• Title/Summary/Keyword: Consistency test

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Influence of Grease Consistency on the Wear of Gear Surfaces

  • Li, Chen-Xiao;Park, Haneum;Lee, Chul-Hee
    • Tribology and Lubricants
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    • v.38 no.3
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    • pp.115-119
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    • 2022
  • This paper selected three kinds of grease with the same type but different consistency for the experiment. The purpose of the experiment is tested the effect of different consistency of grease on the wear of the gear surface. Different torque test groups were selected in the test, and the lubrication effect of different greases was tested in the test groups with the same torque. After each set of tests, the wear of the gear surfaces was observed and recorded. The data recorded in the experiment included the area of the wear area on the gear surface, the type of wear and the volume of wear. After the test, the gear surface roughness was measured. By calculating the wear volume, the effects of different concentrations of grease on the gear surface wear were compared. The experimental results show that under different stress conditions, the consistency of the grease has a great influence on the lubricating effect of the gear surface and the gear wear. Under the condition with low speed and high torque, different grease consistency affect the gear surface wear, the high consistency grease can reduce the wear of the gear surface, so that the gear can get better lubrication effect during the work.

Consistency of a Modified W Test for Exponentiality

  • Kim, Namhyun
    • Communications for Statistical Applications and Methods
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    • v.9 no.3
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    • pp.629-637
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    • 2002
  • Shapiro and Wilk(1972) developed a test for exponentiality with origin and scale unknown. The procedure consists of comparing the generalized least squares estimate of scale with the estimate of scale given by the sample variance. However the test based on the statistic is inconsistent Kim(2001a) proposed a modified Shapiro-Wilk's test statistic using the ratio of two asymptotically efficient estimators of scale. In this paper, we study the consistency of the proposed test.

Consistency Test in the House of Quality using Permutation Test (순열검정을 이용한 품질의 집의 일관성 검정)

  • Kim, Kyungmee O.
    • Journal of Korean Institute of Industrial Engineers
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    • v.34 no.1
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    • pp.42-48
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    • 2008
  • The house of quality (HOQ) involves subjective and ambiguous information typically through a likert scale, It isimportant to validate consistency of such input in the HOQ before rating the fmal importance of technicalrequirements, Previously, a methodology was developed to test the consistency of relationship strengths in theHOQ between roof matrix and relationship matrix. We described disadvantages of the previous method andpropose a new approach based on the permutation test. Advantages of the proposed method are illustrated withan example.

Optimum Compaction Test of Roller Compacted Concrete Pavement (롤러전압 콘크리트포장의 적정 다짐실험 방안 고찰)

  • Chung, Gun Woo;Lee, Seung Woo
    • International Journal of Highway Engineering
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    • v.17 no.3
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    • pp.27-33
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    • 2015
  • PURPOSES : To ensure appropriate RCC properties with sufficient strength development and workability, it is necessary to secure a proper level of consistency. It is also necessary to secure maximum dry density, which is an important factor for increasing the interaction of aggregate interlocking, leading to an augmentation of RCC strength. On the other hand, the dry density of RCC can be changed owing to the compaction conditions, water content, and particle size distribution. A Proctor test and a modified Proctor test were used for determining the optimum water content needed to achieve maximum dry density with different amounts of compaction energy. A Vebe test, on the other hand, was used for checking the level of consistency, which is important for producing a workable mixture. METHODS : To confirm the degree of compaction at various particle sizes, RCC mixtures with different sand/aggregate ratios were evaluated. The Proctor test and modified Proctor test were applied to these mixtures to check the effect of the aggregate gradation and compaction energy on the maximum dry density and optimum water content. During each test, three specimens were produced for all types of water content under each aggregate gradation. A compaction curve and the optimum water content and maximum dry density for each aggregate gradation were then obtained for both tests. The range of water content for the appropriate consistency of each aggregate gradation was determined through a Vebe test. The optimum water content was then evaluated based on this range. RESULTS : The compaction test results show that the modified Proctor test provides a higher maximum dry density and lower optimum water content compared with the standard Proctor test. For the modified Proctor test, two cases of aggregate gradation (s/a = 30% and 70%) had the optimum water contents outside of the appropriate water content range. For the standard Proctor test, on the other hand, none of aggregate gradations provided the optimum water content within the desired range. CONCLUSIONS : The modified Proctor test should be used for an RCC mixture design because it can provide adequacy between maximum dry density and consistency. Moreover, the compaction roller has become highly developed for higher compaction energy.

