• Title/Summary/Keyword: Sample orientation

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Determination of Granitic Core Orientation Using Healed Microcracks (아문 미세균열을 이용한 화강암 시추코아의 방향 결정에 관한 연구)

  • 장보안;김영화
    • The Journal of Engineering Geology
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    • v.7 no.2
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    • pp.151-159
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    • 1997
  • Since healed microcracks in quartz grain of grantic rocks within the same mass have identical preferred orientations, the oreintations of granitic cores may be determined if the distinctive feature of healed microcracks can be used.In this study, the possibility of determining orientations of granitic cores using healed microcrack orientations were examined using samples from the borehole drilled to 200 m in depth at the Hongcheon. Eight sections whose core recoveries are 100% were selected. Two to six samples were collected in each section and orientations of healed microcracks in each sample were measured. Healed microcracks in samples from each section show almost identical orientations. The error range for sections with only one preferred orientations is within $\pm$5$^{\circ}$, indicating that correct orientations of core can be determined. However, orientations of cores in sections which have 2 or more healed microcrack orientations should be determined using orientations as well as distribution of peaks of orientations. The error range for this case is lager than former one and is within $\pm$15$^{\circ}$. The orientations of joint which is very impontant factor for designing tunnel and slope stability can be determined using healed microcrack orientation in cores.

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Investigation of Fracture Propagation in Cement by Hydraulic Fracturing Under the Tri-axial Stress Condition (시멘트 시료에 대한 삼축압축 환경에서의 수압파쇄시험 연구)

  • Riu, Hee-Sung;Jang, Hyun-Sic;Jang, Bo-An
    • The Journal of Engineering Geology
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    • v.27 no.3
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    • pp.233-244
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    • 2017
  • We conducted hydraulic fracturing experiments on cement samples to investigate the dependency of fracture propagation on the viscosity of injection fluid and the in situ stress state. Ten cubic samples (20 cm side length) were produced using cement that was cured in water for more than one month. Samples were placed in a tri-axial compression apparatus with three independent principal stresses. An injection hole was drilled and the sample was hydraulically fractured under a constant injection rate. We measured injection pressures and acoustic emissions (AE) during the experiments, and investigated the fracture patterns produced by hydraulic fracturing. Breakdown pressures increased exponentially with increasing viscosity of the injection fluid. Fracture patterns were dependent on differential stress (i.e., the difference between the major and minor principal stresses). At low differential stress, multiple fractures oriented sub-parallel to the major principal stress axis propagated from the injection hole, and in some samples the fracture orientation changed during propagation. However, at high differential stress, a single fracture propagated parallel to the major principal stress axis. AE results show similar patterns. At low differential stress, AE source locations were more widespread than at high differential stress, consistent with the fracture pattern results. Our study suggests that hydraulic fracturing during shale gas extraction should be performed parallel to the orientation of minimum differential stress.

University Students' Starts-up Intention and Its Antecedents: Focusing on Entrepreneurship Education for Freshman Orientation (대학생의 창업의도에 미치는 영향요인에 대한 연구: 신입생 Orientation 기업가정신 교육을 중심으로)

  • Yu, Jum Suk;Suh, Chang Soo;Yu, Yon Ho;Kim, Young Soo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.11 no.5
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    • pp.91-104
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    • 2016
  • The major results of the study are as follows: First, the accomplishement needs and academic self-efficacy enables students with start-up education through studying immersion and entrepreneurship to set up realistic objectives for personal life and resolving unpredictable problems. Second, creativity does not significantly affect studying immersion, but the higher the creativity of students participating in start-up education, the higher the entrepreneurship compare to studying immersion. Third, studying immersion has a significant impact on entrepreneurship, but has less impact on student's intention for start-up. Students with higher studying immersion through start-up education has higher entrepreneurship spirit and as a result, higher intention for start-up. Finally, the limitation of the study was that the sample was taken only from the freshman of Soonchunhyang University. Therefore, further study is needed for students from all university with start-up education.

