• Title/Summary/Keyword: construction research

Search Result 15,392, Processing Time 0.044 seconds

Predicting Unsaturated Soil Water Content Using CIELAB Color System-based Soil Color (CIELAB 색 표시계 기반 토색을 활용한 불포화토 함수비 예측 연구)

  • Baek, Sung-Ha;Park, Ka-Hyun;Jeon, Jun-Seo;Kwak, Tae-Young
    • Journal of the Korean Geotechnical Society
    • /
    • v.39 no.2
    • /
    • pp.31-42
    • /
    • 2023
  • A study was conducted to use soil color obtained from digital im ages as an indicator of soil water content. Digital images of Jumoonjin standard sand with five different water contents were captured under nine different lighting conditions. Through digital image processing, the soil color of the sample was obtained based on the CIELAB color system, and the effect of lighting conditions and water content on the soil color was analyzed. The results indicated that L* showed a high correlation with illuminance, whereas a* and b* showed a high correlation with color temperature. As the water content increased, L*, which represents the brightness of the soil color, decreased, and a* and b* increased. Therefore, the soil color changed from green and blue to red and yellow. Based on the regression analysis results of lighting conditions, water content, and soil color, a water content predicting method based on the soil color of silica-based sand photographed under irregular light conditions was proposed. The proposed method can predict the water content with a m axim um error of 0.29%.

The Future of NVH Research - A Challenge by New Powertrains

  • Genuit, Ing. K.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2010.05a
    • /
    • pp.48-48
    • /
    • 2010
  • Sound quality and NVH-issues(Noise, Vibration and Harshness) of vehicles has become very important for car manufacturers. It is interpreted as among the most relevant factors regarding perceived product quality, and is important in gaining market advantage. The general sound quality of vehicles was gradually improved over the years. However, today the development cycles in the automotive industry are constantly reduced to meet the customers' demands and to react quickly to market needs. In addition, new drive and fuel concepts, tightened ecological specifications, increase of vehicle classes and increasing diversification(increasing market for niche vehicles), etc. challenge the acoustic engineers trying to develop a pleasant, adequate, harmonious passenger cabin sound. Another aspect concerns the general pressure for reducing emission and fuel consumption, which lead to vehicle weight reductions through material changes also resulting in new noise and vibration conflicts. Furthermore, in the context of alternative powertrains and engine concepts, the new objective is to detect and implement the vehicle sound, tailored to suit the auditory expectations and needs of the target group. New questions must be answered: What are appropriate sounds for hybrid or electric vehicles? How are new vehicle sounds perceived and judged? How can customer-oriented, client-specific target sounds be determined? Which sounds are needed to fulfil the driving task, and so on? Thus, advanced methods and tools are necessary which cope with the increasing complexity of NVH-problems and conflicts and at the same time which cope with the growing expectations regarding the acoustical comfort. Moreover, it is exceedingly important to have already detailed and reliable information about NVH-issues in early design phases to guarantee high quality standards. This requires the use of sophisticated simulation techniques, which allow for the virtual construction and testing of subsystems and/or the whole car in early development stages. The virtual, testing is very important especially with respect to alternative drive concepts(hybrid cars, electric cars, hydrogen fuel cell cars), where complete new NVH-problems and challenges occur which have to be adequately managed right from the beginning. In this context, it is important to mention that the challenge is that all noise contributions from different sources lead to a harmonious, well-balanced overall sound. The optimization of single sources alone does not automatically result in an ideal overall vehicle sound. The paper highlights modern and innovative NVH measurement technologies as well as presents solutions of recent NVH tasks and challenges. Furthermore, future prospects and developments in the field of automotive acoustics are considered and discussed.

