• Title/Summary/Keyword: non-existence

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Properties and defects of Mn-Zn Ferrite single crystals grown by the modified process (연속 성장법으로 성장된 Mn-Zn Ferrite 단결정 특성 및 결함)

  • 정재우;오근호
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.1 no.2
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    • pp.23-33
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    • 1991
  • Mn - Zn Ferrite has the natural characteristics of incongruent melting and the zinc oxide evaporation while the crystal is being grown. As a result of these, it comes into existence to be a non-uniform distribution of cations along the crystal growth axis and also Pt particles are usually precipitated into the crystals in Bridgman method since the melt zone is maintained for a long time in the crucible. These have bad effects on the magnetic properties of ferrites. But, to overcome these faults and then acquire the better single crystals. new modified growth method was developed and the growth factors were investigated as following: melt height in the crucible, surface tension and density of melt, the behavior of melt at interface, the shapes of crucible and solid -liquid interface, powder feeding rate, and the crystal growing speed. In additon, when we analyzed the compositional fluctuations of grown crystals, they were supressed within 1.5 mol% $Fe_20_3$, 2 mol% MnO, ZnO respectively with comparing to initial composition of crystal and the microstructures of crystals on the(110) plane were observed by optical microscope through the chemical etching technique and the magnetic properties were determined.

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A Comparative Study of University Student's Self-Esteem According to General Characteristics and Orthodontic Treatment (대학생의 일반적 특성 및 교정치료에 따른 자존감 비교연구 - 대구, 경북지역 대학생을 중심으로 -)

  • Kim, Hong-Sik;Song, Jae-Sang;Lim, Byung-Chul
    • Journal of Technologic Dentistry
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    • v.34 no.4
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    • pp.381-390
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    • 2012
  • Purpose: The goal of this study is to investigate the correlation of orthodontic treatment with self-esteem and how orthodontic treatment has an effect on university student's self-esteems by investigating and analyzing the difference in self-esteem of each general characteristic and the difference in self-esteem according to the existence or nonexistence of malocclusion and orthodontic treatment for adult university students. Methods: This study conduced a survey for 420 university students including dental related department, department of health and department of non-dental health in two universities located in Taegu, Gyeongbuk-do province from May 15, 2012 to May 30, 2012, and in 420 questionnaires of the investigated 420 target students, total 400(95.2%) questionnaires except for the questionnaires with falsely or erroneous responses were used for study analysis. Results: In the relations of general characteristic with self-esteem, for self-esteem by each gender, male student showed higher, for self-esteem by residential area, the university student residing at metropolitan area showed higher, for self-esteem by financial status, high class and middle class students in home financial status showed higher, for self-esteem by face shape, the student with triangular face shape showed higher, and in the relation of self-esteem with orthodontic treatment, the university student who is getting orthodontic treatment showed higher self-esteem statistically significantly. Conclusion: For gender, male university student, for residential area, the university student residing at metropolitan area, the high class university student in financial status, the university student with triangular face shape, and the university student who is getting orthodontic treatment showed statistically significantly higher self-esteem.

Measurement of the occipital alpha rhythm and temporal tau rhythm by using magnetoencephalography

  • Kim, J.E.;Gohel, Bakul;Kim, K.;Kwon, H.;An, Kyung-min
    • Progress in Superconductivity and Cryogenics
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    • v.17 no.4
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    • pp.34-37
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    • 2015
  • Developing Magnetoencephalography (MEG) based on Superconducting Quantum Interference Device (SQUID) facilitates to observe the human brain functions in non-invasively and high temporal and high spatial resolution. By using this MEG, we studied alpha rhythm (8-13 Hz) that is one of the most predominant spontaneous rhythm in human brain. The 8-13 Hz rhythm is observed in several sensory region in the brain. In visual related region of occipital, we call to alpha rhythm, and auditory related region of temporal call to tau rhythm, sensorimotor related region of parietal call to mu rhythm. These rhythms are decreased in task related region and increased in task irrelevant regions. This means that these rhythms play a pivotal role of inhibition in task irrelevant region. It may be helpful to attention to the task. In several literature about the alpha-band inhibition in multi-sensory modality experiment, they observed this effect in the occipital and somatosensory region. In this study, we hypothesized that we can also observe the alpha-band inhibition in the auditory cortex, mediated by the tau rhythm. Before that, we first investigated the existence of the alpha and tau rhythm in occipital and temporal region, respectively. To see these rhythms, we applied the visual and auditory stimulation, in turns, suppressed in task relevant regions, respectively.

