• 한국생산제조학회지
• /
• 제9권6호
• /
• pp.103-110
• /
• 2000

Experimental study of drilling for duralumin A2024 was conducted with intermittently accelerated and decelerated feedrate. It is achieved through a programmed periodic increase and decrease in the feedrate using a machining center. The following experimental results were performed with the objective of solving chip to disposal problems. In conventional drilling of aluminum, long continuous chips are produced with winding around the drill and causing difficulties in eliminating chips from the cutting zone. In order to acquire the basic data necessary to regulate the chip profile, the relationship between cutting variables and chip shape was investigate. The following conclusions are established from the experimental results. At a suitable feed fluctuation ratio, intermittently decelerated feed drilling proved successful in braking chips to appropriate lengths while maintaining stable cutting. Thus, it is an effective method for improving chip disposal. The amplitude of the dynamic component of cutting force in intermittent feed drilling is influenced by the feed fluctuation ratio.

• Journal of Mechanical Science and Technology
• /
• 제16권12호
• /
• pp.1693-1701
• /
• 2002

The intermittent spray characteristics of a multi-hole and a single-hole diesel nozzle were experimentally investigated. The hole number of the multi-hole nozzle was 5, and the hole diameter of the 5-hole and the single-hole nozzle was the same as d$\_$n/=0.32 ㎜ with the constant hole length to diameter ratio(l$\_$n//d$\_$n/=2.81). The droplet diameters of the spray, including the time-resolved droplet diameter, SMD (Sauter mean diameter) and AMD (arithmetic mean diameter) , injected intermittently from the two nozzles into the still ambient were measured by using a 2-D PDPA (phase Doppler particle analyzer). Through the time-resolved evolutions of the droplet diameter, it was found that the structure of the multi-hole and the single-hole nozzle spray consisted of the three main parts : (a) the leading edge affected by surrounding air. and composed of small droplets; (b) the central part surrounded by the leading edge and mixing flow region and scarcely affected by the resistance of air, (c) the trailing edge formed by the passage of the central part. The SMD decreases gradually with the increase in the radial distance, and the constant value is obtained at the outer region of the radial distance (normalized by hole diameter) of 7-8 and 6 for the 5-hole and single-hole nozzle, respectively. The SMD along the centerline of the spray decrease shapely with the increase in the axial distance after showing the maximum value near the nozzle tip. The SMD remains the constant value near the axial distance(normalized by hole diameter) of 150 and 180 for the 5-hole and the single-hole nozzle, respectively.

• 유기물자원화
• /
• 제6권2호
• /
• pp.31-44
• /
• 1998

돈분 슬러리와 톱밥 혼합물을 퇴비화 급속(분해)과정의 파이로트 규모 반응조 성능 평가를 입증하기 위해 간헐통기법으로 퇴비화 처리했다. 계측은 퇴비온도, 산소와 탄산가스농도, 통기량 및 암모니아가스 배출 등의 측정으로 구성됐다. 퇴비화 급속과정의 암모니아 농도는 14일째에 수준이하(I)보다 최적수준(II)부근에서 신속하게 허용범위 34-40ppm 이내로 감소되어 짐을 알 수 있었다. 암모니아가스 저감에 있어서 수분(55-65%), 탄질비(20-40%), 수소이온농도(7-8%) 및 퇴비온도(<$60^{\circ}C$) 등의 최적수준 영향은 상업용 퇴비화에 무시 할 수 없었다.

• Clinical and Experimental Reproductive Medicine
• /
• 제20권2호
• /
• pp.125-130
• /
• 1993

