• 대한기계학회논문집B
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• 제39권9호
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• pp.727-734
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• 2015

세계적으로 유가 상승에 따른 내연기관의 에너지 변환 효율을 높이고자 하는 연구가 활발히 진행되고 있다. 가솔린엔진에서 높은 열효율을 실현하기 위해서는 희박연소에 의한 비열비의 증가 및 단열화염온도의 저감에 의한 열효율 향상이 필수적이다. 직접분사식 가솔린 엔진은 연료를 직접 연소실에 공급하고 정밀한 연소제어를 통해 희박 연소가 가능하게 하지만 희박연소 한계의 확대와 안정된 희박연소제어가 요구된다. 희박연소 엔진에 대한 삼원촉매의 배출가스 저감특성은 높은 공기과잉률 및 낮은 배기가스 온도로 인해 매우 제한적이다. 이에 효과적인 삼원촉매의 개발을 위해 승용 차량용 엔진의 주요 연비시험 운전조건인 2000 rpm BMEP 2bar 조건에서 공기과잉률의 변화에 따른 배출가스 반응 및 생성 특성을 비교하였다. 희박연소 조건에서 $NO_2$가 생성되었으며, $NO_2$의 비율은 공기과잉률이 증가할수록 증가하고 $N_2O$는 감소하였다.

• 분석과학
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• 제25권6호
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• pp.382-387
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• 2012

산화에틸렌($C_2H_4O$, Ethylene oxide, EtO)은 에탄올아민 같은 공업적으로 중요한 물질이나 에틸렌 글리콜의 생산 원료 또는 살균제로 이용되는 물질이다. 산화에틸렌은 불화탄화수소를 분사제 또는 바탕가스로 하여 액화혼합가스로 제조되어 열에 약한 의료기기나 저장시설의 소독에 널리 사용되고 있다. 액화혼합가스의 생산 및 사용 시 품질관리 및 안전관리를 위해 각 성분의 몰분율을 정확히 측정할 필요가 있다. 휘발성 액체시료 중 각 기체성분들은 증기압이나 끓는점 등과 같이 물리 화학적 성질이 다르므로 몰분율 측정 시 실린더 내부의 상층에 평형을 이루고 있는 기체시료 또는 하층의 기화되지 않은 액체시료를 직접 측정기기에 주입하는 방법에 따라 측정 결과가 다를 수 있다. 본 연구에서는 액화혼합가스를 액체 또는 기체 상태로 주입할 수 있는 새로운 온라인 시료도입장치를 고안하고 GC/AED (gas chromatograph-atomic emission detector)를 사용하여 산화에틸렌과 불화탄화수소 액화혼합가스를 측정하였으며 AED의 검출특성, 기기에 주입 시 시료의 상태, 측정파장에 따른 측정결과의 정확성 및 반복성을 조사하였다.

• 대한한방내과학회지
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• 제11권2호
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• pp.22-42
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• 1990

Sabaiksan has been prescribed to treat various allergic diseases in herbal medicine which were induced by various vasoactive amine released from the mast cells. The constituents of Sabaiksan are Mori Cortex Radices(MCR), Lycii Cortex Radicis(LCR) and Glycyrrhizae Radix(GR). Recently, simple models of compound 48/80 induced anaphylactic shock and cutaneous reaction in vivo were developed to test various agents employed in the field of allergy and toxicology research. The purpose of this study is to evaluate the effects of Sabaiksan on compound 48/80 induced anaphylactic stock, cutaneous reaction and mesenteric mast cell degranulation rate in ICR mice, and on compound 48/80 induced peritoneal mast cell degranulation and histamine release in vitro. Groups of ICR mice were intraperitoneally pretreated with $100{\mu}{\ell}$ of saline, $MCR(2g/m{\ell}),\;LCR(2g/m{\ell}),\;GR(g/m{\ell})$ or Sabaiksan itself(MCR+LCR+GR) at 24, 12 and 1 hour before compound 48/80 solution ($10{\mu}{\ell}/gm$ B. W) were peritoneally given into them, and then mortality within 72 hours after the compound 48/80 injection, and mesenteric mast cell degranulation rate at 15 minutes after compound 48/80 injection were calculated. In vitro experiment, $400{\mu}{\ell}$ of rat peritoneal mast cell suspension$(10^6cell/m{\ell})$ were pretreated with $50{\mu}{\ell}$ of saline, $MCR(2g/m{\ell}),\;LCR(2g/m{\ell}),\;GR(g/m{\ell})$ or Sabaiksan itself at room temperature for 30 minutes, and then $50{\mu}{\ell}$ of compound 48/80 solution $(100{\mu}g/m{\ell})$ were added into it. 30 minutes after the addition of compound 48/80 solution, histamine release assay in the supernatant of peritoneal mast cell suspension were performed employing radioisotope enzymatic assay and morphologic changes of mast cells in each regular time point were photographed. Compared with controls, compound 48/80 induced anaphylactic shock was significantly inhibited by MCR and GR pretreatment into the ICR mice. Significant inhibition of compound 48/80 induced cutaneous reaction, mesenteric mast cell degranulation rate in vivo and histamine release from the rat peritoneal mast cells in vitro was observed only in MCR pretreated group. From the above results, it is suggested that MCR component of Sabaiksan may playa key role to suppress mast cell function since it has been applied to various allergic diseases.