A Study on the Dematerializing Tendency in Contemporary Space Design (공간디자인의 비(非)물질화 경향에 관한 연구)

  • 권영걸
    • Korean Institute of Interior Design Journal
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    • no.22
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    • pp.61-68
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    • 2000
  • This paper illustrates what the reality of architectural concepts, materials, notions and phenomena are as central questions of contemporay space design. These issues form the goal of modern space design which should attain to the reality of an era when non-real values prevail. Despite the trends of an everchanging and ephemeral dominating quality in architecture for the last ten years, architects still aim to contruct everlasting space on earth. The trends of dematerialization in today's space design can be substantiated in spatial-temporal dimensions as follows. First of all, ephemeral architecture with concepts of hypothetical temporality, everchanging architecture in fluidity, and the transparent architecture with the floating and overlapping image can be analyzed in the dimension of 'time'. In terms of 'space', void quality for the expression of emptiness, neutral space by the simplified and summarized forms, expanded space through ambiguous boundaries and spatial repetition can becharacterized and also be intended strategies for lightness, state of flux, ambiguity, paradox etc., lead modern space design along that path. As this point, we need to pay attention to the so-called 'hypersurface' concept proposed by Stephen Perella. Hypersurface is a sort of cladding sheathing existence independent from the primary structure. With it, the integration between form and image can be achieved. Sometimes hypersurface can be a strategical screen for image projection, a cognitive receptor for surroundings as well as a catalyst for information and communication systems. When the situation dematerializes more and more as the years go on, the concept of hypersurface can be an inclusive method between the phenomenological form in architecture and its self recipient image. Permissive atmospheres created between them in contemporary space design and new paradigms emerged with digital technology will further reinforce the human space's dynamism.

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The Burden in Women with Hysterectomy (자궁절제 여성의 부담감에 관한 연구)

  • Seong, Mi-Hye
    • Women's Health Nursing
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    • v.3 no.2
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    • pp.180-191
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    • 1997
  • When women are removed with their matrix which is a emotionally significant organ of symbol in psychologically adapting themselves to mother and woman, that is threatened and injured with woman role decisively. The nursing for women with hysterectomy is limited to medical treatment and the nursing related to troubles in psychology, emotion they experience in general situation due to operations is hardly realized. New basis for nursing can be realized when we both have relation with lived human experience related th health and become to be a part of it. We need to catch their experience due to the loss of matrix to understand women with hysterectomy. The subjects of the study were nine patients who were admitted to a gynecological ward of a hospital in Seoul, suffering from vaginal bleeding, back pain, abdominal pain and so on and diagnosing as non-cancer. The data were collected from April to May 1997 by listening to the subjects' expression of their experience and by participant observation of the subjects' reactions. A tape-recorder was used under the permission of the subjects, to prevent the loss of spoken information. The result of the study was as follows : The data on burden content from the interview were categorized as psych-emotional, physical, personal interaction, financial burden and maternal role burden. The factors which have influence on the burden of the subjects are an offer of information, support system, age, occupation, economic situation, family history, character, season, the existence of ovary and religion. In conclusion, since we ascertained that the nursing in the process of recovery decide the quality of life, though women with hysterectomy undergo various burden experience and adapt to it in the end, it is necessary to give them enough information and educate husband, having on important effect on the burden experience, to be a good supporter. And technically skilled nurses of consultant are thought to be able to contrive better qualitative life of women with hysterectomy as an important bridge between the subjects and their required information, since the nurses have their well-formed position of relationship of confidence through continuous contact with patients and their family.

