• Title/Summary/Keyword: Difference-in-Differences(DID)

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Growth Characteristics and DPPH Radical Scavenging Activity of Lettuce 'Fidel' in Plant Factory Using Activated Mineral Groups and Light-emitting Diode Lights

  • Song, Tae-Eui;Park, Seong-Jik;Moon, Joon-Kwan;Kim, In Soo;Lee, Chang Hee
    • Korean Journal of Plant Resources
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    • v.32 no.3
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    • pp.228-236
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    • 2019
  • This study is conducted to investigate the effects of growth characteristics (GC) and DPPH radical scavenging activity (DRSA) of the heading lettuce 'Fidel' depending on four concentrations of activated mineral groups (AMG: 1.6% active minerals and 0.03% CaO) added to basic nutrient solutions (diluted by 0, 0.05, 0.1, and 0.2%) and on four different light-emitting diodes (LED; B:R:W ratio = 0:1:12, 0:1:9, 0:5:5, and 2:3:5). Both 0.1 and 0.2% AMG showed better GC of lettuce in plant width, plant length, leaf width, leaf length, and the number of leaves than those of other AMG, while leaf thickness and chlorophyll value did not show significant difference among all AMG. Moreover, 0.1 and 0.2% AMG showed heavier shoot fresh weights than those of other AMG. As for the combinations of AMG and LED, B0:R5:W5 showed the best lettuce GC regardless of AMG compared to other AMG and LED combinations. As shown in the above results of LED, although there was a difference in lettuce growth by LED, the differences of lettuce growth by AMG were statistically significant. The DRSA was the highest at 82.8% in B2:R3:W5, followed by B0:R5:W5 at 77.8%. LED showed differences but AMG did not affect DRSA. Therefore, the optimal conditions in plant factory for GC and DRSA of the lettuce were 0.1% AMG and B0:R5:W5.

Widowed elderly's dating experience and related variables: focusing on gender difference (홀로된 노인의 이성교제경험과 관련변인 - 성별 차이를 중심으로)

  • Yi, Yeong Sug
    • Korean Journal of Human Ecology
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    • v.22 no.4
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    • pp.609-618
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    • 2013
  • The purpose of this study is to explore gender differences in elderly's dating experience and related variables. 427 elderly of age 65 or older participated. The results are as follows. 1. 80% of widowed elderly had no dating experience, and far more elderly men than women had dating experience. 2. Attitudes towards dating, of both elderly themselves and their children, had influence on the elderly's dating experience, regardless of gender. This indicates that the elderly's own acceptance and their children's positive attitude are important to the elderly's dating experience. 3. Gender differences were found in influences of living arrangement (whether they lived with their children or not), economical reasons, and personality factors. These variables proved significant only for the elderly men. More elderly men who did not live with their children than the elderly men who did had experienced dating, and economical reasons along with personality factors proved to be obstructive for elderly men's dating life.

A Study on Autistic Children in Korea (우리나라의 기관등록 자폐아에 관한 연구)

  • 이영자
    • Journal of Korean Academy of Nursing
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    • v.20 no.2
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    • pp.142-152
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    • 1990
  • This Study was to determine the trend of child rearing attitude, to investigate how variables affect the child rearing attitudes, and to suggest directions for developing much needed parental effective training programs or counselling for autistic child in community. The subjects were seventy six mother's of autistic children who attending to 13 treatment institutions in Korea. The data were collected from 1, March to 30, May, 1985. Maternal Behavior Research Instrument exploited by Schaefer, used as 3 tool in this study. The research findings obtained were as follows : 1. Mothers, in general, had affective, restrictive attitudes, and were found to be affective, yet did not give a positive evaluation of children's behavior and used fear control extensively, thus made their children dependent. 2. There were no significant differences in child rearing attitude by children's sex and age. 3. There were no significant differences in child rearing attitudes by mother's age, education level and religion. 4. There was no significant difference in child rearing attitudes by father's occupation.