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A Study on the Perception of the Importance and Performance of Patient Education of the Clinical Nurses (종합병원 간호사가 인식하는 환자교육 중요도와 수행도의 관계연구)

  • Yoo, Eun-Kyung;Suh, Moon-Ja
    • The Journal of Korean Academic Society of Nursing Education
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    • v.6 no.2
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    • pp.287-302
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    • 2000
  • The purpose of the study are to examine the perception of the importance and performance of patient education of the clinical nurse and find out the interfering factors in practicing patient education. The data were collected from convenient sample of 256 clinical nurses working in the nursing units of adult patients except the psychiatric unit, obstetric unit, dental surgical unit and intensive care unit of one University Hospital in Seoul from September 29 to October 2, 1998. Three measurement tools of self-report- questionnaires developed by researcher used. For the content validity of the questionnaires, two sessions of panel discussion and a pilot test were done and finally factor analysis was done with Varimax method. Analysis of data was done with SAS program using frequency, percentage, means, standard deviation, Pearson's Correlation Coefficients, t-test and ANOVA. The obtained results were as follows : 1. The surveyed nurses perceived the importance of patient education at higher level with mean score of 4.08 among 5 point than their perception of practice( mean score : 3.42). 2. There was positive significant correlation(r=.29, p=0.0001)between nurses' perception of the importance of patient education and it's practice 3. Among the teaching contents for patients, 'information of diagnostic procedure and operation' and 'orientation of hospitalization' were perceived most important. And 'preparation for discharge' and 'understanding of disease and health promotion' were perceived least important 4. Among the teaching contents for patients, 'orientation of hospitalization' and 'information of diagnostic procedure and operation' were perceived highly performable. And 'understanding of disease and health promotion' and 'preparation for discharge' were perceived least performable. 5. Three types of interfering factors were identified as patient-factor, situational factor, nurse-factor. The mean degree of impediment with the interfering factors was at average level(3.09 among 5). The patient and situational factors of impediments were more interfering than nurse- factor for teaching patients. 6. In older age(p<.05), married state (p<.05), higher educational status (p<.01), higher clinical experience (p<.01) and higher position(p<.01), the score of perceived importance of patients education was more high. 7. In older age(p<.01), higher clinical experience(p<.001) and surgical unit (p<.01), the score of perceived performance of patients education was more high. In conclusion, in order to activate patient education practice in the clinical setting, the continuing education for patients education should be more emphasized and the effective teaching methods and materials should be developed to help patient teaching. And an organizational support such as budgeting for patient education and reimbursement system should be administrated.

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Perceived Enactment of Ethnic Socialization by Japanese Marriage Migrant Mothers of 7- to 18-Year-Old Children (일본 출신 결혼이주여성이 인지하는 자녀에 대한 민족사회화 수행 : 만 7-18세 자녀를 중심으로)

  • Yoon, Soohyun;Chung, Grace H.
    • Journal of Families and Better Life
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    • v.33 no.3
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    • pp.15-29
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    • 2015
  • The purpose of this study was to explore ethnic socialization enacted by Japanese marriage migrant women currently raising 7- to 18-year-old children in Korea. To accomplish this goal, we examined the following research questions: (1) What is the level of ethnic socialization enacted by Japanese marriage migrant mothers? (2) Does the level of ethnic socialization vary by demographic and ethnocultural factors? (3) To what extent do demographic and ethnocultural factors influence the enactment of ethnic socialization by Japanese marriage migrant mothers? The sample consisted of 243 Japanese marriage migrant women currently raising 7- to 18-year-old children in Korea. For data analysis, T-test, correlation, ANOVA, and hierarchical regression analyses were used. Also, we performed separate analyses for two subtypes of ethnic socialization in particular, namely cultural socialization and preparation for bias. Ethnocultural factors examined in this study were the level of discrimination experience, Japanese ethnic identity, and husbands' ethnic orientation in childrearing. The main results of this study were as follows. First, results showed that Japanese marriage migrant women enacted moderate levels of cultural socialization and preparation for bias. Second, Japanese marriage migrant women's cultural socialization and preparation for bias were both positively related to the levels of women's discrimination experience and Japanese ethnic identity. Also, the younger the age of the firstborn child, the more preparation for bias these women performed. In addition, women whose Korean husbands wanted to raise their children more biculturally performed more cultural socialization compared to those with Korean husbands who wanted to raise their children as Korean. Third, hierarchical regression analyses revealed that women's discrimination experience and ethnic identity positively predicted both types of ethnic socialization. Also, Korean husband's bicultural orientation towards childrearing predicted a higher level of cultural socialization by Japanese marriage migrant women. Results of this study provide basic information about ethnic socialization among multicultural families in Korea, which can be useful for promoting positive self-identity among multicultural children. Furthermore, the results suggest that husbands' support and cooperation in ethnic socialization can be crucial for marriage migrant women to socialize their children utilizing their cultural and experiential resources.

