• Journal of Power System Engineering
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• v.5 no.2
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• pp.22-29
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• 2001

This paper represents axial mean velocity, turbulent kinetic energy and swirl number based on momentum flux measured in the X-Y plane and Y-Z plane respectively of a cone type gas swirl burner by using X-probe from the hot-wire anemometer system. This experiment is carried out at flow rates 350 and $450{\ell}/min$ respectively, which are equivalent to the combustion air flow rate necessary for heat release 15,000 kcal/hr in gas furnace, in the test section of a subsonic wind tunnel. Axial mean velocities and turbulent kinetic energies show that their maximum values exist centering around narrow slits situated radially on the edge of and in the forefront of a burner until $X/R{\fallingdotseq}1.5$, but they have a peculiar shape like a starfish diffusing and developing into inward and outward of a burner by means of the mixing between flows ejected from narrow slits, an inclination baffle plate and swirl vanes respectively according to downstream regions. Moreover, they show a relatively large value in the inner region of 0.5$S_m$ obtained by integration of velocity profiles shows a characteristic that has an inflection point composing of the maximum and minimum value until X/R<3, but shows close agreement with the geometric swirl number after a distance of X/R=3.

• The Journal of Korean Physical Therapy
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• v.25 no.2
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• pp.96-102
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• 2013

Purpose: The purpose of the study was to investigate the effect of a training program using virtual reality on the balance and lower muscular strength of Parkinson's disease patients. Methods: The study included 22 patients with Parkinson's disease who were arbitrarily classified into 2 groups: 11 patients in the experimental group and 11 patients in the control group. Balance was measured with the Berg balance scale (BBS), the functional reach test (FRT), one-leg stance test (OLST), and the timed up and go test (TUG); whereas, lower muscular strength was measured with the sit-to-stand test (STS). Ping-Pong, bowling, and tennis were selected for virtual reality training for the experimental group, and were performed for 30 minutes 3 times a week for 8 weeks. The control group did not undergo any of the virtual reality training programs. Results: A significant difference was observed in the BBS, FRT, OLST, TUG, and STS results within the experimental group that underwent the virtual reality training program. On the other hand, no significant difference was observed in the BBS, FRT, OLST, TUG, and STS values within the control groups. Conclusion: In conclusion, the virtual reality training program positively affects the balance and lower muscular strength in Parkinson's disease patients. This result indicates the possibility of application of the virtual reality training program to the management for Parkinson's disease patients, and highlights the need for the development and application of more efficient virtual reality training programs in the future.

• Wind and Structures
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• v.23 no.2
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• pp.91-107
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• 2016

Flow-excited acoustic resonance in ducted cavities can produce high levels of acoustic pressure that may lead to severe damage. This occurs when the flow instability over the cavity mouth, which is created by the free shear layer separation at the upstream edge, is coupled with one of the acoustic modes in the accommodating enclosure. Acoustic resonance can cause high amplitude fluctuating acoustic loads in and near the cavity. Such acoustic loads could cause damage in sensitive applications such as aircraft weapon bays. Therefore, the suppression and mitigation of these resonances are very important. Much of the work done in the past focused on the fluid-dynamic oscillation mechanism or suppressing the resonance by altering the edge condition at the shear layer separation. However, the effect of the downstream edge has received much less attention. This paper considers the effect of the impingement edge geometry on the acoustic resonance excitation and Strouhal number values of the flow instabilities in a ducted shallow cavity with an aspect ratio of 1.0. Several edges, including chamfered edges with different angles and round edges with different radii, were investigated. In addition, some downstream edges that have never been studied before, such as saw-tooth edges, spanwise cylinders, higher and lower steps, and straight and delta spoilers, are investigated. The experiments are conducted in an open-loop wind tunnel that can generate flows with a Mach number up to 0.45. The study shows that when some edge geometries, such as lower steps, chamfered, round, and saw-tooth edges, are installed downstream, they demonstrate a promising reduction in the acoustic resonance. On the other hand, higher steps and straight spoilers resulted in intensifying the acoustic resonance. In addition, the effect of edge geometry on the Strouhal number is presented.

