• Title/Summary/Keyword: density index

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A Study on the Estimation Method of Automative Ride Comfort (자동차 승차감 평가 방법에 관한 연구)

  • 황성연
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1997.10a
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    • pp.108-113
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    • 1997
  • In these days, customers require high-quality, high-performance, high-ride comfort for Automobile and then the automotive manufacturers concentrated on study of electrical, high-performance, low-cost of parts and sub-parts. In this paper, for ride comfort estimation PSD(Power Spectral Density) of acceleration at eight test point are measured, and then are calculated with new index of ride comfort. The new index of ride comfort developed for optimal design, real test, applied the actual. It can apply for various fields.

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Response Time Index and Suppression Capability of Standard and Quick Response Sprinkler Head (표준형 및 속동형 스프링클러헤드의 반응시간지수와 소화성능)

  • 정길순;이병곤
    • Journal of the Korean Society of Safety
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    • v.13 no.4
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    • pp.59-70
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    • 1998
  • In this study, response time index(RTI) of standard and quick response type sprinkler head are measured and compared through ramp and plunge test in heated wind tunnel. Also discharge rate and water distribution, actual delivered density(ADD), fire test with wood cribs are performed to compare the fire suppression capability and the operation time and temperature between standard and quick response type sprinkler head.

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Flammability of insulators for railroad vehicles (차량용 단열재의 종류에 따른 난연성 평가)

  • Lee Duck-Hee;Lee Cheul-Kyu;Jung Woo-Sung;Kim Sun-Ok;Back Min
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.477-482
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    • 2004
  • New materials are being considered for insulator of railroad vehicles. Because people want more environmental material than glass fiber, there are certain needs of finding safe and economical insulating material. We checked the flammability of some kinds insulators such as PE foam, neoprene rubber foam. melamine foam and glass fiber. You could find out the characteristics such as oxygen index. optical smoke density, toxicity index of that insulators.

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The correlationship between mandibular radiomorphometric indices in panorama and bone mineral density in Cu-equivalent image of intraoral film (파노라마방사선사진에서 골형태 계측과 구내표준필름에서 구리당량치의 상관관계)

  • Kim Jae-Duk
    • Imaging Science in Dentistry
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    • v.33 no.3
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    • pp.131-135
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    • 2003
  • Purpose: To determine whether the mandibular radiomorphometric indices in panoramic radiography are correlated with the bone mineral density of Cu-equivalent images in intraoral film. Materials and Methods: The bone mineral density (BMD) of the mandibular premolar area was measured in the Cu-equivalent image of intraoral film. The Panoramic Mandibular Index (PMI) and Mandibular Cortical Width (MCW) were measured in panoramic radiographs of six dry mandibles, and the Pearson correlation between PMI, MCW, and BMD were tested. Results: There were no significant correlations between PMI and BMD (r = 0.280), nor between MCW and BMD (r =0.237). Conclusion: The results show that PMI and MCW were poor diagnostic indicators of mandibular BMD in the six dry mandibles used in this study. The correlationship between the mandibular radiomorphometric indices (PMI and MCW) and mandibular BMD needs to be researched further using large in vivo patient samples.

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Study on SiN and SiCN film production using PE-ALD process with high-density multi-ICP source at low temperature

  • Song, Hohyun;Seo, Sanghun;Chang, Hongyoung
    • Current Applied Physics
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    • v.18 no.11
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    • pp.1436-1440
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    • 2018
  • SiN and SiCN film production using plasma-enhanced atomic layer deposition (PE-ALD) is investigated in this study. A developed high-power and high-density multiple inductively coupled plasma (multi-ICP) source is used for a low temperature PE-ALD process. High plasma density and good uniformity are obtained by high power $N_2$ plasma discharge. Silicon nitride films are deposited on a 300-mm wafer using the PE-ALD method at low temperature. To analyze the quality of the SiN and SiCN films, the wet etch rate, refractive index, and growth rate of the thin films are measured. Experiments are performed by changing the applied power and the process temperature ($300-500^{\circ}C$).

