• Title/Summary/Keyword: Gap and Level Difference

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Gender Differences in Geometry of the TIMSS 8th Grade Mathematics Based on a Cognitive Diagnostic Modeling Approach (인지진단모형을 적용한 TIMSS 8학년 수학 기하 영역의 성차 분석)

  • Yi, Hyun Sook;Ko, Ho Kyoung
    • School Mathematics
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    • v.16 no.2
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    • pp.387-407
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    • 2014
  • Gender differences have been given major attention in mathematics education in the context of pursuing gender equity in instructional and learning environment. It had been traditional belief that male students would outperform female students in mathematics, especially in the areas as geometry. This belief has been given doubts by cumulated empirical evidences that gender differences are gradually diminishing or even reversing its direction as time goes on. In this study, gender differences in geometry were explored using TIMSS 8th grade mathematics data administered in TIMSS 2003, 2007, and 2011, based on a cognitive diagnostic modeling(CDM) approach. Among various CDM models, the Fusion model was employed. The Fusion model has advantages over other CDM models in that it provides more detailed information about gender differences at the attribute level as well as item level and more mathematically tractable. The findings of this study show that Attribute 3(Three-dimensional Geometric Shapes) revealed statistically significant gender differences favoring male students in TIMSS 2003 and 2007, but did not show significant differences in TIMSS 2011, which provides an additional empirical evidence supporting the recent observation that gender gap is narrowing. In addition to the general trends in gender differences in geometry, this study also provided affluent information such as gender differences in attribute mastery profiles and gender differences in relative contributions of each attribute in solving a particular item. Based on the findings of the CDM approach exploring gender differences, instructional implications in geometry education are discussed.

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Tensile Performance of Machine-Cut Dovetail Joint with Larch Glulam (낙엽송집성재를 이용한 기계프리커트 주먹장접합부의 인장성능)

  • Park, Joo-Saeng;Hwang, Kweon-Hwan;Park, Moon-Jae;Shim, Kug-Bo
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.3
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    • pp.199-204
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    • 2010
  • Members used for the Korean traditional joints have been processed by handicraft, especially with domestic red pine species. Dovetail joint is most commonly used in woodworking joinery and traditional horizontal and vertical connections. It is able to be processed much easier to cut by handicraft and machines. However, although it is processed straight forwards, it requires a high degree of accuracy to ensure a snug fit. Also, tenons and mortises must fit together with no gap between them so that the joint interlocks tightly. A few scientific studies on the dovetail joints have been conducted so far. For the effective applications of traditional joints and domestic plantation wood species, dovetail joints were assembled by larch glulam members processed by machine pre-cut. To identify the tensile properties of through dovetail joints, larch glulam with 150 150mm in cross section were prepared. Furthermore, various geometric parameters of dovetai joints such as width, length, and tenon angle, were surveyed. The ends in the mortise was cracked mainly at a low strength level in the control specimens without reinforcements. The maximum tensile strengths of reinforced specimens considering real connections such as capital joint and headpiece on a column, increasedby handicraft, especially with domestic red pine species. Dovetail joint is most commonly used in woodworking joinery and traditional horizontal and vertical connections. It is able to be processed much easier to cut by handicraft and machines. However, although it is processed straight forwards, it requires a high degree of accuracy to ensure a snug fit. Also, tenons and mortises must fit together with no gap between them so that the joint interlocks tightly. A few scientific studies on the dovetail joints have been conducted so far. For the effective applications of traditional joints and domestic plantation wood species, dovetail joints were assembled by larch glulam members processed by machine pre-cut. To identify the tensile properties of through dovetail joints, larch glulam with 150 150mm in cross section were prepared. Furthermore, various geometric parameters of dovetai joints such as width, length, and tenon angle, were surveyed. The ends in the mortise was cracked mainly at a low strength level in the control specimens without reinforcements. The maximum tensile strengths of reinforced specimens considering real connections such as capital joint and headpiece on a column, increased by two times with shear failures on the tenon than the control specimens. The maximum tensile strength was obtained in the specimen of 25 degrees, and no difference was observed in the changes of neck widths.