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Varietal Difference of Sucker producing Characteristics in Burley Tobacco(Nicotiana tabacum L. var. burley) (버어리종 연초 곁순발생의 품종간 차이)

  • 정석훈;조천준;최상주;조명조;백종운
    • Journal of the Korean Society of Tobacco Science
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    • v.22 no.1
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    • pp.39-44
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    • 2000
  • This study was carried out to obtain the basic information about the sucker producing characteristics of certain burley tobacco varieties(Nicotiana tabacum L. var. burley) at Suwon and Chonju Experiment Station, Korea Ginseng & Tobacco Research Institute in 1999. The number and weight of suckers for 12 varieties or breeding lines were investigated three times, 45 days after transplanting for ground sucker, 10 days after topping, and 10 days after maleic hydrazide(MH) applying for upstalk sucker. KB 103 and KB 9416-1 produced less ground suckers and upstalk suckers than other entries did. KB 9210-8 produced less ground suckers and (Male sterile TC 612 x KB 108)F$_1$ also produced less upstalk suckers than other entries did. There was no differences among entries in sucker production at 10 days after MH treatment. Between the weight of total sucker and days to flower revealed the negative correlation, but not significant. The low sucker producing entries described above could be used as a parental line in the breeding program for the low sucker producing variety.

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Quality Characteristics of Kimchi with Added Houttuynia cordata (어성초를 첨가한 김치의 품질 특성)

  • Kwak, Hee-Jung;Jang, Jae-Seon;Kim, Soon-Mi
    • The Korean Journal of Food And Nutrition
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    • v.22 no.3
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    • pp.332-337
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    • 2009
  • This study was performed to investigate the physiochemical and sensory characteristics of Kimchi with added Houttuynia cordata Thunb(HC). According to measurements for physicochemical characteristics, the three groups of tested Kimchi(HC juice, HC powder, control) did not show any significant differences in pH and hardness. However, the acidity of the Kimchi with added HC juice was found to be significantly higher. Regarding lightness, L values were not different among the three groups, while a and b values showed significant decreases. In descriptive analysis, Kimchi redness was lowest in the HC juice group, and difference in redness was identified between the HC juice and powder groups. One survey indicated that the Kimchi with added HC juice had a unique odor, but no difference was found between the HC powder group and the control group. Also, a survey on preference characteristics indicated there were no differences between the three groups. For the saltiness and acidity of the Kimchi with added HC, there was a significant negative correlation(p<0.05), in which stronger saltiness lower acidity. On the other hand, acidity and HC odor showed a significantly positive correlation(p<0.05). Furthermore, the L value showed a significantly negative correlation(p<0.05) with HC odor.

Infection control awareness and practice for clothing management in 119 emergency medical technicians (구급대원의 의복관리를 위한 감염관리 인지도와 수행도)

  • Jeong, Ji-Yeon;Jeong, Eun-Kyung;Yun, Hyeong-Wan
    • The Korean Journal of Emergency Medical Services
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    • v.18 no.2
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    • pp.21-33
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    • 2014
  • Purpose: A descriptive study design was used to investigate infection management awareness and infection management performance for clothing management in 119 emergency medical technicians (EMTs). Method: 188 paramedics and basic EMTs completed questionnaires between March 1 and April 30, 2013 in Jeollabuk-do. Results: Participants' average score for infection control awareness was 2.69 and that for performance was 1.58, with the differences being statistically significant (t = 931.455, p = .003). Participants' general characteristics resulted in differences in infection management performance. Women (1.63) have scored higher than men (1.28), and the difference was statistically significant (t = 11.174, p = .001). Participants who had clinical experience (1.63) had higher scores than participants who did have clinical experience before (1.53) and, again, the difference was significant (t = 7.167, p = .009). Conclusion: Education program for infection management is need to be developed for more effective infection management.

Differences in Life Transition Process of Parents Caring for Children with Autism: Based on the Socio-Demographic Characteristics (자폐성 장애 자녀를 양육하는 부모의 삶의 전환과정의 차이: 인구사회학적 특성을 중심으로)

  • Lee, Ae Ran;Hong, Sun Woo
    • Child Health Nursing Research
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    • v.21 no.4
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    • pp.331-338
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    • 2015
  • Purpose: This study was done to identify differences in the life transition process of parents caring for children with autism according to parents' socio-demographic characteristics. Methods: Participants were 194 parents caring for children with autism. Data were collected from December 2013 to February 2014 through self-report questionnaires, and analyzed using descriptive statistics, t-test, ANOVA with SPSS/WIN 20.0. Results: Mean scores for despairing or accepting phases were higher than those for denying or wandering phases in the life transition process. According to parents' gender, educational level, and job, there were some significant differences in the denying and wandering phases. Differences in denying phase by education (p=.033), job (p=.004) were significant. Respondents with higher educational level, and having a job showed a lower level of denying than other respondents. Wandering phase differed significantly by gender (p=.009) and job (p=.001). Mothers and those who did not have a job showed a higher level of wandering than fathers and those who had a job. However, there was no difference in the despairing or accepting phases. Conclusion: The life transition phase of parents with autistic children needs to be assessed to provide differentiated and intensive support program and help them move to the accepting phase.

