• 제목/요약/키워드: null test

검색결과 276건 처리시간 0.026초

대학입학유형이 대학생활적응과 학업성취도에 미치는 영향 - 일개 대학 간호학과 학생을 대상으로 (A Study on the Relationship Between College Adaptation, Academic Achievement, and Admission Type in One Nursing School)

  • 한미현;배상목
    • 한국간호교육학회지
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    • 제21권1호
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    • pp.46-53
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    • 2015
  • Purpose: This study was performed to identify the effect of admission type on college adaptation and academic achievement in one nursing school in order to refine the entrance selection system. Methods: Subjects were 405 nursing students (female : male = 385 : 20, first grade = 155, second grade = 138, third grade = 112). They were given the Student Adaptation to College Questionnaire (SACQ) purchased from Western Psychological Service. SACQ is composed of 67 questions and subdivided into 4 subcategories: academic adjustment, social adjustment, personal-emotional adjustment, and attachment. Student college adaptation scores and academic achievements were analyzed with reference to the entrance selection system (rolling admission vs. regular admission) by SPSS 22.0. The rolling admission system recruited students based on high school records only while the regular admission system was based on both high school records and the College Scholastic Ability Test (CSAT). Results: Total College adaptation score, personal-emotional adjustment score, and academic achievement were higher in regular-admission students than in those admitted through rolling admission. Academic achievement for first-grade students was higher in regular-admission students than for those admitted through rolling admission, But the difference in academic achievement became null as students were promoted to the second and third grades. Conclusion: Students recruited using both high school records and the CSAT showed better college adaptation and higher academic achievement.

한.ASEAN FTA가 광양항 수출에 미치는 영향: 패널중력모형과 전향적 이동회귀의 적용 (Effects of Korea-ASEAN FTA on Export via Gwangyang Port: Application of the Panel Gravity Model and Rolling Regression)

  • 박홍균;김창범
    • 한국항만경제학회지
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    • 제30권2호
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    • pp.133-143
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    • 2014
  • 우리나라는 주요 선진국들이 지역주의를 확산시키고, FTA 체결 회원국 전체의 경제적 부가가치를 증대시킬 수 있다는 점에서 FTA를 적극적으로 추진하고 있다. 우리나라의 현재 FTA 추진 현황은 발효 9건, 타결 3건, 협상진행 6건, 협상재개 여건조성 3건, 협상준비(공동연구 포함) 4건으로, 한 중 FTA이 체결된다면 우리나라의 FTA 교역 비중은 조만간 전체 교역의 50%를 넘어설 것으로 예상된다. 그리고 우리나라 무역의 대부분이 해상을 통해서 이루어짐을 감안할 때 항만을 통한 무역패턴과 수출효과를 파악할 필요가 있다. 최근에는 전통적인 교역이론에서 고려되지 않았던 거리적 위치, 운송비용, 인구 수, 문화적 요인이 교역패턴에 영향을 미친다는 중력모형의 적용이 많이 늘어나고 있다. 이러한 배경 하에서 본고는 패널중력모형을 이용하여 광양항의 주요 교역 상대국의 수출결정요인을 식별하고, FTA가 광양항 수출에 미치는 영향의 크기를 분석하였다. 분석결과, 패널 수준변수들은 불안정적이고 1차 차분 후 안정성을 회복하였다. 다음 단계로 패널 공적분 검정을 통해 패널 수준변수들의 장기적 균형 관계가 존재함을 알 수 있었으며, 하우스만 검정을 통하여 고정효과 모형이 적합함을 밝힐 수 있었다. 패널중력모형 분석결과, 중력모형의 기본전제가 양호하게 성립하고, 지역무역협정의 수출증대 효과가 존재하는 것을 확인할 수 있었다.

액체와 Digital Holographic Microscopy을 이용한 비구면 렌즈 측정 연구 (Aspheric Lens Measurements by Digital Holographic Microscopy and Liquid)

  • 김두철;신상훈;유영훈
    • 한국광학회지
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    • 제24권6호
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    • pp.318-323
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    • 2013
  • 디지털 홀로그래피 현미경은 기준광과 시료의 굴절률과 두께에 의한 광경로 차이를 간섭 방법을 이용하여 측정하여 3차원 형상을 측정하는 방법이다. 그리고 광 경로차는 시료의 두께와 시료와 시료 주변의 굴절률 차이에 의존한다. 시료 형상 기울기가 매우 큰 경우에는 광 경로차가 커져 일반적인 간섭 방법으로는 측정이 어렵다. 이런 경우 시료를 액체에 담그어 측정하면 광 경로차가 매우 작아져서 일반적인 간섭 방법을 이용하여 측정할 수 있다. 본 연구에서는 디지털 홀로그램 현미경과 액체를 이용하여 기울기가 큰 비구면 렌즈의 형상을 측정하는 연구를 하였다. 시료의 굴절률과 비슷한 액체를 선택함으로서 비구면 렌즈의 정밀한 3차원 측정이 가능하였다.

