• 제목/요약/키워드: 154

검색결과 7,010건 처리시간 0.044초

Highly Doped Nano-crystal Embedded Polymorphous Silicon Thin Film Deposited by Using Neutral Beam Assisted CVD at Room Temperature

  • 장진녕;이동혁;소현욱;홍문표
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.154-155
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    • 2012
  • The promise of nano-crystalites (nc) as a technological material, for applications including display backplane, and solar cells, may ultimately depend on tailoring their behavior through doping and crystallinity. Impurities can strongly modify electronic and optical properties of bulk and nc semiconductors. Highly doped dopant also effect structural properties (both grain size, crystal fraction) of nc-Si thin film. As discussed in several literatures, P atoms or radicals have the tendency to reside on the surface of nc. The P-radical segregation on the nano-grain surfaces that called self-purification may reduce the possibility of new nucleation because of the five-coordination of P. In addition, the P doping levels of ${\sim}2{\times}10^{21}\;at/cm^3$ is the solubility limitation of P in Si; the solubility of nc thin film should be smaller. Therefore, the non-activated P tends to segregate on the grain boundaries and the surface of nc. These mechanisms could prevent new nucleation on the existing grain surface. Therefore, most researches shown that highly doped nc-thin film by using conventional PECVD deposition system tended to have low crystallinity, where the formation energy of nucleation should be higher than the nc surface in the intrinsic materials. If the deposition technology that can make highly doped and simultaneously highly crystallized nc at low temperature, it can lead processes of next generation flexible devices. Recently, we are developing a novel CVD technology with a neutral particle beam (NPB) source, named as neutral beam assisted CVD (NBaCVD), which controls the energy of incident neutral particles in the range of 1~300eV in order to enhance the atomic activation and crystalline of thin films at low temperatures. During the formation of the nc-/pm-Si thin films by the NBaCVD with various process conditions, NPB energy directly controlled by the reflector bias and effectively increased crystal fraction (~80%) by uniformly distributed nc grains with 3~10 nm size. In the case of phosphorous doped Si thin films, the doping efficiency also increased as increasing the reflector bias (i.e. increasing NPB energy). At 330V of reflector bias, activation energy of the doped nc-Si thin film reduced as low as 0.001 eV. This means dopants are fully occupied as substitutional site, even though the Si thin film has nano-sized grain structure. And activated dopant concentration is recorded as high as up to 1020 #/$cm^3$ at very low process temperature (< $80^{\circ}C$) process without any post annealing. Theoretical solubility for the higher dopant concentration in Si thin film for order of 1020 #/$cm^3$ can be done only high temperature process or post annealing over $650^{\circ}C$. In general, as decreasing the grain size, the dopant binding energy increases as ratio of 1 of diameter of grain and the dopant hardly be activated. The highly doped nc-Si thin film by low-temperature NBaCVD process had smaller average grain size under 10 nm (measured by GIWAXS, GISAXS and TEM analysis), but achieved very higher activation of phosphorous dopant; NB energy sufficiently transports its energy to doping and crystallization even though without supplying additional thermal energy. TEM image shows that incubation layer does not formed between nc-Si film and SiO2 under later and highly crystallized nc-Si film is constructed with uniformly distributed nano-grains in polymorphous tissues. The nucleation should be start at the first layer on the SiO2 later, but it hardly growth to be cone-shaped micro-size grains. The nc-grain evenly embedded pm-Si thin film can be formatted by competition of the nucleation and the crystal growing, which depend on the NPB energies. In the evaluation of the light soaking degradation of photoconductivity, while conventional intrinsic and n-type doped a-Si thin films appeared typical degradation of photoconductivity, all of the nc-Si thin films processed by the NBaCVD show only a few % of degradation of it. From FTIR and RAMAN spectra, the energetic hydrogen NB atoms passivate nano-grain boundaries during the NBaCVD process because of the high diffusivity and chemical potential of hydrogen atoms.

