• Title/Summary/Keyword: Direct evolution

Search Result 221, Processing Time 0.024 seconds

A feasibility study of audio-video communication application using mobile telecommunication in inter-hospital transfer situations (병원 간 전원 상황에서 이동통신망을 이용한 음성화상정보통신 애플리케이션의 유용성에 관한 연구)

  • Jeong, Joo;Kim, Tae-Han;Kang, Saee-Byel
    • The Korean Journal of Emergency Medical Services
    • /
    • v.23 no.1
    • /
    • pp.125-134
    • /
    • 2019
  • Purpose: The aim of this study was to evaluate the usefulness of video communication with medical staff located at a remote location, through a communication application connected to a long term evolution (LTE) mobile communication network in a moving ambulance. Methods: In this study, we recruited patients who were transferred by mobile intensive care unit ambulance from one hospital to another. In the moving ambulance, the information of the patient was transferred to a physician using the application in real time. Recorded video files were evaluated by emergency physicians with experience in video direct medical control. Results: A total of 18 patients were evaluated, and the average score was 5.9 out of a possible 9. It was expected that applying the use of the technology to actual clinical sites would enable the sites to provide assistance. Conclusion: In this study, we confirmed the possibility of benefiting from the clinical field when using the video-audio communication application which is connected to the remote location in real time through the current LTE mobile communication network in the ambulance.

The impact of ram pressure on the multi-phase ism probed by the TIGRESS simulation

  • Choi, Woorak;Kim, Chang-Goo;Chung, Aeree
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.43 no.2
    • /
    • pp.33.1-33.1
    • /
    • 2018
  • Ram pressure stripping by intracluster medium (ICM) can play a crucial role in galaxy evolution in the high-density environment as seen by many examples of cluster galaxies. Although much progress has been made by direct numerical simulations of galaxies (or a galaxy) as a whole in a cluster environment, the interstellar medium (ISM) in galactic disks is not well resolved to understand responses of the ISM in details. In order to overcome this, we utilize the TIGRESS simulation suite that focuses on a local region of galactic disks and resolves key physical processes in the ISM with uniformly high resolution. In this talk, we present the results from the solar neighborhood TIGRESS model facing the ICM winds with a range of ram pressures. When ram pressure is weaker than and comparable to the ISM weight, the ICM winds simply reshape the ISM to the one-sided disk, but star formation rates remain unchanged. Although there exist low-density channels in the multiphase ISM that allow the ICM winds to penetrate through, the ISM turbulence quickly closes the channels and prevents efficient stripping. When ram pressure is stronger than the ISM weight, a significant amount of the ISM can be stripped away rapidly, and star formation is quickly quenched. While the low-density gas is stripped rapidly, star formation still occurs in the extraplanar dense ISM (1-2kpc away from the stellar disk). Finally, we quantify the momentum transfer from the ICM to the ISM using the mass-and momentum-weighted velocity distribution functions of each gas phase.

  • PDF

Discrepancies between Mitochondrial DNA and AFLP Genetic Variation among Lineages of Sea Slaters Ligia in the East Asian Region

  • Kang, Seunghyun;Jung, Jongwoo
    • Animal Systematics, Evolution and Diversity
    • /
    • v.36 no.4
    • /
    • pp.347-353
    • /
    • 2020
  • Although sea slaters Ligia have a significant role in rocky shore habitats, their taxonomic entities have not been clearly understood. In this study, we investigated whether genetic variation inferred from a nuclear genetic marker, namely amplified fragment length polymorphism (AFLP), would conform to that of a mitochondrial DNA marker. Using both the mitochondrial DNA marker and the AFLP marker amplified by the six selective primer sets, we analyzed 95 Ligia individuals from eight locations from East Asia. The direct sequencing of mitochondrial 16S rRNA gene revealed three distinct genetic lineages, with 9.8-11.7 Kimura 2-parameter genetic distance. However, the results of AFLP genotyping analysis with 691 loci did not support those of mitochondrial DNA, and revealed an unexpectedly high proportion of shared polymorphisms among lineages. The inconsistency between the two different genetic markers may be explained by difference in DNA evolutionary history, for example inheritance patterns, effective population size, and mutation rate. The other factor is a possible genomic island of speciation, in that most of the genomic parts are shared among lineages, and only a few genomic regions have diverged.

