• Title/Summary/Keyword: relaxation times

Search Result 389, Processing Time 0.027 seconds

Magnetic Properties of Superparamagnetic Ni-Zn Ferrite for Nano·Bio Fusion Applications (나노·바이오 융합응용을 위한 초상자성 Ni-Zn Ferrite의 자기적 특성연구)

  • Lee, Seung-Wha;Ryu, Yeon-Guk;Yang, Kea-Joon;An, Jung-Su;Kim, Chul-Sung
    • Journal of the Korean Magnetics Society
    • /
    • v.15 no.2
    • /
    • pp.100-105
    • /
    • 2005
  • $Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticles have been prepared by a sol-gel method. The structural and magnetic properties have been investigated by DTA/TGA, XRD, SEM, and $M\ddot{o}ssbauer$ spectroscopy, VSM. $Ni_{0.9}Zn_{0.1}Fe_2O_4$ powder that was annealed at $300^{\circ}C$ has spinel structure and behaved superparamagnetically. The estimated size of superparammagnetic Ni-Zn ferrite nanoparticle is around 10 nm. The hyperfine fields at 13 K for the A and B patterns were found to be 533 and 507 kOe, respectively. The blocking temperature ($T_B$) of superparammagnetic $Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticle is about 250 K. The magnetic anisotropy constant and relaxation time constant of $Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticle were calculated to be $1.6\times10^6\;ergs/cm^3$ and ${\tau}_0=5.0{\times}10^{-13}$ s, respectively. Also, Temperature increased up to $43^{\circ}C$ within 10 minutes under AC magnetic field of 7 MHz. It is considered that $Ni_{0.9}Zn_{0.1}Fe_2O_4$ powder that was annealed at $300^{\circ}C$ is available for biomedicine application such as hyperthermia, drug delivery system and contrast agents in MRI.

Establishment of a Buddhist Arboretum through a Survey of Temple Managers and Laypersons (사찰림 관리자와 일반인의 인식조사를 통한 불교수목원 조성방안)

  • Yi, Young-Kyoung;Yi, Pyong-In
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.42 no.1
    • /
    • pp.104-114
    • /
    • 2014
  • Nowadays, forests have been recognized as valuable resources for biological diversity and tourism/recreation. Temple forests occupy 1.3% of all the Korean forest and are under weak management although their ecological states are very good. Currently in the Buddhist society, the concern for the Buddhist arboretum has been raised as a good alternative for the practical use of temple forests to secure the sustainability of the temple forests as well as to actively meet the demand of the times for forests. This study aims to suggest establishment measures of Buddhist arboretum. This survey was performed on 105 temple forest managers and 130 laypersons. To summarize the results, the two groups differ in opinion. The temple forest managers more concerned for advertizing Buddhist culture and enhancing the image of the temple, while the laypersons had higher expectations for relaxation and education. However, they are similar in putting more emphasis on the conserving the heritage value of the temple and managing the temple forest. Above all, both groups evaluated the needs higher than the urgency and perceived managing temple forest as the most crucial function of a Buddhist arboretum. They also thought that a Buddhist arboretum should be planned to respond to the ecological characteristics of the temple area as well as to be non-exclusive to its users. Based on the important findings, five suggestions for a Buddhist arboretum were proposed. First, a Buddhist arboretum should be carried forward from a long-term point of view, developing a bond of sympathy between members of Buddhist society as well as conducting promotion and education to the general public. Second, the most significant function of a Buddhist arboretum should be preserving the temple forest, with the emphasis on relaxation and education. Third, in order to provide nonexclusive use, a Buddhist arboretum should provide mixed programs applicable to diverse user groups for high user satisfaction and educational effects. Fourth, the Buddhistic identification could be obtained through variety of plants closely associated with Buddhist culture. Lastly, in the process of collecting plants, it is also crucial to reflect the image of the temple and resource property so as to contribute itself in conservation and management of original temple forests. Thereby all Buddhist Arboretum can be classified into two types; preservation/collection and display/education/rest.

