• 오토저널
• /
• 제10권4호
• /
• pp.66-74
• /
• 1988

The ignition quality of ignition system is influenced by spark energy, discharge pattern of spark energy and spark duration. In this paper, the characteristics of multiple spark ignition system have been investigated for various number of spark and spark interval. The results, which were compared with those obtained with a standard single spark ignition, show that engine output is increased, and lean misfire limit is extended with the multiple spark ignition system. The most effective number of spark at the most effective spark interval that are determined by engine performance test, were 6 times spark at 0.02ms spark interval. For the above condition of spark, engine torque was increased about 20% comparing with conventional ignition system and lean misfire limit was extended to air-fuel ratio 22.5:1. This study researched the rate of heat release and quantity of heat release influenced by a condition of spark on the mass burned in order to investigate the relationship between the rate of mass burned and number of spark times.

• Journal of Applied and Pure Mathematics
• /
• 제6권3_4호
• /
• pp.105-117
• /
• 2024

In the classical sense, it is known that it is impossible to construct a vector space over the entire set of real numbers with the help of simple interval arithmetic. In this article, it has shown that a vector space can be constructed in the classical sense by helping Markov's extended interval arithmetic on the interval valued Cesaro sequence spaces of non-absolute type. As a result of the positive answers, this idea was extended by us with some theorems. Consequently, a new perspective was gained to the construction of new types of sequence spaces by using different algebraic operations on interval-valued sequence spaces.

• 한국산업정보학회논문지
• /
• 제19권2호
• /
• pp.1-13
• /
• 2014

In IEEE 802.11p/1609-based vehicular networks, vehicles are allowed to exchange safety and control messages only within time periods, called control channel (CCH) interval, which are scheduled periodically. Currently, the length of the CCH interval is set to the fixed value (i.e. 50ms). However, the fixed-length intervals cannot be effective for dynamically changing traffic load. Hence, some protocols have been recently proposed to support variable-length CCH intervals in order to improve channel utilization. In existing protocols, the CCH interval is subdivided into safety and non-safety intervals, and the length of each interval is dynamically adjusted to accommodate the estimated traffic load. However, they do not consider the presence of hidden nodes. Consequently, messages transmitted in each interval are likely to overlap with simultaneous transmissions (i.e. interference) from hidden nodes. Particularly, life-critical safety messages which are exchanged within the safety interval can be unreliably delivered due to such interference, which deteriorates QoS of safety applications such as cooperative collision warning. In this paper, we therefore propose a new interference-aware Dynamic Safety Interval (DSI) protocol. DSI calculates the number of vehicles sharing the channel with the consideration of hidden nodes. The safety interval is derived based on the measured number of vehicles. From simulation study using the ns-2, we verified that DSI outperforms the existing protocols in terms of various metrics such as broadcast delivery ration, collision probability and safety message delay.

• 한국지능시스템학회논문지
• /
• 제16권5호
• /
• pp.550-555
• /
• 2006

구간치 퍼지집합은 Gorzalczang(1983)에 의해 처음 제의되었다. 이를 토대로 Wang과 Li는구간치 퍼지수에 관한 연산으로 일반화하여 연구하였다. 최근에 홍(2002)는 왕과 리의 이론을 리만적분에 의해 구간치 퍼지수 상의 거리측도에 관한 연구를 하였다. 우리는 일반측도와 관련된 리만적분 대신에 퍼지측도와 관련된 쇼케이적분을 이용한 구간치 퍼지수 상의 쇼케이 거리측도를 연구하였다(2005). 본 논문에서는 퍼지수치 퍼지수 상의 쇼케이 거리측도를 정의하고 이와 관련된 성질들을 조사하였다.

• 생물환경조절학회지
• /
• 제1권2호
• /
• pp.169-174
• /
• 1992

간격침적식 수경재배의 실용화 가능성을 검사하고자 10분간격 간격침적식, 15분간격 간격침적식, NFT식 및 분무경system을 이용하여 토마토에 대한 생육비교 실험을 수행하였다. 1. 초장은 NFT식에서 가장 양호하였으나 주근장은 간헐침지식에서 길었으며 수경과 엽수는 처리간에 차이가 없었다. 2. 생체중과 건물중은 생육초기에는 NFT에서 무거웠으나 생육이 진전될수록 간헐침지식에서 더 무거워졌다. 3. 처리 후 43일의 개화수는 분무경 18.5, 15분간격 간헐침지식 17.8, 10분간격 간헐침지식 16.8, NFT 15.1개 순이었으며 과중은 분무경에서 149.1g으로 가장 무거웠다. 4. 식물체당 평균수량은 분무경에서 1929.1g으로 가장 많았고 10분간격 간헐침지식에서 1475.2g으로 다음이었으며, NFT식 및 15분간격 간헐침지식에서 각각 1276.2, 1084.8g으로 가장 적었다. 5. 식물체당 평균수호과수는 분무경 11.0, NFT식 9.7, 15분간격 간헐침지식 8.3, 10분간격 간헐침지식 7.7개 순이었으며 평균과중은 분무경 192.9, 10분간격 간헐침지식 172.4, NFT식 134.0, 15분간격 간헐침지식 126.0 순이었다. 6. 평균과장은 분무경과 10분간격 간헐침지식에서 NFT식과 15분간격 간헐침지식보다 길었으며 평균과폭은 NFT식, 분무경 및 10분간격 간헐침지식에서 비슷한 정도로 15분간격 간헐침지식보다 켰다.