The Impact of Technology Transfer on Economic Development in the 4.0 Era: Empirical Evidence from the Agriculture and Rural Sector in Vietnam

  • TRAN, Quang Bach;NGUYEN, Thi Yen
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.9 no.5
    • /
    • pp.261-272
    • /
    • 2022
  • Agriculture and the rural sector play a crucial part in Vietnam's socio-economic growth. The study's goal is to see how technology transfer from young intellectual research activities affects the economic evolution of Vietnam's agriculture and rural sector in the 4.0 technology era. The research has used a quantitative method through analysis of linear structural model SEM, with a survey scale including 480 samples that are managers in departments and branches in agriculture and rural sector in the provinces in Vietnam. Research results show that technology transfer from research activities of the young intellectual has a direct and positive impact on economic development in agriculture and rural sector. This level of impact will increase with the participation of the intermediary factors such as awareness of managers, trust, and mechanisms in the mobilization and use of resources. These results contribute to both theoretical and practical aspects when proving the impact of technology transfer from the research activity of the young intellectual to the economic development in the field of agriculture and rural sector in the 4.0 era and the mediating role of awareness of managers, trust and mechanisms in the mobilization and use of resources.

Fabrication of Metal-biochar Composite through CO2 Assisted Co-pyrolysis of Chlorella and Red Mud and Its Application for Persulfate Activation (녹조류와 적니의 이산화탄소환경 공동열분해를 통한 탄소-철 복합체 생성 및 과황산염 활성화를 통한 수중 염료 제거)

  • Jang, Hee-Jin;Kwon, Gihoon;Yoon, Kwangsuk;Song, Hocheol
    • Journal of Soil and Groundwater Environment
    • /
    • v.27 no.1
    • /
    • pp.31-38
    • /
    • 2022
  • The common algae and industrial waste, chlorella and red mud, were co-pyrolyzed in carbon dioxide condition to fabricate iron-biochar composite. In order to investigate the direct effect of chlorella and red mud in the syngas generation and the property of biochar, experiments were performed using mixture samples of chlorella and red mud. The evolution of flammable gasses (H2, CH4, CO) was monitored during pyrolysis. The produced biochar composite was employed as a catalyst for persulfate activation for methylene blue removal. BET analysis indicated that the iron-biochar composite mainly possessed meso- and macropores. The XRD analysis revealed that hematite (Fe2O3) contained in red mud was transformed to Fe3O4 during co-pyrolysis. The composite effectively activated persulfate and removed methylene blue. Among the composite samples, the composite fabricated from the mixture composed of 1:2 chlorella:red mud showed the best performance in syngas generation and methylene blue removal.

Comparative Study of Undoped and Nickel-Doped Molybdenum Oxide Photoanodes for PEC Water Splitting

  • Garcia-Garcia, Matias
    • Journal of Electrochemical Science and Technology
    • /
    • v.13 no.3
    • /
    • pp.377-389
    • /
    • 2022
  • The current global energy supply depends heavily on fossil fuels. This makes technology such as direct water splitting from harvesting solar energy in photoelectrochemical (PEC) systems potentially attractive due to its a promising route for environmentally benign hydrogen production. In this study, undoped and nickel-doped molybdenum oxide photoanodes (called photoanodes S1 and S2 respectively) were synthesized through electrodeposition by applying -1.377 V vs Ag/AgCl (3 M KCl) for 3 hours on an FTO-coated glass substrate immersed in molibdatecitrate aqueous solutions at pH 9. Scanning electron microscopy (SEM), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS) were used for microstructural and compositional characterizations of the photoanodes. In addition, the optical and photoelectrochemical characterizations of these photoanodes were performed by UV-Visible spectroscopy, and linear scanning voltammetry (LSV) respectively. The results showed that all the photoanodes produced exhibit conductivity and catalytic properties that make them attractive for water splitting application in a photoelectrochemical cell. In this context, the photoanode S2 exhibited better photocatalytic activity than the photoanode S1. In addition, photoanode S2 had the lowest optical band-gap energy value (2.58 eV), which would allow better utilization of the solar spectrum.

The Optimization of Sizing and Topology Design for Drilling Machine by Genetic Algorithms (유전자 알고리즘에 의한 드릴싱 머신의 설계 최적화 연구)

  • Baek, Woon-Tae;Seong, Hwal-Gyeong
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.14 no.12
    • /
    • pp.24-29
    • /
    • 1997
  • Recently, Genetic Algorithm(GA), which is a stochastic direct search strategy that mimics the process of genetic evolution, is widely adapted into a search procedure for structural optimization. Contrast to traditional optimal design techniques which use design sensitivity analysis results, GA is very simple in their algorithms and there is no need of continuity of functions(or functionals) any more in GA. So, they can be easily applicable to wide area of design optimization problems. Also, owing to multi-point search procedure, they have higher porbability of convergence to global optimum compared to traditional techniques which take one-point search method. The methods consist of three genetics opera- tions named selection, crossover and mutation. In this study, a method of finding the omtimum size and topology of drilling machine is proposed by using the GA, For rapid converge to optimum, elitist survival model,roulette wheel selection with limited candidates, and multi-point shuffle cross-over method are adapted. And pseudo object function, which is the combined form of object function and penalty function, is used to include constraints into fitness function. GA shows good results of weight reducing effect and convergency in optimal design of drilling machine.

