• Nuclear Engineering and Technology
• /
• 제7권1호
• /
• pp.9-14
• /
• 1975

슬레이트에 단량체 methyl methacrylate를 침투시키고 감마선 및 촉매 가열법으로 중합시켜 슬레이트-플라스틱 복합체를 제조하였다. 제품의 성질은 휨강도, 내수성 내산성등에 현저한 증가를 나타내었으며, 중합조건에 의한 차이점도 그 원인과 함께 비교 검토하였다.

• Journal of Korean Neurosurgical Society
• /
• 제66권3호
• /
• pp.263-273
• /
• 2023

While the survival rate of preterm infants has increased dramatically over the last few decades, intraventricular hemorrhage and subsequent hydrocephalus remain major unsolved problems in neonatal intensive care. Once intraventricular hemorrhage occurs, severe neurological sequelae are inevitable. Treatment of this complicated pathology and achievement of favorable neurofunctional outcomes in fragile infants are crucial challenges for pediatric neurosurgeons. Fibrinolytic therapy, which chemically dissolves hematoma, is a promising and useful treatment method. In this paper, the historical background of fibrinolytic therapy for post-intraventricular hemorrhagic hydrocephalus in preterm infants is reviewed and a recent method of fibrinolytic therapy using urokinase is introduced.

• 한국환경농학회지
• /
• 제19권4호
• /
• pp.324-327
• /
• 2000

저선량 조사한 대두종자의 초기생육과 대두 유식물체의 후속고선량에 대한 방사선 감수성 변화를 알아보고자 저선량 0, 4, 8, 12, 20 Gy를 조사하여 재배한 대두 유식물체에 ${\gamma}$선 50, 100, 200 Gy를 조사한 후 생육상황을 관찰하였다. 저선량 조사에 의해 대두 신규종자의 발아율 증가효과는 없었으나 작물 생장 증대효과는 있었으며 저선량 8 Gy 조사구가 가장 효과적이었다. 대두유식물체의 고선량 방사선에 의한 생육장해는 사전 저선량조사에 의해 크게 감소되었으며 저선량 조사에 의한 고선량 방사선 저항성 증가는 8 Gy와 20 Gy조사에서 가장 효과적이었다.

• 한국정보과학회논문지:정보통신
• /
• 제30권6호
• /
• pp.695-704
• /
• 2003

웨이블릿 기반 비디오는 DCT 기반 비디오에 비해 전송오류에 더 민감하다. 즉, 어떤 프레임의 부대역에 오류가 발생하면 같은 프레임의 다른 부대역뿐 아니라 그 프레임을 참조하는 이후 프레임의 복원에도 영향을 주어 비디오의 화질이 감소하게 된다. 본 논문에서는 프레임 간 참조를 수행하는 웨이블릿 비디오의 오류 전파를 줄이기 위해 프레임 내 참조 기법을 제안한다. 제안된 기법에서는 LL 부대역을 제외한 나머지 부대역에서 같은 프레임의 하위 부대역을 참조하여 다른 프레임으로의 오류전파를 줄인다. 무선 채널에서의 비트 에러 패턴을 이용하여 모의실험을 수행한 결과 화면의 움직임이 빠른 비디오에서는 제안된 기법의 성능이 압축율에 관계없이 우수하였으며 화면의 움직임이 거의 없는 비디오에서는 비트율이 높은 경우에 성능이 높은 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제3권2호
• /
• pp.75-83
• /
• 1990

