Data Transmission with Reduced Delay for Distributed Acoustic Sensors

This paper proposes a channel access control scheme fit to dense acoustic sensor nodes in a sensor network. In the considered scenario, multiple acoustic sensor nodes within communication range of a cluster head are grouped into clusters. Acoustic sensor nodes in a cluster detect acoustic signals and convert them into electric signals (packets). Detection by acoustic sensors can be executed periodically or randomly and random detection by acoustic sensors is event driven. As a result, each acoustic sensor generates their packets (50bytes each) periodically or randomly over short time intervals (400ms~4seconds) and transmits directly to a cluster head (coordinator node). Our approach proposes to use a slotted carrier sense multiple access. All acoustic sensor nodes in a cluster are allocated to time slots and the number of allocated sensor nodes to each time slot is uniform. All sensor nodes allocated to a time slot listen for packet transmission from the beginning of the time slot for a duration proportional to their priority. The first node that detect the channel to be free for its whole window is allowed to transmit. The order of packet transmissions with the acoustic sensor nodes in the time slot is autonomously adjusted according to the history of packet transmissions in the time slot. In simulations, performances of the proposed scheme are demonstrated by the comparisons with other low rate wireless channel access schemes.Comment: Accepted to IJDSN, final preprinted versio

Higher-order elastic properties of single crystalline corundum

Corundum is frequently used for high-pressure and high-temperature applications. Its second-order pressure derivatives are, however, not measurable. A static rigid-ion lattice model for corundum, utilizing exponential-type repulsive force, is developed. The lattice parameters are determined from measured data of the bulk modulus and C33. Using these lattice parameters first-order pressure derivatives of bulk modulus and C33 are computed and compared to measured values, respectively. The deviations do not exceed 33%. The second-order pressure derivatives of bulk modulus and C33 are predicted and the results come out positive. These are usually negative for oxide mineral of cubic structure

Effect of Total Leaf Numbers on the Growth and Fruit Quality in Muskmelon Plants Showing Leaf Yellowing Symptoms

This study was conducted to evaluate the influence of total leaf numbers on the growth, net formation of fruits, and occurrence of leaf yellowing symptoms (LYS) in muskmelon plants. The growth and development of LYS on muskmelon plants having 25, 30, and 35 fully expanded leaves on the vine were compared to those of the control plant having 20 leaves. Plant height, leaf area, root fresh weight, and root dry weight increased as the number of leaves increased. Plants with 35 leaves showed the greatest plant growth. Net photosynthetic rate was positively related to increasing leaf numbers with plants having over 25 leaves showing the greatest photosynthetic rates. On the other hand, there were no significant differences in chlorophyll content and root activity among treatments with different leaf numbers. The ratio of LYS infection was also greater in plants having 25-30 leaves, than in those having leaf numbers. Plants with different leaf numbers and LYS infection showed a variation in fruit quality, although LYS did not significantly affect fruit quality except net index. The plants having 20 leaves that showed LYS developed fruits that had significantly smaller flesh (mesocarp) thickness than, the plants having greater numbers of leaves. The higher sugar contents of fruits were found in the plants having 35 leaves whether they showed LYS (12.1°Bx) or not (12.5°Bx). Therefore, leaving more than 25 healthy leaves per plant was recommended for minimizing damage from LYS.OAIID:oai:osos.snu.ac.kr:snu2015-01/104/0000027607/11ADJUST_YN:NEMP_ID:A075898DEPT_CD:517CITE_RATE:0FILENAME:(이희주)effect_of_total_leaf_numbers_on_the_growth_and_fruit_quality_in_muskmelon_plants_showing_leaf_yell··.pdfDEPT_NM:식물생산과학부CONFIRM:

Characterizations of realized metal-insulator-silicon-insulator-metal waveguides and nanochannel fabrication via insulator removal

We investigate experimentally metal-insulator-silicon-insulator-metal (MISIM) waveguides that are fabricated by using fully standard CMOS technology. They are hybrid plasmonic waveguides, and they have a feature that their insulator is replaceable with functional material. We explain a fabrication process for them and discuss fabrication results based on 8-inch silicon-on-insulator wafers. We measured the propagation characteristics of the MISIM waveguides that were actually fabricated to be connected to Si photonic waveguides through symmetric and asymmetric couplers. When incident light from an optical source has transverse electric (TE) polarization and its wavelength is 1318 or 1554 nm, their propagation losses are between 0.2 and 0.3 dB/mu m. Excess losses due to the symmetric couplers are around 0.5 dB, which are smaller than those due to the asymmetric couplers. Additional measurement results indicate that the MISIM waveguide supports a TE-polarized hybrid plasmonic mode. Finally, we explain a process of removing the insulator without affecting the remaining MISIM structure to fabricate similar to 30-nm-wide nanochannels which may be filled with functional material.open8

Long-Term Effects of Obstructive Sleep Apnea and Its Treatment on Open-Angle Glaucoma: A Big-Data Cohort Study