Comparative accuracy of new implant impression technique using abutments as impression copings with an angulated implant model (경사지게 식립된 임플랜트 모형에서 지대주를 인상용 코핑으로 이용한 새로운 인상법의 정확성 비교 연구)

  • Lee, Hyeok-Jae;Kim, Chang-Whe;Lim, Young-Jun;Kim, Myung-Joo
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.2
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    • pp.201-208
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    • 2008
  • Statement of problem: A new implant impression technique which use abutments as impression coping, and use resin cement as a splinting material was described. Accuracy of this technique was compared with conventional closed tray and resin splinted open tray technique for a $15^{\circ}$ angled 3-implant model Material and methods: A dental stone master model with 3 linearly positioned implant analogue and a reference framework which was passively fitted to it were fabricated. The center analogue was perpendicular to the plane of model and the outer analogues had a $15^{\circ}$angulation forward or backward. 10 closed tray impressions, 10 resin splinted open tray impressions, 10 abutment-resin framework cementation impressions and 10 abutment-metal framework cementation impressions were made with additional silicone material and poured with dental stone. A light microscope with image processing was used to record the vertical gap dimension between reference framework and analogue of duplicated cast made with each 4 impression techniques. Statistical analysis used one-way ANOVA with post-hoc tests Tukey test of .05 level of significance Results: Significant difference in the vertical gap dimension was found between closed tray technique; 74.3 (${\pm}33.4$)${\mu}m$ and resin splinted open tray technique, and two other new technique. (P<.05) Abutment-metal framework cementation technique;42.5 (${\pm}11.9$)${\mu}m$ was significantly different from resin splinted open tray technique. (P<.05) Abutmentresin framework cementation technique;51.0 (${\pm}14.1$)${\mu}m$ did not differ significantly from resin splinted open tray technique;50.3 (${\pm}16.9$)${\mu}m$. (P>.05) Conclusion: Within limitations of this study, the accuracy of implant level impressions of resin splinted open tray technique was superior to that of closed tray technique. A new technique using abutment and metal framework cementation was more accurate than resin splinted open tray technique.

The Effect of Emphatic Ability and Family Strengths on Happiness in Adolescents (청소년의 공감능력과 가족건강성이 행복감에 미치는 영향)

  • Yang, Yeongmun;Shin, Hyoshick;Lee, Seonjeong
    • Journal of Korean Home Economics Education Association
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    • v.29 no.4
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    • pp.49-64
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    • 2017
  • The purpose of this study was to explore ways to help improve adolescents' happiness by exploring the influences of emphatic ability and family strengths on happiness. This subjects were 514 middle school students living in Gwangju. Data were collected from self-report questionnaires and analyzed with SPSS 22.0 program. The major findings were as follows; First, the adolescents' emphatic ability('viewpoint', 'identity', 'emphatic interest'), family strengths('family respect and affection', 'role sharing and problem solving', 'communication and bonds', 'financial stability') and happiness scores were higher than the median(3.00). Emphatic ability('viewpoint', 'identity', 'emphatic interest', 'personal suffering') and family strengths('communication and bonds') showed significant difference according to gender. Second, the adolescents' happiness was influenced by 'family respect and affection', 'role sharing and problem solving', 'financial stability', 'personal suffering', 'identity', and 'emphatic interest'. Adolescents' happiness was explained about 39% by these variables. In other words, the higher family respect and affection, both higher role sharing and problem solving and higher financial stability, with lower personal suffering and higher identity and higher emphatic interest showed the higher happiness. These findings demonstrate the emphatic ability and family strengths in adolescents influence on the level of happiness. As such, in order to improve the happiness of adolescents, it is necessary to energize those programs focus on the forming healthy family relationships and to design finance assistance programs that could attempt to minimise financial gap. Additionally, it is necessary to develop programs aimed to enhance emphatic ability and continue such programs in homes as well as at schools. Finally, it is necessary to implement curriculum that may improve family strengths and emphatic ability, which have influenced on the happiness in adolescents. Since the subject "Technology & Home Economics" helps to enhance family strengths, emphatic ability and eventually amplifies the happiness, it is necessary to expand and reinforce it as well as to make it a mandatory subject.