Affects on Implementation Level of IMS Activity and Performance according to IMS directivity and Fitness of Firm's Culture (IMS지향성과 기업문화 적합도가 IMS활동의 이행수준과 성과에 미치는 영향)

  • Kim, Kyung-Ihl
    • Journal of Convergence Society for SMB
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    • v.1 no.1
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    • pp.1-8
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    • 2011
  • With a sample of 147 Korean small and medium size companies, this study examined the relationships among degree of information orientation, corporate culture, degree of information management implementation and selected business performances in the process of implementing IMS(Information Management System). Information orientation is defined as company-wide understanding and implementation of the underlying philosophy, principles, approached, and tools of information improvement programs. It is assumed that successful implementation of information improvement programs requires a information-oriented mind-set of the employees. It is also assumed that successful implementation of information improvement programs require strong support from s corporate culture that emphasizes continues improvement. Adopting the competing values model of Quinn and McGrath(1985), corporate culture is classified into 'flexible' versus 'controlled culture' and 'outer-directed' versus 'inner-directed culture'. This study examined how such fitness influenced the implementation of information innovation programs and business performance. Implementation of information innovation programs was measured through various factors, such as leadership, strategic information planning, human resources focus, customer and market focus, process management, and information analysis and application. Business performance was measured through non-financial performance measuresm such as employee results, process results, information results, and customer results, and through perceived financial performance measures.

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Magnetic properties and the shapes of magnetic domain for $CoCr_{16.2}Pt_{10.8}Ta_4$ alloy films with the prior deposition of Ti layer ($CoCr_{16.2}Pt_{10.8}Ta_4$ 합금박막의 Ti 우선증착에 따른 자기적 특성과 자구형상변화)

  • 이인선;김동원
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.10 no.1
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    • pp.17-22
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    • 2000
  • A quaternary alloy film of $CoCr_{16.2}Pt_{10.8}Ta_4$was investigated for its magnetic properties and c-axis orientation with and without Ti underlayer. Additional elements such as Ta, Pt have been frequently introduced in CoCr alloy film for perpendicular recording as a means of improving magnetic performance. It has been reported that the addition of Pt and Ta in CoCr increase the coercivity and the magnetic isolation of columnar grains, respectively. However, CoCrPtTa perpendicular magnetic layer should be more increased its perpendicular magnetic anisotropy than at present for the application of ultrahigh recording density. The improvement of underlayers and substrate materials is one of the promised schemes to intensify the perpendicular magnetic anisotropy. In this study, the insertion of Ti underlayer shows the remarkable improvement of c-axis orientation compare with the direct deposition on the bare glass. The mechanism about this effect of Ti underlayer on CoCrPtTa is not to be clarified yet. Meanwhile, it is found that the magnetic domain of CoCrPtTa on 20 nm Ti underlayer has the continuous stripe pattern but the one of CoCrPtTa on 90 nm Ti underlayer shows the discrete mass type from the results of MFM investigation. This phenomenon is to be a distinct evidence that the improvement of perpendicular anisotropy by the adoption of Ti underlayer is originated from the reinforcement of the grain boundary segregation in CoCrPtTa alloy. Moreover, the transition of the M-H hysteresis pattern with the thickness of Ti underlayer indicates that the major contribution of Ti underlayer is not the magnetocrystalline anisotropy but the shape anisotropy due to the formation of uniform columnar grains by the nonmagnetic alloy segregation.