Interface study of ion irradiated Cu/Ni/Cu(001)/Si thin film by X-ray reflectivity (이온 조사된 Cu/Ni/Cu(001)/Si 자성박막에 있어서 X-ray reflectivity를 이용한 계면 연구)

  • Kim, T.G.;Song, J.H.;Lee, T.H.;Chae, K.H.;Hwang, H.M.;Jeon, G.Y.;Lee, J;Jeong, K.;Whang, C.N.;Lee, J.S.;Lee, K.B.
    • Journal of the Korean Magnetics Society
    • /
    • v.12 no.5
    • /
    • pp.184-188
    • /
    • 2002
  • The Cu/Ni/Cu(002)/Si(100) films which have perpendicular magnetic anisotropy were deposited by e-beam evaporation methods. From the reflection high energy electron diffraction pattern, the films were confirmed to be grown epitaxially on silicon. After 2X lots ions/$\textrm{cm}^2$ C+ irradiation, magnetic easy-axis was changed from surface normal to in-plane as shown in the hysteresis loop of magneto-optical Kerr effects. It became manifest from analysis of X-ray reflectivity and grazing incident X-ray diffraction that even though interface between top Cu layer and Ni layer became rougher, the contrast of Cu and Ni's electron density became manifest after ion irradiation. In addition, the strain after deposition of the films was relaxed after ion irradiation. Strain relaxation related with change of magnetic properties and mechanism of intermixed layer's formation was explained by thermo-chemical driving force due to elastic and inelastic collision of ions.

Structural Model Analysis of Changes in Women's Quality of Life and Life Satisfaction by Body Shape Management

  • Kim, Jae-Nam
    • Journal of the Korea Society of Computer and Information
    • /
    • v.25 no.10
    • /
    • pp.211-219
    • /
    • 2020
  • The purpose of this study is to conduct body shape management on women for a certain period of time to determine the structural relationship between the latent variables of life habits, social support, and life satisfaction and the impact on the quality of life. Body shape management was performed with chiropractic adjustments and myofascial relaxation therapy, and a physical therapist with 25 years of experience was used as an expert. The subject of the study was a sample of women in their 20s to 60s residing in Gwangju Metropolitan City, and women who participated in body shape management procedures more than 20 times for the study were asked to fill out a questionnaire using a self-evaluation writing method. The final analysis target was 100 people who made it reasonable to analyze the data. As a result of the study, it was found that the quality of life of women related to health can vary depending on the presence and degree of body shape management. In addition, the degree of life satisfaction varies according to the level of lifestyle and social support, and the direct, indirect, and total effects of the latent variables related to the quality of life were all significant. In this study, the usual body shape management that can improve the quality of life of women gives meaning to the opportunity for women to have desirable lifestyle and to give them a recognition that values quality of life.

The Flora in Chungnyeongsan and Seorisan (경기도 축령산과 서리산 일대의 식물상)

  • 이유미;김성식;조동광;정승선
    • Korean Journal of Environment and Ecology
    • /
    • v.16 no.1
    • /
    • pp.104-123
    • /
    • 2002
  • The flora survey on Chungnyeongsan and Seorisan was conducted 6 times from 1998 to 2000.817 taxa such as 112 families 415 genera 688 species 1 subspecies 116 varieties 12 forma were recorded. Dominant species in investigated areas was Quercus mongozica and some deciduous broad-leaved species, such as Quercus sp., Acer sp., Fraxinus sp., Carpinus sp., etc. were codominant species in these areas. Pinus koraiensis and Larix teptozepis plantations were also found in these areas. The 16 taxa of rare plants protected by Forestry Service were found in these areas and among them 10 taxa were new populations which had not been recorded in these areas. Discovery of Erunthis stellata, Aconitum koreanum, Paeonia japonica, Scopotia japonica and Acunthopanax senticosus populations indicate that these areas could be regarded as very important one in a biogeographical aspect. Endemic plants were listed 35 taxa and among them 22 taxa including Corydalis maculata, Ulmus macrocarpa, Scrophutaria horuiensis, Cirsium setidens, etc. were new one. Naturalized plants were listed 39 taxa and among them 30 taxa were new one. Lower naturalized index(NI) and higher urbanized index(UI) were recorded compared to those of neighbored areas. There were many kinds of threatening factors fur the plant resources in survey areas, so it is necessary to limit the number of visitors and to introduce the natural relaxation system.