A Study of stability in ratings for clothing styles (의복스타일에 따른 평가의 재현성 차이에 관한 연구)

  • 유경숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.27 no.8
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    • pp.924-934
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    • 2003
  • The aim of the present study was to measure intra-individual consistency in clothing style evaluation and to examine its relation to the ratings. For this study, a pilot test was conducted to 50 clothing majored university students to explore the stimulus of‘cute’,‘casual’,‘sexy’,‘elegant’,‘intelligent’,‘formal’,‘romantic’,‘individual’,‘refined’for the 9 each image styles from the 32 spring wears in fashion magazine$\boxDr$FARBE$\boxUl$(March, 2000). On the basis of the preliminary survey, the question items explored the 15 pairs of bipolar adjectives as seven-point Likert type. The main survey was preceded 94 female and 111 men of university students from March 13 to 24 in 2000, twice for 7-days interval. As a result of analyzing of correlation coefficients between the two ratings for each subjects, intra-individual consistency in the evaluation, ranged from -.11 to .87 and mean coefficient was .64 of female and .20 to .76 and mean coefficient was .57 of male. Female had higher intra-individual consistency in the evaluation than male. Based on the coefficients, the subjects were classified into three groups: high, medium, and low intra-individual consistency. Analysis of variance of mean ratings by the three groups revealed that significant difference existed in 42% of female and 25% of male in 135 combinations of 9 clothing and 15 semantic differential scales. There was an apparent tendency that subjects of female with high intra-individual consistency were mostly definitely to evaluate clothing, whereas the ones with low were least. But male shows opposit trend compare to each groups of female. The result of this study, it was found that female rated higher intra-individual consistency and definition in the two times evaluations than male and among the semantic differential scales'consistency differ depending on style and gender. It is believed that the result of this study is helpful clothing image evaluation, and clothing image selection tendency.

A Study on the Importance of Measures for Improving PLM System Usage (PLM 시스템 활용도 향상 방안의 중요도에 관한 연구)

  • Yoo, Jong Kwang;Rim, Seong Taek;Min, Dai Hwan
    • The Journal of Information Systems
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    • v.31 no.1
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    • pp.239-269
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    • 2022
  • Purpose This paper attempts to identify items for improving the usage of PLM(Product Lifecycle Management) systems and suggests ways to prioritize improvement items on the basis of importance. It also tries to find out differences in the importance of improvement items due to the company size, the industry, the job, or the PLM solution. Design/methodology/approach Through a survey from participants to a PLM System Conference, data were collected from a sample of 181 users who had the previous experience in using a PLM system. In order to figure out the differences in the importance among user groups, the F-test with the Scheffe test as a post-hoc analysis was used in case of equal variances and the Welch test with the Dunnett T3 test was used in case of unequal variances. Findings This study sorted out 25 improvement ideas according to their importance assessed by the PLM system users. The top five ideas are improving data consistency, error minimization, fast system response time, enhancing user recognition, and business process improvement. The support group puts higher importance than the general user group in data consistency, fast system response time, enhancing user recognition, business process improvement, dedicated team for data consistency, continuous support from management, hardware performance upgrade, output linkage to other systems, and shortening problem solving duration. The largest company group attaches significantly higher weights than the smallest company group to data consistency, error minimization, fast system response time, business process improvement, dedicated team for data consistency, security with proper access management, output linkage to other systems, and better user interface.

