• Title/Summary/Keyword: $T_{1/2}$

Search Result 34,718, Processing Time 0.071 seconds

A research study on the relationship of work environments to occupational diseases in dental hygienists (치과위생사의 근무환경과 직업병의 연관성에 대한 조사연구)

  • Nam, Young-Shin;Jang, Jae-Yeon
    • Journal of Korean society of Dental Hygiene
    • /
    • v.11 no.4
    • /
    • pp.581-593
    • /
    • 2011
  • Objectives : The purpose of this study was to examine the relationship of the work environments of dental hygienists to their occupational diseases in a bid to provide some information on their health care, health promotion and the prevention of occupational diseases. Methods : The subjects in this study were 300 dental hygienists who worked in Seoul, urban communities involving large cities and rural areas. One-on-one interviews and a self-administered survey were implemented with their consent. Results : The findings of the study were as follows: 1. 60 percent of the dental hygienists investigated replied that they had occupation-related physical symptoms. By the length of service, the dental hygienists who worked for six to 10 years had the most symptoms. 2. Out of the occupation-related symptoms, the most prevalent symptom was a pain in the shoulders and neck(41%), followed by a pain in the lower back, a pain in the legs, a pain in the wrists and skin diseases. The most painful parts of the body were hands and arms. 3. In regard to the relationship between the general characteristics and the intensity of pain, the highest group of the dental hygienists in Seoul replied that they had a severe pain, and the lowest number of those in the large cities gave the same answer. 4. Concerning the cause of occupational diseases, 65.7 percent cited the wrong posture. 5. As to relationship between the general characteristics and regular hospital-visit experiences for the prevention of pain during work hours, many of the dental hygienists who were in their 40s and 50s visited hospitals from time to time, and many of those in their 20s never did that. 6. In regard to links between the general characteristics and an opinion on the necessity of regular education, many of the respondents from Seoul and urban regions involving large cities considered it necessary to receive education on a regular basis. By daily work hours, the highest number of those who worked for eight hours or less considered that necessary, and lots of those who worked for 11 hours didn't consent to that. The gaps between them were statistically significant(p<0.05). Conclusions : Given the findings of the study, daily work hours and length of service were two integral factors to affect the regular hospital-visit experiences and pain, and the wrong posture was identified as the most common cause of occupational diseases. To ensure the successful prevention of occupational diseases, dental hygiene students should be taught the importance of occupational disease before they start to work, and supplementary education should be provided for dental hygienists to work in the right posture.

Studies on the Glucose Isomerizing Enzyme -Part III The Effects of Metal Ions on the Reaction of K-17 Strain's Glucose Isomerizing Enzyme- (포도당(葡萄糖) 이성화(異性化) 효소(效素)에 관(關)한 연구(硏究) -제3보(第三報) 분리(分離) 선정(選定)된 균주(菌株) 효소(酵素)의 작용(作用)에 미치는 금속염(金屬鹽)의 영향(影響)에 대(對)해서-)

  • Seu, J.H.;Kim, C.K.;Ki, W.K.;Rhee, I.K.;Kwon, T.J.;Woo, D.L.
    • Applied Biological Chemistry
    • /
    • v.11
    • /
    • pp.55-61
    • /
    • 1969
  • This K-17 strain was not absolutely requiring xylose as an inducer for enzyme formations. The most activity of this enzyme was lost when treated at $75^{\circ}C$. for 30 hours but was not influenced at $70^{\circ}C$. for 70 hours of treatment. The activity of this enzyme was increased by the addition of magnesium ions or cobalt ions in the reaction system. In the studies, we found that the magnesium ions simply activate the enzyme reaction and the cobalt ions do not but protect the enzyme from heat inactvation. And it was also found the phosphate buffer solution was very suitable as glucose dissolving solvent on the enzyme reaction. The mixed carbon source medium containing glucose, fructose, sorbitol, xylose and sucrose was more favorable for enzyme production then a sole carbon source containing medium on the shaking culture method.

