• Title/Summary/Keyword: limit index

Search Result 595, Processing Time 0.028 seconds

Determination of Process Capability Index considering Inspection Precision (검사정밀도를 고려한 공정능력지수의 결정)

  • 송서일;조영찬
    • Journal of Korean Society for Quality Management
    • /
    • v.27 no.4
    • /
    • pp.114-122
    • /
    • 1999
  • As the rapid growth of Industrial society, many enterprises are inclined to ppm management from the traditional$3\'{o}$ management method. Therefore it is need to extend process capability index for guarantee of quality assurance level to ppm unit. Thus, in this paper, using the probability of standard normal distribution from $ 3\'{o}; to; 6\'{o}$ which was developed by Song(1997), the capability index which is proposed considers the numbers of inspection facility and quality assurance level. Also, quality assurance level is determined by considering the precision of inspection when one and two sided specification limits are given for the probability which is out of the specification limit.

  • PDF

A Study on the Injury Criteria of the Occupant Protection Performance of Crush Cushions (충격흡수시설의 탑승자보호 성능평가 기준에 관한 연구)

  • Lim, Jae-Moon;Jung, Geun-Seup
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.16 no.2
    • /
    • pp.49-57
    • /
    • 2008
  • The performance of crash cushion systems is certified through the full scale crash tests by the standard for installation and maintenance guidelines for roadside safety appurtenance. The impact severities of impacting vehicles in collision with crash cushion systems are rated by indices THIV and PHD. Crash test results are considered to study the performance of three crash cushion systems. In case of the frontal impact or the offset frontal impact, the results show that THIV values of three systems are very close to the threshold limit for the occupant protection. Also, the results show that PHD would be improper for the occupant protection performance index. In order to improve the occupant protection performance of crash cushions, ASI needs to be included in the impact severity index.

New Sludge Settling Characteristic Index Considering Sludge Settling Velocity (슬러지침전속도를 고려한 새로운 슬러지침전특성지표의 설정에 관한 연구)

  • Park, Suk Gyun;Kang, Seon-Hong;Kim, Dong-Ha
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.20 no.3
    • /
    • pp.451-460
    • /
    • 2006
  • While sludge settles down in a batch column, sludge concentration becomes high. Sludge concentration change is one of the most critical causes of the sludge settling velocity variation. Therefore, sludge concentration change causes sludge index to change. SVI is more sensitive than other sludge indexes to the change of sludge concentration. And if sludge-water interface has reached final height within 30minutes, SVI is not suitable for prediction of sludge settling characteristic, Therefore, SVIs of each sludge are, in some cases, different although each sludge has the same settling velocity. But SVI has been widely used to interpret sludge settling characteristic by a simple testing method. This work has two purposes. The first purpose is to predict sludge settling velocity by using sludge-water interface settling velocity. And the second purpose is to develop new sludge settling characteristic index to exactly interpret sludge settling characteristic by overcoming the limit of SVI.

Correlation Analysis of Soil Parameters of Dredged and Reclaimed Marine Clay in Gyeonggi Coast (경기해안 준설매립 해성점토의 토질정수 상관성 분석)

  • An, Soo-Yeong;Yoo, Nam-Jae
    • Journal of Industrial Technology
    • /
    • v.35
    • /
    • pp.81-88
    • /
    • 2015
  • The single regression method was used to analyze the correlationship between the compression index with mechanical properties for reclaimed marine clays in the Gyeonggi coast of Korea. As results of performing regression analysis for 62 samples about reclaimed marine clays in the Gyeonggi coast of Korea, linear regression lines between compression index and natural water content, void ratio in situ, and liquid limit respectively were obtained. The changed properties of reclaimed soil due to disturbance during dredging and reclaiming could be investigated by comparing with the existing empirical correlation equations for the original ground where dredging was performed.

  • PDF

Equivalent 10-Hz Flicker Index Calculation Using Half-cycle Sliding Window and Recursive RMS Method (반주기 슬라이딩 윈도우와 재귀적 실효치 계산을 이용한 국내 플리커 평가지수 산출기법)

  • Cho, Soo-Hwan
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.60 no.11
    • /
    • pp.2017-2020
    • /
    • 2011
  • Flicker, which is also known as voltage fluctuation, is an electromagnetic phenomenon generated by large scale nonlinear loads, such as arc furnaces and welding machines. Since a severe and continuous flicker can cause to some damages to electrically sensitive loads as well as human's visual irritations, it needs to be appropriately managed by being accurately measured, quantified and assessed. In Korea, an equivalent 10-Hz flicker index, shortly ${\Delta}V10$, is used to determine the permission limit of flicker. This paper presents an efficient calculation of the flicker index by using a half-cycle sliding window and a recursive method, showing a concrete calculating procedure of ${\Delta}V10$ from the viewpoint of signal processing.