A Study on the Image of Dental Hygienists in Dental Patients and Caregivers (치과환자 및 보호자가 인지한 치과위생사 이미지)

  • Kang, Boo-Wol
    • Journal of Korean society of Dental Hygiene
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    • v.7 no.2
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    • pp.197-211
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    • 2007
  • The purpose of this study was to examine the image of dental hygienists. The subjects in the study were 396 patients and their caregivers who visited 14 dental hospitals and dentists' offices in and around Seoul. After a survey was conducted, the following findings were given: 1. The people investigated gave a mean of 4.0 to the image of dental hygienists. Dental hygienists rated highest in terms of looking neat and tidy(4.33), and were given the lowest marks in arbitrary job performance(3.46). 2. There appeared four different types of dental hygienist images, which made a 59.824 prediction of the image of dental hygienists in general. A typical image(4.11) was most dominant, followed by professional one(4.07), personal one(4.01) and social one(3.73). 3. The relations between the general characteristics of the respondents and their image of dental hygienists could be described as below: 1) By age, those who were in their 60s(4.12) had the best image of dental hygienists, and the teenagers(3.90) had the worst image of them. 2) By gender, the men(4.05) looked at dental hygienists more positively than the women(3.96). They had a significantly different opinion on the social image of dental hygienists according to gender(pE0.05). 3) By marital status, the married people(4.00) had a better image of dental hygienists than the unmarried ones(3.95). 4) As for the influence of the type of dental institutions, they had a more favorable image of dental hygienists in dentists' offices(4.13) than in dental hospitals(3.88). There was a broad significant difference in the way they looked at the professional and personal images of dental hygienists according to the type of dental institutions(pE0.001). 5) As to the impact of educational level, those who received community-college or higher education(4.01) had the best image of dental hygienists, and those who received middle-school or lower education(3.91) had the worst image of them. 6) By occupation, the government workers and students(4.07) had the best image of dental hygienists, and the company employees(3.90) had the worst image of them. They took a significantly different view of the social image of dental hygienists according to occupation(pE0.05). 7) Concerning the impact of the frequency of receiving dental treatment, the respondents who had received it seven times or more(4.16) had the best image of dental hygienists, and those who hadn't(3.79) the worst image of them. There was a wide significant gap according to that frequency. The way they looked at the typical, social and professional images of dental hygienists was quite different significantly according to that frequency as well(pE0.001). 8) As for the influence of whether they were accompanied by caregivers or not, the people who weren't accompanied by caregivers(3.99) had a better image of dental hygienists than those who were(3.97).

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Estimating milk production losses by heat stress and its impacts on greenhouse gas emissions in Korean dairy farms

  • Geun-woo, Park;Mohammad, Ataallahi;Seon Yong, Ham;Se Jong, Oh;Ki-Youn, Kim;Kyu-Hyun, Park
    • Journal of Animal Science and Technology
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    • v.64 no.4
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    • pp.770-781
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    • 2022
  • Meteorological disasters caused by climate change like heat, cold waves, and unusually long rainy seasons affect the milk productivity of cows. Studies have been conducted on how milk productivity and milk compositions change due to heat stress (HS). However, the estimation of losses in milk production due to HS and hereby environmental impacts of greenhouse gas (GHG) emissions are yet to be evaluated in Korean dairy farms. Dairy milk production and milk compositions data from March to October 2018, provided by the Korea Dairy Committee (KDC), were used to compare regional milk production with the temperature-humidity index (THI). Raw data for the daily temperature and relative humidity in 2018 were obtained from the Korea Meteorological Administration (KMA). This data was used to calculate the THI and the difference between the maximum and minimum temperature changing rate, as the average daily temperature range, to show the extent to which the temperature gap can affect milk productivity. The amount of milk was calculated based on the price of 926 won/kg from KDC. The results showed that the average milk production rate was the highest within the THI range 60-73 in three regions in May: Chulwon (northern region), Hwasung (central region), and Gunwi (southern region). The average milk production decreased by 4.96 ± 1.48% in northern region, 7.12 ± 2.36% in central region, and 7.94 ± 2.57% in southern region from June to August, which had a THI range of 73 or more, when compared to May. Based on the results, the level of THI should be maintained like May. If so, the farmers can earn a profit of 9,128,730 won/farm in northern region, 9,967,880 won/farm in central region, and 12,245,300 won/farm in southern region. Additionally, the average number of cows raised can be reduced by 2.41 ± 0.35 heads/farm, thereby reducing GHG emissions by 29.61 ± 4.36 kg CO2eq/day on average. Overall, the conclusion suggests that maintaining environmental conditions in the summer that are similar to those in May is necessary. This knowledge can be used for basic research to persuade farmers to change farm facilities to increase the economic benefits and improve animal welfare.