Polycystic ovarian syndrome (PCOS) patients have a characteristic of high leuteinizing hormone (LH) to follicle -stimulating hormone (FSH) ratio. Usually, human menopausal gonadotropin (hMG) is used to induce ovulation in clomiphene citrate-resistant PCOS patients. However, HMG contains two components, namely, LH and FSH, with 50%, respectively. Therefore, FSH is theoretically recommended to stimulate follicular maturation. From the pituitary, LH is secreted by pulsatile pattern. So, we have been using intermittent subcutaneous injection of pure FSH for ovulation induction in 10 PCOS patients from March, 1990 to August, 1992. We obtained good results by intermittent subcutaneous injection of pure FSH. Ovulation is 100% per patient, and 88.2% per cycle. Pregnancy rate is 80% per patient, and 23.5% per cycle. Ovarian hyperstimulation syndrome (OHSS) is 50% per patient, 41.2% per all cycles, and 46.7% per all ovulated cycles. In comparison with HMG, pregnancy rate per cycle is relatively low. But, ovulation rate and pregnacy rate per person is higher than HMG. Because of the strict check of ovaries by the vaginal ultrasonography, OHSS rate is relatively high.

• Archives of Reconstructive Microsurgery
• /
• 제20권1호
• /
• pp.38-42
• /
• 2011

Purpose: To evaluate the effect of intermittent bleeding method in the distal phalanx replantation. Materials and Methods: From January 2007 through June 2009, authors have replanted 117 cases of distal phalangeal amputation in adults at Soo Hospital and Chonbuk National University Hospital. Cases of zone II were 60 cases and zone III 57 according to Allen classification. Male to female ratio was 8.7:1.3. The most common cause was machinery injury in the factory, 98 cases(83.8%), next one was belt injury of the machine, 11 cases(9.4%) and others, 8(6.8%). At least one digital artery and digital nerve were anastomosed under the operating microscope, but vein was impossible to anastomosis as unable to find out in the zone II and III. After anastomosis of one or more digital arteries and nerves, heparine(6,000-10,000 units) was kept to intravenous injection for 24 hours and at the same time fish mouth incision in 2-3 millimeter diameter was made in the distal radial and ulnar margin of the replanted distal phanlanx. From the first 30 minutes to an hour after replantation, incision site was swabbed with heparinized cotton ball for 5 minutes in every 30 to 40 minutes to make sure perfusion for 24 hours, every an hour at the second day, every two hours at the postoperative third to fifth day. Results: 92 cases(78.6%) was completely survived at average postoperative third week follow-up and satisfied with preservation of the finger nail, digit length, good range of motion of the distal interphalangeal joint and acceptable sensibility at average 1.2 years follow-up. Conclusions: Intermittant bleeding method in replantation of crushed distal phalanx impossible to anastomosis of vein at zone II and III of Allen classification was regarded as one of the notable salvage procedure.

• 한국산학기술학회논문지
• /
• 제16권10호
• /
• pp.6766-6778
• /
• 2015

간헐 단식과 주열요법을 병행하여 비만에 관련된 연구를 하는 것이 목적이었다. 두 요법을 35명을 대상으로 11간씩 2회를 실시하였다. 대상자들의 허리둘레, 체중, 체질량지수의 변화, 신체지방비율, 복부내장지방과 기초대사량의 사전 사후의 변화를 연구하였고, 상기 각 항목의 평균 검사치는 요법 실시 전 조사한 C그룹과 1단계 단식(11일 간) 후 조사한 S1그룹 및 2단계 단식(11일 간) 후 조사한 S2그룹과의 감소차이를 조사하였으며, 그 결과는 유의성이 있었고, S1과 S2의 감소차이도 유의성이 있었다. 기초대사량은 S1과 S2의 차이는 유의성이 없었다. 상기의 모든 항목에서 그룹 내 및 간에도 유의성이 있었고, 서로 상관관계가 있었다. 결론적으로 상기 병행 요법이 비만의 수준을 낮추는 효과가 1차 보다는 2차 단식 후에는 더 높았다. 따라서 상기 병행요법이 자연치유의 요법으로 활용의 가치가 있다고 판단한다.

