Miracle-dz/UniFAR-FTUs huggingface dataset:
Propagation Environment Analysis and Wireless Mesh Network Implementation for monitoring the Four Rivers (based on Hapcheon weir)

Four river project in the South Korea contributes to solve flood damages and water shortages. Also, it has purpose for creating water ecosystem and improving the level of people` cultural leisure and quality of life through inducing water quality improvement and river restoration. It is necessary to monitor a variety of observing data in river areas among dozens to hundreds of kilometer for safe river administration. The 20th construction area of the four river project is located on Hapcheon areas, where wireless mesh network was installed to manage the basin. In the process of network construction, the characteristic of surrounding areas is considered about embodying secure service by investing the least expense. Besides, transmission environment analysis is performed such as LOS tests and reception level analysis, and transmission speed measurement to create safe service. Reception level in all places is confirmed among -55 dBm ~ -70 dBm, and data transmission speed proves more than 20 Mbps.
Stardust in Antarctic micrometeorites

Abstract— We report the discovery of presolar silicate, oxide (hibonite), and (possibly) SiC grains in four Antarctic micrometeorites (AMMs). The oxygen isotopic compositions of the eighteen presolar silicate (and one oxide) grains found are similar those observed previously in primitive meteorites and interplanetary dust particles, and indicate origins in oxygen‐rich red giant or asymptotic giant branch stars, or in supernovae. Four grains with anomalous C isotopic compositions were also detected. 12C/13C as well as Si ratios are similar to those of mainstream SiC grains; the N isotopic composition of one grain is also consistent with a mainstream SiC classification.
In vitro cytotoxicity of resin cement and its influence on the expression of antioxidant genes

ABSTRACT Aim: This study evaluated cytotoxicity and antioxidant gene expression of resin cements on human gingival fibroblasts (hGF). Materials and Method: RelyX Ultimate™(RXU), Variolink™II(VLII), and RelyXU200™(RXU200) resin cements were incubated with culture medium for 24 h to obtain eluates. Then, the eluates were applied over hGF to assess cell viability at 24 h, 48 h, and 72 h and antioxidant gene expression at 24 h. hGF cultures non-exposed to the eluates were used as Control. Data were submitted to ANOVA and Bonferroni tests (α≤0.05). Results: RXU and RXU200 reduced the number of viable cells in 24 h. Longer exposure to cement extracts caused cell death. Gene expression showed peroxiredoxin 1 (PRDX1) induction by all resin cement types, and superoxide dismutase 1 (SOD1) induction by RXU200 and VLII. Moreover, RXU200 induced not only PRDX1 and SOD1, but also glutathione peroxidase 1 (GPX1), catalase (CAT), and glutathione synthetase (GSS). Conclusions: All resin cements showed toxicity, and induced antioxidant genes in hGF. Antioxidant gene induction is at least partly associated with cytotoxicity of tested cements to oxidative stress experience.
The research on automatic white balance for digital microscope

Automatic white balance plays a key role in digital color imaging system based on CCD/CMOS sensors. The gray world method and its variants are widely used for their simplicity. However, they will fail if the image is dominated by only one or two colors. The iterative method, which extracts gray color points from the image for color temperature estimation, performs well if there are enough gray color points. But it does not work in the case of serious color casts or lack of gray color points. Thus, a new method is proposed combining the iterative method and the gray world method. The iterative method is for fine adjustment, while the gray world method is for coarse adjustment. The characteristics of the digital microscope are taken into account as well. There are three major contributions in the paper. First, brightness constraint is considered during the gray color points detection. The detecting procedure is more precise as a result. Second, each frame of the video stream is divided into n-by-n blocks so as to increase the immunity to the noise. Last, the fine adjustment and the coarse adjustment are combined together. The 'Fine-Coarse-Fine' routine adjusts the image properly even though there are not sufficient gray color points. Experiments on digital microscope indicate that the proposed automatic white balance method is robust, effective and efficient.
DSM generation and evaluation from QuickBird stereo imagery with 3D physical modelling