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GC-MS 를 이용한 하천수 중 Bisphenol계 화합물의 동시분석 및 모니터링 (Simultaneous Determination and Monitoring of Bisphenols in River Water using Gas Chromatography-Mass Spectrometry)

  • 김지현;최정희;강태우;강태구;황순홍;심재한
    • 한국환경농학회지
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    • 제36권3호
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    • pp.154-160
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    • 2017
  • 본 연구는 하천수 중 bisphenol계 화합물 종 6 (BPA, BPB, BPC, BPE, BPF, BPS)을 동시분석하기 위하여 GC-MS를 이용하였다. 또한 최적의 전처리 방법을 확립하고자 SPE 및 LLE법을 이용하여 표준시료로부터 검량선의 직선성, MDL, LOQ, 정확도 및 정밀도를 비교하였다. SPE 및 LLE 전처리 방법에 의한 MDL은 각각 $0.0005{\sim}0.0234{\mu}g/L$$0.0037{\sim}0.2034{\mu}g/L$, LOQ는 각각 $0.0015{\sim}0.0744{\mu}g/L$$0.0117{\sim}0.6477{\mu}g/L$, 검량선의 결정계수($r^2$)는 모두 0.9969이상 정확도는 각각 93.2~108%와 97.4~120%, 정밀도는 각각 1.7~4.6%와 0.7~6.5%범위로 만족한 정도관리 결과를 얻었다. 하지만 SPE법에 의한 MDL 및 LOQ 값은 LLE법보다 약 4~45배 정도 높은 감도를 보였고, 특히 BPA의 경우는 다른 화합물들보다 45배 정도 높았다. 따라서, 본 연구에서는 SPE법을 적용하여 하천수 시료를 분석하였고, 조사지점은 본류 7개, 지류 6개, 하수종말처리장 2개 지점을 선정하였다. Bisphenol계 화합물 중에서 BPB, BPC, BPE, BPF 및 BPS는 모두 불검출 되었으나, BPA 농도는 $0.0095{\sim}0.2583{\mu}g/L$ 범위로 본류 $0.0166{\sim}0.0810{\mu}g/L$, 지류 $0.0095{\sim}0.2583{\mu}g/L$, 하수종말처리장$0.0352{\sim}0.1217{\mu}g/L$으로 미량 수준이었다.

수정 대혈관 전위 환자에서 예후에 영향을 주는 인자들에 대한 중기적 고찰 (Evaluation of Prognostic Factors in Corrected Transposition of the Great Arteries at Mid-term Follow-up)

  • 송영환;권혁주;김기범;강수정;배은정;노정일;윤용수;이정렬;김용진;노준량
    • Clinical and Experimental Pediatrics
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    • 제46권2호
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    • pp.154-161
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    • 2003
  • 목 적 : 수정 대혈관 전위 환자에서는 동반 심장 기형, 우심실 기능, 삼첨판 판막 기능, 부정맥 등이 예후에 영향을 주는 것으로 알려져 있다. 이 연구에서는 중기간의 관찰을 통해 여러 예후 인자들을 비교 분석하였다. 방 법 : 서울대학교병원에서 C-TGA로 진단 받은 94명을 대상으로 후향적 임상 기록 고찰을 시행하였다. 대상 환자들은 남아가 58명, 여아가 36명이었고, 추적 관찰 시 최종 평균 연령은 $12{\pm}9$세였으며, 평균 추적 관찰 기간은 $9{\pm}6.4$년이었다. 결 과 : 대상 환자 94명 중에 심장 수술은 72명이 시행 받았고, 고전적 교정술이 55례, 해부학적 교정술이 17례였다. 동반된 심장 기형(삼첨판 역류, 폐동맥 협착이나 폐쇄, 심실 중격 결손, 임상군), 심장 수술 여부와 종류, 완전 방실 전도 차단을 예후인자로 설정하였고, 예후 인자들 중에서 삼첨판 역류, 폐동맥 협착, 심실 중격 결손은 중등도 이상인 경우만 양성으로 채택하였다. 본 연구에서는 삼첨판 역류만이 생존율에 영향을 주는 예후인자였으며, Ebstein 기형과 고도 방실 전도 차단이 삼첨판 역류와 연관성이 있었다. 삼첨판 부전이 있는 환자의 20년 생존율은 35%로, 없는 환자 77%에 비교해서 유의한 차이를 보였고, 수술 직후 사망을 제외한 소그룹 분석에서도 삼첨판 부전이 있는 경우와 없는 경우의 20년 생존율이 각각 48%와 87%로 유의한 차이를 보였다. 20년 생존율 분석과 삼첨판 역류와의 연관성 분석에서 고전적 교정술과 해부학적 교정술간에 유의한 차이는 없었다. 결 론 : 삼첨판 부전은 수정 대혈관 전위 환자의 중요한 예후인자이며, Ebstein 기형과 방실 전도 장애가 삼첨판 부전에 영향을 줄 수 있다. 이 밖에 심장 수술, 동반 심기형 등 다른 예후인자에 대한 정확한 평가를 위해서는 장기적인 추적 관찰이 필요하다.

