• 제목/요약/키워드: Technology Asymmetry

검색결과 269건 처리시간 0.032초

우렁쉥이(Halocynthia roretzi) 유생의 뇌포 구조와 수압수용쳬의 형성 (Brain Vesicle Structure and Formation of the Hydrostatic Pressure Receptors in Larvae of the Ascidian (Halocynthia roretzi))

  • 김정은;서형주;김길중
    • 한국수산과학회지
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    • 제39권2호
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    • pp.94-99
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    • 2006
  • The tadpole larvae of most ascidians have two sensory pigment cells in their brain vesicle. The anterior otolith pigment cell is sensitive to gravity, whereas the posterior ocellus pigment cell responds to light. Besides these two sensory cells, the larvae also possess another type of sensory receptor cell: hydrostatic pressure receptor (Hpr) cells. The Hpr cells have been presumed to sense hydrostatic water pressure, although no functional analysis has been performed. In larvae of the ascidian Halocynthia reretzi, the development of the Hpr cells and their structure in the brain vesicle are poorly understood. To investigate the morphology and formation of the Hpr cells, we established a monoclonal antibody, Hpr-1, that specifically recognizes Hpr cells. The Hpr-1 antigens became detectable in the brain vesicle at the late tailbud stage. Each Hpr cell projected a small globular body, connected by a short stalk, into the lumen of the brain vesicle. The brain vesicle showed remarkable left-right asymmetry. Pigment cells were located on the right side in the lumen of the brain vesicle, whereas Hpr cells were present in the left side. After metamorphosis, the Hpr cells were observed near the rudimental siphons of the juvenile.

Dynamic Trust Model Based on Extended Subjective Logic

  • Junfeng, Tian;Jiayao, Zhang;Peipei, Zhang;Xiaoxue, Ma
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권8호
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    • pp.3926-3945
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    • 2018
  • In Jøsang's trust model, trust evaluation is obtained through operators, but there are problems with the mutuality and asymmetry of trust and the impact of event weight on trust evaluation. Trust evaluation is updated dynamically and continuously with time and the process of interactions, but it has not been reflected in Jøsang's model. Therefore, final trust evaluation is not accurate, and malicious fraud cannot be prevented effectively. This causes the success rate of interaction to be low. To solve these problems, a new dynamic trust model is proposed based on extended subjective logic (DTM-ESL). In DTM-ESL, the event weight and the mutuality of trust are fully considered, the original one-way trust relationship is extended to a two-way trust relationship, discounting and consensus operators are improved, and trust renewal is designed based on event weight. The viability and effectiveness of this new model are verified by simulation experiments.

A study on the corporate culture of Dianping

  • Wei, Feng-Ping;Choi, Myeong-Cheol;Shang, Xian-Fa
    • International Journal of Advanced Culture Technology
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    • 제7권4호
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    • pp.69-75
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    • 2019
  • In recent years, with the development of IT technology and mobile communication, the powerful communication function of the Internet will gradually eliminate the information asymmetry between supply and demand, and the third-party review website emerges as The Times require. Dianping.com was founded in 2003. After a few years of development, it has become an independent third-party consumer review website worldwide. One of the reasons for such great success is corporate culture, which plays an important role in human resource management. The competition of enterprises is not only the competition of products and cost advantages, but also the superior enterprise culture presented to customers in the international environment. The competition between third-party review sites has been very fierce. In just a few years, many foreign third-party review websites went public and made profits, but some domestic start-ups went bankrupt due to the lack of a good business model and corporate culture. A good business model is particularly important. Taking dianping.com as the research object and combining with the business model of the company, this paper studies the unique corporate culture of dianping.com, hoping to help the company through the investigation and research of this paper, so as to improve the company in the future. And put forward a certain practical significance and value.

Numerical Comparison of Thermalhydraulic Aspects of Supercritical Carbon Dioxide and Subcritical Water-Based Natural Circulation Loop

  • Sarkar, Milan Krishna Singha;Basu, Dipankar Narayan
    • Nuclear Engineering and Technology
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    • 제49권1호
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    • pp.103-112
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    • 2017
  • Application of the supercritical condition in reactor core cooling needs to be properly justified based on the extreme level of parameters involved. Therefore, a numerical study is presented to compare the thermalhydraulic performance of supercritical and single-phase natural circulation loops under low-to-intermediate power levels. Carbon dioxide and water are selected as respective working fluids, operating under an identical set of conditions. Accordingly, a three-dimensional computational model was developed, and solved with an appropriate turbulence model and equations of state. Large asymmetry in velocity and temperature profiles was observed in a single cross section due to local buoyancy effect, which is more prominent for supercritical fluids. Mass flow rate in a supercritical loop increases with power until a maximum is reached, which subsequently corresponds to a rapid deterioration in heat transfer coefficient. That can be identified as the limit of operation for such loops to avoid a high temperature, and therefore, the use of a supercritical loop is suggested only until the appearance of such maxima. Flow-induced heat transfer deterioration can be delayed by increasing system pressure or lowering sink temperature. Bulk temperature level throughout the loop with water as working fluid is higher than supercritical carbon dioxide. This is until the heat transfer deterioration, and hence the use of a single-phase loop is prescribed beyond that limit.

