seek to be present, and focus on these in the offering. The findings demonstrate the importance of the individualist and collectivist dimension for interpersonal servicescapes. This difference between the French and the Canadian personality structure is apparent in the most dominant dimension as well as within others. The findings are a step in explaining how retailers can transfer and then measure interpersonal services across cultures.

The Verification of Computer Simulation of Nitinol Wire Stent Using Finite Element Analysis (유한요소법을 이용한 나이티놀 와이어 스텐트의 전산모사 실험 데이터 검증)

  • Kim, Jin-Young;Jung, Won-Gyun;Jeon, Dong-Min;Shin, Il-Gyun;Kim, Han-Ki;Shin, Dong-Oh;Kim, Sang-Ho;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.20 no.3
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    • pp.139-144
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    • 2009
  • Recently, the mathematical analysis of stent simulation has been improved, with the help of development of various tool which measure mechanical property and location of stent in artery. The most crucial part of the stent modeling is how to design ideal stent and to evaluate the interaction between stent and artery. While there has been great deal of researches on the evaluation of the expansion, stress distribution, deformation of the stent in terms of the various parameters, few verification through computer simulation has been performed about deformation and stress distribution of the stent. In this study, we have produced the corresponding results between experimental test using Universal Testing Machine and computer simulation for the ideal model of stent. Also, we have analyzed and compared stress distribution of stent in the cases of that with membrane and that without membrane. The results of this study would provide minimum change of plan and good quality for ideal stent replacing damaged artery through the analysis using computer simulation in the early stage of stent design.

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An Empirical Study on How the Moderating Effects of Individual Cultural Characteristics towards a Specific Target Affects User Experience: Based on the Survey Results of Four Types of Digital Device Users in the US, Germany, and Russia (특정 대상에 대한 개인 수준의 문화적 성향이 사용자 경험에 미치는 조절효과에 대한 실증적 연구: 미국, 독일, 러시아의 4개 디지털 기기 사용자를 대상으로)

  • Lee, In-Seong;Choi, Gi-Woong;Kim, So-Lyung;Lee, Ki-Ho;Kim, Jin-Woo
    • Asia pacific journal of information systems
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    • v.19 no.1
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    • pp.113-145
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    • 2009
  • Recently, due to the globalization of the IT(Information Technology) market, devices and systems designed in one country are used in other countries as well. This phenomenon is becoming the key factor for increased interest on cross-cultural, or cross-national, research within the IT area. However, as the IT market is becoming bigger and more globalized, a great number of IT practitioners are having difficulty in designing and developing devices or systems which can provide optimal experience. This is because not only tangible factors such as language and a country's economic or industrial power affect the user experience of a certain device or system but also invisible and intangible factors as well. Among such invisible and intangible factors, the cultural characteristics of users from different countries may affect the user experience of certain devices or systems because cultural characteristics affect how they understand and interpret the devices or systems. In other words, when users evaluate the quality of overall user experience, the cultural characteristics of each user act as a perceptual lens that leads the user to focus on a certain elements of experience. Therefore, there is a need within the IT field to consider cultural characteristics when designing or developing certain devices or systems and plan a strategy for localization. In such an environment, existing IS studies identify the culture with the country, emphasize the importance of culture in a national level perspective, and hypothesize that users within the same country have same cultural characteristics. Under such assumptions, these studies focus on the moderating effects of cultural characteristics on a national level within a certain theoretical framework. This has already been suggested by cross-cultural studies conducted by scholars such as Hofstede(1980) in providing numerical research results and measurement items for cultural characteristics and using such results or items as they increase the efficiency of studies. However, such national level culture has its limitations in forecasting and explaining individual-level behaviors such as voluntary device or system usage. This is because individual cultural characteristics are the outcome of not only the national culture but also the culture of a race, company, local area, family, and other groups that are formulated through interaction within the group. Therefore, national or nationally dominant cultural characteristics may have its limitations in forecasting and explaining the cultural characteristics of an individual. Moreover, past studies in psychology suggest a possibility that there exist different cultural characteristics within a single individual depending on the subject being measured or its context. For example, in relation to individual vs. collective characteristics, which is one of the major cultural characteristics, an individual may show collectivistic characteristics when he or she is with family or friends but show individualistic characteristics in his or her workplace. Therefore, this study acknowledged such limitations of past studies and conducted a research within the framework of 'theoretically integrated model of user satisfaction and emotional attachment', which was developed through a former study, on how the effects of different experience elements on emotional attachment or user satisfaction are differentiated depending on the individual cultural characteristics related to a system or device usage. In order to do this, this study hypothesized the moderating effects of four cultural dimensions (uncertainty avoidance, individualism vs, collectivism, masculinity vs. femininity, and power distance) as suggested by Hofstede(1980) within the theoretically integrated model of emotional attachment and user satisfaction. Statistical tests were then implemented on these moderating effects through conducting surveys with users of four digital devices (mobile phone, MP3 player, LCD TV, and refrigerator) in three countries (US, Germany, and Russia). In order to explain and forecast the behavior of personal device or system users, individual cultural characteristics must be measured, and depending on the target device or system, measurements must be measured independently. Through this suggestion, this study hopes to provide new and useful perspectives for future IS research.

Effects of hydrocolloids on wheat flour rheology (Hydrocolloid의 첨가가 밀가루 반죽의 특성에 미치는 영향)

  • 임경숙;황인경
    • Korean journal of food and cookery science
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    • v.15 no.3
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    • pp.203-209
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    • 1999
  • The effect of several hydrocolloids on the rheological behavior of wheat flour was investigated. The influence of the selected hydrocolloids (alginate, carrageenan, CMC, guar, locustbean and xanthan) on wheat flour was tested by using two different techniques; amylograph and texture analyzer. In order to have a general overview of their effects hydrocolloids were chosen from different sources implying a broad diversity of chemical structures. The hydrocolloid addition decreased the brightness(L) but increased yellowness(b). The interaction between hydrocolloid and flour produces a slight modification of the amylogram parameters, being the most clearly affected parameter breakdown, which is increased by carrageenan, guar and xanthan. Hardness and cutting force were augmented by hydrocolloid addition, while springeness was decreased except guar and locustbean. In summary, when looking for the improvement of the noodle texture, guar, locustbean are the best candidate additives due to their effects on pasting and texture properties. These hydrocolloids increase the hardness, cutting force, gumness, chew-ness, so were thought to increase the eating quality. So, each tested hydrocolloid affected in a different way the rheological properties of wheat flour, the results obtained are important for the appropriate use of these hydrocolloid as ingredients in the noodle making process.

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