인산축적 뽕밭의 인산 감량시비에 관한 연구 (Reduction of Phosphorus Fertilizer in Mulberry Fields, High in Phosphate)

  • 이원주;최영철
    • 한국잠사곤충학회지
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    • 제35권1호
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    • pp.11-16
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    • 1993
  • 인산이 축적된 뽕밭에서 인산 시비량을 조절하기 위하여, 유효인산 300ppm 정도 포장 2개소, 450 ppm정도 포장 1개소에서 인산 표준시비량구(13kg/10a), 반량구, 무인산구, 무시비구 등을 설정하여 4년동안의 포장시험과 엽질검정을 위한 누에 사육시험을 3년동안 수행한 결과 다음과 같았다. 1. 토양유효인산 함량이 450ppm포장에서는 4년간 계속된 인산 무시비구에서도 뽕잎 수량감소가 없었으나, 300ppm포장에서의 무인산구에서는 3년차 봄부터, 인산 반량구에서는 4년차 가을부터 감수가 시작되었다. 2. 연차별로 토양 인산의 감소에 따른 수량감소와의 관계에 의하여 인산시비 개시 시기를 조사한 결과, 토심 10~20cm 부위에서 유효인산의 함량이 150ppm 이하로 떨어졌을 때 인산시비를 개시하는 것이 적당한 것으로 나타났다. 3. 인산 감량시비에 따른 뽕잎 중의 인산함량은 표준량 시비구 대비 0.18%까지 감소하였다. 4. 인산의 감량시비가 뽕잎의 질에 미치는 영향을 알기 위하여 3년간 토양인산 300ppm 포장의 뽕잎으로 누에를 사육하여 검정한 결과, 인산 무시비에 의해 수량이 감소하고, 엽중의 인산 함량이 최저 1.13%까지 감소하였어도, 수견량 및 견질에는 영향을 주지 않았다.

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효모에서 SHC1 유전자의 이온 농도 조절에 의한 세포내 pH 항상성 유지 (Regulation of Intracellular pH by SHC1 in Saccharomyces cerevisiae)

  • 하승길;전준철;최의열
    • 미생물학회지
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    • 제38권3호
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    • pp.168-172
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    • 2002
  • 출아효모는 주변 환경 pH의 커다란 변화 속에서 적응할 수 있는 효과적인 체계를 지니고 있으며 SHC1 유전자는 알칼리 pH 조건에서 세포의 성장에 필요한 유전자 중에 하나임을 확인하였다. SHC1 유전자의 세포내 pH 조절 기작을 보다 구체적으로 알아보기 위하여 이 유전자가 소실된 돌연변이주를 제조하였다. 성장률의 차이가 나타나는 원인을 세포 내부의 pH 완충능력 결여에 의한 것으로 추측하고 pH 감수성 형광물질인 C.SNARE를 사용하여 외부 pH의 변화에 따른 세포 내부의 pH를 측정하였다. 알칼리 pH 완충효과는 소실 돌연변이의 경우는 야생종 대비 70% 수준을 보였다. 또한 pH 조절에 관여하는 효모세포 내부의 $Na^{+}$$K^{+}$의 농도를 원자흡광계를 사용하여 조사한 바, $K^{+}$ 이온의 경우에는 돌연변이주에 비하여 야생형 세포내에 더 많이 존재하는 것으로 나타났으나 $Na^{+}$ 이온의 경우는 별다른 차이점을 보이지 않았다. 이러한 결과는 $K^{+}$ 이온의 조절이 효모에서 세포내 pH조절 기작에 중요하며 SHC1 유전자는 이 $K^{+}$ 이온의 세포내 농도 유지에 관여하고 있다는 것을 제시해 주었다.

병원중심 가정간호 사업의 평가 연구 -외래 관절염 환자를 대상으로 - (Effects of Hospital-based Home Care Demonstration Project on Physical and Emotional Problems and Cost - effectiveness of Patients having Arthritis)