태양열 물펌프의 운전 자동화 설계 (Design of the Condenser and Automation of a Solar Powered Water Pump)

  • 김영복;손재길;이승규;김성태;이양근
    • 한국축산시설환경학회지
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    • 제10권3호
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    • pp.141-154
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    • 2004
  • 자연에너지인 태양열을 동력원으로 하여 구동되는 물펌프는 물이 많이 필요한 여름철에 과 열원인 태양에너지가 강하므로 매우 이상적인 장치라 할 수 있다. 본 연구에서는 태양열 물펌프의 자동화운전을 실현하고자 작동물질의 압력변화를 감지하여 자동 운전되도록 하였으며, 이에 필요한 제어논리를 개발하고 회로론 구성하였다. 실험에서는 장치를 제작. 실험, 분석하였고 분석항목은 양수량과 효율, 압력, 온도를 분석하였다. 또한 자동화에 필수적인 응축기 진공을 위한 응축기의 최소 전열면적을 설계하였으며, 그 결과를 정리하면 다음과 같다. 1. 복사에너지를 동력으로 변환하여 물을 양수할 수 있었고, 자동화 제어회로에 의해 사이클을 반복할 수 있었다. 2 양수는 60분 동안에 13사이클을 수행하였으며, 사이클 당 소요시간은 약 4.9분이었다. 총 양수량은 69,200cc, 사이클 당 평균 5,320cc를 양수하였다. 이 과정동안 장치의 열효율은 $0.030\%$로 나타났다. 3. 실험과정에서 기액 분리탱크 내의 작동물질 증기의 온도는 물탱크로 증기를 배출하기 전후에 따라 약 $41\~49^{\circ}C$ 범위에 있었으며, 상당히 균일하게 변동하고 있었다. 물탱크와 공기탱크내의 온도는 약 $30^{\circ}C$ 정도 부근에서 유지되고 있었으며, 응축기 냉각수공급온도는 실험기간 중 $10\~13^{\circ}C$ 범위를 나타내었다. 응축기 출구온도는 $14\~17^{\circ}C$ 정도로서 응축기 냉각수의 입출구 온도차는 실험초기를 제외하면 약 $4^{\circ}C$ 전후로 나타났다 4. 기액 분리탱크 내의 압력은 자동화 프로그램 된 범위인 150$\~$450hPa(gauge)를 매우 정확하게 유지하였으며, 공기탱크내의 압력은 약 1200hPa로 나타났다. 응축기내의 압력은 약 600hPa로서 진공을 잘 유지함으로서 사이클을 반복하는데 문제가 없었다. 5. 한국의 전국 하루 평균 3.488kWh/($m^2{\cdot}day$)의 태양에너지를 기준으로 장치의 열효율이 $0.1\%$를 적용하고 전 양정을 10m로 보면 태양열복사 단위면적 $m^2$ 당 약 128kg의 물을 양수할 수 있을 것으로 예상된다.

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유도 맞잡기 타입에 따른 허벅다리걸기의 Kinematic 분석[I] (A Kinematic Analysis of Uchi-mata(inner thigh reaping throw) by Kumi-kata types in Judo)