A digital terrain model (DTM) extracted from QuickBird in-track stereo images using a three-dimensional (3D) multisensor physical model developed at the Canada Centre for Remote Sensing, Natural Resources Canada was evaluated. Firstly, the stereo photogrammetric bundle adjustment was set-up with about 10 accurate ground control points and 1-2 m errors in the three axes were obtained over 48 independent checkpoints. The DTM was then generated using an area-based multi-scale image matching method and 3D semi-automatic editing tools and then compared to lidar elevation data with 0.2-m accuracy. An elevation error with 68% confidence level (LE68) of 6.4 m was achieved over the full area. Since the DTM is in fact a digital surface model where the height, or a part, of land cover (trees, houses) is included, the accuracy depends on the land cover types. Using 3D visual classification of the stereo QuickBird images, different classes (deciduous, conifer, mixed and sparse forests, residential areas, bare soils and lakes) were generated to take into account the height of the surfaces (natural and human-made) in the accuracy evaluation. LE68 values of 3.4 m to 6.7 m were thus obtained depending on the land cover types with biases representative of the surface heights. On the other hand, LE68 values of 0.5 m and 1.3 m with no bias were obtained for lakes and bare soils respectively. These last results are more representative of the real stereo QuickBird potential for DTM and 5-m contour line generation, compliant with the highest topographic standard. Since the images were acquired in wintertime and the lidar data in summertime, better results could thus be expected when using stereo images acquired in summertime, mainly in deciduous forests to integrate the full canopy height into the DSM.
SPADE: Secure Periodic Advertising using Coded Time-Channel Rendezvous for BLE Audio

Periodic advertising is an extended advertisement mechanism introduced in Bluetooth 5.0 that broadcasts time-synchronized data to multiple scanners. It is an essential operation in Auracast, a Bluetooth Low Energy (BLE) audio broadcast mechanism newly defined in 2022, which enables audio sharing applications such as hearing aid and public announcement. However, its unencrypted metadata distribution and lack of authentication make it vulnerable to simple yet destructive attacks. In this work, we first show that a selective jammer can easily and significantly degrade the performance of periodic advertising by precisely jamming only the SYNC (auxiliary synchronize indicator) packets. Then to defend against this attack, we propose SPADE as a countermeasure, a secure periodic advertising scheme using coded time-channel rendezvous and feedback. In SPADE, the broadcaster assigns a Hamming- code based device-specific time-channel sequence to each scanner using short connections. Then, it receives light-weight feedback on repetitive packets from the scanners to discriminate the jammer and update new metadata to the scanners so that the jammer is rejected. We implement SPADE on real BLE devices, and evaluate through both experiments and simulations to show over 80 % PRR even under selective jamming attacks.
Strategies for becoming a more desirable mate: Evidence from 14 countries

The current research aimed to study the strategies that people employ in order to become more desirable as mates in different cultural settings. More specifically, using a closed‐ended questionnaire on a sample of 7181 participants from 14 different countries, we identified 10 different strategies that people employ to become more appealing as mates. Participants indicated that they had more frequently used the “Enhance looks,” followed by the “Show off abilities and talents,” and the “Demonstrate similarity” strategies. On the other hand, they had less frequently used the “Keep undesirable things hidden,” the “Show off and exaggerate wealth and abilities,” and the “Drastic appearance changes” strategies. Female participants indicated that they had more extensive used the “Enhance looks” strategy than male participants, while male participants indicated that they had more extensive used the “Increase income and social status” and the “Show off and exaggerate wealth and abilities” strategies than female participants. The sex effects, as well as the extent of use, were generally consistent across the different cultures. The identified strategies were classified further into two main strategies, namely the “Develop and demonstrate desirable traits” and the “Deceive about undesirable traits,” which was generally consistent across the different countries.
Estimating turbulent fluxes through assimilation of geostationary operational environmental satellites data using ensemble Kalman filter

[1] In this study, a data assimilation scheme is developed on the basis of the ensemble Kalman filter algorithm and the common land model (CoLM); soil moisture and model parameters are simultaneously optimized to improve the estimates of turbulent fluxes. Land surface temperature (LST) is retrieved from geostationary operational environmental satellites (GOES) data, validated, and then assimilated into the model. The data assimilation results are validated at six observation sites in the United States that include grassland, cropland, and forestland cover types. Data assimilation results indicate that in addition to improvements in the prediction of turbulent fluxes, model uncertainties are also reduced as a result of the assimilation of GOES LST retrieval data. The average reductions in root mean square error (RMSE) values are 47.5 and 31.1 W m−2. The effects of simultaneous optimization of soil moisture and model parameters are compared with those resulting from separate optimization; simultaneous optimization is found to yield smaller RMSE values. Further, in this study, the effects of Moderate Resolution Imaging Spectroradiometer (MODIS) and GOES temporal resolution data on data assimilation results are studied. The assimilation results indicate that the average RMSE values for GOES temporal resolution data are smaller than that for MODIS temporal resolution data. During the assimilation time period, the soil moisture obtained from assimilation closely agrees with the observed values, and the four vegetation parameters show distinct seasonal variations. However, the lack of sufficient information makes it difficult to estimate the true value of these variables and parameters.
Prediction of iceberg trajectories for the North Atlantic and Arctic oceans