Microbial Fertilizer Containing Lactobacillus fermentum Improved Creeping Bentgrass Density (유산균(Lactobacillus fermentum) 함유 미생물제제의 크리핑 벤트그래스 밀도개선 효과)

  • Jo, Gi-Woong;Kim, Young-Sun;Ham, Soun-Kyu;Bae, Eun-Ji;Lee, Jae-Pil;Kim, Doo-Hwan;Kim, Woo-Sung;Lee, Geung-Joo
    • Weed & Turfgrass Science
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    • v.6 no.4
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    • pp.322-332
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    • 2017
  • Microbial fertilizer has been used to prompt turfgrass growth and quality and to prevent turfgrass diseases in turfgrass management of golf courses. This study was conducted to evaluate effects of microbial fertilizer containing Lactobacillus fermentum (MFcL) on changes of turfgrass quality and growth by investigating turf color index, chlorophyll index, clipping yield, and nutrient content in the turfgrass tissue. Treatments were designed as follows; non-fertilizer (NF), control fertilizer (CF), MFcL treatments [CF+$1.0g\;m^{-2}$(MFL), CF+$2.0g\;m^{-2}$ (2MFL)], and only MFcL treatment (OMF; $1.0g\;m^{-2}$ MFL). Chemical properties of soil by application of MFcL was unaffected. Turf color index, chlorophyll index, clipping yield and nutrient content and uptake of MFcL treatments were similar to CF. Furthermore, turfgrass shoot density of MFL was increased by 20% than that of CF, and that of OMF by 22% than NF. These results show that the application of microbial fertilizer containing L. fermentum increased turfgrass shoot density, which is not attributed to nutrient uptake in this study, but needs to be further investigated with other mechanisms such as biostimulant induction or phytohormone production.

Augmentation of Pyriform Margin Using Porous High-Density Polyethylene Sheet In Unilateral Cleft Lip Nasal Deformity (일측성 구순열비변형에서 다공성 폴리에틸렌 판을 이용한 상악골이상구증대술)

  • Han, Ki Hwan;Kim, Jin Han;Choi, Tae Hyun;Kim, Jun Hyung;Son, Dae Gu
    • Archives of Plastic Surgery
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    • v.35 no.4
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    • pp.431-438
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    • 2008
  • Purpose: The common deformity after the correction of unilateral cleft lip nasal deformity is nasal asymmetry, and it is caused by the hypoplasia of the pyriform aperture. To correct this, many procedures have been applied, but still many problems are present. Authors performed the inlay and onlay insertion of porous high density polyethylene sheet(1 mm thickness $Medpor{(R)}$ sheet) in the hypoplastic pyriform margin of cleft side and obtained satisfactory results. Methods: 11 cases were performed and the mean follow up period was 15.1 months. Their mean age was 23.6 years. Under general anesthesia, bilateral pyriform margin was exposed. $Medpor{(R)}$ sheets in "match stick" like shaped were inlay inserted, and kidney shaped were onlay inserted fixating with two 6 mm titanium screws. After the surgery, the results was evaluated by photogrammetric analysis. On the basal view, the distance from the subalare and labiale superius' to the transverse baseline connecting the both cheilions was measured from the cleft side and the non-cleft side. Then, the postoperative symmetry was assessed by obtaining the cleft side against the non-cleft side as proportion index, defined as lateral and medial upper lip contour index. Results: There were 2 infections. The cause was because the inserted implant was too long and thus protruded to the base of nasal cavity. The lateral upper lip contour index was from 95.49 to 103.27, and medial upper lip contour index was from 90.92 to 100.49, it was statistically increased, and thus the symmetry was improved. However clinically mild depression remained at nostril floor. Conclusion: Authors performed porous high density polyethylene sheet inlay and onlay insertion for the hypoplasia of the pyriform margin in unilateral cleft lip nasal deformity. It was found that depressed pyriform margin and upper lip were corrected effectively except for the nostril floor, for which an additional soft tissue augmentation would be necessary. The inlay insertion has risk of protrusion, thus the guideline of the use of artificial prosthesis should be observed strictly.