A Study on the Characteristic Factors of Logistics Companies and the Wage Gap of Workers in Korea (우리나라 물류기업 특성요인과 근로자 임금격차에 대한 분석연구)

  • Koo, Kyoung-mo
    • Journal of Korea Port Economic Association
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    • v.38 no.2
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    • pp.139-152
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    • 2022
  • In this paper, samples are collected for individual companies and the factors affecting worker wages (average annual salary) are analyzed in depth. In addition to the average annual salary of workers in a company, we would like to conduct an in-depth analysis of the average annual salary of first-time employees. Specifically, we tried to explain the size of companies, the production structure of capital and labor, and the impact of business on the average annual salary of first-time, college, and graduate school graduates by educational background of first-time employees. The difference in average annual salary of first-time employees of logistics companies is a decisive factor in the main project on sales, and first-time graduates and college graduates provided high salaries in the overseas passenger cargo transportation, port operation, and unloading management, and low salaries in the land cargo and warehouse industries. n addition, Korean logistics companies had relationships between the location of the headquarters, the number of employees, the proportion of labor costs to sales, and the four characteristic factors of the main business on sales. This fact is that Seoul-based foreign passenger cargo transportation, corporate logistics agency, complex transportation, and international transportation relay are large companies, with a low proportion of labor costs and a higher proportion of capital, technology, and information-intensive investments.

Pro-Environmental Food Consumption Behavior Pattern (환경친화적 음식소비행동 유형)

  • 서정희;홍순명;황혜진
    • Journal of the Korean Home Economics Association
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    • v.38 no.12
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    • pp.131-143
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    • 2000
  • This research aims to examine the pro-environmental food consumption behavior of two groups; the housekeepers and the restaurant cooks. The rationale for choosing these groups as target of research lies in the fact that they are expected to be the most active subject for enhancing the desirable culture of food consumption, through their close involvement in the whole process of food consumption in society. This study assumes the four areas of activity to be the meaningful categories in the investigation of the pro-environmental food consumption behaviour; planning of menu and purchasing the food materials, cooking, eating, and disposal of the leftover. By using these four categories, we attempt to provide with the empirical typology of pro-environmental food consumption behaviour and the analysis of the relations of it with socio-demographical variables. Their pro-environmental behaviors are divided into four types: $\circled1$ The positive awareness of pro-environmental cooking and eating, $\circled2$ The positive awareness of pro-environmental food consumption behavior, $\circled3$ The passive awareness of pro-environmental cooking and eating, $\circled4$ The passive awareness of pro-environmental food consumption behavior. There is no significant difference among the numbers of the cases that belong to each behavioral type. Seen in overall, however, we can say that the larger number of the cases belong to the passive type of behavior. Two socio-demographical variables of tole housekeepers and the restaurant cooks show significant corelations with the behavioral types of pro-environmental food consumption with the confidence level P<0.05, but there is no significant co-relations in other variables like gender, marital status, age, income, Engel coefficient, education. We also found that there is no great gap between the housekeepers and the restaurant cooks in their positive awareness of pro-environmental food consumption, the percentage of each group belonging to the type being 51.9% and 48.1%, respectively, but that the former shows much greater number than the latter in belonging to the passive awareness type of the pro-environmental food consumption, 75.3% and 24.7%, respectively. Although the restaurant cooks can be said to be more ego-friendly than the housekeepers, if we consider the rapidly growing trend of outgoing-diner, more efforts should be exerted to develop the education and advertisement program for enhancing the restaurant cook's pro-environmental awareness and propagating the desirable food consumption cloture.

