• Title/Summary/Keyword: Rolling period

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An Experimental Study on GHG Emissions Reduction and Fuel Economy Improvement of Heavy-Duty Trucks by Using Aerodynamics Device Package (공기저항 저감장치 패키지를 이용한 대형화물차량의 연비개선 및 온실가스 저감효과에 관한 실험적 연구)

  • Park, Seungwon;Dong, Lang;Her, Chulhaeng;Yun, Byoeunggyu;Kim, Daewook
    • Transactions of the Korean Society of Automotive Engineers
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    • v.25 no.2
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    • pp.207-218
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    • 2017
  • Improving fuel consumption, particularly that of commercial vehicles, has become a global concern. The reduction in logistics cost has been a key issue in efforts to improve fuel economy and efficiency of transportation equipment. Typical technologies for reducing reduce fuel usage include air resistance reduction technologies, tire rolling resistance technologies, and idle technologies among others. Air resistance technology is a highly effective method that can be easily applied in a short period. As with air resistance technology, several devices involving side skirt, boat tail and gap fairing have been developed based on an analytical 3-D modeling technique for reducing air resistance attributed to the vehicle configuration. The devices were on a 45 feet tractor-trailer and the emission test was done using PEMS equipment. Fuel economy was evaluated by introducing several devices to reduce outer air resistance. The test was conducted by changing the experimental method of SAE J1321 Joint TMC/SAE Fuel Consumption Test Procedure - Type II test. As a result, air resistance decreased by at least 15 % and fuel economy improved by at least 13 %. This study sought to reduce greenhouse gas and improve fuel economy by applying several devices to a test vehicle to lower air resistance.

Effects of Korea-ASEAN FTA on Export via Gwangyang Port: Application of the Panel Gravity Model and Rolling Regression (한.ASEAN FTA가 광양항 수출에 미치는 영향: 패널중력모형과 전향적 이동회귀의 적용)

  • Park, Honggyun;Kim, Changbeom
    • Journal of Korea Port Economic Association
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    • v.30 no.2
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    • pp.133-143
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    • 2014
  • The paper uses a panel gravity model to analyse the determinants of export via Gwangyang port for the period from 2000-2012. The gravity model includes export via Gwangyang port, GDP and population of trading partners, the distances between Korea and its partners, and Korea-ASEAN FTA dummy. Hausman test shows up which one is exactly appropriate between random effect estimation and fixed effect estimation to use panel dataset. It depends on whether or not existence or nonexistence of the correlation between unobserved omitted factors and variables. Fixed effect estimation is suitable for this paper by the rejection of null hypothesis. An Empirical analysis of this paper shows GDP influences positive effects and distance influences negative effects to Gwangyang port trading partners. In addition, the results strongly supported the effects of Korea-ASEAN FTA on the growth of Gwangyang port export.

Development of Environment Assessment Software for Electronic Multiple Unit (EMU) (전동차 환경성 평가 S/W RACE의 개발)

  • Kim, Yong-Ki;Lee, Jae-Young;Lee, Cheul-Kyu;Eun, Jong-Hwan
    • Journal of the Korean Society for Railway
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    • v.11 no.3
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    • pp.211-215
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    • 2008
  • Generally, an EMU (Electronic Multiple Unit) is manufactured by assembling a large number of components and parts with extensive raw materials. Throughout its entire life cycle, much both the complicated system and long operating period. Therefore, it is necessary to the environmental performance of EMUs from raw materials to waste. In this study, RACE (Rail Assessment for Clean Environment) was developed as the software that can analyze the environmental RACE had several LCI (Life Cycle Inventory) database for main components as well as principal materials in EMUs. In the future, RACE can also be used as a tool for environmental communication between manufacturers and operators. Also, we will improve RACE continuously to assess more easily the environment of rolling stocks EMU for user.

A Survey about Oral Hygiene Management Attitude among People with Hearing Impairments and Speech defect in an Area (일부 지역 청각·언어장애인의 구강위생관리행태에 관한 조사 연구)

  • Lee, Jung-hee;Park, Myung-Suk
    • Journal of dental hygiene science
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    • v.10 no.4
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    • pp.273-278
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    • 2010
  • This study surveyed people with hearing impairments and speech defect living in an area of Gyeonggi-do using a self-administered questionnaire and interviewed them with a deaf interpreter's help during the period from January 21 to February 14, 2009 in order to investigate their oral health management attitude according to their general characteristics. The difference between males and females was statistically significant. The results of this study were as follows. 1. As to the number of times of tooth brushing according to gender, 62.5% of males and 34.2% of females brushed their teeth 2 times, and 25.0% and 35.4% 3 times. 2. As to experiences in scaling according to Academic qualification, those with high academic qualification had scaling more regularly 3. As to tooth brushing methods according to cohabitant, the rolling method was most common regardless of cohabitant. As to the number of times of tooth brushing according to residence type, 41.9% of those living with their parents brushed their teeth 3 times, and 69.2% of those living alone and 47.5% of married ones 2 times. 4. With regard to how to access oral hygiene management education, 81.1% of elementary school graduates used multimedia materials and sign language explanation and captions, 48.6% of middle school graduates used multimedia materials and sign language explanation and 14.3% multimedia materials and captions, 50.0% of high school graduates used multimedia materials and sign language explanation and 17.3% multimedia materials and captions. The parish for the buccal cavity hygiene managements of the hearing impairments speech defect and Development of an educational program are needed.