  • PDF

Comparison Shopping Systems using Image Retrieval based on Semantic Web (시맨틱 웹 기반의 이미지 정색을 이용한 비교 쇼핑 시스템)

  • Lee, Kee-Sung;Yu, Young-Hoon;Jo, Gun-Sik;Kim, Heung-Nam
    • Journal of Intelligence and Information Systems
    • /
    • v.11 no.2
    • /
    • pp.1-15
    • /
    • 2005
  • The explosive growth of the Internet leads to various on-line shopping malls and active E-Commerce. however, as the internet has experienced continuous growth, users have to face a variety and a huge amount of items, and often waste a lot of time on purchasing items that are relevant to their interests. To overcome this problem the comparison shopping systems, which can help to compare items' information with those other shopping malls, have been issued as a solution. However, when users do not have much knowledge what they want to find, a keyword-based searching in the existing comparison shopping systems lead users to waste time for searching information. Thereby, the performance is fell down. To solve this problem in this research, we suggest the Comparison Shopping System using Image Retrieval based on Semantic Web. The proposed system can assist users who don't know items' information that they want to find and serve users for quickly comparing information among the items. In the proposed system we use semantic web technology. We insert the Semantic Annotation based on Ontology into items' image of each shopping mall. Consequently, we employ those images for searching the items instead of using a complex keyword. In order to evaluate performance of the proposed system we compare our experimental results with those of Keyword-based Comparison Shopping System and simple Semantic Web-based Comparison Shopping System. Our result shows that the proposed system has improved performance in comparison with the other systems.

  • PDF

An Analysis of decision Factor on Drive Distance for University Golf Player's Object Execution Using Late Hitting Method (대학 골프선수들의 의도적 지연히팅 시 비거리 결정인자 분석)

  • So, Jea-Moo;Lim, Young-Tae;Kim, Yong-Seok;Cho, Bum-Wook
    • Korean Journal of Applied Biomechanics
    • /
    • v.15 no.3
    • /
    • pp.71-78
    • /
    • 2005
  • The purpose of this research was to conduct an analysis on the factors that determine the distance at the time of target swing based on the use of late hitting of outstanding college golfers to verify the difference between late hitting and the distance that target increases in regular swing and the distance. Then, this research conducts an analysis on the correlation between club head velocity, ball velocity, launch angle, back spin, meet ratio and distance that become kinematics variables at the time of target swing. To attain the above mentioned purpose, 25 outstanding college players with average experience and handicap of 6 years and 5, respectively, were targeted Comparative analysis on two swing that target increase in regular and the distance was conducted by used driver. When it pertained to two types of swing. analysis system comprised of an analytical software called the Science Eye of the Bridgestone and peripheries was used to define the relationship between variables of club head velocity, ball velocity, launch angle, back spin, meet ratio that become kinematics variables. As for the method of processing data pertaining to the factors that determine the distance, differences of distance by the type of swing was verified by using independent T-test that leveraged SPSS 120 statistics program. Moreover, level of correlation between variables that contribute to the increase in distance through relation of correlation, and analysis of tendencies was conducted to analyze tendency of non-distance to increase in accordance to the increase of each variable. Key results produced through this experiment are as follows: 1. Artificial late hitting for increased non-distance that targets skilled players had effect on increased the distance(p<. 05). 2 The drive distance is correlated with each measured variable that is positive correlation to ball velocity, club head velocity, meet ratio and relation of back spin and launch angle are negative correlation. ball velocity and club head velocity are very high correlated with drive distance(p<.01), back spin and distance are negative correlation(p<.01). 3. Among each measured variable increasing the club velocity is the most contribution, and ball velocity and meet ratio and the increasing launch angle and back spin is negative effect for increasing distance.

Evaluation of Insole-equipped Ankle Foot Or thosis for Effect on Gait based on Biomechanical Analysis (인솔 장착형 단하지 보조기의 생체 역학적 분석을 통한 보행 영향성 평가)

