• Title/Summary/Keyword: 3-manifold

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Information Management System for Construction Works using Web GIS (Web GIS를 이용한 건설공사 정보관리 시스템 구축)

  • Woo, Je-Yoon;Koo, Jee-Hee;Na, Joon-Yeep;Pyeon, Mu-Wook
    • Journal of Korea Spatial Information System Society
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    • v.3 no.2 s.6
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    • pp.45-51
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    • 2001
  • It is difficult for existing construction support system to provide real-world information such as geographical and spatial data, geographic information system is expected to be able to supply efficiently analyzing and supporting function as well as actual data by connecting construction support system. Furthermore, the providing method and content of GIS are varied by building various network and information service, and use of web GIS which can offer diverse and dynamic solution on network is spreaded. In this study, information management system for construction works(CIMSGIS : Construction Information Management System on Web GIS) based on web GIS is developed, which can confirm instantly state of advance and manage construction progress by real-time reporting and instruction. Also CIMSGIS can support decision making on intuitive understanding and manifold operation reporting.

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The Effect of In-Outlet Differential Pressure on a Valve Body Stress and Deformation by the Blow-by Gas Flow Characteristic in the PCV valve for Automobile (자동차용 PCV밸브내 유통특성에 의한 밸브응력 및 변형에 미치는 입출구 차압의 영향)

  • Kwon Oh-Heon;Lee Yeon-Won;Song Sang-Min;Lee Jong-Hoon;Kang Ji-Woong
    • Journal of the Korean Society of Safety
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    • v.20 no.1 s.69
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    • pp.36-41
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    • 2005
  • PCV(Positive Crankcase Ventilation) valve acts as a flow control valve to get a re-combustion of blow-by gas by having it flow from a crankcase to an inlet manifold suction tube. The blow-by gas of the crankcase should be eliminated or taken properly because it cause corrosion to critical parts, and contributes to increase crankcase pressure that can cause a drop in efficiency. The excessive stress and strain on the PCV valve that remove these harmful gas would be bring the difficult on the flow rate control and failure of the valve. Those condition inevitably induce the accident. Therefore, this study purpose is FEM evaluation of the stresses and deformation in the X3 PCV model according to the change of the differential pressure between inlet and outlet. From results, the maximum equivalent stresses increased linearly according to the increase of the differential pressure at the about 50mm from the inlet position and were under the yield strength of the valve. And the deformations were relatively small regardless of the in-outlet differential pressure variation.

A Study on the Characteristic and Droplet Uniformity of Spray Injection to Exhaust Gas Flow from Urea Solution Injector (Urea 수용액의 배기가스 유동장내 분무 특성과 분무 균일도에 관한 연구)

  • Oh, Jung-Mo;Cha, Won-Sim;Kim, Ki-Bum;Lee, Jin-Ha;Lee, Ki-Hyung
    • Transactions of the Korean Society of Automotive Engineers
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    • v.19 no.3
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    • pp.83-89
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    • 2011
  • Diesel engines can produce higher fuel efficiency and lower $CO_2$ emission, they are subject to ever more stringent emission regulation. However, there are two major emission concerns fo diesel engines like such as particulate matter (PM) and nitrogen oxides (NOx). Moreover, it is not easy to satisfy the regulations on the emission of NOx and PM, which are getting more strengthened. One of the solutions is to apply the new combustion concept using multistage injection such as HCCI and PCCI. The other solution is to apply after-treatment systems. For example, lean NOx trap catalyst, Urea-SCR and others have various advantages and disadvantages Especially, Urea-SCR system have advantages such as a high conversion efficiency and a wide operation conditions. Hence the key factor to implementation of Urea-SCR technology, good mixing of urea(Ammonia) and gas, reducing Ammonia slip. Urea mixer components are required to facilitate evaporation and mixing because the liquid state of urea poses significant barriers for evaporation, and the distance to mixer is the most critical that affect mixer performance. In this study, to find out the distance from injector to mixer and simulation factor, a laser diagnostics and high speed camera are used to analyze urea injector spray characteristics and to present a distribution of urea solution in transparent manifold In addition, Droplet Uniformity Index is calculated from the acquired images by using image processing method to clarify the distribution of spray.

Determination of Selenium in Milk by ICP-OES (ICP-OES를 이용한 우유의 Selenium 분석)

  • 김효중;박종길;신정걸;백영진
    • Food Science of Animal Resources
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    • v.23 no.4
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    • pp.356-360
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    • 2003
  • The purpose of this paper was to determine the quantity of selenium in milk by inductively coupled plasma optical emission spectrometry. The sample was digested in teflon vessel containing nitric-hydrogen peroxide acid mixture. After digestion, the sample is treated with additional hydrochloric acid. Total selenium was reduced with sodium borohydride and concentrated hydrochloric acid in a simplified hydride generation(HG) manifold. The optimum conditions of HG are 2 M for HCl, 1.5% for NaBH$_4$, 1.2 mL/mim for sample flow. Recovery rates by the standard addition method were 88.0% at 10 ppb and 92.2% at 10 ppm. The relative standard deviations were 4.8 and 3.2%, respectively. This method showed a good accuracy and precision. And so it was highly suitable for determination of small quantity of selenium in milk.