Icebergs are a well-known hazard for shipping. Their study also provides information about diverse geophysical processes, as varied as ocean circulation, air-sea fluxes, calving rates of glaciers or the mass balance of ice sheets. As a first step to obtaining this information from iceberg data we have developed a model of iceberg drift driven by ocean and atmospheric forcing derived from general circulation models. We have applied the drift model to a distribution of typical icebergs released from the main tidewater glaciers of the North Atlantic and Arctic Oceans. We demonstrate that the main driving force of iceberg motion is rooted in the unsteady component of oceanic advection. From simulated trajectories we are able to reproduce the observed southwards limit of iceberg penetration and demonstrate sometimes surprising geographical links between iceberg origin and ultimate melting zones.
Ship detection and classification in high-resolution remote sensing imagery using shape-driven segmentation method

High-resolution remote sensing imagery provides an important data source for ship detection and classification. However, due to shadow effect, noise and low-contrast between objects and background existing in this kind of data, traditional segmentation approaches have much difficulty in separating ship targets from complex sea-surface background. In this paper, we propose a novel coarse-to-fine segmentation strategy for identifying ships in 1-meter resolution imagery. This approach starts from a coarse segmentation by selecting local intensity variance as detection feature to segment ship objects from background. After roughly obtaining the regions containing ship candidates, a shape-driven level-set segmentation is used to extract precise boundary of each object which is good for the following stages such as detection and classification. Experimental results show that the proposed approach outperforms other algorithms in terms of recognition accuracy.
Potassium-argon ages and magnetic properties of some dredged submarine basalts and their geophysical implications

Magnetic properties and K-Ar ages of five basalts dredged from the western Pacific and two from the East Pacific rise area were studied. The western Pacific samples have an age of a few ten million years, whereas the eastern Pacific sample has a much younger age of about 3 m.y. Most of the samples have intensities of NRM of about 3 × 10−3 emu/cc and susceptibility of about 10−4 emu/cc. Three of the seven dredged basalts studied here showed self-reversal of thermoremanent magnetization upon heating to 300°C in air. Q ratios range from 5 to 57. Judging from the comparison between the thermal decay of NRM and the production of TRM, the NRM of most samples seems to be of TRM origin. These experiments also suggest that the geomagnetic field intensity when these rocks were formed was not much diffrent from the present one. Both Curie temperature Θ and saturation magnetization Is of the submarine basalts increase markedly when they are heated in air or in vacuum. The Is generally increases by a factor of more than 3. Such irreversible increase of Is and Θ is also studied on the ferromagnetic separates from the experimental Mohole basalt. From thermomagnetic, chemical, and X-ray analyses and microscopic observation, it is suggested that these abnormal increases of Θ and Is are caused by rearrangements of ionic configuration in titanomaghemite. On the basis of these magnetic characteristics and K-Ar ages of the submarine basalts, an interpretation of magnetic anomaly lineation pattern of the ocean floor is presented.
Determination of genetic correlation between tobacco smoking and coronary artery disease

Backgrounds Tobacco smoking is an important risk factor for coronary artery disease (CAD), but the genetic mechanisms linking smoking to CAD remain largely unknown. Methods We analyzed summary data from the genome-wide association study (GWAS) of the UK Biobank for CAD, plasma lipid concentrations (n = 184,305), and smoking (n = 337,030) using different biostatistical methods, which included LD score regression and Mendelian randomization (MR). Results We identified SNPs shared by CAD and at least one smoking behavior, the genes where these SNPs are located were found to be significantly enriched in the processes related to lipoprotein metabolic, chylomicron-mediated lipid transport, lipid digestion, mobilization, and transport. The MR analysis revealed a positive correlation between smoking cessation and decreased risk for CAD when smoking cessation was considered as exposure (p = 0.001), and a negative correlation between the increased risk for CAD and smoking cessation when CAD was considered as exposure (p = 2.95E-08). This analysis further indicated that genetic liability for smoking cessation increased the risk of CAD. Conclusion These findings inform the concomitant conditions of CAD and smoking and support the idea that genetic liabilities for smoking behaviors are strongly associated with the risk of CAD.
The Strength of the Earth's Crust