  • Jung, Ji-Yong;Kim, Jin-Ho;Kim, Kyung;Trieu, Pham Hai;Won, Yong-Gwan;Kwon, Dae-Kyu;Kim, Jung-Ja
    • Korean Journal of Applied Biomechanics
    • /
    • v.20 no.4
    • /
    • pp.469-477
    • /
    • 2010
  • The purpose of this study was to evaluate the effects of insole-equipped ankle-foot-orthoses (AFO) on gait. 10 healthy males who had no history of injury in the lower extremity participated in this study as the subjects. The foot of each subject was first scanned, and the insole fit to the plantar was made using BDI-PCO(Pedcad Gmbh, Germany). The subject then was made to walk on a treadmill under four experimental conditions: 1) normal walking, 2) walking wearing AFO, 3) walking wearing AFO equipped with the insole, 4) walking wearing pneumatic-ankle-foot-orthosis (pAFO) equipped with the insole. During walking, foot pressure data such as maximum force, contacting area, peak pressure, and mean pressure was collected using Pedar-X system (Novel Gmbh, Germany) and EMG activity of lower limb muscles such as gastrocnemius medial head, gastrocnemius lateral head, and soleus was recorded using MP150 EMG module (BIOPAC System Inc., USA). Collected data was then analyzed using paired t-test in order to investigate the effects of the insole. As a result of the analysis, when insole was equipped, overall contacting area was increased while both the highest peak pressure and the mean pressure were significantly decreased, and EMG activity of the lower limb muscles was decreased. On the contrary, the cases of wearing AFO showed the decreased contacting area and the increased pressures. Therefore, the AFO equipped with a proper insole fit well to the foot can help comfortable walking by spreading the pressure over the entire plantar.

The Characteristics of Spinal Injury in Skiing and Snowboarding Injuries (스키와 스노보드 사고에서 척추손상의 특징)

  • Cha, Yong Sung;Lee, Kang Hyun;Kim, Sun Hyu;Jang, Yong Su;Kim, Hyun;Shin, Tae Yong;Hwang, Sung Oh
    • Journal of Trauma and Injury
    • /
    • v.20 no.1
    • /
    • pp.33-39
    • /
    • 2007
  • Purpose: Few studies have been done for spinal injuries after skiing and snowboarding accidents. Assuming that the riding patterns of skiing and snowboarding were different, we analyzed the differences between the mechanisms, diagnoses and levels of spinal injuries caused by them. The purpose of this study was to gain a better understanding of spinal hazards associated with skiing and snowboarding in order to educate skiers and snowboarders. Methods: We conducted a prospective study of 96 patients who had sustained spinal injuries as a result of skiing and snowboarding accidents from January 2003 to March 2006. We used a questionnaire, radiological studies, history taking, and physical examinations. We analyzed the mechanism of injury, the level of spinal injury, the severity of spinal injury, and the Abbreviated Injury Scale scores (AIS score). We used the t-test and the chi-square test. Results: The skiing and the snowboarding injury group included in 96 patients. The skiing injury group included 30 patients (31.2%), and the snowboarding injury group included the remaining 66 patients (69.8%). The primary mechanism of injury in skiing was collisions and in snowboarding was slip downs (p=0.508). The primary level of spinal injury in skiing and snowboarding was at the L-spine level (p=0.547). The most common athlete ability of the injured person was at the intermediate level (p=0.954). The injured were most commonly at the beginner or the intermediate level (p=0.302). The primary diagnosis of spinal injury in skiing and snowboarding was back spain (p=0.686). The AIS scores did not differed between the two groups (p=0.986). Conclusion: The most common spinal injury after skiing and snowboarding accidents was back sprain. There was no difference in the severity of spinal injury between skiing and snowboarding accidents.

Characteristics of Recycled Wafer for Solar Cell According to DRE Process (DRE 공정이 태양전지용 재생웨이퍼 특성에 미치는 영향)

  • Jung, D.G.;Kong, D.Y.;Yun, S.H.;Seo, C.T.;Lee, Y.H.;Cho, C.S.;Kim, B.H.;Bae, Y.H.;Lee, J.H.
    • Journal of the Korean Vacuum Society
    • /
    • v.20 no.3
    • /
    • pp.217-224
    • /
    • 2011
  • of materials and simplification of process. Micro-blasting is one of the promising method for recycling of waste wafer due to their simple and low cost process. Therefore, in this paper, we make recycling wafer through the micro-blaster. A surface etched by micro-blaster forms particles, cracks and pyramid structure. A pyramid structure formed by micro-blaster has a advantage of reflectivity decrease. However, lifetime of minority carrier is decreased by particles and cracks. In order to solve this problems, we carried out the DRE(Damage Romove Etching). There are two ways to DRE process ; wet etching, dry etching. After the DRE process, we measured reflectivity and lifetime of minority carrier. Through these results, we confirmed that a wafer recycled can be used in solar cell.

