• Journal of Korean Society of Transportation
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• v.17 no.2
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• pp.105-114
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• 1999

The pattern of traffic streams in residential streets is different from the ordinary roads separated by pedestrian and car lanes. Such fact makes it difficult to evaluate the new counter-measures with existing indices and methods. In this study, a unified, consistent new method is introduced as Time-Space Occupancy (TSO) concept. An application of TSO concept will suggest a TSO exposure volume index which can show the decree of danger in residential streets where vehicles, pedestrian and other traffic streams are interacted. The validity of TSO exposure volume index will be verified through the survey conducted in Seoul and the subjects will be the residents who live at various kinds of residential streets.

• Geomechanics and Engineering
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• v.2 no.4
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• pp.321-335
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• 2010

This article describes a laboratory research on stabilizing tropical peat using ordinary Portland cement (OPC) as a binding agent, and polypropylene and steel fibres as chemically inert additives. California bearing ratio (CBR) and unconfined compressive strength (UCS) tests were carried out to evaluate the increase in the strength of the stabilized samples compacted at their optimum moisture contents and air cured for up to 90 days. The results show that the UCS values of stabilized peat samples increased by as high as 748.8% by using OPC (5%), polypropylene fibres (0.15%), and steel fibres (2%). The CBR values of the samples stabilized with OPC (5%), polypropylene fibres (0.15%), and steel fibres (4%) showed an increase of as high as 122.7%. The stabilized samples showed a shrinkage in volume upon air curing and this shrinkage was measured by an index called, volume shrinkage index (VSI). The highest VSI recorded was 36.19% for peat without any additives; and the minimum was 0% for the sample containing 30% OPC, 0.15% polypropylene fibres and 2% steel fibres. The technique of stabilizing peat with OPC, polypropylene and fibres, coupled with air curing, appears to be cost-effective compared with other frequently used techniques.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.972-975
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• 2004

In order to reduce the noise of BLDC motor, a systematic optimization procedure for rotor structure is presented. The noise index is defined as the sum of volume velocity of FE-model that are calculated at the dominant frequencies during dehydration process, which is based on the principle of radiation simple volume source. Then, the five design variables are selected to represent the shape and layout or rotor structure. This discrete design optimization problem for minimizing the noise index is solved by 3-level orthogonal array based effect analysis. Finally, the response surface method (RSM) combined optimization approach is employed for more refining the approximate optimum.

• The Korean Journal of Food And Nutrition
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• v.32 no.2
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• pp.79-88
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• 2019

This study was conducted to evaluate the characteristics of bread and the rheology of flour dough containing jochung. In the farinogram test, the addition of jochung changed water absorption, development time and mixing tolerance index for making bread As the amount of jochung increased, the water absorption, mixing tolerance index decreased and the development time increased. In the extensograph test, the degree of extension decreased with increasing of jochung content whereas degree of resistance was enhanced with addition of jochung. After fermentation treatment, the volume of the dough with 20% sucrose were less than that of the dough containing 20% of jochung. The dough with 5% jochung showed the lowest dough raising power compared to the other doughs. The bread consisting of 15% jochung showed the highest volume of loaf and specific volume. Therefore, high quality of bread can be achieved by adding jochung instead of sucrose for making bread.

• Journal of radiological science and technology
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• v.47 no.2
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• pp.125-135
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• 2024

This study analysed the factors that predict and influence heart disease through key indicators related to changes in left atrial and left ventricular size. Measurements recommended by the American Society of Echocardiography were used, and the influence of variables was assessed using multiple regression analysis. The results showed that left atrial volume index(LAVI) was significantly different by age, obesity, diabetes, hypertension, dyslipidaemia, and left ventricular relaxation dysfunction(p<0.05). Left ventricular mass index(LVMI) was significantly different according to age, body mass index, hypertension, diabetes, dyslipidaemia, and left ventricular relaxation dysfunction(p<0.05). Increases in LVMI and relative ventricular wall thickness(RWT) were associated with changes in LAVI(p<0.05). Age, systolic blood pressure, increased LAVI, and RWT influenced changes in LVMI, and left ventricular dysfunction was analysed as an influencing factor for both changes in LAVI and LVMI. Therefore, changes in left atrial and left ventricular size are indicators for early diagnosis and prevention of heart disease, and it is necessary to carefully observe structural changes in the heart and actively manage risk factors for the prevention and management of heart disease.