  • PDF

Synthesis of CoO/Co(OH)2 Nanosheets Depending on Reaction Temperatures (반응 온도에 따른 CoO/Co(OH)2 나노시트의 합성)

  • Minjeong Lee;Gayoung Yoon;Gyeong Hee Ryu
    • Korean Journal of Materials Research
    • /
    • v.33 no.5
    • /
    • pp.222-228
    • /
    • 2023
  • Transition metal oxides formed by a single or heterogeneous combination of transition metal ions and oxygen ions have various types of crystal structures, which can be classified as layered structures and non-layered structures. With non-layered structures, it is difficult to realize a two-dimensional structure using conventional synthesis methods. In this study, we report the synthesis of cobalt oxide into wafer-scale nanosheets using a surfactant-assisted method. A monolayer of ionized surfactant at the water-air interface acts as a flexible template for direct cobalt oxide crystallization below. The nanosheets synthesized on the water surface can be easily transferred to an arbitrary substrate. In addition, the synthesizing morphological and crystal structures of the nanosheets were analyzed according to the reaction temperatures. The electrochemical properties of the synthesized nanosheets were also measured at each temperature. The nanosheets synthesized at 70 ℃ exhibited higher catalytic properties for the oxygen evolution reaction than those synthesized at other temperatures. This work suggests the possibility of changing material performance by adjusting synthesis temperature when synthesizing 2D nanomaterials using a wide range of functional oxides, resulting in improved physical properties.

Cosmological Origin of Satellites around Isolated Dwarf Galaxies

  • Chun, Kyungwon;Shin, Jihye;Smith, Rory;Kim, Sungsoo S.
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.44 no.2
    • /
    • pp.39.1-39.1
    • /
    • 2019
  • We trace the cosmological origin of satellites around isolated dwarf galaxies using a very high resolution (12 pc/h) cosmological hydrodynamic zoom simulation. To realistically describe the formation and evolution of small-mass stellar satellites, our model includes a full baryonic physics treatment. We find that the mini-halos form objects resembling dwarf galaxies. The majority of their star forming gas is accreted after reionization, thus the survival of a mini-halo's gas to reionization is not an important factor. Instead, the key factor seems to be the ability for a mini-halo to cool its recently accreted gas, which is more efficient in more massive halos. Although the host galaxy is only a dwarf galaxy itself, we find that ram pressure is an efficient means by which accreted mini-halos lose their gas content, both by interacting with hot halo gas but also in direct collisions with the gas disk of the host. The satellites are also disrupted by the tidal forces near the center of the host galaxy. Compared to the disrupted satellites, surviving satellites are relatively more massive, but tend to infall later into the host galaxy, thus reducing the time they are subjected to destructive environmental mechanisms and dynamical friction.

  • PDF

Microstructural evolution of tantalum nitride thin films synthesized by inductively coupled plasma sputtering

  • Sung-Il Baik;Young-Woon Kim
    • Applied Microscopy
    • /
    • v.50
    • /
    • pp.7.1-7.10
    • /
    • 2020
  • Tantalum nitride (TaNx) thin films were grown utilizing an inductively coupled plasma (ICP) assisted direct current (DC) sputtering, and 20-100% improved microhardness values were obtained. The detailed microstructural changes of the TaNx films were characterized utilizing transmission electron microscopy (TEM), as a function of nitrogen gas fraction and ICP power. As nitrogen gas fraction increases from 0.05 to 0.15, the TaNx phase evolves from body-centered-cubic (b.c.c.) TaN0.1, to face-centered-cubic (f.c.c.) δ-TaN, to hexagonal-close-packing (h.c.p.) ε-TaN phase. By increasing ICP power from 100 W to 400 W, the f.c.c. δ- TaN phase becomes the main phase in all nitrogen fractions investigated. The higher ICP power enhances the mobility of Ta and N ions, which stabilizes the δ-TaN phase like a high-temperature regime and removes the micro-voids between the columnar grains in the TaNx film. The dense δ-TaN structure with reduced columnar grains and micro-voids increases the strength of the TaNx film.