  • 임난영;김성윤;이은옥;이인숙
    • 근관절건강학회지
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    • 제3권1호
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    • pp.4-22
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    • 1996
  • Purposes of this study were to identify a hospital-based home care model and to improve the physical, emotional and economical effectiveness of arthritic patients through medical and nursing team approach. The design in nonequivalent control group pretest-posttest design with matched samples in terms of age, sex and disease severity. Fifty two patients in each group were assigned in Seoul, Kyunggi, Kangwon and Kwangju. Before and after 6-month period of home care, level of pain, duration of morning stiffness, Richie Index, ADL, self efficacy, depression, cost expenditure were measured. Nine patients were excluded from the control group in the period of study because of denial of participation. Contents of home care provided to the experimental group include mainly distribution of prescribed drugs, 'assessment of patients' condition and side-reactions of drug. All of the information related to the home care patient were reported to the physician. On the bases of these data, the physician prescribe the specific drugs to each patient. Each patient visited the physician every 2 or 3 month for laboratory test. Patients assigned to the control group visited the outpatient clinic once a month as usual. Null hypotheses were selected because physicians concerned about the ineffective change of patients' conditions due to indirect communication with patients through nurses. Level of pain, Richie index, ADL, self-efficacy, depression, duration of morning stiffness and direct medical cost were the home care provided to them. If a family member accompany in a home care group can save 10,676 Won/month in Seoul, 34,000 Won/month in other districts. Other in-direct cost for transportation and meal can also be saved. In conclusion, those patients with low level of ADL, high level of pain and Richie index, living in the remote area definitely need the home care.

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Genetic parameters and correlations of related feed efficiency, growth, and carcass traits in Hanwoo beef cattle

  • Mehrban, Hossein;Naserkheil, Masoumeh;Lee, Deuk Hwan;Ibanez-Escriche, Noelia
    • Animal Bioscience
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    • 제34권5호
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    • pp.824-832
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    • 2021
  • Objective: This study aimed to estimate the genetic parameters and genetic correlations for related feed efficiency, growth, and carcass traits in Hanwoo cattle. Methods: Phenotypic data from 15,279 animals born between 1989 and 2015 were considered. The related feed efficiency traits considered were Kleiber ratio (KR) and relative growth rate (RGR). Carcass traits analyzed were backfat thickness (BT), carcass weight, eye muscle area, and marbling score. Growth traits were assessed by the average daily gain (ADG), metabolic body weight (MBW) at mid-test age from 6 to 24 months, and yearling weight (YW). Variance and covariance components were estimated using restricted maximum likelihood using nine multi-trait animal models. Results: The heritability estimates for related feed efficiency (0.28±0.04 for KR and RGR) and growth traits (0.26±0.02 to 0.33±0.04) were moderate, but the carcass traits tended to be higher (0.38±0.04 to 0.61±0.06). The related feed efficiency traits were positively genetically correlated with all the carcass traits (0.37±0.09 to 0.47±0.07 for KR, and 0.14±0.09 to 0.37±0.09 for RGR), except for BT, which showed null to weak correlation. Conversely, the genetic correlations of RGR with MBW (-0.36±0.08) and YW (-0.30±0.08) were negative, and those of KR with MBW and YW were close to zero, whereas the genetic correlations of ADG with RGR (0.40±0.08) and KR (0.70±0.05) were positive and relatively moderate to high. The genetic (0.92±0.02) correlations between KR and RGR were very high. Conclusion: Sufficient genetic variability and heritability were observed for traits of interest. Moreover, the inclusion of KR and/or RGR in Hanwoo cattle breeding programs could improve the feed efficiency without producing any unfavorable effects on the carcass traits.

청소년 배드민턴 선수의 경기력 수준과 성취목표성향의 관계 (Relationship between the Performance Level and Achievement Goal Orientation on Youth Badminton Players)

  • 김덕진
    • 문화기술의 융합
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    • 제7권1호
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    • pp.364-368
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    • 2021
  • 본 연구는 대한민국 청소년 배드민턴 국가대표 선수를 대상으로 그들의 경기력과 성취목표성향의 하위 요인인 자아성향과 과제성향에 어떤 관계가 있는지 알아보고자 수행되었다. 이에 배드민턴 청소년 대표 선수들의 경기력 수준에 따라 자아성향과 과제성향은 차이가 없을 것이라는 두 개의 영가설을 설정하고 이를 검증하고자 하였다. 연구대상으로는 2018년도 청소년 배드민턴 국가대표 하계 합숙훈련에 소집된 중,고등학생 92명으로 하였고, 이들의 학교급별 단식 전체리그 결과를 토대로 하여 경기력 상,하 집단으로 구분하여 자아성향과 과제성향의 차이를 각각 알아보았다. 검사도구로는 스포츠 성취목표지향성에 관한 검사지(Task & Ego Orientation in Sport Questionnaire, TEOSQ)를 사용하였다. 자료의 경향을 파악하기 위해서 빈도분석을 실시하였고 검사지의 신뢰도를 알아보기 위해서 신뢰도 분석(Cronbach's α)을 실시하였으며 마지막으로 경기력 집단 간 성취목표성향의 차이를 알아보기 위하여 독립 t검증을 실시하였다. 그 결과, 경기력 상집단과 하집단 간에 자아성향과 과제성향 두 요인 모두 통계적으로 유의한 차이가 나타나지 않았다. 연구결과를 토대로 논의하였다.