Effect of Therapeutic Gymnastic Ball Exercise in Patients With Chronic Low Back Pain (만성 요통환자의 치료를 위한 치료용 볼 운동의 효과)

  • Lee, Eun-Young;Bang, Yoo-Soon;Ko, Ja-Kyung
    • Physical Therapy Korea
    • /
    • v.10 no.3
    • /
    • pp.109-126
    • /
    • 2003
  • This study was designed 10 investigate the effects of therapeutic gymnastic ball exercise on pain, flexibility, lumbar disability level and daily activity levels in male patients of the armed forces medical hospital who complain of chronic low back pain. Twenty-three males were placed in the experimental group and twenty-nine males were placed in the control group. All of the subjects were chosen on the basis of availability among in-patients who were diagnosed with low back pain. The control patients were matched to the experimental group and they were selected considering gender, pain duration and age. Gymnastic ball exercise therapy was developed by the author with the assistance of a rehabilitation specialist. Gymnastic ball exercise therapy includes muscle relaxation, flexibility, muscle strength and posture development exercises. The gymnastic ball exercise therapy was carried out by the experimental group three times a week for eight weeks. Before and after the experiments, the intensity of pain, the lumbar joint mobility (flexibility), the lumbar disability levels, and the daily activity levels of the subjects were measured, respectively. The intensity of pain and the lumbar disability levels were measured by the Visual Analogue Scale, the level of flexibility by a measurement ruler, and the level of disability by the Oswestry Low Back Pain Disability Scale. Data were analysed using a t-test, a paired t-test and an unpaired t-test. The results were as follows: 1. The intensity of pain in the lumbar spine in the experimental group was significantly decreased compared with that of the control group during the 4th week and 8th week. 2. The flexibility of the lumbar spine in the experimental group was significantly increased compared with that of the control group during the 4th week and 8 week. 3. The level of pain caused by anterior, posterior, left lateral and right lateral bending and by rotation in experimental group was significantly decreased compared with that of the control group. 4. The Oswestry Disability score of the experimental group was significantly increased compared with that of control group. These findings indicate that gymnastic ball exercise therapy could be effective in decreasing pain and lumbar disability, and increasing the daily activity levels and lumbar flexibility in patients with chronic low back pain. The study also suggests that gymnastic ball exercise therapy could be an essential factor for effective nursing intervention for patients suffering from chronic low back pain.

  • PDF

Scoping Review of Occupational Therapy in Hospice and Palliative Care (호스피스 작업치료에 관한 범위 고찰)

  • Kim, Ji-yoon;Kim, Hwan
    • The Journal of Korean society of community based occupational therapy
    • /
    • v.7 no.2
    • /
    • pp.33-45
    • /
    • 2017
  • Objective : This study is to provide basic data for hospice occupational therapy and to develop hospice occupational therapy curriculum in Korea. Methods : 45 articles were selected from CINAHL, MEDLINE, and Scopus, which were published from 1980 to 2013. The selected articles were analyzed in term of study year, study source, author's characteristics, study subjects, and study designs. Results : The number of studies have increased steadily since the 1980's. A total of 21 research journals was published, and the most highest published journals were American Journal of Occupational Therapy. Qualitative research methodology was employed four times more than quantitative research methodology. Interventions included various formats such as crafts, ADLs trainings, relaxation techniques, care giver educations and applications of spirituality. The doing-being-becoming theoretical framework and the model of human occupation applied to hospice or palliative patients as a theoretical foundation. Conclusion : Hospice occupational therapy has been developed along with hospice and palliative medicine. There also appeared to be a balance on both clinical trials and researches The hospce occupational therapy care has being studied deeply with various topic. More efforts on curriculum developments as well as clinical advances pertinent to the palliative care should be proceed to warrant making the start of the hospice and palliative occupational therapy in Korea.

