• Title/Summary/Keyword: Effective Mass

Search Result 2,691, Processing Time 0.036 seconds

Evaluation Research on Smart Mirror UX for Efficient Communication of the IoT Generation (IoT 시대 효과적인 커뮤니케이션을 위한 스마트미러 UX 평가 연구)

  • Oh, Moonseok
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.11 no.1
    • /
    • pp.121-133
    • /
    • 2015
  • IoT utilized network vitalization between objects are being rapidly established within current IT communication environment. Therefore the worth of smart mirrors is rising for it is a tool to allow online network between objects to be possible in human communication environment. For effective IoT generation's communication, this research intends to evaluate the smart mirror's value for practical uses based on the users' experiences. For the UX evaluation according to the locations where it will be used, Peter Morville's Honeycomb model and Jocob Nielsen's usage evaluation principles were referred to analyze effectiveness of 4 factors, utilization convenience, communication effectiveness, mass interest and space adequateness on households, public places and work places. Hence, we have were led to an objective result through statistical analysis method based on survey. As a result, we have confirmed the smart mirror's positive influence on the users' effective communication in all places. Especially in households, utilization convenience and space adequateness appeared to be high that confirmed sufficient users' need for the home-automation services. In public places, the communication effectiveness and space adequateness ranked high to confirm that the smart mirror utilization is adequate to provide location information. Also, in work places, the mass adequateness was high that we were able to confirm that supply of work place-specific service contents would bring meaningful results to the users. The smart mirrors are the adequate method to provide effective communication in IoT generation with high possibilities in further development.

A Density Functional Study of Furofuran Polymers as Potential Materials for Polymer Solar Cells

  • Xie, Xiao-Hua;Shen, Wei;He, Rong-Xing;Li, Ming
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.10
    • /
    • pp.2995-3004
    • /
    • 2013
  • The structural, electronic, and optical properties of poly(3-hexylthiophene) (P3HT) have been comprehensively studied by density functional theory (DFT) to rationalize the experimentally observed properties. Rather, we employed periodic boundary conditions (PBC) method to simulate the polymer block, and calculated effective charge mass from the band structure calculation for describing charge transport properties. The simulated results of P3HT are consistent with the experimental results in band gaps, absorption spectra, and effective charge mass. Based on the same calculated methods as P3HT, a series of polymers have been designed on the basis of the two types of building blocks, furofurans and furofurans substituted with cyano (CN) groups, to investigate suitable polymers toward polymer solar cell (PSC) materials. The calculated results reveal that the polymers substituted with CN groups have good structural stability, low-lying FMO energy levels, wide absorption spectra, and smaller effective masses, which are due to their good rigidity and conjugation in comparison with P3HT. Besides, the insertion of CN groups improves the performance of PSC. Synthetically, the designed polymers PFF1 and PFF2 are the champion candidates toward PSC relative to P3HT.

Detail relation of negative ion density with positive ion mass and sheath parameters

  • Kim, Hye-Ran;Woo, Hyun-Jong;Sun, Jong-Ho;Chung, Kyu-Sun
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.02a
    • /
    • pp.470-470
    • /
    • 2010
  • Negative ions are generated in fusion edge plasmas, material processing plasmas, ionospheric plasmas. Analytic formulas for the deduction of the absolute density of negative ions was given by using the current-voltage(IV) characteristics of two electric probes at two different pressures [1], and negative ion density has been measured by one electric probe using the current-voltage characteristics of three different pressures [2]. Ratios of ion and electron saturation currents and electron temperatures and sheath areas of different pressures are usually incorporated into two equations with two unknowns for the negative ion density. In the previous publications, the sheath factor(sheath area, sheath density, sheath velocity) and effective masses of background ions with different pressures are qualitatively incorporated for the deduction of negative density. In this presentation, the quantitative and detailed relation of negative ion density with sheath factor and effective masses are going to be given. The effect of these parameters on the change of IV characteristics will be addressed.