Management to Prepare Fast Green Suitable for International Golf Tournament in Korea - A Case Study of the Lakeside Country Club - (한국에서 국제 골프 토너먼트 규격에 맞는 빠른 그린 관리 방법 - 레이크사이드 컨트리 클럽을 사례로 -)

  • 장유비;김진관;박장혁;심경구
    • Journal of the Korean Institute of Landscape Architecture
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    • v.31 no.1
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    • pp.66-77
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    • 2003
  • The purpose of this study is to propose a standard putting green management program to prepare fast green suitable for international golf tournaments, and to conform whether the reported green speed model can be applied to the real field situations. The west course of Lakeside Country Club was selected for the case study. This study was initiated on August 1st, 2001 and continued through October 4th, 2001. The results are summarized as follows: 1. Following the long-term schedule, 'penncross' creeping bentgrass turf was mowed at 5.0mm(37days), 4.5mm(8days), 4.0mm(4days), 3.5mm(2days), 3.2mm(2days), 3.0mm(2days), 2.8mm(2days) and the mowing direction was changed daily. Variation of mowing height was reduced to a minimum range. Core aerification with deep tines was applied 19 days prior to the first practice round. Dry sand maintenance was top-dressed 2 times at 1.5mm/$m^2$ on the 17th day and 1.0mm/$m^2$ on the 10th day. Minimum irrigation was applied to keep the turf alive. During the tournament preparation week, dew on the putting greens was removed by using a sponge roller. Following the dew removal, the greens were cut once each morning at a height of 2.8mm. The mower used was the 21 inch working behind mower equipped with a tournament bedknife and 11 reel blades. Following the mowing, the peens were rolled with a light-weight roller in one direction in the morning. Rolling was used as a finishing technique to ensure that the surface was as smooth as possible, and to provide true ball roll and maximum green speed. In conclusion these management practices satisfied the daily green stimpmeter readings required for USGA championship play. 2. During the period of tournament preparation, no damage was observed on the green, but scalping in green edge appeared in about 0.39% of the total area of 18 greens in the west course.

Effects of functional training on strength, function level, and quality of life of persons in intensive care units

  • Seo, Byul;Shin, Won-Seob
    • Physical Therapy Rehabilitation Science
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    • v.8 no.3
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    • pp.134-140
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    • 2019
  • Objective: The purpose of this study was to investigate the effect of exercise therapy and bedside ergometer exercise on muscle strength, function level, and quality of life of persons in intensive care. Design: Randomized Controlled Trial Methods: Sixteen patients in the ICU were randomly assigned to either the exercise group (n=8) or the bedside cycle ergometer group (n=8). Activities in the ICU exercise group (rolling, sitting at the edge of the bed, transfer from sitting to standing, standing balance training, ambulation) and bedside cycle ergometer group were performed 5 times a week for 30 minutes during the ICU admission period. Medical Research Council (MRC) and Functional Status Scale-Intensive Care Unit (FSS-ICU) parameters were assessed at the time of admission to the ICU, and reevaluation was assessed on the day of ICU discharge. The Short Form-36 (SF-36) was assessed at the time of discharge from the ICU. Results: MRC and FSS-ICU were significantly increased before and after intervention in both the experimental and control groups (p<0.05). There was a significant difference between MRC and FSS-ICU in the comparison of the changes before and after the intervention (p<0.05). SF-36 was compared between groups after intervention and there was a significant difference between the experimental and the control group (p<0.05). Conclusions: Muscle strength and functional levels improved after intervention in both the experimental and control groups. The ICU exercise group was more effective than the bedside cycle ergometer group to improve muscle strength, functional level, and quality of life performance of persons in the ICU.

Status of Industrial Environments of Some Industries in Taegu Kyungpook Area (대구지방 산업장에 있어서 건강장애요인과 작업환경검사에 대한 기업인의 수용태도 (ll))