Influence of Various Waxes on Consistency of W/O Type Cream (왁스류(類)가 유중빙형(油中氷型)크림의 조도(稠度)에 미치는 영향)

  • Bae, Bong-Jean;Choi, Young-Uk;Kim, Johng-Kap
    • Journal of Pharmaceutical Investigation
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    • v.15 no.3
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    • pp.121-129
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    • 1985
  • Influences of various waxes on the consistency of cream was investigated by inspections through microscope, rheometer and sensory test. Fatty acids, higher fatty alcohols, hydrocarbons, and some of natural waxes were used in this experiment. Most above waxes showed good state of emulsion at low concentration, but at higher concentration $(7.0{\sim}8.0%)$, they showed not only an unstable emulsion state but also a critical point of content in consistency. At this critical point of content, the consistency of w/o type cream was increased irregularly. So, it could be identified that consistency of a w/o type cream was strongly dependent on kinds and contents of waxes in continuous phase.

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An Analysis of Current Science Instruction Consistency by Micro Instructional Design Theory (미시적 교수설계이론에 의한 현행 과학교수의 일관성 분석 - 과학 I (하) 'V.l.태양계' 단원을 중심으로 -)

  • Paik, Seoung-Hey;Kim, Seung-Hwa;Hong, Sung-Il;Yang, II-Ho;Lee, Jae-Cheon
    • Journal of The Korean Association For Science Education
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    • v.13 no.3
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    • pp.366-376
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    • 1993
  • In this study, a part of high school science instructional materials is evaluated by Instructional Quality Profile(IQP) based on the Merrill's Component Display Theory(CDT). The CDT is based on the Gagne's assumption of different conditions of learning for different outcomes. The IQP enables the user to check both the consistency and adequacy of existing cognitive instruction. The IQP can be used to predict student performance, and also to design and develop new instructional materials. The instructional components are classified according to 5 task levels; An Use-Generalities on Newly Encountered Examples(UGeg), A Remember-Paraphrased-Generalities(RpG), A Remember-Verbatim-Generalities(RvG), A Remember-Paraphrased-Examples (Rpeg). A Remember-Verbatim-Examples (Rveg). The analyses are composed of 3 parts; Justifying the task level of objectives, Objective-test consistency, and Test-presentation consistency. The objectives, the presentations and the tests given in a teacher's guide and a textbook are analyzed. The results show that the task levels and the content levels of the objectives are not consistent with those of the tests. And the indices of the test-presentation consistency indicate the presentation problems of the instructional materials.

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STUDY ON THE PROPERTIES OF GYPSUM-BONDED DENTAL INVESTMENTS (치과용 석고계 매몰재의 특성에 관한 연구)

  • Kim, Kyoung-Sun;Woo, Yi-Hyung;Choi, Boo-Byung
    • The Journal of Korean Academy of Prosthodontics
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    • v.28 no.1
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    • pp.137-163
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    • 1990
  • The properties of a investment material can be described by the consistency at the slurry state, the setting time, the compressive strength and the thermal expansion during the casting. In this study the effect of the production parameters which are included the ratio of quartz and cristobalite, the content of binder, the water powder ratio and the content and concentration of additives on the Properties of the gypsum-bonded investments has been investigated with help of the consistency test, the vicat needle test, the compressive strength test, the thermal expansion test, x-ray diffraction and DTA thermal differential test. The experimental results showed that the constitution of a investment with W/P ratio of 0.34, 30% of gypsum, 0.8% aluminium sulfate, 2% magnesium sulfate, 0.6% sodium phosphate was adapted for the properties of the KDA Spec. No. 13 type I investment. The important experimental results are summarized as follows. 1. The consistency of the investment decreased with increasing amount of aluminium sulfate and decreasing amount of sodium phosphate. An addition of magnesium sulfate up to 2% an increase of the consistency was shown. But 3% magnesium sulfate in investment showed a decrease of the consistency. The consistency did not vary significantly with a variation of the content of gypsum and cristobalite and the W/P ratio. 2. Aluminium sulfate and the magnesium sulfate promoted the hardening and the aluminium phosphate delayed the hardening. The setting time increased with amount of gypsum. The effect of the matrix on the setting time was insignificant. With the W/P ratio of 0.34 the setting time was 14 min. 3. The compressive strength decreased with the amount of aluminium sulfate up to 0.25% and increased with the amount of aluminium sulfate greater than 3%. The compressive strength decreased as decreasing the amount of magnesium sulfate and gypsum and as increasing the W/P ratio. The effect of the refractory on the compressive strength was also not significant. With the W/P ratio of 0.34 the compressive strength was $34Kg/mm^2$. 4. The 1st thermal expansion was found at the temperature near and the steady state or the contraction stage was found at the temperature between $250^{\circ}C$ and $500^{\circ}C$. After this stage the 2nd thermal expansion took place at the temperature near $500^{\circ}C$. The amount of thermal expansion increased with decreasing the content of magnesium sulfate, aluminium sulfate and gypsum and the W/P ratio. And the amount of thermal expansion increased as the content of sodium phosphate and cristobalite. With the W/P ratio of 0.34 the amount of total expansion was 1.2%.