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Factors Delaying Presentation of Sudanese Breast Cancer Patients: an Analysis Using Andersen's Model

  • Salih, Alaaddin M;Alfaki, Musab M;Alam-Elhuda, Dafallah M;Nouradyem, Momin M
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.2105-2110
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    • 2016
  • Purpose: A multicenter, observational, cross-sectional study was conducted to assess factors delaying presentation of breast cancer cases. Materials and Methods: Data were collected from a pair of highly specialized referral centers, both located in the center of the Sudanese capital, Khartoum. For a total of 153 eligible respondents, durations of delay, clinicodemographic factors and reasons of referral were collected from our respondents through self-administered questionnaires. Logistic regression analysis and ANOVA were used to test the relation between periods of delay and different factors. Odd ratios (OR's) and their correspondent Confidence intervals (95% CI's). Delay periods were studied with Andersen's model. Results: The average duration of delay in our study was 11.9 (${\pm}11.2$) months. Only a quarter of our patients presented early within the first 3 months after onset of their symptoms. About 47.7% arrived later during the course of the first year, while it took beyond that for the last 27% to come. A prior diagnosis of BC was the only predictor of early presentation (for 3-12 months OR=9.6 (p<0.00), 95% CI 9.55-9.75; for >12 months OR=9.3 (p<0.00), 95% CI 9.33-9.33). Out of the 12 different reasons for delay given by our respondents, none showed a significant difference between patients presenting early or late. Financial incapacity (17.5%), ignorance about BC (14.3), and misinterpreting symptoms (12.7%) were the top three whys of delay. Conclusions: Our findings support existence of a non-uniform pattern of delay among Sudanese BC patients. Changing currently adopted awareness elevating strategies into much more inclusive approaches is strongly recommended.

The Study on Cu2ZnSnSe4 Thin Films without Annealed Grown by Pulsed Laser Deposition for Solar Cells

  • Bae, Jong-Seong;Byeon, Mi-Rang;Hong, Tae-Eun;Kim, Jong-Pil;Jeong, Ui-Deok;Kim, Yang-Do;O, Won-Tae
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.398.1-398.1
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    • 2014
  • The $Cu_2ZnSnSe_4$ (CZTSe) thin films solar cell is one of the next generation candidates for photovoltaic materials as the absorber of thin film solar cells because it has optimal bandgap (Eg=1.0eV) and high absorption coefficient of $10^4cm^{-1}$ in the visible length region. More importantly, CZTSe consists of abundant and non-toxic elements, so researches on CZTSe thin film solar cells have been increasing significantly in recent years. CZTSe thin film has very similar structure and properties with the CIGS thin film by substituting In with Zn and Ga with Sn. In this study, As-deposited CZTSe thin films have been deposited onto soda lime glass (SLG) substrates at different deposition condition using Pulsed Laser Deposition (PLD) technique without post-annealing process. The effects of deposition conditions (deposition time, deposition temperature) onto the structural, compositional and optical properties of CZTSe thin films have been investigated, without experiencing selenization process. The XRD pattern shows that quaternary CZTSe films with a stannite single phase. The existence of (112), (204), (312), (008), (316) peaks indicates all films grew and crystallized as a stannite-type structure, which is in a good agreement with the diffraction pattern of CZTSe single crystal. All the films were observed to be polycrystalline in nature with a high (112) predominant orientation at $2{\theta}{\sim}26.8^{\circ}$. The carrier concentration, mobility, resistivity and optical band gap of CZTSe thin films depending on the deposition conditions. Average energy band gap of the CZTSe thin films is about 1.3 eV.