Combustion Characteristics of Ammonia-Gasoline Dual-Fuel System in a One liter Engine (1리터급 엔진을 이용한 암모니아-가솔린 혼소 성능 특성)

  • Jang, Jinyoung;Woo, Youngmin;Yoon, Hyung Chul;Kim, Jong-Nam;Lee, Youngjae;Kim, Jeonghwan
    • Journal of the Korean Institute of Gas
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    • v.19 no.6
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    • pp.1-7
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    • 2015
  • An ammonia fuel system is developed and applied to a 1 liter gasoline engine to use ammonia as primary fuel. Ammonia is injected separately into the intake manifold in liquid phase while gasoline is also injected as secondary fuel. As ammonia burns 1/6 time slower than gasoline, the spark ignition is needed to be advanced to have better combustion phasing. The test engine showed quite high variation in the power output to lead high increase in THC emission with large amount of ammonia, that is, higher than 0.7 ammonia-gasoline fuel ratios.

Nitrous oxide splurge in a tertiary health care center and its environmental impact: No more laughing stock

  • Amit Sharma;GD Puri;Rajeev Chauhan;Ankur Luthra;Gauri Khurana;Amarjyoti Hazarika;Shyam Charan Meena
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.24 no.1
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    • pp.67-73
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    • 2024
  • Background: Nitrous oxide has been an integral part of surgical anesthesia for many years in the developed world and is still used in developing countries such as India. The other main concerns in low-resource countries are the lack of an advanced anesthesia gas-scavenging system and modular surgical theatres. As a greenhouse gas that has been present in the atmosphere for more than 100 years and damages the ozone layer, nitrous oxide is three times worse than sevoflurane. Here, we conducted an observational study to quantify the annual nitrous oxide consumption and its environmental impact in terms of carbon dioxide equivalence in one of busiest tertiary health care and research centers in Northern India. Methods: Data related to nitrous oxide expenditure' from the operation theatre and manifold complex of our tertiary care hospital and research center from 2018 to 2021 were collected monthly and analyzed. The outcomes were extracted from our observational study, which was approved by our institutional ethics board (INT/IEC/2017/1372 Dated 25.11.2017) and registered prospectively under the Central Registry (CTRI/2018/07/014745 Dated 05.07.2018). Results: The annual nitrous oxide consumption in our tertiary care hospital was 22,081.00, 22,904.00, 17,456.00, and 18,392.00 m3 (cubic meters) in 2018, 2019, 2020, and 2021, respectively. This indicates that the environmental impact of nitrous oxide (in terms of CO2 equivalents) from our hospital in 2018, 2019, 2020, and 2021 was 13,016.64, 13,287.82, 10,289.94, and 10,841.24 tons, respectively. Conclusion: This huge amount of nitrous oxide splurge is no longer a matter of laughter, and serious efforts should be made at every central and peripheral health center level to reduce it.

Effect of Fingertip Temperature on Multi-finger Actions in Young Adults (손 끝 온도변화가 젊은 성인의 다중 손가락 동작에 미치는 효과)

  • Shin, Narae;Xu, Dayuan;Song, Jun Kyung;Park, Jaebum
    • Korean Journal of Applied Biomechanics
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    • v.29 no.3
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    • pp.157-166
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    • 2019
  • Objective: This study examined the effects of stimulating fingertip temperature on the patterns of force sharing and stability properties during multi-finger force production tasks. Method: 9 adult subjects (male: 3, female: 6, age: $26.11{\pm}4.01yrs$, height: $169.22{\pm}5.97cm$, weight: $61.44{\pm}11.27kg$) participated in this study. The experiment consisted of three blocks: 1) maximal voluntary contraction (MVC) task, 2) single-finger ramp task to quantify enslaving (i.e., unintended force production by non-task fingers), and 3) 12 trials of multi-finger steady-state force production task at 20% MVC. There were three temperature conditions including body-temperature (i.e., control condition), $40^{\circ}C$, and $43^{\circ}C$, and the stimulation was given to the index finger only for all experimental conditions. Results: There were no significant differences in the MVC forces, enslaving, and the accuracy of performance during the steady-state task between the conditions. However, the share of stimulated index finger force increased with the index fingertip temperature, while the share of middle finger force decreased. Also, the coefficient of variation of both index and middle finger forces over repetitive trials increased with the index fingertip temperature. Under the framework of the uncontrolled manifold (UCM) hypothesis used to quantify indices of multi-finger synergies (i.e., stability property) stabilizing total force during the steady-state task, the two variance components within the UCM analysis increased together with the fingertip temperature, while no changes in the synergy indices between the conditions. Conclusion: The current results showed that fingertip temperature stimulation only to index finger does not affect to muscle force production capability of multi-finger, independence of individual fingers, and force production accuracy by the involvement of all four fingers. The effect of fingertip temperature on the sharing pattern and force variation may be due to diffuse reflex effects of the induced afferent activity on alpha-motoneuronal pools. However, the unchanged stability properties may be the reflection of the active error compensation strategies by non-stimulated finger actions.