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STUDY ON THE PROPERTIES OF GYPSUM-BONDED DENTAL INVESTMENTS (치과용 석고계 매몰재의 특성에 관한 연구)

  • Kim, Kyoung-Sun;Woo, Yi-Hyung;Choi, Boo-Byung
    • The Journal of Korean Academy of Prosthodontics
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    • v.29 no.1
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    • pp.139-165
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    • 1991
  • The properties of a investment material can be described by the consistency at the slurry state, the setting time, the compressive strength and the thermal expansion during the casting. In this study the effect of the production parameters which are included the ratio of quartz and cristobalite, the content of binder, the water powder ratio and the content and concentration of additives on the properties of the gypsum-bonded investments has been investigated with help of the consistency test, the vicat needle test, the compressive strength test, the thermal expansion test, x-ray diffraction and DTA thermal differential test. The experimental results showed that the constitution of a investment with W/P ratio of 0.34, 30% of gypsum, 0.8% aluminium sulfate, 2% magnesium sulfate, 0.6% sodium phosphate was adapted for the properties of the KDA Spec. No. 13 type I investment. The important experimental results are summarized as follows. 1. The consistency of the investment decreased with increasing amount of aluminium sulfate and decreasing amount of sodium phosphate. An addition of magnesium sulfate up to 2% an increase of the consistency was shown. But 3% magnesium sulfate in investment showed a decrease of consistency. The consistency did not vary significantly with a variation of the content of gypsum and cristobalite and the W/P ratio. 2. Aluminium sulfata and the magnesium sulfate promoted the hardening and the aluminium phoshpate delayed the hardening. The setting time increased with amount of gypsum. The effect of the matrix on the setting time was insignificant. With the W/P ratio of 0.34 the setting time was 14 min. 3. The compressive strength decreased with the amount of aluminium sulfate up to 0.25% and increased with the amount of aluminium sulfate greater than 3%. The compressive strength decreased as decreasing the amount of magnesium sulfate and gypsum and as increasing the W/P ratio. The effect fo the refractory on the compressive strength was also not significant. With the W/P ratio of 0.34 the compressive strength was $34Kg/mm^2$. 4. The 1st thermal expansion was found at the temperature near $250^{\circ}C$ and the steady state or the contraction stage was found at the temperature between $250^{\circ}C$ and $500^{\circ}C$. After this stage the 2nd thermal expansion took place at the temperature near $500^{\circ}C$. The amount of thermal expansion increased with decreasing the content of magnesium sulfate, aluminium sulfate and gypsum and the W/P ratio. And the amount of thermal expansion increased as the content of sodium phosphate ad cristobalite. With the W/P ratio of 0.34 the amount of total expansion was 1.2%.

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