  • 김의환;조동희;권문석
    • 한국운동역학회지
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    • 제12권1호
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    • pp.63-87
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    • 2002
  • The purpose of this study was to analyze the kinematic variables when Uchi-mata(inner thigh reaping throw) performing by Kumi-kata(engagement position, basic hold) types A, B(A: grasping part-behind neck lapel, B: chest lapel) in Judo with three dimensional analysis technique DLT method by videography. The subjects were four male judokas who have been training in Yong-In University(YIU), on Korean Representative level and Uchi-mata is their tokui-nage(favorite technique), the throwing form was filmed on two S-VHS 16mm video camera( 30frame/sec. Panasonic). Kinematic variables were temporal, posture, and COG. The data collection was performing by Uchi-mata. Six good trials were collected for each condition (type A, B) among over 10 trials. The mean values and the standard deviation for each variable were obtained and used as basic factors for examining characteristics of Uchi-mata by Kumi-kata types. The results of this analysis were as follows : 1) Temporal variables The total time elapsed(TE) by Uchi-mata of types A, B were 1.45, 1.56 sec. respectively. Types A shorter than B. 2) Posture variables In performing of Uchi-mata, the range of flexion in type A, left elbow was $45^{\circ}$ and B was $89^{\circ}$ from Event 2(E2) to Event 6(E6). Type A and B were quite different in right elbow angle in Event1(E1). Left shoulder angle of type A was extended and type B was flexed in E4. Both types right shoulder angles were showed similar pattern. Also both hip angles(right/left) were showed similar pattern. When type A performed Uchi-mata the knee-angle of supporting foot showed $142^{\circ}$in the 1st stage of kake phase[KP], and extended to $147^{\circ}$in the 2nd stage of KP. And the foot-ankle angle of supporting foot showed $83^{\circ}$in the 1st stage of KP, and extended to $86^{\circ}$in the 2nd stage of KP. moreover, The knee angle of attacking foot showed $126^{\circ}$in the 1st stage of KP, and extended to $132^{\circ}$in the 2nd stage of KP, and the foot-ankle angle of attacking foot showed $106^{\circ}$in the 1st stage of KP, and extended to $121^{\circ}$in the 2nd stage of KP. When type B performed Uchi-mata the knee-angle of supporting foot showed $144^{\circ}$in the 1st stage of KP, and extended to $154^{\circ}$in the 2nd stage of KP. And the foot-ankle angle of supporting foot showed $83^{\circ}$in the 1st stage of KP, and extended to $92^{\circ}$in the 2nd stage of KP. moreover, The knee angle of attacking foot showed $132^{\circ}$in the 1st stage of KP, and extended to $140^{\circ}$in the 2nd stage of KP, and the foot-ankle angle of attacking foot showed $103^{\circ}$in the 1st stage of KP, and extended to $115^{\circ}$in the 2nd stage of KP. During Uchi-mata performing, type A showed pulling pattern and type B showed lift-pulling pattern. As Kumi-kata types, it were different to upper body(elbow, shoulder angle), but mostly similar to lower body(hip, knee, ankle angle) on both types. 3) C. O. G. variables When the subjects performed Uchi-mata, COG of type A, B up and down in vertical aspect was 71cm, 73.8cm in height from the foot in the 2nd stage of KP. As Kumi-kata types, it were different on medial-lateral direction aspect but weren't different in Kuzushi phase on vertical direction aspect.

맥주박을 첨가한 섬유질 배합사료가 번식흑염소의 영양소 이용율에 미치는 영향 (Effects of Total Mixed Ration with Wet Brewer's Grain on Nutrient Utilization in Breeding Korean Native Goats)

  • 최순호;황보순;김상우;상병돈;김영근;조익환
    • 한국초지조사료학회지
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    • 제26권3호
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    • pp.147-154
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    • 2006
  • 본 연구는 섬유질 배합사료에 맥주박 수준을 달리 첨가하여 번식 흑염소의 사료 및 영양소 섭취량, 영양소 소화율 및 질소 축적율에 미치는 영향을 조사하여 번식 흑염소의 사료로서 맥주박의 사료가치를 평가하고자 실시하였다. 공시축은 번식 흑염소 12두를 4처리구(관행사료구, 맥주박 20, 30 및 40% 첨가구)로 나누어 처리구당 3두씩 대사케이지에 완전임의 배치법으로 배치하여 시험을 실시하였으며 그 결과는 다음과 같다. 맥주박 첨가 수준별 섬유질 배합사료의 일반 조성분은 건물 함량이 $61.46{\sim}65.81%$, 조단백질 함량은 $14.42{\sim}15.59%$의 수준이었으며, ADF 와 NDF 함량은 $28.32{\sim}28.52$$53.46{\sim}54.16%$로 나타나 맥주박 첨가 비율에 따른 섬유소 함량 의 차이는 없었으나, NFC 함량은 맥주박 첨가 비율이 높을수록 NFC 함량이 낮아졌다. 건물 섭취량은 맥주박을 20% 첨가하였을 때 대조구보다 다소 높은 경향이었다. 조단백질과 가소화 조단백질 섭취량은 맥주박 첨가구가 대조구 보다 높은 경향을 나타내었고, NFC 섭취량과 가소화 NFC 섭취량은 대조구가 맥주박첨가구보다 높은 경향이었고 맥주박첨가수준이 높을수록 낮아지는 경향이었다. 건물, ADF, NDF 및 NFC 소화율은 대조구가 맥주박 첨가구 보다 높았으며 (p<0.05), 조단백질 소화율은 맥주박 첨가구가 대조구보다 높은 경향이었고 질소 축적율은 맥주박첨가구가 대조구보다 다소 높은 경향이었다.