• Journal of Biosystems Engineering
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• 제6권2호
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• pp.1-8
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• 1982

The objective of this study was to find out the technical feasibility of ethanol-diesel fuel blends as a diesel engine fuel. Fuel properties essential to the proper operation of a diesel engine were determined for blends containing several concentrations of ethanol in No. 2 diesel fuel. A single-cylinder diesel engine for a power tiller was used for the engine tests, in which load, speed and fuel consumption rate were measured. The fuels used in tests were No. 2 diesel fuel and a blend containing 10-percent ethanol and 90-percent No. 2 diesel fuel. The results of the study are summarized as follows. 1. It was not possible to blend ethanol and No. 2 diesel fuel as a homogeneous solution even though anhydrous ethanol was used. The problem of blending ethanol in No. 2 diesel fuel could be solved by adding butanol about 5% of the amount of ethanol in the blends. 2. Because ethanol had a much lower boiling point ($78.3^{\circ}C$ under atmospheric pressure) than a diesel fuel, it was necessary to store ethanol-diesel fuel blends airtight in order to prevent them from evaporation losses of ethanol. 3. The addition of ethanol to No. 2 diesel fuel lowered the fuel viscosity and the cetane rating, but a blend of 10% ethanol and 90% diesel fuel had a viscosity and a cetane rating well above the KS minimum values for No. 2 diesel fuel. 4. At the rated speed, the specific fuel consumption of No.2 diesel fuel was lower than that of the 10% ethanol blend for the almost entire range of load. However, under the overload condition the specific fuel consumption was lower for the 10% ethanol blend. 5. Under the variable-speed full-load tests, both fuels produced approximately the same torque and power. At the speeds of 1600rpm or below, the specific fuel consumption of No. 2 diesel fuel was lower than that of the 10% ethanol blend. At the speeds of 1600rpm or above, however, the specific fuel consumption was lower for the 10% ethanol blend. 6. At the ambient temperature above $15^{\circ}C$, the use of the 10% ethanol blend in the engine created a vapor lock in the fuel injection pump and stalled the engine. The vapor locking problem was overcome by chilling the surroundings of the fuel injection pump and the cylinder head with water.

• Journal of Dental Anesthesia and Pain Medicine
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• 제20권4호
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• pp.203-212
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• 2020

Background: This research evaluated the numbness produced by lignocaine at an equal or higher concentration than that of 4% articaine through a single point of injection for maxillary third molar surgery. This randomized double-blind study was conducted to compare the anesthetic efficiency of 4% lignocaine with that of 4% articaine in impacted maxillary third molar surgery using a single buccal infiltration alone. Methods: The study participants were 30 healthy patients requiring the bilateral surgical removal of symmetrically-positioned maxillary third molars. Using a split-mouth design, each patient randomly received buccal infiltration of 1.7 ml of 4% lignocaine and 1.7 ml of 4% articaine during two separate appointments. After 15 minutes of anesthetic injection, surgery was performed by the same surgeon using a consistent technique on both sides. Pinprick test pain scores of the buccal and palatal gingiva of the maxillary third molar after 10 minutes and 15 minutes latencies, pain scores during the surgery, the need for supplemental anesthesia, and patients' satisfaction with anesthetic efficiency were recorded. Surgery performed without supplemental anesthesia was categorized as successful. Results: The success rates of 4% lignocaine and 4% articaine (83.34% vs. 86.67%, P = 1.00) were not significantly different. Only 5 cases (4 cases in the articaine group and 1 case in the lignocaine group) reported mild pain and pressure sensation (NRS ≤ 1) on probing at the palatal side after 15 minutes of latency (P = 0.25). The pain scores of maxillary third molar surgery in the two groups were not significantly different (P > 0.05). Moreover, the statistical analysis confirmed the comparable patient satisfaction of two study groups (P = 0.284). Conclusion: This study provides evidence that single buccal infiltrations of 4% lignocaine and 4% articaine have comparable anesthetic efficacy and success rates for impacted maxillary third molar surgery. Both 4% lignocaine and 4% articaine can produce effective palatal anesthesia and pain control using buccal infiltration alone after 15 minutes of latency.