Response of the Geomagnetic Activity Indices to the Solar Wind Parameters

  • Ahn, Byung-Ho;Park, Yoon-Kyung
    • Journal of Astronomy and Space Sciences
    • /
    • v.25 no.2
    • /
    • pp.129-138
    • /
    • 2008
  • This study attempts to show how the geomagnetic indices, AU, AL and Dst, respond to the interplanetary parameters, more specifically, the solar wind electric field VBz during southward interplanetary magnetic field (IMF) period. The AU index does not seem to respond linearly to the variation of southward IMF. Only a noticeable correlation between the AU and VBz is shown during summer, when the ionospheric conductivity associated with the solar EUV radiation is high. It is highly likely that the effect of electric field on the eastward electrojet intensification is only noticeable whenever the ionospheric conductivity is significantly enhanced during summer. Thus, one should be very cautious in employing the AU as a convection index during other seasons. The AL index shows a significantly high correlation with VBz regardless of season. Considering that the auroral electrojet is the combined result of electric field and ionospheric conductivity, the intensification of these two quantities seems to occur concurrently during southward IMF period. This suggests that the AL index behaves more like a convection index rather than a substorm index as far as hourly mean AL index is concerned. Contrary to the AU index, the AL index does not register the maximum value during summer for a given level of VBz. It has something to do with the findings that discrete auroras are suppressed in sunlight hemisphere (Newell et al. 1996), thus reducing the ionospheric conductivity during summer. As expected, the Dst index tends to become more negative as VBz gets intensified. However, the Dst index (nT) is less than or equal to 15VBz(mV/m) + 50(Bz < 0). It indicates that VBz determines the lower limit of the storm size, while another factor(s), possibly substorm, seems to get further involved in intensifying storms. Although it has not been examined in this study, the duration of southward IMF would also be a factor to be considered in determining the size of a storm.

A Study on the Calculation of Consolidation Constants using Moisture Content of Sedimentary Clay in Busan and Gyeongnam Regions (부산·경남지역 퇴적 점토의 함수비를 이용한 압밀정수 산정 연구)

  • Sung-Uk Kang;Dae-Hwan Kim;Tae-hyung Kim;Chin-Gyo Chung;In-Gon Joo
    • Journal of the Korean Geosynthetics Society
    • /
    • v.23 no.1
    • /
    • pp.39-47
    • /
    • 2024
  • In this study, physical property tests and standard consolidation tests were conducted on the marine clay of Busan New Port and North Port, the middle and lower reaches of the Nakdong River including Gimhae and Yangsan, and Ulsan regions. The moisture content, a property unrelated to sample disturbance with small individual test errors, was used for regression analysis with the compression index, virgin compression index, consolidation coefficient, expansion index, and secondary compression index, among others. Subsequently, the correlation and accuracy were evaluated. Upon analyzing the correlation between the moisture content, void ratio, and liquid limit commonly used physical properties for calculating compression indexes, it was confirmed that the liquid limit had the lowest correlation. Through a linear regression analysis of the consolidation constants using the current moisture content in the natural state, a high correlation was demonstrated. Relationship equations were then presented to determine settlement and settlement time. This study suggests that moisture content can be utilized as an alternative for evaluating and calculating consolidation constants when examining ground settlement in sedimentary clays distributed in the Busan and Gyeongnam regions.

Evaluation of Nutritional Deficit Status in Hemodialysis Patients' Based on Usual Dietary Intake, Anthropometric and Biochemical Parameters (일상식이섭취상태와 신체계측 및 혈액화학적 영양지표에 의한 혈액투석 환자의 영양결핍상태 평가)