일 지역 성인의 고혈압 유병률 및 관리 실태 (A Study on the Prevalence Rate of Hypertension and the Actual Conditions of Control)

  • 김현옥
    • 지역사회간호학회지
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    • 제10권1호
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    • pp.154-172
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    • 1999
  • In order to analyse the prevalence rate of hypertension and the actual conditions of control, we selected five districts out of eleven eups and myuns in Chinan Country. We administered structured questionaries to 309 adults above the age of 40, computerized the data using SPSS - PC+. More than 40.1% of adults over 40 in Chinan County have health disorders ranging from high blood pressure to hypertension including alert high blood pressure at 36.2%, relatively high. Among general characteristics, differences in the rate of hypertension were influenced by age, occupation and places of residence. Over 71 who are engaged in agriculture, who don't have jobs, who reside in Sungsu, Jungchun, Chinan-eup all have higher hypertension rates than other groups. Accordingly, the control of hypertension should be focused on these people. As a result of the control of blood pressure, the survey showed 93.0% of the subjects were checked mainly at hospitals clinics, health centers subhealth centers and community health posts more than once a year, relatively high level of blood pressure management. However, the difference between their blood pressure measurements at ordinary times and the level of blood pressure at the time of research was quite considerable. Only 47.3% of the subjects diagnosed with high blood pressure and 70.3% of the subjects with normal blood pressure recognized their blood pressure accurately 52.7% of the subjects diagnosed with high blood pressure showed errors in understanding their blood pressure at normal times. Because these errors can cause problems in the control of blood pressure, proper management should be executed through a systematic examination. As a result of the high blood pressure control condition, the average period of hypertension was 74.5( ${\pm}92.8$) months, 92.3% of the subjects were diagnosed with high blood pressure at hospitals clinics, health centers subhealth centers community health posts, but only 29.5% were examined after a general check up on high blood pressure was completed. 70.5% were diagnosed with high blood pressure only after measuring their blood pressure. 14.1% of the subjects were hospitalized because of falls influenced by high blood pressure. 33.3% attended hospitals and health centers regularily for medical treatment and this shows how low the rate of the control of blood pressure. Most people did not undergo medical treatment, because they had no painful symptoms (46.7%), they didn't need to take the medicine(28.9%), or they forget to take the medicine(20.0%). These problems in the control of hypertension were discovered in the process of diagnosing high blood pressure at health medical institutions. Many people did not recognize the need for consistent control of blood pressure. That is, although the diagnosis for high blood pressures performed at hospitals clinics, health centers subhealth centers and community health posts, was 92.3%, more than 70.5% of the subjects were not examined completely with regard to blood pressure. Accordingly, heath medical institutions must diagnose high blood pressure not only by only measuring blood pressure but also by using systematic process of examination. As for the people diagnosed with high blood pressure, one should perform consistent medical approaches and help them to recognize the importance of the continuous control of blood pressure through subject-oriented education. Problems the subjects experienced were the following numbness in the limbs easily paralyzed stitches in their shoulders which felt painful, stiff necks, occiputs felt heavy, headaches when they got up in the morning, felt dizzy when standing and moving their heads and poor eyesight. The rate of knowledge related to high blood pressure was 78.7 points, comparatively low. Whether they had normal blood pressure or hypertension made no difference. These results are not desirable. Adult-oriented education forgot the prevention and management of high blood pressure should be implemented. Hypertensive-oriented education should be especially reinforced. Because there was a difference in the level of knowledge according to age, academic career, occupation or place of residence, education related to hypertension should be intensified and focused on those over the age of 71 those who did not attend school, those who do not have jobs and are engaged in agriculture and residents living in Bugui, Jungchun regions. The degree of healthy life practice in hypertensives is poor, particularly weight control, as opposed to people who have normal blood pressure. It makes no difference in smoking, the amount of daily smoking, drinking, the control of salt because each result means that they are not practicing healthy life or modifying their life-style. The development and programs to improve a healthy life should be executed.