Microstructures and Hardness of Al-Si Coated 11%Cr Ferritic Stainless Steel, 409L GTA Welds (Al-Si 용융도금된 11%Cr 페라이트 스테인리스강, STS409L GTA 용접부의 미세조직과 경도)

  • Park, Tae-Jun;Kong, Jong-Pan;Na, Hye-Sung;Kang, Chung-Yun;Uhm, Sang-Ho;Kim, Jeong-Kil;Woo, In-Su;Lee, Jong-Sub
    • Journal of Welding and Joining
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    • v.28 no.3
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    • pp.92-98
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    • 2010
  • Ferritic stainless steels, which have relatively small thermal expansion coefficient and excellent corrosion resistance, are increasingly being used in vehicle manufacturing, in order to increase the lifetime of exhaust manifold parts. But, there are limits on use because of the problem related to cosmetic resistance, corrosions of condensation and high temperature salt etc. So, Aluminum-coated stainless steel instead of ferritic stainless steel are utilized in these parts due to the improved properties. In this investigation, Al-8wt% Si alloy coated 409L ferritic stainless steel was used as the base metal during Gas Tungsten Arc(GTA) welding. The effects of coated layer on the microstructure and hardness were investigated. Full penetration was obtained, when the welding current was higher than 90A and the welding speed was lower than 0.52m/min. Grain size was the largest in fusion zone and decreased from near HAZ to base metal. As welding speed increased, grain size of fusion zone decreased, and there was no big change in HAZ. Hardness had a peak value in the fusion zone and decreased from the bond line to the base metal. The highest hardness in the fusion zone resulted from the fine re-precipitation of the coarse TiN and Ti(C, N) existed in the base metal during melting and solidification process and the presence of fine $Al_2O_3$ and $SiO_2$ formed by the migration of the elements, Al and Si, from the melted coating layer into the fusion zone.

Reservoir Modeling for Carbon Dioxide Sequestration and Enhanced Oil Recovery (이산화탄소 지중저장과 원유 회수증진 공정을 위한 저류층 모델링)

  • Kim, Seung-Hyok;Lee, Jong-Min;Yoon, En-Sup
    • Journal of the Korean Institute of Gas
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    • v.16 no.3
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    • pp.35-41
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    • 2012
  • Manifold researches for carbon capture and storage (CCS) have been developed and large scale-carbon capture system can be performed recently. Hence, the technologies for $CO_2$ sequestration or storage become necessary to handle the captured $CO_2$. Among them, enhanced oil recovery using $CO_2$ can be a solution since it guarantees both oil recovery and $CO_2$ sequestration. In this study, the miscible flow of oil and $CO_2$ in porous media is modeled to analyze the effect of enhanced oil recovery and $CO_2$ sequestration. Based on Darcy-Muskat law, the equation is modified to consider miscibility of oil and $CO_2$ and the change of viscosity. Finite volume method is used for numerical modeling. As results, the pressure and oil saturation changes with time can be predicted when oil, water, and $CO_2$ are injected, respectively, and $CO_2$ injection is more efficient than water injection for oil recovery.

The Effects of Compensation and Pay Dispersion on Organizational Productivity and Performance: The Case of Korean Professional Basketball Teams (한국프로농구 기업의 임금수준과 임금격차가 구성원의 생산성과 조직성과에 미치는 영향: 한국프로농구를 중심으로)

  • PHILSOO KIM;TAE SUNG JEONG;SANG HYUN LEE
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.2
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    • pp.127-139
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    • 2023
  • Compensation and pay dispersion has been rigorously scrutinized to investigate their impacts on productivity and organizational performance. However, it is difficult to find a systematic study on the systematic dynamics of compensation and pay dispersion effects specifically in the context of Korean venture companies. Venture companies should manage their organizational resources efficiently to maximize their organizational performance through pay structure by efficiently managing the inherent resources. However, we acknowledge that empirical studies on how compensation and pay dispersion affect organizational productivity and performance are rare to find in the Korean context. To overcome this supplement limitation, this study hypothesized that (1) pay and members' productivity are positively related, (2) pay dispersion and organizational productivity have U shaped relationship, and (3) organizational productivity mediates the positive relationship between compensation and organizational performance. Venture companies and professional sports teams share manifold common characteristics such as size, financial circumstances, and operational objectives. We collect 9 seasons (2013~2014 - 2021~2022) of 10 teams' data of Korean Basketball League teams to test our hypotheses. Methodologically, the assessment of our analysis is rendered with PROCESS macro model 58. The statistical results showed that all hypotheses are statistically supported. This study explains how compensation and pay dispersion affect organizational productivity and performance of venture companies in Korea.

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