Simulation study of dust-scattered Far-Ultraviolet emission in the Orion-Eridanus Superbubble

  • 조영수;민경욱;임태호;선광일
    • 천문학회보
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    • 제37권2호
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    • pp.98.1-98.1
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    • 2012
  • We present the results of dust scattering simulations carried out for the Orion-Eridanus Superbubble region by comparing them with observations made in the far-ultraviolet. The albedo and the phase function asymmetry factor (g-factor) of interstellar grains were estimated, as were the distance and thickness of the dust layers. The results are as follows: [0.43]_(-0.04)^(+0.02) for the albedo and [0.43]_(-0.2)^(+0.2) for the g-factor, in good agreement with previous determinations and theoretical predictions. The distance of the assumed single dust layer, modeled for the Orion Molecular Cloud Complex, was estimated to be ~110 pc, and the thickness ranged from ~130 at the core to ~50 pc at the boundary for the region of present interest, implying that the dust cloud is located in front of the superbubble. The simulation result also indicates that a thin (~10 pc) dust shell surrounds the inner X-ray cavities of hot gas at a distance of ~70-90 pc.

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Knowledge Distribution in the Science and Technology Space (Case of the Eurasian Economic Union)

  • Farida ALZHANOVA;Gulnaz ALIBEKOVA;Farkhat DNISHEV;Nazyken BAGAYEVA
    • 유통과학연구
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    • 제21권9호
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    • pp.81-91
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    • 2023
  • Purpose: The article aims to assess the possibilities and contribution of countries to the creation and distribution of knowledge circulating in the scientific and technological space of the EAEU. Research design, data, and methodology: To understand the conditions and possibilities for the distribution of knowledge, the methodology of the quality of economic space used. The space is considered through density, placement, connectedness, and asymmetry. Used bibliometric analysis, balance of payments analysis, and integration indicators. Results: The study showed that low barriers, including language, created visible advantages in the mutual distribution of knowledge. However, the geo-technological space of the EAEU is polarised and has differences in the density and distribution of scientific resources. Asymmetries are shown in the distance between countries in multidirectional trends. Cooperation between countries has a different level of interaction. Conclusions: The internal resources of the geo-technological space of the EAEU are limited, and most of the needs are covered by external sources. Some mechanisms of the scientific policy of countries in scientific careers act as «demotivates» for distributing knowledge within the EAEU. Countries need to improve the quality of services and trade data to better understand technology distribution processes through bilateral channels.

비대칭 Polysulfone계(PS/PES/PPS)막 제조시 물리적 인자의 영향 및 기체투과 특성 (Physical Properties and Permeation Characteristics of Polysulfone group(PS/PES/PPS) membrane for Gas Permeation)

  • 박영해
    • 한국산업융합학회 논문집
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    • 제4권1호
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    • pp.77-85
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    • 2001
  • This paper was to investigate the preparation of polysulfone(PS), polyethersulfone(PES) and polyphenylsulfone(PPS) membrane. The thermal property of PPS was higher than that of others. From the result of SEM, the concentration of polymer was found to have a significant effect on the structure of membrane, and the structure of membrane made of PES is found to have regular micell form of asymmetry. Permeability and selectivity for oxygen and nitrogen gas in the air were analyzed by GC. Permeabilities of the membrane made of PES for oxygen and nitrogen in air, 1.5 and $0.7(x10^9[cm^3(STP)cm/cm^2seccmHg]) $, respectively was higher than that of others. and Selectivity of the membrane made of PPS for oxygen to nitrogen gas in air was 2.9.

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Structural Arrangement of Water Molecules around Highly Charged Nanoparticles: Molecular Dynamics Simulation

  • Kim, Eunae;Yeom, Min Sun
    • Bulletin of the Korean Chemical Society
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    • 제35권5호
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    • pp.1501-1505
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    • 2014
  • Molecular dynamics simulations were performed to understand the structural arrangement of water molecules around highly charged nanoparticles under aqueous conditions. The effect of two highly charged nanoparticles on the solvation charge asymmetry has been examined. We calculated the radial distribution functions of the components of water molecules around nanoparticles which have four charge types at two different salt concentrations. Even though the distributions of water molecules surrounding a sodium ion and a chloride ion are hardly affected by the charges of nanoparticles and the salt concentrations, those around highly charged nanoparticles are strongly influenced by the charges of nanoparticles, but hardly by the charges of nanoparticles and salt concentrations. We find that the distributions of hydrogen atoms in water molecules around one highly charged nanoparticle are dependent on the magnitude of the nanoparticle charge.

비대칭 다단 두께 변화를 고려한 결정입 제어 반용융 알루미늄 소재의 캐스팅에서 사출속도가 액상편석에 미치는 영향 (The Effect of Injection Velocity on Liquid Segregation of Grain Controlled Rheological Material Considering Asymmetry Multi Thickness Variation)

  • 서판기;정용식;강충길
    • 소성∙가공
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    • 제14권4호
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    • pp.338-350
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    • 2005
  • Recently, in the field of automobile industry, to solve the problem of reducing the weight of automobile for the improvement of fuel efficiency and the protection of environment, the aluminum alloy parts have been substituted for the steel parts. However, the aluminum alloy does not have as good mechanical property as the steel part. To improve the mechanical property, the semi-solid die casting process is performed to make automobile parts. In the fabrication of semisolid material the control of the liquid segregation is very important to improve the material properties of aluminum alloy. In the present paper we examine the influence of the liquid segregation by the injection conditions in the semi-solid die casting has been investigated.

Kelvin Ship Wake Modification due to Wind Waves

  • ;;안정선
    • 한국해양공학회지
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    • 제22권5호
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    • pp.1-6
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    • 2008
  • A kinematics model of a ship wake in the presence of surface waves generated by wind is presented. It was found that a stationary wave structure behind a ship covered a wedge region with the angle at the top of the wake and that only divergent waves were present in a ship wake instead of both the longitudinal and cross-waves, which are known as the Kelvin model. Ship motion at some angle to wind waves can cause an essential asymmetry of the wake, compressing its windward half.