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비육돈에 있어 황기, 인삼, 양파 혼합물의 급여가 성장 밑 도체 특성에 미치는 영향 (Effects of Dietary Astragalus membranaceus, Ginseng and Onion Complex on Growth Performance and Carcass Characteristics in Finishing Pigs)

  • 홍종욱;김인호;김지훈;권오석;이상환;서완수;김철;김을상;정윤화
    • 한국식품영양과학회지
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    • 제31권1호
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    • pp.149-154
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    • 2002
  • 본 연구의 목적은 생약제 및 양파 혼합물의 급여가 비육돈의 성장 및 도체 특성에 미치는 영향을 평가하기 위하여 실시하였다. 3원 교잡종(Durox$\times$Yorkshire$\times$Landrace) 비육돈 72두을 공시하였으며 시험개시시의 체중은 체중은 75.66$\pm$1.86 kg 이었다. 처리구로는 옥수수-대두박 위주의 식이에 NRC(12)의 영양소 요구량에 따라 처리한 구(Control: 기초식이), 대조구 식이내 생약제 및 양파 혼합물을 0.25% 첨가한 구(AGO 0.25: 기초식이+0.25% 생약제 및 양파 혼합물), 대조구 식이내 생약제 및 양파 혼합물을 0.50% 첨가한 구(AGO 0.50: 기초식이 + 0.50% 생약제 및 양파 혼합물)로 3개 처리를 하여 처리당 4반복, 반복당 6마리씩 완전임의 배치하였다. 본 사양시험에 사용한 생약제 및 양파 혼합물은 인삼, 황기 그리고 양파 분말을 함유한 것을 사용하였다. 전체 시험기간 동안, 생약제 및 양파 혼합물의 첨가수준이 증가함에 따라 식이효율 및 등지방 두께가 증가하는 경향을 나타내었으나 유의적인 차이는 보이지 않았다(p>0.05). 도체등급에 있어서는 생약제 및 양파 혼합물의 첨가수준이 증가함에 따라 A등급 출현율이 높은 것으로 평가되었다(linear effect, p<0.01). 대조구 및 AGO 0.50 처리구와 비교하여 AGO 0.25 처리구가 혈청내 총 콜레스테롤 및 LDL+VLDL 콜레스테롤 농도가 낮은 것으로 평가되었으나 유의적인 차이는 보이지 않았다(p>0.05). 도축한 돈육의 등심부의 육색에 있어서 L-$^{*}$ , a-$^{*}$ , b-$^{*}$ 값에 있어서도 유의적인 차이를 보이지 않았다(p>0.05). 생약제 및 양파 혼합물 급여에 따른 증체량 개선 효과로 인해 증체당 식이비는 대조구가 830원, AGO 0.50 처리구가 813원으로 대조구와 비교하여 2.05%의 식이비 절감 효과를 나타내었다. 결론적으로 비육돈 식이내 생약제 및 양파 혼합물의 첨가가 성장 촉진을 갖는 것으로 사료되나 도체특성에는 영향을 미치지 않는 것으로 판단된다.

임플란트 식립 부위의 골밀도 평가에 관한 연구 (The study of bone density assessment on dental implant sites)

