• Title/Summary/Keyword: non-formulas

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Simple equations for the calculation of the temperature within the cross-section of slim floor beams under ISO Fire

  • Zaharia, R.;Franssen, J.M.
    • Steel and Composite Structures
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    • v.13 no.2
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    • pp.171-185
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    • 2012
  • The calculation of fire resistance for a composite structural element comprises the calculation of the temperature within its cross-section and of the load bearing capacity, considering the evolution of the steel and concrete mechanical properties, function of the temperature. The paper proposes a method to calculate the bending capacity under ISO fire, for Slim Floor systems using asymmetric steel beams, with a wider lower flange or a narrow upper flange welded onto a half hot-rolled profile. The temperatures in the cross-section are evaluated by means of empirical formulas determined through a parametrical analysis, performed with the special purpose non-linear finite element program SAFIR. Considering these formulas, the bending capacity may be calculated, using an analytical approach to determine the plastic bending moment, for different fire resistance demands. The results obtained with this simplified method are validated through numerical analysis.

A study on practical method to estimate drag of super-cavitating underwater vehicles

  • Choi, Jung-Kyu;Kim, Hyoung-Tae
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.13 no.1
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    • pp.817-832
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    • 2021
  • In this paper, a simple practical method to estimate the drag of Super-Cavitating Underwater Vehicles (SCUV) is proposed that can obtain the drag with only principal dimensions in an initial design stage. SCUV is divided into cavitator, forebody, afterbody, base, and control fin and the drag of each part is estimated. The formulas for the drag coefficient are proposed for the disk and cone type cavitators and wedges used as control fins. The formulas are a function of cavitation number, cone or wedge angle, and Reynolds number. This method can confirm the drag characteristics of SCUV that the drag hump appears according to the coverage of the body by the cavity and the cavitator drag remains only when the entire body is covered by cavity. Applying this method to SCUV of various shapes, it is confirmed that the effects of cavitating and non-cavitating conditions, cavitator and body shape, and speed could be found.

Research on Cyber-terrorism preparation scheme (사이버테러 대응방안에 관한 연구)

  • Kim, Yeon Jun;Kim, Sang Jin
    • Convergence Security Journal
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    • v.16 no.3_2
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    • pp.33-42
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    • 2016
  • While evolving information-oriented society provides a lot of benefits to the human life, new types of threats have been increasing. Particularly, cyber terrorism, happen on the network that is composed of a computer system and information communication network, and the mean and scale of damage has reached a serious level. In other words, it is hard to locate cyber terror since it occurs in the virtual space, not in the real world, so identifying "Who is attacking?" (Non-visibility, non-formulas), or "Where the attack takes place?" (trans-nation) are hard. Hackers, individuals or even a small group of people, who carried out the cyber terror are posing new threats that could intimidate national security and the pace and magnitude of threats keep evolving. Scale and capability of North Korea's cyber terrorism are assessed as world-class level. Recently, North Korea is focusing on strengthen their cyber terrorism force. So improving a response system for cyber terror is a key necessity as North Korea's has emerged as a direct threat to South Korean security. Therefore, Korea has to redeem both legal and institutional systems immediately to perform as a unified control tower for preemptive response to cyber terrors arise from North Korea and neighboring countries.

Behavior of symmetrically haunched non-prismatic members subjected to temperature changes

  • Yuksel, S. Bahadir
    • Structural Engineering and Mechanics
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    • v.31 no.3
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    • pp.297-314
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    • 2009
  • When the temperature of a structure varies, there is a tendency to produce changes in the shape of the structure. The resulting actions may be of considerable importance in the analysis of the structures having non-prismatic members. Therefore, this study aimed to investigate the modeling, analysis and behavior of the non-prismatic members subjected to temperature changes with the aid of finite element modeling. The fixed-end moments and fixed-end forces of such members due to temperature changes were computed through a comprehensive parametric study. It was demonstrated that the conventional methods using frame elements can lead to significant errors, and the deviations can reach to unacceptable levels for these types of structures. The design formulas and the dimensionless design coefficients were proposed based on a comprehensive parametric study using two-dimensional plane-stress finite element models. The fixed-end actions of the non-prismatic members having parabolic and straight haunches due to temperature changes can be determined using the proposed approach without necessitating a detailed finite element model solution. Additionally, the robust results of the finite element analyses allowed examining the sources and magnitudes of the errors in the conventional analysis.