• 한국학교보건학회지
• /
• 제28권3호
• /
• pp.168-176
• /
• 2015

Purpose: The purpose of this study was to investigate the combined influence of the frequency and the intensity of smoking on suicidal ideation and attempts in Korean high school students. Methods: This cross sectional study used secondary data from the 2014 Adolescent Health Behavior Online Survey. A total of 35,094 high school students were included in the study. The study set up two categories for the frequency of smoking - intermittent and daily - and another two for the intensity of smoking - heavy and light. Complex samples logistic regression was used to analyze the combined influence of smoking frequency and intensity on suicidal ideation and attempts. Results: Regardless of frequency and intensity, smoking was more likely to increase suicidal ideation and attempts than non-smoking. Among smokers, intermittent heavy smokers (suicidal ideation: Adjusted Odds Ratio [AOR]: 1.406, 95% Confidence Interval [CI]: 1.015~2.161, p=.012; suicidal attempts: AOR: 2.977, 95% CI: 1.814~4.886, p<.001) or daily heavy smokers (suicidal ideation: AOR: 1.274, 95% CI: 1.017~1.596, p=.035; suicidal attempts: AOR: 1.717, 95% CI: 1.250~2.359, p=.001) had significantly higher odds of suicidal ideation and attempts than intermittent light smokers. Conclusion: Based on the results, smoking prevention and cessation are essential to preventing suicides in adolescents. Especially, smoking intervention programs are needed to reduce smoking intensity in smokers.

• Animal Bioscience
• /
• 제34권7호
• /
• pp.1243-1252
• /
• 2021

Objective: An experiment was conducted to investigate the continuous and intermittent lighting program effects on terms of the productive performance, carcass traits, blood biochemical parameters, innate immune and oxidative status in broiler chicks. Methods: A total of 600 Cobb-500 one day old chicks were randomly allocated into six equal groups (100 chicks per treated group with five replicates of 20 chicks each) based on lighting program; 22 continuous lighting (22 C), 11 h lighting+1 darkness twice daily (11 L/1 D), 20 h continuous lighting (20 C), 5 h lighting+1 darkness four times daily (5 L/1 D), 18 h continuous lighting (18 C) and the final group subjected for 3 h lighting+1 h darkness six times daily (3 L/1 D). The experimental period lasted 42 days. Results: Compared with those under the intermittent light program, broiler chicks exposed to continuous lighting for 22 h had significant improvement in live body weight and carcass (dressing and breast percentage) measured traits. Though reducing lighting hours significantly reduced feed intake and feed conversion ratio values. Different lighting programs revealed no significant effect on all blood biochemical parameters. Oxidative stress and innate immunity parameters significantly enhance by reducing lighting hours (3L/1D). Conclusion: The findings suggest that reducing lighting hours up to 3L/1D would be more useful in enhancing feed efficiency, innate immunity, and oxidative status compared with continuous lighting programs on broilers.

• Agricultural and Biosystems Engineering
• /
• 제7권1호
• /
• pp.42-47
• /
• 2006

The objective of this study was to investigate the effects of air-phase germination with water-spraying and anion stimuli on germination ratio, sprout growth and ${\gamma}$-aminobutyric acid (GABA) of brown rice. Air-phase germination method with intermittent spraying water improved germination ratio and sprout growth by about 100% compared with the conventional water-soaking method. Anion radiation was applied during the germination process and improved the germination ratio, sprout growth and color quality of the germinated brown rice. Germination ratio and sprout growth were improved up to 9% with anion radiation, and its brightness was higher than brown rice germinated with no anion radiation. The air-phase germination with water-spraying improved the GABA content of germinated brown rice by about 8-9 times compared with that of brown rice.

• 한국생산제조학회지
• /
• 제24권2호
• /
• pp.203-210
• /
• 2015

This paper investigates the failure of a car with a 2.5-liter CRDi engine of the Hyundai Company. The failure is caused by intermittent poor acceleration while driving. To analyze the cause, we investigated the air intake volume, the fuel injection, and the air-fuel ratio, which were determined to be normal. The brake switch signal error was discovered while analyzing the function that limits the output of the engine. While investigating the cause, we discovered the corrosion of the pins on the connector of the brake switch. We determined that it was generated by soapy water flowing in the solar film. Therefore, the cause of the failure was the brake switch signal errors. Additionally, we determined that ECM was the normal fail-safe mode that implemented the override device for safety during normal acceleration. Based on these results, further solar film experiments must be conducted to fully elucidate the causes.