• Journal of Medicine and Life Science
• /
• 제20권3호
• /
• pp.107-114
• /
• 2023

Epidemiological control of coronavirus disease 2019 (COVID-19) is needed to estimate the infection period of confirmed cases and identify potential cases. The present study, targeting confirmed cases for which the time of COVID-19 symptom onset was disclosed, aimed to investigate the relationship between intervals (day) from symptom onset to testing the cycle threshold (CT) values of real-time reverse transcription-polymerase chain reaction. Of the COVID-19 confirmed cases, those for which the date of suspected symptom onset in the epidemiological investigation was specifically disclosed were included in this study. Interval was defined as the number of days from symptom onset (as disclosed by the patient) to specimen collection for testing. A locally weighted regression smoothing (LOWESS) curve was applied, with intervals as explanatory variables and CT values (CTR for RdRp gene and CTE for E gene) as outcome variables. After finding its non-linear relationship, a polynomial regression model was applied to estimate the 95% confidence interval values of CTR and CTE by interval. The application of LOWESS in 331 patients identified a U-shaped curve relationship between the CTR and CTE values according to the number of interval days, and both CTR and CTE satisfied the quadratic model for interval days. Active application of these results to epidemiological investigations would minimize the chance of failing to identify individuals who are in contact with COVID-19 confirmed cases, thereby reducing the potential transmission of the virus to local communities.

• Journal of the Korean Data and Information Science Society
• /
• 제15권4호
• /
• pp.1003-1010
• /
• 2004

Properties of the variable sampling interval(VSI) CUSUM chart for monitoring dispersion matrix of related quality characteristics are investigated. Performances of the proposed charts are evaluated for matched fixed sampling interval(FSI) and VSI charts in terms of average time to signal(ATS) and average number of samples to signal (ANSS). Average number of swiches(ANSW) of the proposed VSI Shewhart and CUSUM charts are also investigated.

• 한국데이터정보과학회:학술대회논문집
• /
• 한국데이터정보과학회 2004년도 춘계학술대회
• /
• pp.151-159
• /
• 2004

Properties of the variable sampling interval(VSI) control charts for monitoring dispersion matrix of related quality characteristics are investigated. Performances of the proposed charts are evaluated for matched fixed sampling interval(FSI) and VSI charts in terms of average time to signal(ATS) and average number of samples to signal (ANSS). Average number of swiches(ANSW) of the proposed VSI charts are also investigated.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2005년도 추계학술대회 학술발표 논문집 제15권 제2호
• /
• pp.121-124
• /
• 2005

퍼지측도와 관련된 폐집합치 쇼케이적분에 대해 장에 의해 연구되어 왔음을 알 수 있다. 본 논문에서는 컴팩트 집합치 함수의 쇼케이적분을 생각하고 이와 관련된 성질들을 조사한다. 특히, 구간치 함수 대신에 컴팩트 집합치 함수를 이용하여 컴팩트 집합치 쇼케이적분의 특성들을 조사한다.

• 운동과학
• /
• 제26권3호
• /
• pp.223-228
• /
• 2017

PURPOSE: This study investigated the protective role of high-intensity interval training against acute liver injury induced by D-galactosamine (D-Gal)/lipopolysaccharide (LPS). METHODS: A total of 30 male BALB/c mice aged 5-week were randomly assigned to high-intensity, interval training group (EX, n=10) or control group in cage (Non-EX, n=20) for 10 weeks. Peritoneal injection of D-Gal (700 mg/kg body weight) and LPS ($10{\mu}g/kg$ body weight) was applied to induce acute liver injury, and liver tissue was harvested 6 hours after the injection. Hematoxylin and Eosin (H&E) staining was used for liver histology. Real-time PCR was used to quantify expression of pro-inflammatory and anti-inflammatory genes in the liver. RESULTS: The liver histology showed that D-Gal/LPS treatment resulted in hepatic damage and increased number of neutrophils in conjunction with upregulation of hepatic IL-6 and $TNF-{\alpha}$ mRNAs and downregulation of hepatic $PPAR{\alpha}$ and SIRT1 mRNAs. On the other hand, the 10-week interval training resulted in a significant improvement in cardiorespiratory fitness assessed as run time to exhaustion on a treadmill. In addition, the interval training attenuated the D-Gal/LPS-induced liver damage and increased number of neutrophil in conjunction with downregulation of hepatic IL-6 and $TNF-{\alpha}$ mRNAs and upregulation of hepatic $PPAR{\alpha}$ and SIRT1 mRNAs. CONCLUSIONS: This study suggests that high-intensity interval training suppresses the D-Gal and LPS-induced acute liver damage and inflammatory responses.