STUDY OBJECTIVES: The relationship between open-angle glaucoma (OAG) and obstructive sleep apnea (OSA) is unclear. The long-term risk for OAG after OSA diagnosis has not been investigated. Therefore, we assessed the risk for OAG among patients with OSA over a 12-year follow-up period using nationwide, population-based data. METHODS: The OSA group was randomly selected from among 3.5 million individuals registered with the National Health Insurance Service. The non-OSA group was obtained through propensity score matching considering several variables. The primary endpoint was glaucoma diagnosis. RESULTS: The OSA and non-OSA groups both included 6,369 individuals. The overall hazard ratio for OAG in the OSA group was 1.42 (95% confidence interval [CI]: 1.19-1.69). In subgroup analysis, the hazard ratio for OAG was 1.94 (95% CI: 1.57-2.41) for those aged \u3e 60 years, 1.50 (95% CI: 1.20-1.89) for those with diabetes mellitus, 1.53 (95% CI: 1.26-1.86) for those with hypertension, and 0.71 (95% CI: 0.52-0.96) for those with a history of OSA surgery. CONCLUSIONS: Over the 12-year follow-up, the risk for OAG increased after OSA diagnosis. Further research will be necessary to determine if treating OSA can mitigate this association. CITATION: Lee T-E, Kim JS, Yeom SW, Lee MG, Lee JH, Lee H-J. Long-term effects of obstructive sleep apnea and its treatment on open-angle glaucoma: a big-data cohort study

Determination of the Prevalence of Infection with Mycobacterium tuberculosis among Persons Vaccinated against Bacillus Calmette-Guérin in South Korea

The prevalence of tuberculous infection was estimated among 12,032 persons with a Bacillus Calmette-Guérin (BCG) vaccination scar and 7,788 persons without such a scar who participated in a nationwide tuberculin skin test survey conducted in the Republic of Korea in 1975. The analysis was built upon mixture models that captured the heterogeneity of indurations arising from tuberculous infection, cross-reactions due to infection with environmental mycobacteria, and BCG vaccination. The three distributions were allowed to vary by age, sex, and BCG vaccination status in the Bayesian manner, according to the prior opinion of the authors. Estimated prevalences of tuberculous infection were similar among persons with a BCG scar and persons without one: 7.5% (95% credibility interval (CI): 3.1, 12.5) and 5.2% (95% CI: 4.2, 6.3), respectively, at age 0-4 years and 87.3% (95% CI: 84.0, 90.2) and 84.0% (95% CI: 81.9, 85.8), respectively, at age 25-29 years. From this analysis it can be concluded that mixture models allow investigators, for the first time, to estimate the prevalence of tuberculous infection not only in unvaccinated persons but also in the BCG-vaccinated population. Mixture models are a versatile tool for analyzing diagnostic test data and more general classification problems of considerable complexit

Competency Modeling and Training Needs Assessment for Staff Development in Higher Education

In the Digital Transformation era, Higher Education Institutions (HEI), including universities are seeking various methods to cope with the digital environment. Human resources management and development can be implemented in the HEI because university staff is the main human capital of HEI. In order to promote the performance of HEI, it is essential to develop the competencies of university staff, including digital literacy. The following research presents a redefinition of competencies for job levels of university staff and the training needs assessment of each competency for the Digital Transformation era. The result of the research implies that HEI should consider the emerging competencies and develop its staff for work efficiency and competitiveness of them in the Digital Transformation era

Validity of gait parameters for hip flexor contracture in patients with cerebral palsy

Background: Psoas contracture is known to cause abnormal hip motion in patients with cerebral palsy. The authors investigated the clinical relevance of hip kinematic and kinetic parameters, and 3D modeled psoas length in terms of discriminant validty, convergent validity, and responsiveness. Methods: Twenty-four patients with cerebral palsy (mean age 6.9 years) and 28 normal children (mean age 7.6 years) were included. Kinematic and kinetic data were obtained by three dimensional gait analysis, and psoas lengths were determined using a musculoskeletal modeling technique. Validity of the hip parameters were evaluated. Results: In discriminant validity, maximum psoas length (effect size r = 0.740), maximum pelvic tilt (0.710), maximum hip flexion in late swing (0.728), maximum hip extension in stance (0.743), and hip flexor index (0.792) showed favorable discriminant ability between the normal controls and the patients. In convergent validity, maximum psoas length was not significantly correlated with maximum hip extension in stance in control group whereas it was correlated with maximum hip extension in stance (r = -0.933, p < 0.001) in the patients group. In responsiveness, maximum pelvic tilt (p = 0.008), maximum hip extension in stance (p = 0.001), maximum psoas length (p < 0.001), and hip flexor index (p < 0.001) showed significant improvement post-operatively. Conclusions: Maximum pelvic tilt, maximum psoas length, hip flexor index, and maximum hip extension in stance were found to be clinically relevant parameters in evaluating hip flexor contracture.Y

Reconfigurable Filter Design

This chapter discusses recent development of reconfigurable filters. The technical terminology reconfigurable means that a circuit is designed in a way to have various electrical characteristics comparing with one which has a static feature. For the filter design, the various electrical characteristics can be considered as the filter can tune its operating frequency, bandwidth, and/or have multiple operational modes, that is, bandstop or bandpass modes. Also, recently, the filters that can exhibit an improved impedance matching performance over its stopband have been reported. It provides more options for the filter designers to realize the reconfigurable filters having reflective and/or absorptive frequency response types to satisfy a prior given requirement. In this chapter, recently devised filter designs will be covered and essential frequency tuning elements to realize the reconfigurable characteristic will be introduced as well