• Title/Summary/Keyword: local average

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Effects of Beam Pulse Width and Power Density in Silver Nanowire Welding Using Pulsed IR Laser (적외선 레이저 공정을 통한 실버나노와이어 접합에서의 빔 펄스폭과 출력의 영향)

  • Kim, Joohan;Yoon, Sang Woo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.38 no.8
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    • pp.893-898
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    • 2014
  • A direct pulsed laser process for welding and networking silver nanowires was developed. The welded nanowire network demonstrated modified electrical properties in a transparent substance. In particular, the welding points on the nanowires were investigated to measure the resistance at the connections. The level of networking in nanowires was explored with respect to various laser pulse widths and average power densities. In particular, the influence of laser beam density was investigated in detail. Selective laser treatment can be advantageous in imparting customized local property changes in transparent conducting materials. Various applications of the process are also discussed in this paper.

Utilization of Energy and Protein in Local Indian Crossb red Gilts Fed Diets Containing Different Levels of Rice Bran

  • Soren, N.M.;Bhar, R.;Chhabra, A.K.;Mandal, A.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.5
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    • pp.688-692
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    • 2004
  • Fifty four crossbred gilts of 26.38${\pm}$0.85 kg body weight and 25 weeks of age were randomly divided into three groups, having six replicates of three animals each and were assigned to one of the three dietary treatments containing corn, wheat bran and rice bran (RB) at 35, 47 and 0% in $R_1$; 17.5, 23.5 and 41% in $R_2$ and 0, 0 and 82% in $R_3$. Soybean meal and fishmeal were used as source of protein at 10 and 6%, respectively, in all the rations. Average daily CP, DCP, DE and ME intake per kg $W^{0.75}$ and body weight gains were lowest (p<0.01) in gilts fed 82% RB ($R_3$), followed by $R_2$ and R1. Utilization of protein with respect to nitrogen balance and DCP conversion efficiency did not differ (p>0.05) between the treatment groups. All the gilts were in positive nitrogen balance. However, the excretion of dietary nitrogen and energy through faeces was higher (p<0.01) in gilts fed RB. However, the DE and ME conversion efficiency were higher (p<0.01) in gilts fed RB. Therefore, it can be concluded that the digestibility of energy and protein in diets containing rice bran goes on decreasing with the increasing level of fat and fibre, but the metabolizability of the energy and protein was better in pigs fed RB in the diet.

Characteristics of Urban Meteorology in Seoul Metropolitan Area of Korea (수도권 지역의 도시 기상 특성)

  • Kim, Yeon-Hee;Choi, Da-Young;Chang, Dong-Eon
    • Atmosphere
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    • v.21 no.3
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    • pp.257-271
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    • 2011
  • The aim of this study is to examine weather modification by urbanization and human activities. The characteristics of the urban heat island (UHI) and precipitation in Seoul metropolitan area of Korea are investigated to demonstrate that cities can change or modify local and nearby weather and climate, and to confirm that cities can initiate convection, change the behavior of convective precipitation, and enhance downstream precipitation. The data used in this study are surface meteorological station data observed in Seoul and its nearby 5 cities for the period of 1960 to 2009, and 162 Automatic Weather System stations data observed in the Seoul metropolitan area from 1998 to 2009. Air temperature and precipitation amount tend to increase with time, and relative humidity decreases because of urbanization. Similar to previous studies for other cities, the average maximum UHI is weakest in summer and is strong in autumn and winter, and the maximum UHI intensity is more frequently observed in the nighttime than in the daytime, decreases with increasing wind speed, and is enhanced for clear skies. Relatively warm regions extend in the east-west direction and relatively cold regions are located near the northern and southern mountains inside Seoul. The satellite cities in the outskirts of Seoul have been rapidly built up in recent years, thus exhibiting increases in near-surface air temperature. The yearly precipitation amount during the last 50 years is increased with time but rainy days are decreased. The heavy rainfall events of more than $20mm\;hr^{-1}$ increases with time. The substantial changes observed in precipitation in Seoul seem to be linked with the accelerated increase in the urban sprawl in recent decades which in turn has induced an intensification of the UHI effect and enhanced downstream precipitation. We also found that the frequency of intense rain showers has increased in Seoul metropolitan area.