An experiment was conducted with three ruminally and intestinally cannulated non-lactating cows of Finnish Ayrshire breed, to assess the ruminal degradation characteristics of oat (Avena sativa), rye (Secale cereale) and rice (Oryza sativa) straw by the nylon bag technique, and the subsequent post-ruminal degradation of their rumen-undegraded residues by using the mobile bag technique, respectively. The straw samples were untreated or treated with aqueous $NH_3$ or with urea solution in cold or hot water. The untreated straw samples were milled or chopped, and the treated straw samples were chopped. The constant values a, b, and c were computed according to the exponential equation, where a = intercept of degradation curve at time 0, b = potentially degradable material, c = rate of degradation of band (a+b) = maximum potential degradability (asymptote). It was found that nitrogen contents of chemically treated straw were markedly increased by both $NH_3$ and urea treatments. Milling the samples attributed to a remarkable loss at 0 h incubation time as compared to chopping of the respective samples. However, chemical treatment markedly improved the b value and the subsequent (a+b) values for dry matter, organic matter, neutral-detergent fiber, and acid-detergent fiber of the samples. Furthermore, temperature of the water used in the urea solutions was considered essential, since urea in hot water rather than in cold water seemed to enhance the overall degradability. The disappearance of rumen-incubated straw residues from the mobile bags ranged from 4.5 to 9.6% for the parameters measured. On average, the OM disappearance from bags was clearly higher for the residues of urea treated straw compared to those of ammonia treated straw, but the disappearance of NDF tended, however, to be higher on the ammonia treatment.

• 한국임상수의학회지
• /
• 제23권4권
• /
• pp.453-457
• /
• 2006

This study determined the effects of several reproductive factors at prostaglandin $F_{2{\alpha}}\;(PGF_{2{\alpha}})$ administration on the subsequent estrous exhibition and conception. Three hundreds and twenty six dairy cows in seven dairy herds received a 25 mg $PGF_{2{\alpha}}$ after confirming the presence of corpus luteum (CL) by ultrasonography, and the cows exhibited estrus within 7 days following $PGF_{2{\alpha}}$ administration were artificially inseminated (AI). Two hundreds cows among the 326 cows received additional ultrasonography at $PGF_{2{\alpha}}$ administration to measure the diameters of the largest follicle and CL on ovaries, and blood samples collected from the cows were analyzed for serum progesterone (P4) level. Cow parity, days open, body condition score (BCS), season and herd variables were recorded. Of the treated 326 cows, 171 cows (52.5%) showed estrus within 7 days after treatment, and the conception rate following AI was 37.4% (64/171). There were significant differences on the estrous exhibition ($31.3{\sim}65.8%$, p<0.01) and conception rates ($23.1{\sim}66.7%$, p<0.05) among the herds, while cow parity, days open, BCS and season did not affect the subsequent estrous exhibition and conception rates. The diameters of the largest follicle and CL on ovaries, and serum P4 level at the $PGF_{2{\alpha}}$ administration were not related to the subsequent estrous exhibition and conception. The results indicate that the improved outcomes of synchronization of estrus using a single $PGF_{2{\alpha}}$ administration may be related to the appropriate management of the herd.

• Advances in pediatric surgery
• /
• 제4권1호
• /
• pp.16-26
• /
• 1998

Parenteral nutrition has been an essential part of postoperative care of neonates requiring major surgery who are unable to tolerate enteral feeding for long periods during the postoperative period. However, TPN via central venous catheters(central TPN), used in increasing trend, still presents significant morbidity. To find out whether TPN via peripheral veins(peripheral TPN) could be used as a viable alternative for postoperative parenteral nutrition in neonates, a clinical study was carried out by a retrospective analysis of 53 neonates subjected to peripheral TPN for more than 7 days after surgery. Operations consisted of procedures for esophageal atresia with tracheoesophageal fistula, gastroschisis and omphalocele. Surgery was performed at the Division of Pediatric Surgery, Department of Surgery, Hanyang University Hospitall, from 1983 to 1994. The mean total duration of TPN was 13.3 days (range; 7-58 days), the average daily total fluid intake was 117.6 ml/kg during TPN and 158.6 ml/kg during subsequent oral feeding. The average daily total calorie intake was 57.7 kcal/kg during full strength TPN and 101.3 kcal/kg during subsequent oral feeding. The mean urine output was maintained at 3.5 ml/kg/ hour during TPN and at 3.6 ml/kg/hour during subsequent oral feeding. The increment of body weight observed during TPN was 132 g in TEF, 53 g in gastroschisis and 3 g in omphalocele patients, while loss of body weight was not observed. The mortality rate was 5.7 %(3/53) and was related to the underlying congenital anomalies, not the TPN. The most common complication of peripheral TPN observed was laboratory findings suggestive of liver dysfunction in 23 cases(43.4 %) with no significant clinical symptom or signs in any case, transient pulmonary edema in one case, and generalized edema in one case. None of the major complications usually expected associated with central TPN were observed. The result of this study suggest that peripheral TPN can be used for adeguate postoperative nutritional support in neonates requiring 2 to 3 weeks of TPN.