• Journal of Periodontal and Implant Science
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• v.43 no.5
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• pp.233-242
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• 2013

Purpose: Peri-implant sulcular fluid (PISF) has a production mechanism similar to gingival crevicular fluid (GCF). However, limited research has been performed comparing their behavior in response to inflammation. Hence, the aim of the present study was to comparatively evaluate PISF and GCF volume with varying degrees of clinical inflammatory parameters. Methods: Screening of patients was conducted. Based on the perimucosal inflammatory status, 39 loaded implant sites were selected from 24 patients, with equal numbers of sites in healthy, peri-implant mucositis, and peri-implantitis subgroups. GCF collection was done from age- and sex-matched dentate patients, selected with gingival inflammatory status corresponding to the implant sites. Assessment of the inflammatory status for dental/implant sites was performed using probing depth (PD), plaque index/modified plaque index (PI/mPI), gingival index/simplified gingival index (GI/sGI), and modified sulcular bleeding index (BI). Sample collection was done using standardized absorbent paper strips with volumetric evaluation performed via an electronic volume quantification device. Results: Positive correlation of the PISF and GCF volume was seen with increasing PD and clinical inflammatory parameters. A higher correlation of GCF with PD (0.843) was found when compared to PISF (0.771). PISF expressed a higher covariation with increasing grades of sGI (0.885), BI (0.841), and mPI (0.734), while GCF established a moderately positive correlation with GI (0.694), BI (0.696), and PI (0.729). Conclusions: Within the limitations of this study, except for minor fluctuations, GCF and PISF volumes demonstrated a similar nature and volumetric pattern through increasing grades of inflammation, with PISF showing better correlation with the clinical parameters.

• Structural Engineering and Mechanics
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• v.76 no.1
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• pp.129-139
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• 2020

In this piece of work, carbon nanotubes motion equations are framed by Kelvin's method. Employment of the Kelvin's method procedure gives birth to the tube frequency equation. It is also exhibited that the effect of frequencies is investigated by varying the different index of polynomial function. By using volume fraction for power law index, the fundamental natural frequency spectra for two forms of single-walled carbon nanotubes are calculated. The influence of frequencies against length-to-diameter ratios with varying power law index are investigated in detail for these tubes. Throughout the computation, it is observed that the frequency behavior for the boundary conditions follow as; clamped-clamped, simply supported-simply supported and these frequency curves are higher than that of clamped-free curves. Computer software MATLAB is utilized for the frequencies of single-walled carbon nanotubes.

• Journal of Sensor Science and Technology
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• v.16 no.4
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• pp.254-258
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• 2007

A novel cure sensor based on the side-polished single mode fiber has been proposed and demonstrated. Two different UV curable epoxies were used to verify the feasibility of the side-polished single mode fiber as a high sensitivity cure sensor. The volume change of the epoxy by UV curing results in a corresponding change of the refractive index. The sensor can be used to monitor the curing process, the refractive index variation and the volume change of epoxy in real time during the UV curing process. In addition, small birefringence of the epoxy film can be detected using the sensor.

• Bulletin of the Korean Chemical Society
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• v.15 no.2
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• pp.106-112
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• 1994

Six physical properties (molecular weight, heat capacity, side chain weight, side chain volume, standard entropy and partial molar volume) of amino acids, peptides and their derivatives were examined by molecular modeling techniques. The molecular connectivity index, Wiener distance index and ad hoc descriptor are employed as structural parameters to encode information about branching, size, cyclization, unsaturation, heteroatom content and polarizability. This paper examines the correlation of the molecular modeling techique's parameters and the physicochemical properties of amino acids and their derivatives. As a result, calculated values were in agreement with experimental data in the above six physical properties of amino acids, peptides and their derivatives and the molecular connectivity index was superior to the other indices in fitting the calculated data.

• Journal of Magnetics
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• v.18 no.3
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• pp.276-282
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• 2013

In this paper, magnetic flux distributions of several permanent magnet arrays, including Halbach array, are analyzed and compared. Also, braking force characteristics on a moving solid conductor in the eddy current brake systems with such magnet arrays are analyzed. Then, a new performance index taking into account the maximum braking force and the volume of the magnet is introduced for the comparison and case study of permanent magnet arrays. By changing the lengths, magnetization directions and the height of the permanent magnet arrays, a higher braking force per volume of the magnet can be achieved.