  • 박수원;장수미;최병환;손한나;박봉찬;김창환;손장호;성일용;이지호;조영철
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제36권5호
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    • pp.417-422
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    • 2010
  • Introduction: Bone density is one of the important factors for the long term success of endosseous implants. The bone density varies from site to site and from patient to patient. A preoperative evaluation of the bone density is quite useful to oral surgeons for planning dental implantation. More accurate information on the bone density will help surgeons identify suitable implant sites, thereby increase the success rate of dental implantation. This study examined the correlation between the bone density measured preoperatively by computed tomography (CT) and the implant primary stability measured by resonance frequency analysis. Furthermore, the effects of the implant sites, gender, age and generalized systemic disorder patients on the bone density and primary implant stability were examined. Materials and Methods: One hundred and fourteen patients were selected. None of the patients had undergone a tooth extraction or bone graft history in the previous year. Preoperatively, the patients underwent CT scanning to evaluate the Hounsfield unit (HU), and resonance frequency analysis (RFA) was used to evaluate the implant primary stability at the time of implant installation. All implants were 4.0 mm diameter and 11.5 mm length US II. All patients were recorded and the HU and implant stability quotient (ISQ) value were evaluated according to the sites, gender and age. Results: The highest HU values were found in the mandibular anterior site ($827.6{\pm}151.4$), followed by the mandibular molar site ($797{\pm}135.1$), mandibular premolar site ($753.8{\pm}171.2$), maxillary anterior site ($726.3{\pm}154.4$), maxillary premolar site ($656.7{\pm}173.8$) and maxillary molar site ($621.5{\pm}164.9$). The ISQ value was the highest in the mandibular premolar site ($81.5{\pm}2.4$) followed by the mandibular molar site ($80.0{\pm}5.7$), maxillary anterior site ($77.4{\pm}4.1$), mandibular anterior site ($76.4{\pm}11.9$), maxillary premolar site ($74.2{\pm}14.3$) and maxillary molar site ($73.7{\pm}7.4$). The mean HU and ISQ value were similar in females and males. (HU: P=0.331, ISQ: P=0.595) No significant difference was also found in the age group respectively. However, the correlation coefficients between the variables showed a closed correlation between the HU and ISQ value. Conclusion: These results showed close correlation between the bone density (HU) and primary stability value (ISQ) at the time of implant installation (Correlation coefficients=0.497, P<0.01). These results strengthen the hypothesis that it might be possible to predict and quantify the initial implant stability and bone density from a presurgical CT diagnosis.

대학병원 의료종사자들의 병원감염에 대한 예방지침 실행수준과 관련요인 (Compliance Level of Universal Precautions to Hospital Infection and related factors of Health Care Workers in a University Hospital)

  • 유미종
    • 한국직업건강간호학회지
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    • 제7권2호
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    • pp.143-154
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    • 1998
  • The purpose of this research is to suggest basic materials for the practical infection precaution program to protect health care workers from hospital infection by grasping their compliance level of Universal Precautions and examining the factors affecting them. The number of the health care workers we studied were 486, including the doctors, the nurses, and the lab technicians who were working in a university hospital. The period of this research was from Aug. 18th, 1997 to Aug. 30th, 1997. The method of the study was to measure the compliance level of Universal Precautions with the item of "Universal Precautions" established by CDC in 1987, and examine the questionnaire of 52 questions dividing related factors into socio-populational, individual, socio-psychological and organizational management ones. The data was analyzed by t-test. ANOVA, and chi-square test. The results were as follows : 1. An the compliance level of Universal Precautions, hand washing had the highest score(85.4%), and doctors(18.9%), nurses(44.0%), and lab technicians(7.6%), had a low compliance level in the safe handling of an injection syringe, and item not to handle patients and their samples when the subject suffered from dermatitis or injury had the lowest score of 17.1%. 23.3% of them said that they wear protection gown, goggles and mask. 2. Female's Compliance level of Universal Precautions Was higher than male. 3. The health care workers who had high recognition on Universal Precautions got significantly higher compliance level of Universal Precautions than those have low recognition on Universal Precautions(P<0.001). 4. The health care workers experienced a needle stick injury had a significantly higher compliance level of Universal Precautions than those who had not(P<0.000). 5. The health care workers who had infection protection education got a significantly higher compliance level of Universal Precautions than those who didn't(P<0.000). 6. The health care workers who had a firm belief in the effect of Universal Precautions got a higher compliance level of Universal Precautions than those who didn't. 7. The health care workers who had less conflicts between treating patient arid protecting them-selves got a higher compliance level of Universal Precautions than others with many conflicts. 8. The health care workers who had a high score in organizational management factors got a significantly higher compliance level of Universal Precautions than those with a low score(P<0.000). 9. Only 16.9 percent of the all respondents(82 in number) answered that they knew well or a little about the Universal Precautions, which is very low rate of recognition. 10. The variables which affected the score in organizational management factors were age, sex, education period, work experience, the kind of work, recognition on Universal Precautions, the experience of needle stick injury, revealing dangerous circumstance related to infection, and training on precaution again infection. According to the result above, compliance level of Universal Precautions showed high correlation with sex, the recognition on Universal Precautions, the experience of needle stick injury, training on precaution against infection, the belief in the effect of Universal Precautions, the recognition degree of conflicts and organizatinal management factors. These results could be used as the basic materials for the developing infection protection programs. Also, There should have a systematic training course to elevate a effective compliance level of Universal Precautions as well as the manageeent of infection protection programs.

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