• Advances in concrete construction
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• v.10 no.5
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• pp.381-391
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• 2020

This study aimed to develop reference materials (RMs) for mortar that can simulate the initial flow characteristics with constant quality over a long period. Through the previous research on the development of RMs for cement paste, the combination of limestone, glycerol, and water was used as the basic matrix for developing RMs for mortar in this study. In addition, glass beads of three particle sizes (0.5, 1.0, and 2.0 mm) and ISO standard sand were selected as tentative candidates to derive fine aggregate substitutes. The mixture of glass beads could simulate the initial flow characteristics of mortar, but under the same mixing ratio, replicates showed an unstable tendency to indicate inconsistent values due to the generation of electrostatic properties between materials and equipment. On the other hand, the mixture using ISO standard Sand not only simulates the constant flow characteristics for a long period of time, but also shows stable results with little error in replicates. Therefore, limestone, glycerol, ISO standard sand, and water were finally determined as components that met the required properties of RMs for mortar. The effect of each component on the flow characteristics of RMs was analyzed. It was found that glycerol increased the cohesion between the particles of standard sand, resulting in a constant increase both in the plastic viscosity and yield stress. Both limestone and standard sand had a dominant effect on the yield stress. The relationships between various mortar mixing ratios and the corresponding mixing ratios of RMs were established. In addition, the results of the verification experiment showed that the rheological properties of the RMs obtained through the relationships correlated with various water/cement ratios and the fine aggregate volume fractions of mortar obtained with same manner. In other words, the RMs for mortar developed in this study can be used as standard samples because they can simulate the initial flow characteristics of mortar of various mixing ratios for a long period without any chemical changes.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1049-1053
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• 1999

Chopped wheat straw (0.5-1.5 cm) was subjected to different treatment combinations in a $5{\times}4$ factorial arrangement involving the five levels of urea (0, 2, 3, 4 and 5%, w/w) and four levels of lime (0, 2, 4 and 6%, w/w) at 50% moisture and kept for 3 wk reaction period at about $35{^{\circ}C}$ in laboratory. Treated wheat straw samples were analyzed to study the associative effect of urea and lime on chemical composition, in sacco and in vitro digestibilities. Results showed that cell wall constituents (CWC) solubilized significantly (p<0.01) due to urea and lime treatment on one hand and substantially increase the crude protein (CP) on the other in wheat straw. The main effect on synergism of both chemicals was noticed on organic matter (OM), neutral detergent fibre (NDF), hemicellulose (HC), acid detergent lignin (ADL) and silica by solubilising their contents as a result of considerable increase in cell contents in treated wheat straw. The respective decreases were 5.45, 13.0, 37.23, 44.95 and 26.16% in different treatment combinations. The most interesting feature of the treatment was evident by increase in ash content on each level of lime application. CP content increase up to 12.78% due to urea treatment in comparison with untreated wheat straw (2.56%). The effect of solubilization of structural carbohydrates and increased crude protein due to synergistic effect of urea and lime were clearly seen on improved digestibility of OM and DM. The increase in ISOMD, ISDMD, and IVDMD were 21.67, 21.67, 16.24, and 17.5 units. The increase in digestibility were relative to additions of both chemicals and digestibility values increased with increasing levels of urea plus lime concentration in different treatment combination. The maximum improvement was noticed at 4% urea and 4% lime levels at 50% moisture for 3 wk reaction period in treated wheat straw.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1577-1581
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• 2016

Tobacco use is a well-established risk factor for many types of cancers. Recent data on selected cancer incidence and mortality related to smoking in the Indonesian population are provided in this study. Morbidity and mortality data were derived from GLOBOCAN 2012 and the population attributable fraction (PAF) was estimated using the standard methodology developed by the World Health Organization. Using these data, we calculated disability adjusted life year (DALY) values for smoking-related cancer. The DALY was estimated by summation of the years lived with disability (YLD) and years life lost due to premature death (YLL). The cancer cases related to smoking in Indonesia numbered 45,132, accounting for 35,580 cancer deaths. The morbidity and mortality of lung cancer can be considered as the highest priority in both men and women. Furthermore the greatest YLD due to smoking in Indonesian men and women were from pancreas and lung cancers. For YLL among men, the highest years lost were from lung and liver cancers. On the other hand, among women lung oral cavity and lip were most important. Based on the DALY indicator, burden priorities for Indonesian men were lung cancer (298,980), liver cancer (60,367), and nasopharynx (46,185), while among Indonesian women they were lung cancer (34,119), cervix uteri (9,213) and pancreas cancer (5,433). In total, Indonesian burden of cancers attributed to smoking was 638,682 DALY. This study provides evidence about the burden of cancers caused by smoking as a rational basis for initiating national tobacco control policies in Indonesia.