  • PDF

Research Trends of Polybenzimidazole-based Polymer Electrolyte Membranes for High-temperature Polymer Electrolyte Membrane Fuel Cells (고온 구동형 고분자 전해질 막 연료전지용 폴리벤즈이미다졸계 고분자 전해질 막의 개발 동향)

  • HyeonGyeong, Lee;Gabin, Lee;Kihyun, Kim
    • Membrane Journal
    • /
    • v.32 no.6
    • /
    • pp.442-455
    • /
    • 2022
  • High-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) has been studied as an alternative to low-temperature PEMFC due to its fast activation of electrodes and high resistance to electrode poisoning by carbon monoxide. It is highly required to develop stable PEMs operating at high temperatures even doped by ion-conducting materials for the development of high-performance and durable HT-PEMFC systems. A number of studies have been conducted to develop polybenzimidazole (PBI)-based PEMs for applications in HT-PEMFC due to their high interaction with doped ion-conducting materials and outstanding thermomechanical stability under high-temperature operation. This review focused on the development of PBI-based PEMs showing high performance and durability. Firstly, the characteristic behavior of PBI-based PEMs doped with various ion-conducting materials including phosphoric acid was systematically investigated. And then, a comparison of the physicochemical properties of the PEMs according to the different membrane manufacturing processes was conducted. Secondly, the incorporation of porous polytetrafluoroethylene substrate and/or inorganic composites to PBI matrix to improve the membrane performances was studied. Finally, the construction of cross-linked structures into PBI-based PEM systems by polymer blending method was introduced to improve the PEM properties.

A Study on Road Traffic Volume Survey Using Vehicle Specification DB (자동차 제원 DB를 활용한 도로교통량 조사방안 연구)

  • Ji min Kim;Dong seob Oh
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.22 no.2
    • /
    • pp.93-104
    • /
    • 2023
  • Currently, the permanent road traffic volume surveys under Road Act are conducted using a intrusive Automatic Vehicle Classification (AVC) equipments to classify 12 categories of vehicles. However, intrusive AVC equipment inevitably have friction with vehicles, and physical damage to sensors due to cracks in roads, plastic deformation, and road construction decreases the operation rate. As a result, accuracy and reliability in actual operation are deteriorated, and maintenance costs are also increasing. With the recent development of ITS technology, research to replace the intrusive AVC equipment is being conducted. However multiple equipments or self-built DB operations were required to classify 12 categories of vehicles. Therefore, this study attempted to prepare a method for classifying 12 categories of vehicles using vehicle specification information of the Vehicle Management Information System(VMIS), which is collected and managed in accordance with Motor Vehicle Management Act. In the future, it is expected to be used to upgrade and diversify road traffic statistics using vehicle specifications such as the introduction of a road traffic survey system using Automatic Number Plate Recognition(ANPR) and classification of eco-friendly vehicles.

A Study on the Mid- to Long-term Public Library Expansion Plan in Daegu City (대구시 중장기 공공도서관 확충방안 연구)

  • Hee-Yoon Yoon;Seon-Kyung Oh
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.57 no.3
    • /
    • pp.97-117
    • /
    • 2023
  • The purpose of this study is to suggest a mid- to long-term expansion plan to resolve the blind spot and alleviate the imbalance of public library services in Daegu City. The research methods for this purpose included literature review, related laws and statistical data analysis, case study, and opinion survey. As a result, the first service area was set as a total of 14 areas based on administrative districts(Jung-gu, Seo-gu, Nam-gu, and Dalseong-gun each have one, Dong-gu and Buk-gu each have two, and Suseong-gu and Dalseo-gu have three each). Second, the expansion scenario for public libraries in Daegu City was proposed to add 26 libraries by the final target year (2032) based on the trend of national library growth over the past 13 years (2008-2020) and the forecast for the next 10 years (2023-2032). Third, the construction scenarios for each basic local government, excluding the Daegu representative library, are as follows: One library each in Jung-gu, Seo-gu, and Nam-gu; two libraries in Suseong-gu; three libraries in Dalseong-gun; four libraries in Dong-gu; and seven libraries each in Buk-gu and Dalseo-gu. In terms of floor area, it is proposed to add a total of 17 branch libraries with a minimum legal standard of 330-2,499㎡, four central libraries with 2,500-4,999㎡ each, and four central libraries with 5,000-9,999㎡ each. On the premise of these conditions, Daegu City and public libraries should focus on creating an inclusive and open community space, creating a digital platform, strengthening the library operation and cooperation system centered on Daegu representative library, developing collections and specializing services for local hub libraries, enhancing various knowledge information and program services, managing key library indicators and improving social contribution.