  • PDF

Acaricidal effects of herb essential oils against Dermatophagoides farinae and D. pteronyssinus (Acari: Pyroglyphidae) and qualitative analysis of a herb Mentha pulegium (pennyroyal)

  • Rim, In-Sook;Jee, Cha-Ha
    • Parasites, Hosts and Diseases
    • /
    • v.44 no.2 s.138
    • /
    • pp.133-138
    • /
    • 2006
  • This experiment was undertaken to screen the acaricidal effects of herb essential oils (pennyroyal, ylang ylang, citronella, lemon grass, tea tree, and rosemary) at different doses (0.1, 0.05, 0.025, 0.0125, and $0.00625{\mu}l/cm2$) and exposure times (5, 10, 20, 20, 30 and 60 min) on house dust mites Dermatophgoides farinae and D. pteronyssinus. The most effective acaricidal components of pennyroyal (Mentha pulegium) were analyzed using a gas chromatography-mass spectrometer (GC-MS). Of these essential oils, the most effective was pennyroyal, which is composed essentially of pulegone (> 99%), at a dose of $0.025{\mu}l/cm^2$, which at an exposure time of 5 min killed more than 98% of house dust mites. In the pennyroyal fumigation test, the closed method was more effective than the open method and maximum acaricidal effect was 100% at $0.025{\mu}l/cm^2$, 60 min. The results show that herb essential oils, in particular, pennyroyal was proved to have potent acaricidal activity.

The Effect of Environmental Parameters on Frost Formation on a Horizontal Cylinder (수평 실린더에서의 서리 생성에 대한 환경 변수들의 영향)

  • Lee, Yun-Bin;Ryu, In-Sang;No, Seung-Tak
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.26 no.2
    • /
    • pp.253-260
    • /
    • 2002
  • It is known that frost formation on surfaces of the heat exchanger seriously affects the performance of the refrigeration system. Accordingly, defrosting should follow, and effective defrosting is possible only when both analytic tools and comprehensive experimental data on frost formation are assailable. An experimental investigation was undertaken to characterize the effect of environmental parameters on frost formation on a horizontal cylinder in cross uniform flow. Several experiments were carried out with various environmental parameters such as inlet air temperature, inlet air humidity, air velocity and cooling surface temperature. Frost thickness, mass, surface temperature and cylinder inner and outer temperature were measured at front and rear positions of the cylinder. Thickness, mass, density, and effective thermal conductivity of the frost layer were obtained from measured data and effects of environmental parameters on the frost formation were analyzed. Data from experiments were correlated using dimensionless variables.

Estimation of Natural Frequency of Reinforced Concrete Slab (철근콘크리트 슬래브의 고유진동수 추정)

  • Woo, Woon-Taek
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.4 no.4
    • /
    • pp.219-223
    • /
    • 2000
  • The evaluation of habitability to building vibration is conducted by the values of natural frequency, amplitude displacement, damping ratio. These values can be obtained from test or analytical results. Data acquisition through test may be possible in existing building, however, to estimate the serviceability of the building, it is necessary to evaluate those values at the stage of design. The natural frequency is important and basic factor for the evaluation of the serviceability. Calculation method of the effective stiffness in RC slab is proposed. To prove the efficiency of the proposed method, sample results of the analysis and the test are compared. These results proved that the effective width proposed to calculate the effective stiffness is proper to evaluate the natural frequency.

  • PDF

The effects of particle shape on the effective thermal conductivity enhancement of nanofluids (나노유체 입자상 모양의 유효 열전도도에의 영향)

  • Koo, June-Mo;Kang, Yong-Tae
    • Proceedings of the KSME Conference
    • /
    • 2008.11b
    • /
    • pp.2106-2109
    • /
    • 2008
  • Nanofluids have been studied as possible alternatives for heat transfer fluids to improve the efficiency of heat exchangers. There are deviations of measured effective thermal conductivities between research-groups, and the mechanisms of the effective thermal conductivity enhancement of nanofluids are not confirmed yet. In this study, the effects of particle shape on the effective thermal conductivity enhancement are discussed and presented as a possible explanation of the deviations. The particle motion effect is found to be negligible for nanofluids of high aspect ratio cylindrical particles, which is believed to be important for nanofluids of spherical particles, while the percolation network formation and contact resistance play dominant roles in determining the effective thermal conductivity.

  • PDF

Performance Evaluation of TMD and TLCD for Earthquake-Induced Response Control (TMD와 TLCD의 지진응답에 대한 제어성능 평가 연구)

  • 김홍진;김형섭;민경원;오정근
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.7 no.5
    • /
    • pp.85-91
    • /
    • 2003
  • TLCD is a good alternative to TMD for control of structures because of its cost efficiency, ease of installation, little maintenance requirement, potential for multiple usage, and ease of re-tuning. In this study, the control performances of TMD and TLCD are evaluated and compared for seismically excited structures. Results show that TLCD is more effective than TMD for interstory drift control while TLCD is as effective as TMD for acceleration control. In special. it is shown that interstory drifts are maximally controlled in lower floors and accelerations are reduced most in upper floors. This indicates that TLCD is an effective controller for earthquake-induced structures in terms of structural safety as well as serviceability.