• 한국임상수의학회지
• /
• 제24권3호
• /
• pp.337-341
• /
• 2007

This study determined the effect of postpartum intrauterine infusion of povidone-iodine solution on the subsequent reproductive performance in dairy cows. Six hundred and fifty-eight dairy cows that were around week 4 postpartum were randomly divided into two groups: (1) Cows in treated group received an intrauterine infusion of 100 to 150 ml 2% povidone-iodine solution (treated group, n=269), or (2) Cows that received no treatment were served as the controls (control group, n=389). The cows were bred at observed estrus more than 50 days after calving. Artificial insemination (AI) was done according to the a.m.-p.m. rule. The conception to AI was determined per rectum 60 days after AI by both ultrasonographical observation and manual palpation. The intervals from calving to first service and conception ($94.2{\pm}2.7$ and $144.1{\pm}4.1$ days vs. $88.0{\pm,}2.1$ and $143.5{\pm}4.6$ days, respectively), number of services per conception ($2.0{\pm}0.1$ vs. $2.1{\pm}0.1$), and cumulative pregnancy rates within 90 and 150 days postpartum (31.9 and 61.7% vs. 29.7 and 62.1%) did not differ between the control and treated groups (P>0.05), while conception rate at first service was lower (P<0.05) in the treated group (40.5%) than in the control group (49.4%). Additionally, we could not find any effect of intrauterine infusion of povidone-iodine solution according to cow parity or calving season on the reproductive performance. These results indicate that intrauterine infusion of povidone-iodine solution at week 4 postpartum does not affect the subsequent reproductive performance in dairy cows.

• 한국유체기계학회 논문집
• /
• 제4권3호
• /
• pp.53-61
• /
• 2001

Vortex type Fluidic Device(FD) which is installed at the bottom of Safety Injection Tank(SIT) controls the discharge flow rate from the tank. In case of loss of coolant accident the injection water flows into primary system in two steps; initial high flow rate for certain period of time and subsequent low flow rate. By two-step control of the discharge flow rate, FD can ensure the effective use of water in the tank. A small-scale FD has been tested to obtain a required flow characteristics maintaining full pressure and height of prototype, which are the major contributing parameters. Through the testing of many different arrangements of internal geometry of FD, most appropriate one was selected and its performance data was obtained. As characteristics of FD, time dependent Euler number, flow rate and pressure are presented and discussed. Also a method to predict the full size FD is presented.

• 한국기계가공학회지
• /
• 제3권1호
• /
• pp.28-37
• /
• 2004

An on-line monitoring system of endmill failure such as weal, chipping, and fracture is developed using AE, cutting force Characteristic variations of AE and cutting force signals due to endmill failure are identified as follows. When endmill fracture occurs, AE count rate shows a rapid Increase in conjunction with a subsequent decrease while a standard deviation of the principal cutting force Increases significantly. The increase of AE count rate precedes the Increase of standard deviation of principal cutting force. Chipping results in relatively small increase and decrease of AE count rate without any significant variation of the cutting force Gradual increase of AE count rate and mean principal cutting force are Identified to be related with the wear of cutter. A cutter fracture detection algorithm is developed based on the present results. The signals me normalized to enhance the applicability of the algorithm to Wide those of fresh cutters, and qualitative characteristics of AE signals encountered at the moment of fracture are employed. It is demonstrated that the algorithm can detect the cutter fracture successfully.