Stimulation of the Immune Response by Herbal Formulas for Wind-Cold and Heat Pain Symptom (대표적인 풍한열(風寒熱)에 의한 통증 치료 처방의 면역 활성화 비교 연구)

  • Jung, Da-Young;Ha, Hye-Kyung;Lee, Ho-Young;Lee, Jin-Ah;Lee, Jun-Kyoung;Huang, Dae-Sun;Shin, Hyeun-Kyoo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.24 no.4
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    • pp.616-623
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    • 2010
  • Three herbal formulas (Bangpungtongsung-san, Ohyaksungi-san, and Ojeok-san) for wind-cold and heat pain symptom were applied to investigate the immunological activities on antigen (Ag)-specific or Ag-non-specific immune responses in murine macrophage cell line (RAW 264.7) and ovalbumin (OVA)-immunized mice. This study was carried out in nitric oxide (NO) synthesis in RAW 264.7 cells and cellular proliferation in mouse splenocytes according to three herbal formulas. C57BL/6 mice were immunized intraperitonially with OVA/aluminium ($100\;{\mu}g/200\;{\mu}g$/mouse) on day 1, 8, and 15. Three herbal formulas were administrated to mice orally for 3 weeks from day 1. On day 22, OVA-, lipopolysaccharide (LPS)-, and concanavalin A (Con A)-stimulated splenocyte proliferation and antibodies (OVA-specific antibodies of the IgG, lgG1, and total IgM classes) in plasma were measured. Ohyaksungi-san increased NO synthesis in RAW 264.7 cells. Ojeok-san and Ohyaksungi-san significantly enhanced cellular proliferation by LPS and Con A in splenocytes from OVA-immunized mice (p<0.001). Three herbal formulas for wind-cold and heat pain symptom also significantly enhanced plasma OVA-specific IgG, IgG1, and total IgM levels compared with the OVA/Alum group. These results suggested that three herbal formulas for wind-cold and heat pain symptom could be used as stimulator of immune response.

TcellInflamedDetector: an R package to distinguish T cell inflamed tumor types from non-T cell inflamed tumor types

  • Yang, San-Duk;Park, Hyun-Seok
    • Genomics & Informatics
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    • v.20 no.1
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    • pp.13.1-13.4
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    • 2022
  • A major issue in the use of immune checkpoint inhibitors is their lack of efficacy in many patients. Previous studies have reported that the T cell inflamed signature can help predict the response to immunotherapy. Thus, many studies have investigated mechanisms of immunotherapy resistance by defining the tumor microenvironment based on T cell inflamed and non-T cell inflamed subsets. Although methods of calculating T cell inflamed subsets have been developed, valid screening tools for distinguishing T cell inflamed from non-T cell inflamed subsets using gene expression data are still needed, since general researchers who are unfamiliar with the details of the equations can experience difficulties using extant scoring formulas to conduct analyses. Thus, we introduce TcellInflamedDetector, an R package for distinguishing T cell inflamed from non-T cell inflamed samples using cancer gene expression data via bulk RNA sequencing.

Accuracy of predictive equations for resting metabolic rate in Korean athletic and non-athletic adolescents

  • Kim, Jae-Hee;Kim, Myung-Hee;Kim, Gwi-Sun;Park, Ji-Sun;Kim, Eun-Kyung
    • Nutrition Research and Practice
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    • v.9 no.4
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    • pp.370-378
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    • 2015
  • BACKGROUND/OBJECTIVES: Athletes generally desire changes in body composition in order to enhance their athletic performance. Often, athletes will practice chronic energy restrictions to attain body composition changes, altering their energy needs. Prediction of resting metabolic rates (RMR) is important in helping to determine an athlete's energy expenditure. This study compared measured RMR of athletic and non-athletic adolescents with predicted RMR from commonly used prediction equations to identify the most accurate equation applicable for adolescent athletes. SUBJECTS/METHODS: A total of 50 athletes (mean age of $16.6{\pm}1.0years$, 30 males and 20 females) and 50 non-athletes (mean age of $16.5{\pm}0.5years$, 30 males and 20 females) were enrolled in the study. The RMR of subjects was measured using indirect calorimetry. The accuracy of 11 RMR prediction equations was evaluated for bias, Pearson's correlation coefficient, and Bland-Altman analysis. RESULTS: Until more accurate prediction equations are developed, our findings recommend using the formulas by Cunningham (-29.8 kcal/day, limits of agreement -318.7 and +259.1 kcal/day) and Park (-0.842 kcal/day, limits of agreement -198.9 and +196.9 kcal/day) for prediction of RMR when studying male adolescent athletes. Among the new prediction formulas reviewed, the formula included in the fat-free mass as a variable [$RMR=730.4+15{\times}fat-free\;mass$] is paramount when examining athletes. CONCLUSIONS: The RMR prediction equation developed in this study is better in assessing the resting metabolic rate of Korean athletic adolescents.