• Journal of Acupuncture Research
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• 제24권4호
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• pp.143-155
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• 2007

Objectives: To observe the effect of acupuncture and nerve block combination treatment on adhesive capsulitis patients. Methods : 59 voluntary patients were randomly assigned to acupuncture treatment group(E group, n=22), nerve block treatment group(W group, n=17) and acupuncture and nerve block combination treatment group(EW group, n=20). The E group received acupuncture treatment on LI15, $TE_{14}$, $GB_{21}$ and Master Dong's acupuncture points, Shin-gwan and Gyun-joong, twice a week for 4 weeks. The W group received suprascapular nerve block, subacromial injection and trigger point injection, twice a week for 4 weeks. The EW group received the same treatment as the W group and after 5minutes of rest, successively received the treatment identical to that of E group. All three groups were instructed to practice groups were instructed to practice self exercise during their daily lives. Evaluations were made before treatment and after 1, 2, 3 and 4week treatment. Constant Shoulder Assessment(CSA), Shoulder Pain and Disability Index(SPADI), Range of Motion(ROM), the patient's treatment satisfaction measured by Visual Analogue Scale(VAS) and Digital Infrared Thermographic Imaging(DITI) were used as assessment tools. The obtained data were analyzed and compared. Results : The E group showed significant improvement(p<0.05) on CSA, SPADI, VAS and DITI. As for ROM, Adduction and Extension improved significantly(p<0.05). The W group showed significant improvement(p<0.05) on CSA, SPADI, VAS and DITI. As for ROM, Abduction and Extension improved significantly. The EW group showed significant improvement(p<0.05) on CSA, SPADI and VAS. As for ROM, Adduction, Abduction, Extension and Flexion improved significantly. The improvement of CSA, VAS and Abduction ROM in the EW group was significantly(p<0.05) superior compared to the groups treated with single type of treatment. Conclusion : It is suggested that acupuncture and nerve block combination treatment for adhesive capsulitis patients is more effective than the two single treatments. Through further studies, the acupuncture and nerve block combination treatment model may be developed into East-West Collaboration Model in treating adhesive capsulitis.

• 기본간호학회지
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• 제4권2호
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• pp.319-336
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• 1997

This study was done to identify the reality in doing the intradermal skin test of injectional antibiotics and to serve a basis to the clinical and educational situations. For the study, the survey was done to the staff nurses who are working at one of the selected 39 hospitals in the capital area, from January 6 to Feburary 8 in 1997. The data analysis was done by mean, standard deviation, Fisher's exact test, t-test, ANOVA through running SAS computer program. The results of the study were as follows : 1. The dilution ratio of the antibiotics was mostly 1 : 10 regardless of what kind of antibitics. Making the contrast was done only for the suspended to the antibiotics. Mostly the reaction was detected after 15 to 20 minutes from its diameter of redness and wheals. Most of the respondents answered they do the intradermal skin test only once for the same antibiotics. 2. In the education on the skin test the 66.7% from the respondents had exposed to the education mostly through the new nurses orientation. The 85,4% from them answered the need of the continuous education which had a significant difference in the number of beds(p=.046). The had experiences of detecting positive reactions(98.3%), and of anaphylaxis(49.5%) which had a significant difference in experience(p=.002) and in their age groups(p=.000). 3. The averge score of the confidence on the intradermal skin test was 3.32 form 4-point scale. Also it had a significant difference from the number of beds(p=.010), the year of experiences(p=.016), and their age groups(p=.046). 4. From the general characteristics of respondents, the injection methods had a significant difference in the amounts of injection, whether adopting the contrast pairing, and the repeatable skin tests for the same antibiotics. 5. Only 15 from 39 hospitals had their protocol about the intradermal skin test provided by nursing department which differs in its contents from that provided by the medical information center. From the results of the study, it is suggested that the continuous education on the intradermal skin test and its unified protocol should be provided. Also it is recomended that the drug manufacturer should notice about its anaphylactic cautions and pack its extra skin test use.

