• 한국생산제조학회지
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• 제22권1호
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• pp.145-149
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• 2013

The performance of injection molding machine's control system, such as reproducibility, repeatability, etc, is widely studied nowadays. Since screw stroke, injection cylinder body pressure and barrel temperature are the most important terms of injection unit, interval linearity and repeatability to each parameter are analyzed here. Barrel temperature is analyzed according to the repeatability of the thermocouple at $150^{\circ}C$, $210^{\circ}C$, $300^{\circ}C$ using a precise oven. The result temperature is within ${\pm}0.5^{\circ}C$ Through the reliability evaluation of the most important terms of injection unit, the method of evaluating the linearity and repeatability is proposed and verified.

• 한국수정란이식학회지
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• 제26권2호
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• pp.91-96
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• 2011

The purpose of this study was to evaluate the effects of days open on subsequent reproductive performance following to estrus synchronization in the 114 lactating dairy cows. The animals were divided into two groups according to the time of estrus synchronization; viz, ${\leq}$ 85 days, and > 85 days postpartum, respectively. The estrus synchronization protocol consisted of insertion of a controlled internal drug release (CIDR) device containing 1.9 g progesterone with an injection of 250 ${\mu}g$ gonadorelin (Day 0), an injection of $PGF_2{\alpha}$ and removal of the device on Day 7, an injection of 250 ${\mu}g$ GnRH on Day 9, and TAI 17 h later. Pregnancy diagnosis was determined at 30 to 60 days after TAI using both ultrasonography and rectal palpation. The body condition score (BCS) gradually increased over the postpartum period. In estrus synchronized cows until 85 days, conception rate on first service, number of service per conception, interval from estrus synchronization to conception, and interval from calving to conception were not significantly different among two farms (P>0.05). In estrus synchronized cows after 85 days postpartum, conception rate on first service, number of service per conception and interval from calving to conception were significantly different ($P{\leq}0.05$) between herds A and B (26.8 vs 50.0%; $2.1{\pm}1.35$ vs $1.37{\pm}0.54$ times, $237.3{\pm}97.8$ vs $164.7{\pm}69.3$ days, respectively). In estrus synchronized cows after 85 days postpartum interval from estrus synchronization to conception was greater (P<0.01) in herd B than in herd A ($63.6{\pm}57.4$ vs $26.1{\pm}24.9$). These results indicate that the time of estrus synchronization for maximized the reproductive performance is before 85 days postpartum and feeding and management is important factor for high reproductive performance.

• 한국분무공학회지
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• 제14권1호
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• pp.8-14
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• 2009

This paper present the diesel fuel spray evolution and atomization performance in a multi-hole nozzle in terms of injection rate, spray evolutions, and mean diameter and velocity of droplets in a compression ignition engine. In order to study the effect of split injection on the diesel fuel spray and atomization characteristic in a multi-hole nozzle, the test nozzle that has two-row small orifice with 0.2 mm interval was used. The time based fuel injection rate characteristics was analyzed from the pressure variation generated in a measuring tube. The spray characteristics of a multi-hole nozzle were visualized and measured by spray visualization system and phase Doppler particle analyzer (PDPA) system. It was revealed that the total injected fuel quantities of split injection are smaller than those of single injection condition. In case of injection rate characteristics, the split injection is a little lower than single injection and the peak value of second injection rate is lower than single injection. The spray velocity of split injection is also lower because of short energizing duration and small injection mass. It can not observe the improvement of droplet atomization due to the split injection, however, it enhances the droplet distributions at the early stage of fuel injection.