A Study on the Decision for External Water Level of a River Considering Sea Level Rise (해수면 상승을 고려한 하천 외수위 결정에 관한 연구)

  • Choo, Tai Ho;Yun, Gwan Seon;Kwon, Yong Been;Ahn, Si Hyung;Kim, Jong Gu
    • The Journal of the Korea Contents Association
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    • v.16 no.4
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    • pp.604-613
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    • 2016
  • The sea level of the Earth is rising approximately 2.0mm per year (global average value) due to thermal expansion of sea water, melting of glaciers and other causes by global warming. However, when it comes to design a river, the standard of design water level is decided by analyzing four largeness tide value and harmonic constant with observed tidal water level. Therefore, it seems the external water level needs to consider an increasing speed of the seawater level which corresponds to a design frequency. In the present study, the hourly observed tidal water level targeting 47 tidal stations operated by Korea Hydrographic and Oceanographic Administration (KHOA) from beginning of observation to 2015 per hour has been collected. The variation of monthly and yearly and increasing ratio have been performed divided 4 seas such as the Southern, East, Western, and Jeju Sea. Also, the external water level existing design for rivers nearby a coast was been reviewed. The current study could be used to figure out the cause of local seawater rise and reflect the external water level as basic data.

Current Status and Problems of Support Polices and Legal Improvement Devices for the Aged Living Alone (독거노인에 대한 지원정책의 현황과 문제점과 법제도적 개선방안)

  • Noh, Jae-Chul;Ko, Zoon-Ki
    • The Journal of the Korea Contents Association
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    • v.13 no.1
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    • pp.257-268
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    • 2013
  • These days the aged have to live 30 or 40 years beyond the day they quit their day jobs. The quality of life for the elderly is a keen concern for the young people. We need to have a correct understanding of the age problem and the effort of a government or local government in order to bless the average life expectancy and not perceive it as a disaster. The number of the elderly living alone is increasing. Various types of support are needed to ensure that these people do not become socially isolated and are able to live alone. Supporting them includes activities to prevent social isolation that take their unique difficulties into consideration, which are different from the difficulties of supporting elderly people living with their families. In this research examined the current status of support activities for elderly people living alone and the unique difficulties involved in supporting them.

Characteristics of Ozone Concentrations around an Urban Valley based on the Intensive Air Quality Measurement during Spring and Summer of 2006 (2006년 봄, 여름철 대기오염물질 집중측정을 통한 도시 계곡지역의 오존농도 특성 분석)

  • Song, Sang-Keun;Kim, Yoo-Keun;Kang, Jae-Eun
    • Journal of Korean Society for Atmospheric Environment
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    • v.25 no.4
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    • pp.289-303
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    • 2009
  • The chemical and meteorological effects on the concentration variations of ozone ($O_3$) were evaluated based on the intensive air quality measurement (5 pollutants and aromatic volatile organic compounds (AVOCs)) in and out-side an urban valley during spring and summer of 2006. The 5 pollutants measured in the study area include $O_3$, $NO_2$, NO, $PM_{10}$, and CO; the AVOCs include benzene (BEN), toluene (TOL), ethylbenzene (EB), m,p-xylene (MPX), and o-xylene (OX). For the purpose of this study, study areas were classified into two categories: valley area (VA) with a semi-closed topography covering a number of industrial complex, public building, and mountains and non-valley area (NVA) surrounding the suburban and residential areas. In general, the mean concentration levels of most pollutants (except for $PM_{10}$) in the VA were higher than those in the NVA. It was found that the average $O_3$ increase in the VA during spring might result from the combined effects such as the photochemical production from diverse anthropogenic sources and the $O_3$ accumulation due to geographical features (e.g., the semi-closed topography) and wind conditions (e.g., a low wind speed). In addition, the nocturnal $O_3$ increase in the VA during spring was primarily caused by local wind conditions (e.g., mountain and valley winds) with the low wind speed (approximately $1{\sim}2\;m\;s^{-1}$). On the other hand, the $O_3$ difference between the two areas during summer might be because of the photo-chemical production with the $O_3$ precursors (especially the AVOCs) rather than the contribution of wind conditions.

Fast Structure Recovery and Integration using Improved Scaled Orthographic Factorization (개선된 직교분해기법을 사용한 빠른 구조 복원 및 융합)

  • Park, Jong-Seung;Yoon, Jong-Hyun
    • Journal of Korea Multimedia Society
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    • v.10 no.3
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    • pp.303-315
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    • 2007
  • This paper proposes a 3D structure recovery and registration method that uses four or more common points. For each frame of a given video, a partial structure is recovered using tracked points. The 3D coordinates, camera positions and camera directions are computed at once by our improved scaled orthographic factorization method. The partially recovered point sets are parts of a whole model. A registration of point sets makes the complete shape. The recovered subsets are integrated by transforming each coordinate system of the local point subset into a common basis coordinate system. The process of shape recovery and integration is performed uniformly and linearly without any nonlinear iterative process and without loss of accuracy. The execution time for the integration is significantly reduced relative to the conventional ICP method. Due to the fast recovery and registration framework, our shape recovery scheme is applicable to various interactive video applications. The processing time per frame is under 0.01 seconds in most cases and the integration error is under 0.1mm on average.