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Quality and Yield Characteristics of Potato (Solanum tuberosum L.) Grown at Paddy Field in Spring Season

  • Im, Ju Sung;Cho, Ji Hong;Chang, Dong Chil;Jin, Yong Ik;Park, Young Eun;Chun, Chung Gi;Kim, Dong Un;Yu, Hong Seob;Lee, Jong Nam;Kim, Myung Jun
    • Horticultural Science & Technology
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    • v.31 no.1
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    • pp.24-31
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    • 2013
  • This study was conducted to determine the characteristics of quality and yield in potatoes grown at paddy field before rice transplantation during the spring season. Three potato cultivars ('Jowon', 'Haryeong', and 'Goun') were grown in Gangneung (asl 5 m) and Seocheon (asl 20 m). In both locations, weather condition belonged to the fourth zone (spring cropping) in potato production location's distribution of Korea. Daily mean soil temperature in both the locations was $0.2-0.6^{\circ}C$ lower than air temperature, while soil moisture was adequate level to potato growth in spite of spring drought. TR ratio was not affected by location, but by cultivar. Specific gravity, starch content, dry matter rate, and yield were significantly influenced by location and by cultivar. There was no difference in total tuber number by location, however there was a large gap in marketable tuber yield according to locations and cultivars. There were high negative relationships between yield and main qualities such as dry matter rate and starch content, while high positive correlation was observed between main qualities. It was possible to produce potato before rice transplanting at drained paddy fields located in representative two locations of potato spring cropping and their characteristics in growth and quality were similar to those generally well known in upland cultivation. Paddy field was thought to be more favorable than upland in terms of available soil moisture supply against spring drought. Further research, however, was needed to increase soil temperature and also preliminary review on proper cultivar according to location seemed to be needed for high yield.

Articulatory Attributes in Korean Nonassimilating Contexts

  • Son, Minjung
    • Phonetics and Speech Sciences
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    • v.5 no.1
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    • pp.109-121
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    • 2013
  • This study examined several kinematic properties of the primary articulator (the tongue dorsum) and the supplementary articulator (the jaw) in the articulation of the voiceless velar stop (/k/) within nonassimilating contexts. We examined in particular the spatiotemporal properties (constriction duration and constriction maxima) from the constriction onset to the constriction offset by analyzing a velar (/k/) followed by the coronal fricative (/s/), the coronal stop (/t/), and the labial (/p/) in across-word boundary conditions (/k#s/, /k#t/, and /k#p/). Along with these measurements, we investigated intergestural temporal coordination between C1 and C2 and the jaw articulator in relation to its coordination with the articulation of consonant sequences. The articulatory movement data was collected by means of electromagnetic midsagittal articulometry (EMMA). Four native speakers of Seoul Korean participated in the laboratory experiment. The results showed several characteristics. First, a velar (/k/) in C1 was not categorically reduced. Constriction duration and constriction degree of the velar (/k/) were similar within nonassimilating contexts (/k#s/=/k#t/=/k#p/). This might mean that spatiotemporal attributes during constriction duration were stable and consistent across different contexts, which might be subsequently associated with the nontarget status of the velar in place assimilation. Second, the gestural overlap could be represented as the order of /k#s/ (less) < /k#p/ (intermediate) < /k#t/ (more) as we measured the onset-to-onset lag (a longer lag indicated shorter gestural overlap.). This indicates a gestural overlap within nonassimilating contexts may not be constrained by any of the several constraints including the perceptual recoverability constraint (e.g., more overlap in Front-to-Back sequences compared to the reverse order (Back-to-Front) since perceptual cues in C1 can be recovered anytime during C2 articulation), the low-level speech motor constraint (e.g., more overlap in lingual-nonlingual sequences as compared to the lingual-lingual sequences), or phonological contexts effects (e.g., similarity in gestural overlap within nonassimilating contexts). As one possible account for more overlap in /k#t/ sequences as compared to /k#p/, we suspect speakers' knowledge may be receptive to extreme encroachment on C1 by the gestural overlap of the coronal in C2 since it does not obscure the perceptual cue of C1 as much as the labial in C2. Third, actual jaw position during C2 was higher in coronals (/s/, /t/) than in the labial (/p/). However, within the coronals, there was no manner-dependent jaw height difference in C2 (/s/=/t/). Vertical jaw position of C1 and C2 was seen as inter-dependent as higher jaw position in C1 was closely associated with C2. Lastly, a greater gap in jaw height was associated with longer intergestural timing (e.g., less overlap), but was confined to the cluster type (/kp/) with the lingual-nonlingual sequence. This study showed that Korean jaw articulation was independent from coordinating primary articulators in gestural overlap in some cluster types (/k#s/, /k#t/) while not in others (e.g., /k#p/). Overall, the results coherently indicate the velar stop (/k/) in C1 was robust in articulation, which may have subsequently contributed to the nontarget status of the velar (/k/) in place assimilation processes.