Icevaning control of an Arctic offshore vessel and its experimental validation

  • Kim, Young-Shik;Kim, Jinwhan
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제13권1호
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    • pp.208-222
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    • 2021
  • Managing with the presence of sea ice is the primary challenge in the operation of floating platforms in the Arctic region. It is widely accepted that offshore structures operating in Arctic conditions need station-keeping methods as well as ice management by icebreakers. Dynamic Positioning (DP) is one of the station-keeping methods that can provide mobility and flexibility in marine operations. The presence of sea ice generates complex external forces and moments acting on the vessel, which need to be counteracted by the DP system. In this paper, an icevaning control algorithm is proposed that enables Arctic offshore vessels to perform DP operations. The proposed icevaning control enables each vessel to be oriented toward the direction of the mean environmental force induced by ice drifting so as to improve the operational safety and reduce the overall thruster power consumption by having minimum external disturbances naturally. A mathematical model of an Arctic offshore vessel is summarized for the development of the new icevaning control algorithm. To determine the icevaning action of the Arctic offshore vessel without any measurements and estimation of ice conditions including ice drift, task and null space are defined in the vessel model, and the control law is formulated in the task space. A backstepping technique is utilized to handle the nonlinearity of the Arctic offshore vessel's dynamic model, and the Lyapunov stability theory is applied to guarantee the stability of the proposed icevaning control algorithm. Experiments are conducted in the ice tank of the Korea Research Institute of Ships and Ocean Engineering to demonstrate the feasibility of the proposed approach.

산업폐기물 소각장 근로자에서 요중 PAHs 대사산물과 혈중 aromatic-DNA adducts (Association of PAH-DNA adducts and Urinary PAH metabolites influenced by polymorphisms of xenobiotic metabolism enzymes in industrial wase incinerating workers)

  • 이경호;;최인미;최재욱;조수헌;강대희
    • 한국환경성돌연변이발암원학회지
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    • 제22권4호
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    • pp.303-311
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    • 2002
  • This study evaluated the concentrations of urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) in industrial waste incineration workers. The effect of genetic polymorphisms of xenobiotic metabolism enzymes on urinary concentration of PAH metabolites was assessed. And, aromatic DNA adduct levels were also determined in total white blood cells. Fifty employees were recruited from a company handling industrial wastes located in Ansan, Korea: non-exposed group (n=21), exposed group (n=29). Sixteen ambient PAHs were determined by GC/MSD (NIOSH method) from personal breathing zone samples of nine subjects near incinerators. Urinary 1-hydroxypyrene glucuronide (1-OHPG), a major pyrene metabolite, was assayed by synchronous fluorescence spectroscopy after immunoaffinity purification using monoclonal antibody 8E11 (SFS/IAC). Multiplex PCR was used for genotyping for GSTMI/TI and PCR-RFLP for genotyping of CYP1A1 (MspI and Ile/Val). PAH-DNA adducts in peripheral blood WBC were measured by the nuclease P1-enhanced postlabeling assay. Smoking habit, demographic and occupational information were collected by self-administered questionnaire. The range of total ambient PAH levels were 0.00-7.00 mg/㎥ (mean 3.31). Urinary 1-OHPG levels were significantly higher in workers handling industrial wastes than in those with presumed lower exposure to PAHs (p=0.006, by Kruskal-Wallis test). There was a statistically significant dose-response increase in 1-OHPG levels with the number of cigarettes consumed per day (Pearson correlation coefficient=0.686, p<0.001). Urinary 1-OHPG levels in occupationally exposed smoking workers were highest compared with non-occupationally exposed smokers (p=0.053, by Kruskal-Wallis test). Smoking and GSTMI genotype were significant predictors for log-transformed 1-OHPG by multiple regression analysis (overall model R²=0.565, p<0.001), whereas smoking was the only significant predictor for log-transformed aromatic DNA adducts (overall model R²=0.249, p=0.201). Aromatic DNA adducts was also a significantly correlation between log transferred urinary 1-OHPG levels (pearson's correlation coefficient=0.307, p=0.04). However, the partial correlation coefficient adjusting for Age, Sex, and cigarette consumption was not significant (r=0.154, p=0.169). The significant association exists only in individuals with the GSTMI null genotype (pearsons correlation coefficient=0.516, p=0.010; partial correlation coefficient adjusting for age, sex, and cigarette consumption, r=0.363, p=0.038). Our results suggest that the significant increase in urinary 1-OHPG in the exposed workers is due to higher prevalence of smokers among them, and that the association between urinary PAH metabolites and aromatic DNA adducts in workers of industrial waste handling may be modulated by GSTMI genotype. There results remain to be confirmed in future larger studies.

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