A study on the computer simulation model of the NONHOLONOMIC rotating motion system about the closed system (폐쇄된 계에서 비 흘로노믹 (NONHOLONOMIC) 회전 운동 SYSTEM에 대한 컴퓨터 씨뮬레이션 모델에 관한 연구)

  • Chung, Byung-Tae
    • Journal of the Korea Computer Industry Society
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    • v.10 no.5
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    • pp.221-226
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    • 2009
  • The closed system's internal rigid body particle rotation motion can be distinguished by a main body that becomes the core of the rotation and the particles that are subjected to the rotation. The instance of particles becoming bounded to the main body as a holonomic system, has till now, been well defined and formulated in the study of Kinetics, and the structure of the formulas relate well to reality. However, when the structure is non-holonomic it deviates from these existing equations. The purpose of this research is to categorize the differences between a holonomic system and a non-holonomic system when rotating, through devices. With a special emphasis on the real phenomenon of the non-holonomic system which will be formulated in the form of a model or computer simulation. With these formulas, the center of mass shift in a closed rotating motion system and confined motion of external friction will be adequately expressed, so that it may be applied to computer graphics motions methods.

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Microbiological Quality and Potential Pathogen Monitoring for Powdered Infant Formulas from the Local Market (영유아용 분말 조제분유의 미생물 품질분석과 위해세균 모니터링)

  • Hwang, Ji-Yeon;Lee, Ji-Youn;Park, Jong-Hyun
    • Food Science of Animal Resources
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    • v.28 no.5
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    • pp.555-561
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    • 2008
  • Ninety-nine samples of powdered infant formula in a market were collected from the local market and their contaminations for total aerobic bacteria, coliform, FAO/WHO Category A, B, and C pathogens were analyzed. Total aerobic bacteria were detected in 92 of 99 samples (93%) at levels of $1.83{\pm}0.68\;Log\;MPN/g$. These levels were below legal levels specified for infant formulas except for one sample detected by 4.5 Log CFU/g. Coliform was detected in 12 of 99 samples (12%) at levels of $1.26{\pm}1.03\;Log\;MPN/g$ whereas non-detection was required according to the specification of coliform in infant formulas. Escherichia coli was detected in 1 of 99 samples by 0.48 Log MPN/g. Salmonella and Enterobacter sakazakii among Category A weren't detected in all the samples. Enterobacteriaceae, Category B group, were detected in 25 samples of total 99 samples (25%) by $0.83{\pm}1.37\;Log\;MPN/g$. Enterobacteriaceae identified by API 20E were Escherichia vulneris, Es. hermannii, Pantoea spp., Citrobacter koseri, Klebsiella pneumoniae, En. cloaceae. Bacillus cereus among Category C was highly detected in 29 of 99 samples (29%) at levels of $0.69{\pm}0.32\;Log\;MPN/g$ with the most probable number count method, which were below legal levels for the specification of B. cereus in infant formulas. Clostridium perfringens, E. coli O157, Staphyloccus aureus, Listeria monocytogenes, Yersinia enterocolitica, and Campylobacter jejuni/coli were not detected. Contamination level of major pathogens was low and falls within the range of specification of infant formulas. However, Enterobacteriaceae and B.cereus showed the high prevalence and some Enterobacteriaceae causing disease were detected. Therefore, it is necessary to monitor the potential pathogens continually and reduce them to improve the microbial quality of non-sterilized powdered infant formulas.

Sensorless Control of Non-salient Permanent Magnet Synchronous Motor Drives using Rotor Position Tracking PI Controller

  • Lee Jong-Kun;Seok Jul-Ki
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.5B no.2
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    • pp.189-195
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    • 2005
  • This paper presents a new velocity estimation strategy for a non-salient permanent magnet synchronous motor drive without high frequency signal injection or special PWM pattern. This approach is based on the d-axis current regulator output voltage of the drive system, which contains the rotor position error information. The rotor velocity can be estimated through a rotor position tracking PI controller that controls the position error at zero. For zero and low speed operation, the PI gain of the rotor position tracking controller has a variable structure according to the estimated rotor velocity. Then, at zero speed, the rotor position and velocity have sluggish dynamics because the varying gains are very low in this region. In order to boost the bandwidth of the PI controller during zero speed, the loop recovery technique is applied to the control system. The PI tuning formulas are also derived by analyzing this control system by frequency domain specifications such as phase margin and bandwidth assignment.