• 대한방사선기술학회지:방사선기술과학
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• 제33권3호
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• pp.185-192
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• 2010

거대핵세포(megakaryocyte)에서 유래된 혈소판은 백혈구와 더불어 방사선에 민감하여 가장 먼저 감소하므로 방사선장해의 지표로 활용된다. 따라서 혈소판이 부족하게 되면 점상출혈(dot hemorrhage)이 계속되고 혈구 수의 감소와 면역기능 저하로 이어진다. 특히, 전신조사(whole body irradiation)로 4~6 Gy를 받을 경우, 3주 후 혈소판이 최하로 감소되어 출혈과 빈혈에 의한 조혈기계 장해의 사망원인이 된다. 따라서 본 연구는 혈소판 장해의 메카니즘을 밝히고 방어효과를 알아보고자 하였다. 실험에 사용한 방어물질은 마늘 성분의 알리인(Alliin)을 사용하였으며, rat의 꼬리 정맥에 투여한 후 전자현미경(TEM)으로 관찰하였다. 연구 결과, 5 Gy 방사선조사(Irradiation) 후 10일 경과된 혈소판 조직에서는 세포막이 심하게 손상되어 풍선모양으로 부풀어 올랐으며, 당질층(glycocalyx)이 비후되었다. 조사 후 20일 경과된 혈소판에서는 소기관들의 형태를 알아볼 수 없을 정도로 손상되었으며, 세포질의 내용물이 간질부위로 유출되어 손상이 매우 심하였다. 또한 과립들의 형태도 관찰되지 않았다. 30일 경과된 혈소판에서는 가운데 부분에서 공포(vacuole)가 생기고 조직의 손상이 관찰되었다. 하지만 Alliin을 정맥 투여한 실험군에서는 과립(granules)들의 형태가 대조군과 같이 일정하게 유지되고 있었으며, 세포막의 손상도 확인되지 않았다. 따라서 Alliin의 혈관투여시 혈소판의 방사선방어 효과를 확인할 수 있었다.

• Korean Journal of Acupuncture
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• 제22권2호
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• pp.57-74
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• 2005

Objective : Frutus gardeniae, seed of Gardenia jasminoides Ellis is one of the crude drugs used for the treatment of inflammatory condition in oriental medicine. Methodes : The present study aimed to examine the analgesic effect and anti-inflammatory effect of Frutus gardeniae extract (FGE) on a rat model of ankle sprain pain, and the relations between FGE-induced effect and endogenous nitric oxide (NO) and inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and c-Fos protein expression in the spinal cord. As a chronic pain model, ankle sprain pain model was used to test the effect of FCE injection applied to acupuncture point. After the induction of ankle sprain, rats subsequently showed a reduced stepping force of the affected limb for at least the next 4 days. The reduced stepping force of the limb was presumably due to a painful knee. FGE dissolved in normal saline was injected several acupoints. Results : After the treatment, behavioral tests measuring stepping force were periodically conducted during the next 8 hours. FGE produced significant improvement of stepping force of the hindlimb affected by the ankle sprain lasting at least 4 hours. FGE produced the improvement of stepping force of the affected hindlimb in a dose-dependent manner. In addition, FGE injection showed inhibitory effect on the paw edema induced by ankle sprain. Both NO production and iNOS, COX-2 protein expression increased by ankle sprain were suppressed by FGE. FGE on combination with electroacupuncture (EA) produced more powerful and longer lasting improvement of stepping force of the hindlimb affected by the ankle sprain than either FGE or EA did. The present study suggest that FGE produces a potent analgesic effect on the ankle sprain pain model of the rat and that FGE-induced analgesia modulate endogenous NO through the suppression of iNOS/COX-2 protein expression.

• Journal of Acupuncture Research
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• 제23권5호
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• pp.177-185
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• 2006

Objectives : To observe the effect of acupuncture treatment and western medical treatment on frozen shoulder patients. Methods : 39 voluntary patients were randomly assigned to the Eastern treatment group(E group, n=22) and the Western treatment group(W group, n=17). The E group received acupuncture treatment on LI15, TE14, GB21 and Master Dong's acupuncture points, Shin-gwan and Gyun-joong, twice a week for 4 weeks. The W group received suprascapular nerve block, subacromial injection and trigger point injection, twice a week for 4 weeks. Both groups were instructed to practice self exercise during their daily lives. Evaluations were made before treatment and after treatment using Constant Shoulder Assessment(CSA), Shoulder Pain and Disability Index(SPADI) and the patient's satisfaction concerning the treatment was measured by Visual Analogue Scale(VAS). The obtained data were analyzed and compared. Results : The E group showed significant improvement(p<0.05) according to the CSA and SPADI. The patient's satisfaction scored 5.67 on a scale of 10. The W group showed significant improvement(p<0.05) according to the CSA and SPADI. The patient's satisfaction scored 7.73. But the difference between the two groups were insignificant according to CSA and SPADI. Conclusion : Both acupuncture and nerve block treatment significantly improved frozen shoulder. But the difference of the two treatments was insignificant.