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Automatic Defect Detection and Classification Using PCA and QDA in Aircraft Composite Materials (주성분 분석과 이차 판별 분석 기법을 이용한 항공기 복합재료에서의 자동 결함 검출 및 분류)

  • Kim, Young-Bum;Shin, Duk-Ha;Hwang, Seung-Jun;Baek, Joong-Hwan
    • Journal of Advanced Navigation Technology
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    • v.18 no.4
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    • pp.304-311
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    • 2014
  • In this paper, we propose a ultra sound inspection technique for automatic defect detection and classification in aircraft composite materials. Using local maximum values of ultra sound wave, we choose peak values for defect detection. Distance data among peak values are used to construct histogram and to determine surface and back-wall echo from the floor of composite materials. C-scan image is then composed through this method. A threshold value is determined by average and variance of the peak values, and defects are detected by the values. PCA(principal component analysis) and QDA(quadratic discriminant analysis) are carried out to classify the types of defects. In PCA, 512 dimensional data are converted into 30 PCs(Principal Components), which is 99% of total variances. Computational cost and misclassification rate are reduced by limiting the number of PCs. A decision boundary equation is obtained by QDA, and defects are classified by the equation. Experimental result shows that our proposed method is able to detect and classify the defects automatically.

EFFECT OF PROCESSING ON THE NUTRITIVE VALUE OF EIGHT CROP RESIDUES AND TWO FOREST GRASSES IN GOATS AND SHEEP

  • Reddy, M.R.;Reddy, G.V.N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.5 no.2
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    • pp.295-301
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    • 1992
  • Eight crop residues : 1, sorghum (Sorqhum bicolor) straw, 2, maize (Zea mays) straw, 3, cotton (Gossypium Sp.) straw, 4, sunflower (Helianthus Sp.) straw, 5, cotton (Gossypium Sp.) seed hulls, 6, groundnut (Archais hypogaea) hulls, 7, maize (Zea mays) cobs, 8, sugarcane (Saccharum officinarum) bagasse and two forest grasses 9, Heteropogan contortus dry grass and 10, Sehima nervosum dry grass were subjected to three physical processing 1, chopping (2-3 cm) 2, grinding (8 mm sieve) and 3, pelleting (10 mm die holes). The processed material was fed ad lib. Along with 250 g of concentrate mixture per head per day to 6 adult local goats and 16 adult Nellore rams in ten digestion experiments and finally assessed the nutritive value of the processed roughages by difference method. Grinding increased bulk density by 32.4 (cotton seed hulls, CSH) to 88.1% (Sehima dry grass) while pelleting of ground material increased bulk density by 53.9 (maize cobs) to 235.8% (maize straw). The average particle size ranged from $584.1/^U$ (sorghum straw) to $1467/^U$ (CSH). Modulus of uniformity ranged from 2:5:3 (sorghum straw) to 7:2:1 (CSH) while modulus of fineness ranged from 3.4 (sorghum straw) to 5.4 (CSH). Molasses absorbability was highest with cotton seed hulls and least with maize cobs. Pelleting increased DM intake of the residues except cotton seed hulls compared to grinding. Grinding of chopped material/unprocessed material increased DM intake on sorghum straw and cotton seed hulls. Sheep consumed more DM compared to goats on all the residues except sorghum and sunflower straws. Pelleting increased nutritive value of all the residues compared to grinding and chopping. However, no difference was observed in the nutritive value due to grinding and chopping. Goats performed better compared to sheep in utilizing the fibrous residues.

The Effects of Gabapentin in Treatment of Burning Mouth Syndrome: Retrospective Pilot Study

  • Heo, Jun-Young;Ok, Soo-Min;Jeong, Sung-Hee;Kim, Kyung-Hee;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
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    • v.39 no.3
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    • pp.96-99
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    • 2014
  • Purpose: The objective of this retrospective pilot study was to evaluate the effectiveness of Gabapentin in patients with primary burning mouth syndrome (BMS). Methods: Ten subjects were diagnosed with primary BMS (8 women and 2 men). The mean age was 60.1 years. They had clinical examination to exclude local factors such as the presence of Candida species, xerostomia, lichen planus, etc. They also underwent hematological examination to exclude secondary BMS due to systemic disorders. Pain was assessed by patients on an 11-point numerical rating score system (0 to 10). Gabapentin was administered at a starting dose of 300 mg/day, slowly titrated up to maximum of 1,800 mg/day. All patients were treated for 4 weeks. Results: One half of the patients (n=5) obtained reduction in pain over the treatment period. Four patients reported no reduction in pain symptoms. One patient reported that symptoms were worsening. The average pain score before the treatment was 6.3 and after the treatment was 5.25. No significant relationship was detected between pretreatment and posttreatment pain score. Only one patient noted mild side effect (dizziness). Conclusions: This retrospective pilot study provides no preliminary evidence that Gabapentin has effect in the management of BMS. However, further research (well-designed, randomized, and controlled trial with large sample) would be needed to investigate the efficacy of Gabapentin in treatment of BMS.