  • Kim, Du-Hui;Seong, Su-Won
    • 월간산업보건
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    • s.8
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    • pp.4-30
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    • 1988
  • Examination of working environments was conducted to get more detailed data about harmful working environments and to make a contribution to more effective management. Study was carried out on 722 factories located in Taegu city and eight counties in Kyungpook Province, Korea, for a period of one year, from February 1 to December 30, 1986. The total number and proportion of workers exposed to harmful material was 37,697, 45.2% among 83,368 workers. The results according to exposed material were as follows: 1. In the case of noise, proportion of exceeding the 8-hour TLV was 59%, Included were nail-cutting in assembly metal manufacturing industry and weaving process in textile. 2. Dust in mill process of coal manufacturing industries exceeded the TLV of second class of dust at all parts and exceeded the TLV at 6% as a whole.: 3. The fields of industry lower than 70 lux of illumination were storage equipment of food, auto-winder of textile, painting of wood wares and coal mixing, and 44% of all cases was lower than standard. 4. As a result of temperature index investigation(WBGT), about 12% of all sujects exceeded limit value. Included parts were rolling machine and reducing room. 5. In the case of organic solvents, TLV was exceeded at about 8%, The parts exceeded TLV according to materials belonged to this category were as follows. 1) Toluene: adhesive work in assembly metal manufacturing 2) Xylene: printing and paint mixing in chemical manufacturing 3) Methyl ethytl ketone: paint mixing in all parts examined and coating machine partially in chemical manufacturing 4) Methyl isobutyl ketone: printing in chemical manufacturing 5) Acetone: vapor polishing in assembly metal manufacturing 6. Among specified chemical materials, the concentration of HC1 in the air in metal assembly manufacturing factory exceeded TLV. in one of three assembly metal manufacturing examined. Others, such as benzene, acetic acid, formic acid, sodium hydroxide, formalin, ammonia, copper, chromate etc. were lower than TLV in its indoor atmospheric concentration. As a whole, the proportion of exceeding TLV was about 0.8% 7. The concentrations of inorganic lead were lower than TLV in all parts examined. The results of this investigation show the fact that current management of working environments is not satisfactory, and so more active management is needed.

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Study on Development of Export Packaging for Fresh Melon (신선 멜론의 수출포장개발에 관한 연구)

  • Lee, Myung-Hoon;Jung, Jun-Jae
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.15 no.3
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    • pp.83-91
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    • 2009
  • It is very difficult to export the fresh agricultural products to long distance countries such as USA and EU without any damage. Fresh products exporting would overcome very severe conditions such as hot and cold weather changes, heavy vibrations with rolling and pitching during the target distribution period, therefore, the packaging needs the immobility of products in the container and the keeping its quality by packaging materials or methods under any surrounding environments, especially. The physical strength of outer box should be designated according to its own characteristics for agricultural product packaging. Packaging dimension which would be fit to standard pallet is also very important factor to reduce the distribution cost. There have been many agricultural products researches for export packaging to the USA so far. However they have never got desirable results which enough to apply it in real. The main purpose of this research is to develop optimum compressive strength and optimum dimension of corrugated fiberboard box which would be used to USA export packaging of fresh melon as well as Japan.

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A study on the environmental conditions of barley and wheat sterilization - In preference to term of location and soil moisture - (맥류(麥類) 불임발생(不稔發生)의 환경요인(環境要因)에 관한 연구 - 입지조건(立地條件) 및 토양수분(土壤水分)을 중심(中心)으로 -)

  • Park, Kyeong-Bae;Jung, Yeun-Tae;No, Yeong-Pal;Park, Rae-Kyeong
    • Korean Journal of Soil Science and Fertilizer
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    • v.12 no.1
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    • pp.25-34
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    • 1979
  • To clealify the cause of barley and wheat sterility that occurred 77 / 78 cultivation period in Yeongnam area, a few environmental conditions were analyzed. The results are summarized as follows; 1. During the important growing stages such as meiosis and heading stages of barley encountered with severe droughtiness and unusual low temperature. 2. Soil moisture contents in the double cropping paddy soils were higher than cultivated uplands, and in the subsoils than the surface soils, in the clay soils than the sandy soils, in the northern aspect than the southern aspect of slope, respectively. 3. The sterilizing percentage of barley in the double cropping paddy fields were lower than cultivated uplands, in the alluvial fans and plains were lower than cultivated uplands, in the alluvial fans and plains were lower than in rolling or in foot slopes and the northerm aspect of slopes were lower than southern aspect. 4. The sterilizing percentage in the sandy soils were higher than clay soils and in the soils that have shallower plowing layer and shallower available depth had higher sterility. 5. The sterilizing percentage of barley had negative correlation with soil moisture contents in the surface and subsoils in both of cultivated upland or double cropping paddy fields. 6. The droughtiness that prevailed over reproductive growing stages of barley might be cause the sterility and the severe coldness also could be accelerate the phenomenon.

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Effect of Educational Attainment of Household Head on Eating-out Demand (가구주 학력이 외식수요에 미치는 효과)

  • Kim, Young-Sook;Chun, Soon-Sil
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.9
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    • pp.1407-1413
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    • 2005
  • Korean households' expenditures on the eating -out have been steadily increasing except for the foreign exchange crisis period. This paper aimed to examine the eating-out expenditures of salary and wage earners's households by educational attainment of household head. We modeled the demand function of eating-out in terms of income and price, examining the responsiveness of eating-out demand to changes in income and price using econometric methods such as regression, rolling regression and impulse response. This paper showed that coefficients of income and price tended to decrease as the income rises in the long-run. Specifically, the higher the educational attainment of household head is, the smaller the coefficients of income and price we. The impulse response analysis also indicated that while price shocks decreased the demand for eating-out, income shocks tended to increase tile demand for eating-out in all the educational attainments. Furthermore income shocks were much greater and last longer than price shocks at all educational attainments of household heads.