Classification of Critically Important Antimicrobials and their Use in Food Safety (중요 항생제의 분류와 식품안전분야에서 활용)

  • Hyo-Sun Kwak;Jun-Hyeok Ham;Eiseul Kim;Yinhua Cai;Sang-Hee Jeong;Hae-Yeong Kim
    • Journal of Food Hygiene and Safety
    • /
    • v.38 no.4
    • /
    • pp.193-201
    • /
    • 2023
  • Antimicrobials in human medicine are classified by The World Health Organization (WHO) into three groups: critically important antimicrobials (CIA), highly important antimicrobials (HIA), and important antimicrobials (IA). CIA are antibiotic classes that satisfy two main criteria: that they are the sole or the only available limited therapeutic option to effectively treat severe bacterial infections in humans (Criterion 1), and infections where bacteria are transmitted to humans from non-human sources or have the potential to acquire resistance genes from non-human sources (Criterion 2). WHO emphasizes the need for cautious and responsible use of the CIA to mitigate risk and safeguard human health. Specific antimicrobials within the CIA with a high priority for management are reclassified as "highest priority critically important antimicrobials (HP-CIA)" and include the 3rd generation of cephalosporins and the next generation of macrolides, quinolones, glycopeptides, and polymyxins. The CIA list is the scientific basis for risk assessment and risk management policies that warrant using antimicrobials to reduce antimicrobial resistance in several countries. In addition, the CIA list ensures food safety in the food industry, including for the popular food chain companies McDonald's and KFC. The continuous update of the CIA list reflects the advancement in research and emerging future challenges. Thus, active and deliberate evaluation of antimicrobial resistance and the construction of a list that reflects the specific circumstances of a country are essential to safeguarding food security.

A Guide for Environmental Impact Assessment for the Installation of Water-friendly Facilities in River Zones (하천구역 내 친수시설물 설치를 위한 환경영향평가 검토 가이드 연구)

  • Kyoung-Ho Kim;Junyeong An;Min-Kyu Ji
    • Clean Technology
    • /
    • v.29 no.3
    • /
    • pp.227-234
    • /
    • 2023
  • Recently, local governments have recognized river zones as leisure spaces and local festival venues, and hence, the pressure for developing these zones has increased significantly. However, given the unique functionalities of river zones and the time and costs associated with maintaining facilities and restoring damaged areas, a development plan must be selected carefully. To preserve river zones and to facilitate nature-friendly space utilization, this study focused on improving environmental impact assessment (EIA), which is an institutional implementation procedure for project plans. This study prepared a draft guide for EIA by providing an overview of the research background and survey outcomes, including the status of laws and regulations on river zones, development plans, and opinions on EIA. The results showed that because strategic EIA of basic river plans is important for district designation of river zones and the scope and direction of space utilization, it is necessary to establish a more meticulous business plan before reviewing and evaluating the mini EIA linked to the future implementation of a plan to derive a reasonable assessment. Additionally, this study provides a draft guide for EIA to evaluate the suitability of water-friendly facility construction plans considering the location characteristics and to reflect the factors that can reduce the environmental impacts during the mini EIA stage. In the future, we expect that the results of this study will serve as a foundation for establishing instructions and guides for the development of nature-friendly and water-friendly facilities in river zones during the establishment of plans.