The Study on Application of Regional Frequency Analysis using Kernel Density Function (핵밀도 함수를 이용한 지역빈도해석의 적용에 관한 연구)

  • Oh, Tae-Suk;Kim, Jong-Suk;Moon, Young-Il;Yoo, Seung-Yeon
    • Journal of Korea Water Resources Association
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    • v.39 no.10 s.171
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    • pp.891-904
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    • 2006
  • The estimation of the probability precipitation is essential for the design of hydrologic projects. The techniques to calculate the probability precipitation can be determined by the point frequency analysis and the regional frequency analysis. The regional frequency analysis includes index-flood technique and L-moment technique. In the regional frequency analysis, even if the rainfall data passed homogeneity, suitable distributions can be different at each point. However, the regional frequency analysis can supplement the lacking precipitation data. Therefore, the regional frequency analysis has weaknesses compared to parametric point frequency analysis because of suppositions about probability distributions. Therefore, this paper applies kernel density function to precipitation data so that homogeneity is defined. In this paper, The data from 16 rainfall observatories were collected and managed by the Korea Meteorological Administration to achieve the point frequency analysis and the regional frequency analysis. The point frequency analysis applies parametric technique and nonparametric technique, and the regional frequency analysis applies index-flood techniques and L-moment techniques. Also, the probability precipitation was calculated by the regional frequency analysis using variable kernel density function.

Body mass index(BMI) and lipid metabolism in patients admitted in long-term care hospitals (요양병원 입소 환자의 신체질량지수와 지질대사)

  • Park, Yoon-Jin;Lee, Su-Jung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.267-274
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    • 2017
  • This is a non-experimental and retrospective study aimed at determining the effects of long-term hospitalization on the body mass index (BMI) and lipid metabolism in long-term hospitalized patients. The study subjects included 120 patients aged 40-65 years who were hospitalized for >3 months in 2 long-term care hospitals in Gyeonggi-do, South Korea. In this study, the BMI and levels of total cholesterol, triglycerides (TG), high-density lipoprotein (HDL), and low density lipoprotein (LDL) at admission and 3 months after hospitalization were compared and analyzed, and the related changes over time were followed up. The general characteristics of the subjects were analyzed by using descriptive statistics and frequency analysis. In addition, logistic regression analysis was performed to determine the effects of the general characteristics on the BMI and Dyslipidemia. The changes in the BMI and blood lipid levels between admission and 3 months after hospitalization were analyzed using the paired t-test. The results showed that with regard to the changes in the blood lipid levels, the triglyceride levels significantly increased 3 months after hospitalization (p<.05). These findings imply that long-term hospitalization for care and rehabilitation after acute-phase treatment should be considered a potential high-risk factor for dyslipidemia, which could be prevented or alleviated by providing the patients with health education, including exercise and dietary education.

Development of a New Cluster Index for Semiconductor Wafer Defects and Simulation - Based Yield Prediction Models (변동계수를 이용한 반도체 결점 클러스터 지표 개발 및 수율 예측)

  • Park, Hang-Yeob;Jun, Chi-Hyuck;Hong, Yu-Shin;Kim, Soo-Young
    • Journal of Korean Institute of Industrial Engineers
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    • v.21 no.3
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    • pp.371-385
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    • 1995
  • The yield of semiconductor chips is dependent not only on the average defect density but also on the distribution of defects over a wafer. The distribution of defects leads to consider a cluster index. This paper briefly reviews the existing yield prediction models ad proposes a new cluster index, which utilizes the information about the defect location on a wafer in terms of the coefficient of variation. An extensive simulation is performed under a variety of defect distributions and a yield prediction model is derived through the regression analysis to relate the yield with the proposed cluster index and the average number of defects per chip. The performance of the proposed simulation-based yield prediction model is compared with that of the well-known negative binomial model.

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