A Study on the physicochemical Properties and Palatability of Hanwoo Beef Loin in $1^+$ Grade (한우 $1^+$ 등급육의 이화학적 특성과 기호성에 관한 연구)

  • 문윤희;김미숙;김대진;양종범;강세주
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.6
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    • pp.1288-1292
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    • 1999
  • The physicochemical properties and palatability of Hanwoo(cow, steer, and bull) beef loin(1+ carcass grade) were studied. pH(5.56~5.69), moisture content(67.6~69.0%), crude protein content(17.8~18.7%), and crude fat content(11.9~13.8%) of Hanwoo beef loin did not show significant difference between the types of Hanwoo. L(44.5~46.9), a(19.9~20.6), and b(10.3~11.6) color parameters, water holding capacity (69.4~70.5%), volatile basic nitrogen content(9.86~11.28mg%), thiobarbituric acid value(0.148~0.158 mg malonaldehyde/kg), and cooking loss(26.3~27.9%) of beef loin did not show significant difference between the types of Hanwoo either. Hardness, myofibrillar fragmentation index(MFI), and chewiness of beef loin were 6.1~6.9 dyne/cm2, 50.3~54.9, and 39.5~ 52.0g, respectively. No differences were found in hardness and MFI between the types of Hanwoo, while chewiness of cow was much lower than that of steer and bull(p<0.05). Cow was the best in palatability.

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STUDIES ON THE CLINICAL EFFICACY OF VALIUM AND PENTOBARBITAL AS PREMEDICATING AGENT (준비투약(準備投藥)으로서 Valium, Pentobarbital의 임상적(臨床的) 효과(效果)에 관(關)한 연구(硏究))

  • Kim, Young-Jin
    • Journal of the korean academy of Pediatric Dentistry
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    • v.5 no.1
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    • pp.76-82
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    • 1978
  • To evaluate clinically effect of Valium and Sodium pentobarbital as premedicating agent, both drugs and a placebo were compared in 45 patients (2 to 11 yrs). The results were as follows. 1. Both Sodium pentobarbital and Valium were superior to placebo for control of crying, cooperation and apprehension, but the statistically differences were not significant. 2. Both Valium and Sodium pentobarbital were superior to placebo for control of behavior in tense cooperative child; the differences were significant statistically. 3. The difference between Pentobarbital and Valium were-more pronounced at the initial level than at the subsequent readings, and Sodium pentobarbital was for superior at the initial level to the other drugs. 4. Paradoxical excitement occured in 2 cases on the Sodium pentobarbital group, and other apparent side effect did not occur, excluding mild drowsiness. 5. Neither Valium nor Sodium pentobarbital, as used in this study, resulted in consistantly better behavior in all patients.

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Analysis of Good College Teaching Characteristics by multi-faceted approach (다면적 접근을 통한 대학의 좋은 수업 특성 분석)

  • Yune, So-Jung
    • Journal of Fisheries and Marine Sciences Education
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    • v.24 no.6
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    • pp.963-976
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    • 2012
  • As the college environment changes, the roles of professors and students should also be changed. And the way that we teach undergraduate students should also be changed. The purpose of this research is to analysis characteristics of good teaching methods in college as perceived by students and professors. We did content analysis to elicit the characteristics of good instruction from qualitative comments of 196 course evaluations, 195 excellent essays selected from 8 college essay competitions, and 72 teaching knowhow essays of professors. To see the difference of division in good instruction characteristics, we did frequency analysis by SPSS statistics program. According to the content analysis, the most essential characteristics of good instruction as perceived by the students and professors is teaching strategies. There were also differences in the fact of recognition transition by division and the students-professors.