Seasonal Variation of Airborne Chlorides in Coast by Sea Area and Region, South Korea (해역 및 지역에 따른 해안가 대기중 염분량의 계절적 변동)

  • Jung, Jahe;Lee, Jong-Suk
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.43 no.5
    • /
    • pp.611-619
    • /
    • 2023
  • The first survey of the airborne chlorides along the nationwide coast of South Korea was conducted 18 years ago, and the area index of coastal airborne chlorides and salt attack environmental rating are being utilized in the design, construction, and maintenance of domestic structures. However, due to environmental changessuch as climate change and coastal topography changes, changes of airborne chlorides along the coast are expected to occurregionally and by sea area. Therefore, the second survey has been conducted since 2021. Inthis paper, we analyzed the seasonal variations of airborne chlorides along the coast by region and sea area for one year of the second survey. Additionally, we compared the results withthe survey results of Japan's coastal airborne chlorides, which islocated close to South Korea and has a similar climate, to increase the objectivityofthe analysis. The averageairborne chloridesin the second surveywas highest on the west coast, and the seasonal variation was also the largest on the west coast. Looking at the seasonal variations by sea area, the East Sea had highairborne chloridesinthe summer and autumn,theWestSea inthe autumnandwinter, and the SouthSea in the summer. In addition, compared to the firstsurvey, allsea areasshowed short periods ofsignificantly higher coastalsalinity and clearerseasonal variations.

A Study on Construction of Digital Museum Archiving Regarding Dance Costume (무용공연작품 의상을 위한 디지털 뮤지엄 아카이빙 구축)

  • Jeong, Yu-Jin;Yoo, Ji-Young;Baek, Hyun-Soon
    • Journal of Korea Entertainment Industry Association
    • /
    • v.13 no.1
    • /
    • pp.81-88
    • /
    • 2019
  • This article aims to identify the characters and theme shown in dance costume and utilize them from an educational perspective by constructing digital museum archiving, which can be systematically collected, classified and stored from dance costume. It deals with definition of digital museum archiving as theoretical background and examples of how to create digital museum archiving as research content. The role that archiving plays in digital museum and effectiveness have been demonstrated. Archive is a term used to indicate extensive material and its storage and referred to as an integrative model of display in the computer-generated space. When it comes to producing dance costume as a form of digital museum, the museum is to be made in the computer-generated area of dance costume. The museum shows each division of major, medium and minor classification. The major classification divides genre of dance performance into Korean dance, modern dance and ballet. The middle involves choreographers, costume designers. The minor categorization includes newspaper, interviews, performance pictures, and programs. Digital museum has the value of space utilization, creation, culture, utilization of multiple educational programs, offering of digital museum content, two-way communication, and program development of the new display form.

Surver and Construction in Gabensis village, Papua New Guinea (파푸아뉴기니 가벤시스마을 현황과 전망)

  • Chang, K.J.;Seo, G.S.;Byun, Jae Myun;Park, C.H.;Jeon, U.S.;Elick, G.;Eleo, D.
    • Journal of Practical Agriculture & Fisheries Research
    • /
    • v.13 no.1
    • /
    • pp.173-183
    • /
    • 2011
  • Gabensis village is one of the biggest village In the Wampar Local Level Government area within the Huon Gulf District of Morobe Province with a population of around 3,000. The major staple food is banana which is well complemented by minor staples yam, cassava, Singapore/Chinese taro and sweet potato. Apart from gardening for own consumption, the villagers engage in selling of vegetables, garden staples, cocoa beans, coconuts, timber, chicken, fish and pig meat to supplement their livelihood. Livestock like pigs and chickens are also kept for meat and for commercial purpose. Bettlenut which was once one of the main cash crops has now been overtaken by cocoa due to a disease that had attacked almost the entire bettlenut tree population in the area. Even though the Wau-Bulolo highway cuts through the village and all have access to transport infrastructure, the majority of the population still encounter problems in communication due to poor telecommunication coverage. On average most people earn not more than K50 per week due to constrains in production and marketing among others. Gabensis village has the potential to develop a tourism industry given its natural attraction of Lake Wanam. Beside there is also the natural eel farming and the fish pond at the nearby Potsie village. These natural attractions pose huge tourism potential for the community. As part of government services delivery and development, education and health issues is very much important in the community however there is lack of infrastructural development and poor service delivery especially in the area of health. However, the responsibility is on the community to organize themselves to realize that potential. A well developed agro-ecotourism investments would have positive spillover effects to the community thus contributing towards improving the livelihoods of the many farming families.