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A Study on Basin Characteristics of Small Stream System (소하천 수계의 유역특성에 관한 연구)

  • An, Sang-Jin;Yun, Yeong-Nam;Gang, Gwan-Won
    • Water for future
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    • v.10 no.1
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    • pp.71-77
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    • 1977
  • The stream morphological characteristics of a watershed play a significant role in the analysis of rainfall-runoff relations in a river basin and a quantitative description of these characteristics is essential for determining the appropriate values of physical parameters of a watershed which usually are input data for rainfall-runoff simulation models. In this study the stream morphological characteristics of the Gab River basin, which is one of the three major tributaries of Geum River, was determined quantitatively by the Horton-Strahler's method. The result showed that the Gab River System was developed very closely to the patterns generally described by the laws of Horton. The basic relations concerning the morphological characteristics deriveed in this study are the relations of stream length, and average stream slope, the stream length-drainage area relation, relative height-relative drainage area relation, and the relation between the proportional stream order and drainage area. No correlation analysis was possible between the morphological parameters and the streamflow due to non-existence of the stage gauging stations on the Gab River System.

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Inter-comparison of Prediction Skills of Multiple Linear Regression Methods Using Monthly Temperature Simulated by Multi-Regional Climate Models (다중 지역기후모델로부터 모의된 월 기온자료를 이용한 다중선형회귀모형들의 예측성능 비교)

  • Seong, Min-Gyu;Kim, Chansoo;Suh, Myoung-Seok
    • Atmosphere
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    • v.25 no.4
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    • pp.669-683
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    • 2015
  • In this study, we investigated the prediction skills of four multiple linear regression methods for monthly air temperature over South Korea. We used simulation results from four regional climate models (RegCM4, SNURCM, WRF, and YSURSM) driven by two boundary conditions (NCEP/DOE Reanalysis 2 and ERA-Interim). We selected 15 years (1989~2003) as the training period and the last 5 years (2004~2008) as validation period. The four regression methods used in this study are as follows: 1) Homogeneous Multiple linear Regression (HMR), 2) Homogeneous Multiple linear Regression constraining the regression coefficients to be nonnegative (HMR+), 3) non-homogeneous multiple linear regression (EMOS; Ensemble Model Output Statistics), 4) EMOS with positive coefficients (EMOS+). It is same method as the third method except for constraining the coefficients to be nonnegative. The four regression methods showed similar prediction skills for the monthly air temperature over South Korea. However, the prediction skills of regression methods which don't constrain regression coefficients to be nonnegative are clearly impacted by the existence of outliers. Among the four multiple linear regression methods, HMR+ and EMOS+ methods showed the best skill during the validation period. HMR+ and EMOS+ methods showed a very similar performance in terms of the MAE and RMSE. Therefore, we recommend the HMR+ as the best method because of ease of development and applications.

Postnatal Expressional Patterns of Adipose-Associated Molecules in the Mouse Proximal Epididymal Fat

  • Lee, Ki-Ho
    • Development and Reproduction
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    • v.23 no.4
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    • pp.313-322
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    • 2019
  • The epididymal fat pad is a male gonadal adipocyte tissue and is histochemically separated into distal and proximal parts. The development of epididymal fat during postnatal period has not been examined in detail. A previous research showed that expression of adipocyte-associated molecules in the distal epididymal fat of mouse is generally increased as postnatally aged. In the present study, expressional patterns of same adipocyte-associated molecules in the mouse proximal epididymal fat at 2, 5, 8, and 12 months of age were studied by quantitative real-time PCR analysis and were compared with those in the distal epididymal fat. The expressional levels of peroxisome proliferator-activated receptor gamma (Pparg), lipoprotein lipase (Lpl), and fatty acid synthase (Fasn) at 5 months of age were significantly lower than those at 2 months of age, while transcript level of leptin (Lep) at 5 months was higher than that at 2 months of age. The transcript levels of all molecules at 8 months of age were significantly increased, compared with those at 2 and 5 months of age. At 12 months of age, expression of delta like non-canonical Notch ligand 1 (Dlk1) was further significantly increased, while there was no change on the transcript level of Pparg and significant decreases of Fabp4, Retn, Lpl, Lep, Fasn, and adiponectin (Adipoq) transcript levels. The current findings show that expressional patterns of molecules associated with adipocyte in the proximal epididymal fat is somewhat different with those of the distal epididymal fat, suggesting the existence of regional variance in the epididymal fat.