Field Application of Egg and Larval Parasitic Fungi and Chemicals for Controlling Root-knot Nematodes on Some Medicinal Herb (몇종의 선충천적 진균과 화학약제를 이용한 약용작물 뿌리혹선충 방제효과 검토)

  • 박소득;추연대;정기채;심용구;최영연
    • Korean journal of applied entomology
    • /
    • v.32 no.1
    • /
    • pp.105-114
    • /
    • 1993
  • Series of studies were conducted to establish biological and chemical control method for Meloidogyne spp to medical herbs by applied of nematophagous fungi, Arthrobotrys spp, Fusarium spp, and egg parastic fungi, Paecilomyces lilacinus were applied for root-knot nematodes on medicinal herbs, Paeonia albiflora, Codonopsis lanceolata, Cnidium officinale. The results are as follow. In pot experiments, The no. of root gall and egg mass and larvae of Cnidium officinale. The results are as follow. In pot experiments. The no. of root gall and egg mass and larvae of Cnidium officinale, Codonopsis lanceolata, Paeonia japonica lowered in P. Lilacinus treated plots compare to untreated control plots. But A. thaumasia F. oxysporum treated plots were less effective. Effect of egg parasitic fungi and chemical treatment at divided root of Paeonia japonica after sterilized in pot were increased in the fresh weight, root weight, control effect in P. lilacinus treated plots as chemical, Carbo G treated plots compare to untreted control plots. I field experiment, the number of root gall, egg mass and nematode density of Paeonia were also suppressed in P. lilacinus treated plots. It was very effective continuous 2 years and transplanting time on Paeonia japonica infested soil with the M. hapla in field in both region, Chillgok and Euisung treated P. lilacinus as chemical treated plots. Soaking effect of insecticide for Paeonia japonica at diving shoot before transplating in pot were effective for 12hours immersion into 1,000 ppm of Benlate T + Mep Ec, Benlate T + Fenthion EC in pot and field Experiment. In the Examination of fungi activily on P.japonica field 1 year after soil treatment, Number of spore of P. lilacinus were 1,000~1,300 in 3 region except Euisung.

  • PDF

Case report of Kimura's disease Treated by Radical resection and Post Operative Steroid therapy (기무라 병 환자에서 수술적 치료 및 술 후 스테로이드 병합요법의 치험2례)

  • Kim, Jeong Tae;Kim, Kee woong;Lee, Kyoung mook;Kim, Youn Hwan
    • Archives of Plastic Surgery
    • /
    • v.36 no.2
    • /
    • pp.229-232
    • /
    • 2009
  • Purpose: Kimura's disease is a relatively rare head and neck tumor that frequently occurs in young orientals accompanied with eosinophila. We shared our experience of two cases of Kimura's disease, treated by radical resection and post operative steroid therapy, so we report the correlation of eosinophil counts and disease progression. Methods: A 25 years old male came to the clinic with a mass localized to the right cheek inferior to the right auricle. We could not resect the mass totally. During the follow up period, we checked the eosinophil counts, and steroid therapy was started 7 months after the surgery. A 34 year old female came to the clinic with a mass localized inferior to the left auricle reaching from the posterior portion of the auricle to the left temporal portion. We tried to remove as much tumor as possible, save the temporal region, in regard to the impairment of blood supply to the auricle. After operation, steroid therapy was started. Results: In the first case, the tumor was easily approachable, and radical resection of the tumor with post operative steroid therapy was an effective treatment. In tumors located at difficult regions to remove, as in the second case, optimal debulking and post operative steroid therapy was also effective in treating Kimura's. There were no recurrences in both cases. Eosinophil counts were always reduced after surgery and steroid therapy, and during the period with low eosinophil counts, there was no recurrence of Kimura's disease. Conclusion: Surgery and post operative steroid therapy were effective in treatment of Kimura's disease, and we could assume eosinophil counts as a good indicator for evaluation of the prognosis of Kimura's disease during the follow up period.