  • Sohng Kyeong-Yae
    • Journal of Korean Academy of Fundamentals of Nursing
    • /
    • v.3 no.1
    • /
    • pp.68-80
    • /
    • 1996
  • Long-term hemodialysis(HD) patients manifest various signs of protein and caloric malutrition due to poor intake of nutrients and other causes. Poor nutritional status increases the mortality and morbidity rates in HD patients. Thus, mataintnance of adequate nutritional status has been a major task in taking care of patients receiving HD. This study was to evaluate the nutritional status of HD patients and to clarify the degree of nutritional deficit based on usual dietary intake, anthropometric and biochemical indicators. Sixty HD patients comprised a HD group, while the control group consisted of 60 healthy adults whose age and sex matched those of the HD group. Nutritional status was evaluated by dietrary intake using instant nutritional scale, anthropometric measures, serum protein concentrations and the number of lymphocytes. The data were analyzed by using Chi-square test and unpaired t-test. The results are as follows. 1. Regarding usual dietary intake of HD group. 1) Estimated caloric intake was significantly lower than the recommended daily allowance(RDA) and among them, 35% were taking calories less than 85% of the RDA. 2) Estimated protein intake was significantly higher than the RDA and among them 40% were taking protein more than 115% of the RDA. 3) Estimated fat intake was lower than the RDA. 4) Vitamin A, B, $B_1,\;B_2$, C and niacin in take was lower than the RDA respectively. 5) Estimated ferrous intake was within the normal limit the RDA while estimated calcium intake was higher than the RDA. 6) Both calorie and protein intake were higher for the 10 patients who had been under continuous ambulatory peritoneal dialysis than for the patients under HD from the beginning. 2. Regarding anthropometric measures : 1) Body mass index(BMI), midarm circumference(MAC), and triceps skinfold thickness(TSF) were lower in the HD group than in the control group. 2) Among HD group, 47.1% were within the normal limit of BMI, while 86.7% were within the same limit in the control group. 3) Among HD group, 35.0% were within the normal limit of MAC, while 83.3% were within the same limit in the control group. 4) Among HD group, only 8.3% were normal, 30.3% were mild deficit status of TSF, while 50% were normal and 48.3% were mild deficit status in the control group. 3. Regarding biochemical laboratory tests 1) Albumin, transferrin concentrations and the number of lymphocytes were lower in HD group than in the control group. 2) Among HD group, 98.3% were within the normal limit of albumin concentration and all were within the same limit in the control group. 3) Among HD group, only 11.7% were within the normal limit of transferrin concentration, while 81.7% were within the same limit in the control group. 4) Among HD group, 25% were within the normal limit, while 93.3% were within the same limit in the control group. The above findings suggest that HD patients were in nutritional deficit status. Adequate diet therapy and periodical evaluation of the nutritional status in HD patients are needed. Accordingly, it turned out that anthropometric measures were very reliable parameters and easy to use to evaluate nutritional status. So nurses are encouraged to adopt anthropometric measures to examine nutritional deficit status of HD patients.

  • PDF

An Index Method for Storing and Extracting XML Documents (XML 문서의 저장과 추출을 위한 색인 기법)

  • Kim Woosaeng;Song Jungsuk
    • Journal of Korea Multimedia Society
    • /
    • v.8 no.2
    • /
    • pp.154-163
    • /
    • 2005
  • Because most researches that were studied so far on XML documents used an absolute coordinate system in most of the index techniques, the update operation makes a large burden. To express the structural relations between elements, attributes and text, we need to reconstruct the structure of the coordinates. As the reconstruction process proceeds through out the entire XML document in a cascade manner, which is not limited to the current changing node, a serious performance problem may be caused by the frequent update operations. In this paper, we propose an index technique based on extensible index that does not cause serious performance degradations. It can limit the number of node to participate in reconstruction process and improve lots of performance capacities on the whole. And extensible index performs the containment relationship query by the simple expression using SQL statement.

  • PDF

Behavioral responses and tolerance limits of wild goldeye rockfish Sebastes thompsoni to high temperature exposure (고 수온 노출에 따른 자연산 불볼락 Sebastes thompsoni의 행동반응 및 내성 한계)

  • Sung-Jin Yoon;Jin-Hyeok Park
    • Korean Journal of Environmental Biology
    • /
    • v.40 no.3
    • /
    • pp.247-254
    • /
    • 2022
  • To investigate the tolerance limit and critical thermal maximum (CTM), behavioral responses of wild goldeye rockfish Sebastes thompsoni according to exposure to high water temperature were observed using a continuous behavior tracking system. As a result, behavioral index (BI) of S. thompsoni in each temperature (20.0, 25.0, and 30.0℃) showed a significant difference (p<0.05) when compared with the value measured in a stable condition of 15.0℃. The activity level of S. thompsoni exposed to 25.0℃ decreased sharply after 20 hours. Their rest time at the bottom of experiment chamber increased, and their normal swimming and metabolic activities were disturbed. In addition, at a high water temperature of 30.0℃, S. thompsoni reached the limit of resistance and showed a sub-lethal reaction of swimming behavior, with energy consumption in the body increased and all test organisms died. In conclusion, the eco-physiological response of S. thompsoni to water temperature varied greatly depending on the fluctuation range of the exposed temperature and the exposure time. In addition, the tolerance limit of S. thompsoni to high water temperature was predicted to be 25.0-30.0℃. The maximum critical thermal that had a great influence on the survival of this species was found to be around 30.0℃.