Production of Gastrodia elata Tuber using Armillaria spp. (Armillaria 속균을 이용한 천마의 생산)

  • Sung, Jae-Mo;Jung, Bum-Shig;Yang, Keun-Joo;Lee, Hyun-Kyung;Harrington, T.C.
    • The Korean Journal of Mycology
    • /
    • v.23 no.1 s.72
    • /
    • pp.61-70
    • /
    • 1995
  • The genus Armillaria is important because they produce Gastrodia tubers. Seventy two isolates of Armillaria were obtained from fruit bodies grown on decayed wood in Korea. Twenty four isolates from Pinus koraiensis were identified as A. ostoyae. Two isolates from G. elata growing in the field were identified as A. mellea. Seven isolates from Acer ginnala and Quercus spp. were identified as A. tabescens. Thirty nine isolates were identified as A. gallica. Armillaria gallica was isolated from Quercus spp., Ainus japonica, Vitis amurensis and Prunus sargentii. Armillaria spp. isolates were divided into four groups based on the cultural characteristics. Group II (A. gallica KNU-A110) was better than the other groups for mycelial growth and rhizomorph formation. Isolate KNU-A110 proved to be good for production of G. elata tubers. This fungus forms mycelial fan in the plant tissue and rhizomorphs in contact with G. elata tubers. Gastrodia spp. was found in thirteen sites in Kangweon province in Korea. The plants were divided into three different kinds based on stem color. Plants with stems of brownish orange and greyish yellow were identified as G. elata, and those with greyish green colored stems were identified as G. gracilis. Gastrodia was collected mainly from humus soils rich in leaf debris, and slopes facing south from mid-May to mid-July. Once the new tubers are formed from the ancestry tuber, the ancestry tuber begins to decay. The offspring tuber, apparently gaining nutrients through rhizomorphs, begins to grow in length and slowly to enlarge. It takes three years for the offspring tuber to become ancestry tuber.

  • PDF

The Effects of Sustained Natural Apophyseal Glides on Pain and Lumbar Stability in Patient with Chronic Low Back Pain (척추후관절가동술이 만성요통환자의 통증과 요부안정성에 미치는 영향)

  • Lee, Young-Hwa;Kwon, Won-An;Lee, Jea-Hong;Kim, Jun-Hyun;Bae, Sung-Soo
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.3 no.3
    • /
    • pp.203-213
    • /
    • 2008
  • Purpose : The purpose of the study was to investigate the effects of sustained natural appophyseal glides (SNAGS) on pain and lumbar stability in patients with chronic low back pain. Methods : The subjects were assigned randomly devided SNAGS group(n=18) and control group(n=18). The SNAGS group received Infrared(IR) used thermal therapy for 20minutes, Interference current therapy(ICT) used electrical therapy for 10minutes and SNAGS for 10minutes to 15minutes. The control group received IR used thermal therapy for 20minutes, ICT used electrical therapy for 10minutes and active stretching exercise for 10minutes to 15minutes. The visual analogue scale(VAS) and lumbar stability were measured at pre-treatment and post-treatment. Results : The results of this study were summarized as follows : 1. The VAS score of SNAGS group and control group was significantly within-subjects pre-test and post-test (p<.05), there was significantly difference between-subjects on each groups(p<.05). 2. The SNAGS group was significantly increased in variation of lumbar stability on $0^{\circ}$, $180^{\circ}$, $90^{\circ}$, $-90^{\circ}$, $45^{\circ}$, $-45^{\circ}$, $135^{\circ}$ and $-135^{\circ}$ within-subjects pre-test and post-test(p<.05), but The control group wasn't significantly increased in variation of lumbar stability on $0^{\circ}$, $180^{\circ}$, $90^{\circ}$, $-90^{\circ}$, $45^{\circ}$, $-45^{\circ}$, $135^{\circ}$ and $-135^{\circ}$ within-subjects pre-test and post-test(p>.05). There was significantly difference between-subjects on each groups(p<.05). Conclusion : In conclusion, SNAGS found that effective to decrease of pain and increase of lumbar stability. Therefore, the results of this study suggests that SNAGS is beneficial treatment for chronic low back pain.