Construction of T$_1$ Map Image (T1 이완시간의 영상화)

  • 정은기;서진석;이종태;추성실;이삼현;권영길
    • Progress in Medical Physics
    • /
    • v.6 no.2
    • /
    • pp.83-92
    • /
    • 1995
  • The T1 mapping of an human anatomy may give a characteristic contrast among the various tissues and the normal/abnormal tissues. Here, the methodology of constructing T1 map out of several images with different TRs, will be described using non-linear curve fitting. The general curve fitting algorithm requires the initial trial values T1t and Mot for the variables to be fitted. Three different methods of suppling the trial T1t and Mot are suggested and compared for the efficiency and the accuracy. The curve-fitting routine was written in ANSI C and excuted on a SUN workstation. Several distilled-water phantoms with various concentrations of Gd-DTPA were prepared to examine the accuracy of the curve-fitting program. An MR image was used as the true proton density image without any random noise, and several images with different TRs were generated with the theoretical T1 relaxation times 250, 500, and 1000msec. The random noise of 1, 5, and 10% were embedded into the simulated images. These images were used to generate the T1 map, and the resultant T1 maps for each T1 were analyzed to study the effect of the random noise on the T1 map.

  • PDF

Characteristics of Potassium Channel in the Isolated Rat Detrusor Muscle (흰쥐 배뇨근에 존재하는 potassium 통로의 특성)

  • Jang, Myeong-Soo;Choi, Eun-Me;Ha, Jeoung-Hee;Lee, Kwang-Youn;Kim, Won-Joon
    • Journal of Yeungnam Medical Science
    • /
    • v.11 no.2
    • /
    • pp.363-374
    • /
    • 1994
  • The purpose of this study was to investigate the characteristics or the potassium channels existing in the rat urinary bladders. Smooth muscle strips of rat detrusor urinae were examined by isometric myography. Relaxation responses of detrusor muscle strips to the three potassium channel openers pinacidil, a cyanoguanidine derivative, BRL 38227, a benzopyran derivative and RP 52891, a tertrahydrothiopyran derivative were examined. The potassium channel openers reduced the basal tone, and the rank order of potency was RP 52891>pincidil>BRL 38227. Procaine, an inhibitor of the voltage-sensitive potassium channel tended to increase the basal tone, but it did not affect the relaxant effects of the calcium-activated potassium channel opener did not antagonize the relaxant effects, but it reduced the Emax of RP 52891 and BRL 38227. Glibenclamide, an inhibitor of the ATP-sensitive potassium channel, antagonized the relaxant effects of pinacidil, RP 52891 and BRL 38227 reducing the Emax of RP 52891 and BRl 38227. Galanin which inhibits secretion of insulin through opening the ATP-sensitive potassium channels in pancreatic ${\beta}$-cells rather increased the basal tone of the isolated detrusor strips. These results suggest that the urinary bladder of the rat has mainly the ATP-sensitive, glibenclamide sensitive potassium channel, which is a different type from that in the pancreatic ${\beta}$-islet cells..

  • PDF

Magnetization Reversal Behavior of Submicron-sized Magnetic Films in Response to Sub-ns Longitudinal Field Pulses Along the Easy Axis (1 ns 이하의 자화 용이축 펄스 자기장에 의한 자성박막의 자화 반전 거동)

  • Lee, Jin-Won;Han, Yoon-Sung;Lee, Sang-Ho;Hong, Jong-Ill
    • Journal of the Korean Magnetics Society
    • /
    • v.17 no.5
    • /
    • pp.188-193
    • /
    • 2007
  • We simulated the magnetization reversal behavior of submicron-thickness magnetic films by applying pulses of sub-ns-long durations and amplitudes along the easy axis. The films were rectangular and elliptical $Ni_{80}Fe_{20}$, and their thickness was 2 nm and 4 nm. We observed different behaviors depending upon the shape and thickness of the films and found a normal non-switching in regions in which we expected complete switching after relaxation. In the elliptical film, the non-switching regions were found to be random and to be widely distributed throughout the switching map. The strong demagnetization field along the z-axis, the film thickness direction, is likely responsible for this abnormal behavior. In the rectangular film, the abnormal non-switching regions were less distributed than they were in the elliptical film due to edge domains resulting from the small $M_z$ or demagnetization field during the switching. Our simulation confirms that large demagnetization is detrimental to the ultra-fast magnetization reversal of magnetic ultra-thin films.