• Asian-Australasian Journal of Animal Sciences
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• 제22권6호
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• pp.774-780
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• 2009

The objectives of this study were to test the efficacy of induction of estrus and determine the timing of ovulation in relation to preovulatory LH and estrogen surges in cycling Murrah buffaloes subjected to Heatsynch protocol (GnRH-$PGF_2{\alpha}$-Estradiol benzoate). In experiment 1, the buffaloes (n = 10) were treated with Heatsynch protocol and observed for estrus and ovulation. In experiment 2 and 3, 30 cycling Murrah buffaloes were used to investigate the efficacy of Heatsynch protocol in terms of conception rates in summer (experiment 2) and winter (experiment 3) seasons. Fixed time A.I. was performed in all the buffaloes at 48 and 60 h post-estradiol benzoate (EB) injection. All buffaloes responded to the Heatsynch protocol with expression of estrus for which ovulations were induced in 8 buffaloes (80%). Mean time interval from the EB injection to ovulation was 50.0${\pm}$2.0 h (range 44.0 to 60.0 h). The interval from the end of LH surge to ovulation was 18.5${\pm}$2.47 h (range 8 to 26 h). The interval from end of estrogen surge to ovulation was 26.75 ${\pm}$2.07 h (range 22 to 36 h). Mean LH peak after EB injection occurred at 20.81${\pm}$1.61 h (range 14 to 28 h) and mean estrogen peak after EB injection occurred at 9.62${\pm}$1.03 h (range 7 to 16 h). Hence, the mean estrogen peak preceded the mean LH peak by 11 h. It was observed that the percentage of conceptions to total number of estruses for control buffaloes was 18 and 30 in summer and winter, respectively, whereas it increased to 26 and 40 in Heatsynch treated buffaloes in respective seasons. The results suggest the possibility of using Heatsynch treatment followed by fixed time A.I. in buffaloes for fertility improvement, especially since the incidence of silent heat in buffaloes is very high.

• 정신신체의학
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• 제29권1호
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• pp.11-16
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• 2021

연구목적 항정신병약물로 인한 QTc간격연장은 심각한 심실성 부정맥을 초래할 가능성 때문에 주의가 필요한 부작용이다. 하지만 현재까지 국내에서 항정신병약물에 의한 QTc간격연장에 대한 연구는 많지 않았다. 본 연구는 조현병 환자에서 QTc간격연장에 영향을 주는 인구학적 및 임상적 변수를 알아보고자 한다. 방 법 일 병원에 입원치료를 받았던 441명 조현병 환자들의 의무기록을 후향적으로 검토하여 QTc간격과 인구학적 및 임상적 변수들을 파악하였다. QTc간격에 영향을 주는 변수를 알아보기 위해 QTc간격을 종속변수로 하여 위계적 중다회귀분석을 수행하였다. 결 과 평균 QTc간격은 417.2±28.4 ms였다. 위계적 중다회귀분석 결과 항정신병약물 단기작용주사제의 사용이 QTc간격연장의 가장 강한 예측인자였다. 결 론 본 연구는 조현병 환자에서 항정신병약물 단기작용주사제 사용이 QTc간격연장에 영향을 줄 수 있으며 조현병 환자의 치료 시 항정신병약물 단기작용주사제 사용에 보다 주의를 기울여야 함을 시사한다.

• 한국연소학회지
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• 제22권1호
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• pp.1-7
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• 2017

This paper presents an experimental study on the effect of double injection strategies on combustion characteristics in a single-cylinder diesel engine. These studies are applied to the double injection strategies, such as $2^{nd}$ injection timing variations with fixed injection interval (8 degree) and variations of injection pressures with fixed injection timing and intervals. The injection quantity was 7 + 7 mg for double injections, and 14 mg for single injection. When the injection pressure was increased, the ignition delay was shortened, and the ISFC (indicated specific fuel consumption) was increased due to the fast termination of combustion by the shortened energizing duration. In addition, the retardation of injection timings toward TDC (top dead center) caused the reduction of ignition delay and the decrease of ISFC with the decrease of FMEP (friction mean effective pressure).

• 한국자동차공학회논문집
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• 제5권3호
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• pp.128-136
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• 1997

Spray characteristics of a fuel injector have an important effect upon engine power and emission. Thus this study was investigated the spray characteristics of the intermittent injection using a gasoline fuel injector. Image processing system and PDA system were utilized for visualization of a spray behavior and measurements of a droplet size and velocity, respectively. Fuel injection duration was fixed with 3ms and injection pressure was varied such as 250kPa, 300kPa, 350kPa. for a high fuel injection pressure, spray tip arrival time was fluctuated at a vigorously disintegrated cross section. Axial velocity was linear correlated with fuel droplet size in the time interval of an injected main spray at spray downstream.