  • PDF

Study on the Compared between u-Learning and e-Learning based SCORM (SCORM 기반 u-Learning과 e-Learning 비교연구)

  • Choi, Sung;Ryu, Gab-Sang
    • Proceedings of the Korea Society of Information Technology Applications Conference
    • /
    • 2006.06a
    • /
    • pp.495-505
    • /
    • 2006
  • IT기술기반 교육시스템은 인터넷 등장 이전에도 가능성을 인정받아 지속적으로 개발되어 온 분야이며, 교육공학과의 연계로 지식 전날의 이론체계로 각광을 받고 있다. 사이버교유도 인터넷이전부터 다양한 통신방법을 응용하여 개발되었고, 최근 인터넷을 통하여 사이버 교육시스템은 완벽한 기술기반을 갖추게 되였다. 그러나 IT기술의 급격한 변화로 사이버교육시스템은 계속하여 신기술 변화에 적용해야만 한다. 현재 정보통신기술의 변화는 방송 통신망의 융합, 브로드 밴드 네트워킹, 스마트 디바이스의 다양화, 멀티미디어 기술의 고도화로 요약된다. 이 기술의 종합한 작용으로 유비쿼터스 사회의 기반으로 진화되고 있다. 그래서 e-Learning 분야도 기존 인터넷기반 시스템과는 달리 차세대 온라인교육시스템으로 친화되고 있다. IT융합가술 기반의 온라인 교육시스템은 각종 국제표준단체에서 표준안이 제시되고 있다. e-Learning 시스템이란 선기술 기반을 반영한 표준기술을 사용하는 온라인교육시스템을 포괄하는 개념이다. 본 연구에서는 e-Learning 시스템과 유비쿼터스 기술을 반영한 e-Learning을 비교하였다. 그리고 u-Learning 시스템의 기술정립과 EOD(Education On Demand) 시스템에 대하여 연구하였다. 1. u-Learning 정의 정보산업분야를 비롯한 문화, 교육 등 모든 분야에서 유비퀴터스라는 수식어가 붙어 다니고 있다. e- Learning 교육 업계에 따르면 10년 후에는 유비쿼터스는 대중화가 될 것이며, 부가가치 규모는 100조 원에 이를 것으로 추정된다. 그래서 교육산업도 주변 환경이 아날로그 방식에서 IT 기반에 의한 디지털 환경으로 변화되고 있다. 또한 e러닝, T러닝, m러닝, u러닝 등의 용어가 생성되고 있다.키지에어컨에서 사용되고 있는 밀폐형 압축기에 대해서 그림 2에서 나타내고 있는 냉방능력 10tons(120,000Btu/h) 이하를 중심으로 상기의 최근 기술 동향을 간략하게 소개하고자 한다.질표준의 지표성분으로 간주되는 진세노사이드의 절대함량과 그 성분조성 차이에 따른 임상효과의 차별성이 있는지에 대한 검토와, 특히 최근 실험적으로 밝혀지고 있는 사포닌 성분의 장내 세균에 의한 생물전환체의 인체 실험을 통한 효과 검정이 필요하다. 나아가서는 적정 복용량의 설정과 이와 관련되는 생체내 동태 및 생체이용율(bioavilability)에 관한 정보가 거의 없으므로 이것도 금후 검토해야 할 과제로 사료된다. 인삼은 전통약물로서 오랜 역사성과 그동안의 연구결과에 의한 과학성을 가지고 있으므로 건강유지와 병의 예방 및 회복촉진을 위한 보조요법제 또는 기능성 식품으로써의 유용성이 있는 것으로 판단된다. 앞으로 인삼의 활용성 증대를 위해서는 보다 과학적인 임상평가에 의한 안전성 및 유효성 입증과 제품의 엄격한 품질관리의 필요성이 더욱 강조되어야 할 것이다.xyl radical 생성 억제 효과를 보여 주었다. 본 실험을 통하여 BHT 를 제외하고 전반적으로 세포 수준에서의 oxidative stress 에 대한 억제 효과를 확인해 볼 수 있었으며 특히 수용성 항산화제들에서 두드러진 효과를 보여 주었다. 제공하여 내수기반 확충에도 노력해야 할 것 이다.있었다., 인삼이 성장될 때 부분적인 영양상태의 불충분이나 기후 등에 따른 영향을 받을 수 있기 때문에 앞으로 이에 대한 많은 연구가 이루어져야할 것으로 판단된다.태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$<

  • PDF