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The Effects of TMT's Cognitive Traits and CEO Factors on R&D Investment (최고경영진의 인지적 특성과 최고경영자 특성이 R&D투자에 미치는 영향)

  • Hyejin Cho;Gahye Hong
    • Knowledge Management Research
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    • v.24 no.2
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    • pp.65-85
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    • 2023
  • This paper investigates how TMT's cognitive traits affect R&D investment. Drawing on the attention-based view, we propose that TMT's future orientation and risk preference increase the level of R&D investment. As R&D activities have long-term goal of generating proprietary knowledge, it is important to understand how TMT's attention toward future and risk affect R&D investment. Also, we test the moderating effect of CEO duality on R&D investment. As the CEO plays a leadership role in the TMT, if the CEO's decision-making authority is highly concentrated, the impact of TMT on R&D may decrease. We measure CEO duality and CEO ownership stake as CEO characteristics. Based on a sample of 837 U.S. manufacturing firms, the results show that when TMT has a higher tolerance for risk and higher future orientation, R&D intensity increases. However, when CEO also serves as chairman of board and CEO has higher ownership, TMT's influence on R&D investment weakens. This implies that TMT and CEO has power dynamic that can change based on CEO power supporting status. Overall, it suggests that TMT's attention and CEO power are important factors to improve longer-term knowledge accumulation of firm.

Heat Treatment Effects of $Fe_{73.0}Cu{1.0}Nb_{3.5}Si_{14.0}B_{7.6}$Alloy with Imbedded Nanocrystalline Phase under Magnetic Field (초미세결정립과 비정질이 공존하는 $Fe_{73.9}$$Cu_{1.0}$$Nb_{3.5}$$Si_{14.0}$$B_{7.6}$ 합금의 자기장 중 열처리)

  • Yang, J.S.;Son, D.;Cho, Y.
    • Journal of the Korean Magnetics Society
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    • v.8 no.1
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    • pp.13-20
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    • 1998
  • The crystallographic and high frequency characteristics of $Fe_{73.9}Cu_{1.0}Nb_{3.5}Si_{14.0}B_{7.6}$ soft magnetic alloys were investigated under the magnetic field annealing. As-cast ribbon with which already imbedded nanocrystalline Fe-Si phase on the surface have a preferred orientation with (400) plane to surface and also with the [011] direction parallel to the ribbon length. The extra nanocrystalline Fe-Si phase appeared throughout at 45$0^{\circ}C$ in samples with or without the longitudinal magnetic field. However the formation of nanocrystalline phase does not appear on the suface layer until 50$0^{\circ}C$ annealing temperature under the transverse field. The cryststallization fraction of annealed samples with longitudinal magnetic field is higher than that of samples without magnetic field. When the transverse magnetic field is applied, the crystallization fraction does not increases but decreases until 50$0^{\circ}C$. However the crystallization of internal regions can be confirmed by X-ray diffraction measurement via tilting the sample. It was found that for all samples, the saturation induction were all same with 1.3 T. The coercive field of as-cast sample was 1.06 A/cm, but in annealed samples it decrease from 0.56 to 0.1 A/cm with increasing annealing temperature from 400 and 55$0^{\circ}C$, respectively. The squareness of annealed samples under transverse magnetic field has a small value than that of both without field and with longitudinal field annealing.

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MnIr Thickness Dependence of Torque Signals in CoFe/MnIr Thin Films (CoFe/MnIr 박막 재료에서 MnIr의 두께에 따른 토오크 신호 분석)

  • Kim, Dong Young;Yoon, Seok Soo
    • Journal of the Korean Magnetics Society
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    • v.24 no.5
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    • pp.140-145
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    • 2014
  • We analyzed the MnIr thickness dependence of torque signals measured in exchange coupled CoFe/MnIr ($t_{AF}$) bilayers. The measured torque signals were compared with calculated ones by Stoner-Wohlfarth model. The exchange coupling anisotropy $J_c$ was considered for the model calculation between ferromagnetic (F) and antiferromagnetic (AF) layers with uniaxial anisotropy constant of $K_F$ and $K_{AF}$, respectively. The rotational losses were appeared in the range of $0.5t_c$ < $t_{AF}$ < $t_c$ ($=J_c/K_{AF}$) by the unpinned AF layer. While, the unidirectional anisotropy ($J_k$) was caused by the pinned AF layer at $t_{AF}$ > $t_c$. The critical thickness of MnIr layer was $t_c$ = 3.4 nm in CoFe/MnIr bilayers. The rotational losses behavior as shown in $t_{AF}$ = 3 nm sample were explained by the random orientation of the easy axis of AF grains. The unidirectional anisotropy obtained from torque signal of $t_{AF}$ = 10 nm sample was $J_k=0.63J_c$. Thus, the unidirectional anisotropy can be enhanced up to $J_k=J_c$ by aligning the AF easy axis.