• 대한후두음성언어의학회지
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• 제20권2호
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• pp.136-140
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• 2009

Background and Objectives: Recurrent respiratory papillomatosis (RRP) is difficult to treat because of its tendency to recur and spread throughout the aerodigestive tract. We aimed to estimate the effect of intralesional injections of cidofovir in patients with RRP. Materials and Method: Within the period from January 2003 to July 2007, 13 patients aged 2 to 61 years were treated with intralesional injections of cidofovir combined with surgical excision of RRP. Cidofovir was injected intralesionaly at a concentration of 5 mg/cc after complete removal of the papilloma with $CO_2$ laser or microdebrider. We evaluated the effect of intralesional cidofovir therapy by comparing pre-treatment mean interval of recurrence with post-treatment interval of recurrence. Results: Of 13 patients, two patients showed complete response during follow up period and four patients showed partial response. Seven patients did not respond to cidofovir at all. Mean pre-treatment mean interval of recurrence was 9 months and mean post-treatment interval of recurrence was 13.1 months (p=0.039). There was a statistical significance between the injected dose of cidofovir and post-treatment interval of recurrence (p=0.009). There were no local or systemic side effects caused by cidofovir. Conculsion : Intralesional injection of cidofovir seems to have a potential of a safe and effective adjuvant therapy of RRP. There was a positive correlation between the injected dose of cidofovir and patient clinical outcomes so that administration of higher doses and more frequency of injections should be needed to reduce recurrence. Further study regarding injection therapy regimen for RRP is required.

• 대한간호학회지
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• 제24권3호
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• pp.461-472
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• 1994

The main purpose of this study was to test the validity and reliability of FIPS as an assessment tool for pain in children. The subject were 81 children whose ages ranged from 3 to 14 years old who were experiencing pain from an intramuscular injection. 40 were being seen in a local primary hospital and 41 in a university hospital. The data were collected in two settings at a 6 month interval, the first was on Nov. 5th 1991 in a local clinic by one doctor, the second was on May 1st. 1992 in a university hospital by two nurse. McGrath's(1985) face interval cards and weight box scale which is a numeral scale that contains from one to five boxes of cards were used as measures. To analyze the subject's ability to use the face scale and weight box scale, statistical frequency was employed. To determine the difference in the rated pain in-tensity on the face interval scale and the weight box, Pearson correlation coefficient and t-test were employed. To compare the difference in the rated pain intensity of the face interval scale and the weight box scale according to subject's general characteristics, X²-test was employed. The findings were as follows : 1. The subject's ages were from 3 to 14 with a mean age of 8.3 years old. There were 54(66.7%) male children and 27(33.3%) female children. 2. The number of subjects who correctly displayed cards ranging from none to severe pain was 66(81.5%) and the number who correctly compared two cards 3 times was 73(90.l％). 3. Correlation coefficients between each level card of the FIPS and WBS (Weight Box Scale) were r=.52∼.80 P<0.01. 4. There was no statistical difference in rating of the intensity on the FIPS and WBS.(t=1.12∼l.02, P<0.22∼0.45). 5. The differences in rating pain intensity according to the children's general characteristics were re-lated to age(X²=8.94, P<0.05), but not to sex (X²=0.23, P=0.80).

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.500-510
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• 1996

A Direct injection -mixing total -flow -control sprayer was developed and evaluated . The system provided precise application rates and minimized operator exposure to chemicals as well as providing a possibility for recycling container so f unused chemicals that can causes environmental contamination. Chemicals were metered and injected proportionally to the diluent flow rate to provide constant concentrations. The main diluent flow was varied in response to changes in travel speed. Experimental variables of the sprayer were the control interval, the sensitivity of flow regulating valve, the tolerance of control object and the sensitivity of the injection pump system. The optimal performance of the flow control system was with an average response time of 8.5 sec at an absolute steady state of error of 0.067 L/min (0.8% of flow rate). The average response time of the injection rate was -0.53 sec and the coefficient of variation (CV) of concentration was 3.2%.