• The Research Journal of the Costume Culture
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• v.15 no.6
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• pp.929-938
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• 2007

The purpose of this study was to explore the consumers' purchasing pattern and dissatisfaction with the quality of the jean pants. A total of 695 men and women completed the questionnaire. The questionnaire for the survey measured consumer's jean pants purchasing pattern and dissatisfaction for quality. The results of this study showed that men bought higher priced jeans. Women in their twenties purchased and worn jeans frequently and men and women in age 20s mainly bought jeans at wholesale stores or department stores; but, majority of subjects in their thirties bought jeans at discount stores. Consumer's dissatisfaction with the quality of jean pants was significantly different among the groups by age, gender or their pursuing buying benefit. The men and women in age 30s were dissatisfied with harshness of the denim fabric. The subjects, who highly concerned on the aesthetic value, were dissatisfied with the inconsistence color of the jean pants after washing. Men and women who valued the functional performance of jean pants, were dissatisfied with low sweat absorbancy of jean pants material. The results of this study showed that the consumer's buying pattern for jean pants were differentiated by their age and gender. These results imply that jean pants manufacturers should develop jean pants to meet the needs of their target market. The jean pants, which were manufactured for discount stores, should be made of fabrics with good sweat absorbancy and soft hand. The fashion jean pants, which were targeted for women seeking aesthetic values, should be improved to maintain color consistency of the fabric.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.133-144
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• 2014

This study was carried out to review the pattern of forest stand development for six Gangwondo Baekdudaegan Mountains which experienced different type and duration of intensive legal protection. Vegetation data from point sampling method were employed to classify community types by cluster analysis on the basis of the importance values of canopy tree species for the study areas. The names of classified communities were given by the composition of dominant tree species. The communities were also compared one another in terms of stand structure by species diversity index. The results indicated that National Parks (Seoraksan and Odaesan) had greater proportion of mixed mesophytic forest type which was supposed to progress further forest succession process so as to have more complex and diversified stand structure. On the other hand, ordinary forest areas (Seokbyeongsan and Deokhangsan) had greater proportion of the forest types which was dominatively composed of Quercus mongolica and Pinus densiflora. The forest types with large amount of these two species would tend to develop for relatively short period of time of 40-50 years after artificial disturbances. Hyangnobong of Natural Protection Area and Hambaeksan of Natural Ecosystem Conservation Area showed intermediate stand development pattern in between National Parks and ordinary forest areas. The period of intensive legal protection of the forest area was positively correlated with species diversity index (R=0.736), and noted that the forest which received intensive protection regulation for longer period tended to show more complex and diversified stand structure.

• Korean Journal of Ichthyology
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• v.18 no.2
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• pp.129-140
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• 2006

To find out the seasonal variation of species composition and distribution of fish eggs and larvae in the western part of Jeju Island, investigations were carried out with plankton net during five different months from September 2004 to August 2005. The mean abundance of fish eggs and larvae showed a maximum values in summer (August). During the survey period, total 59 species (51 genus, 26 families and 10 orders) of fish larvae were identified. Among the 10 orders, Perciformes (41 species, 15 families), Scorpaeniformes (7 species, 2 families) and Gasterosteiformes (2 species, 2 families) were the dominant species in this study area. The number of species was higher in high water temperature period than in low one, showing a peak in August as 25 species, and the lowest in May as 6 species. Engraulis japonicus, Scomber japonicus and Scombridae spp. which were migratory fish species occurred abundantly in summer. On the other hand, Sebastiscus marmoratus and Sebastes inermis which were sedentary fish species occurred abundantly in winter.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.25-28
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• 1999

Consider connection-oriented wireless cellular net-works. To establish a circuit or virtual circuit in such a network, a paging message is broadcast over a region at which the destined mobile station is presumed to reside, (identified as a paging area). For an effective paging mechanism, it is desirable to provide the location information of mobile stations to the network. In this paper, we consider a mobile controlled location update scheme under which each mobile station periodically reports its current location information to the network by using an inherent timer (without measuring the power of signals transmitted from base stations). Based on the latest information about a mobile station's location, a paging area is selected to page the mobile station. Note that under this scheme, a mobile station may not yet have reported its location change while sojourning out of the current paging area. In such situation, the mobile station can not receive a paging message destined to it. Frequent location updates can reduce the paging failure rate incurred by mobile stations'sojourning out of the paging area. However, larger bandwidth is needed for location update as the location update rate is increased. On the other hand, as the size of the paging area is increased, the paging failure rate is decreased, while larger bandwidth is required for paging. Thus, we first present a model for mobility, paging and location update processes, and secondly investigate the effect of network parameters on the paging failure rate and the amount of bandwidth used for paging and location update. Finally, we formulate problems to find proper values for the location update rate and paging area size under the constraints on the bandwidth usage levels for location update and paging.