The strength of the crust has been tested in the first part of this paper by those geologic changes which alter the surface of the earth, but not the density of its interior. If these changes in load initiate rather than merely coincide with vertical movements which serve to diminish the stress, they are thereby shown to be greater than the earth can permanently endure. If, on the other hand, the constructional forms persist, as in the two great deltas studied, then the movements which may exist in the crust due to those loads must be slower at least than the process of surface construction. Such loads consequently, unless counterbalanced by some factor not apparent, are within the limits of crustal strength. But surface changes and the loads implied can be measured only in special cases. The previous attitude of the crust and the degree and direction of strain then existing in it are complicating factors which it is difficult quantitatively to evaluate. For these reasons the evidence yielded by geodetic investigation promises, in the end, more general and more accurate results.
Research on the geometry rectification model of CCD image of HJ satellite with sparse ground control points

Linear array CCD push-broom imaging system is adopted by CCD camera of HJ satellite as its imaging system. With the support of satellite ephemeris, attitude and the knowledge for CCD camera, a rigorous sensor model for CCD image of HJ satellite is constructed. Meanwhile, an error reduction model based on polynomial transformation using a few GCPs is used to compensate the positioning error. Experiments show that positioning error is about 185 pixels without GCPs, and it can be reduced to four pixels when three GCPs are used to compensate the positioning error.
Collaborative Virtual Reality in Higher Education: Students' Perceptions on Presence, Challenges, Affordances, and Potential

The metaverse is a network of interoperable and persistent 3-D virtual worlds where users can coexist and interact through mechanisms, such as gamification, nonfungible tokens, and cryptocurrencies. Although the metaverse is a theoretical construct today, many collaborative virtual reality (CVR) applications have emerged as potential components of the metaverse. The demand for distance learning in higher education grew rapidly with COVID-19, but it has many challenges such as low motivation, low interest, and lack of suitable environment. We investigated the suitability of CVR applications for higher education by analyzing 9 existing CVR applications and then conducting a mixed-method user study on the Spatial CVR application with 41 university students (24 females, 17 males, mean age: 23.5). The results revealed 14 challenges, 13 affordances, and 20 ideas for using CVR in higher education. Moreover, lack of instructions, cybersickness, discomfort, limited embodiment, and limited sensory stimulation were among the identified issues that may inhibit the sense of presence in Spatial. Based on the findings, we proposed 13 guidelines to facilitate providing CVR learning in higher education and concluded that CVR has some use cases in higher education to complement conventional methods. These results can be useful for researchers, developers, and educators who seek to be at the forefront of adopting CVR as a part of the metaverse to come.
Particle size distribution properties in mixed‐phase monsoon clouds from in situ measurements during CAIPEEX

A comprehensive analysis of particle size distributions measured in situ with airborne instrumentation during the Cloud Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX) is presented. In situ airborne observations in the developing stage of continental convective clouds during premonsoon (PRE), transition, and monsoon (MON) period at temperatures from 25 to −22°C are used in the study. The PRE clouds have narrow drop size and particle size distributions compared to monsoon clouds and showed less development of size spectra with decrease in temperature. Overall, the PRE cases had much lower values of particle number concentrations and ice water content compared to MON cases, indicating large differences in the ice initiation and growth processes between these cloud regimes. This study provided compelling evidence that in addition to dynamics, aerosol and moisture are important for modulating ice microphysical processes in PRE and MON clouds through impacts on cloud drop size distribution. Significant differences are observed in the relationship of the slope and intercept parameters of the fitted particle size distributions (PSDs) with temperature in PRE and MON clouds. The intercept values are higher in MON clouds than PRE for exponential distribution which can be attributed to higher cloud particle number concentrations and ice water content in MON clouds. The PRE clouds tend to have larger values of dispersion of gamma size distributions than MON clouds, signifying narrower spectra. The relationships between PSDs parameters are presented and compared with previous observations.
A Mechanism for the Recurrence of Wintertime Midlatitude SST Anomalies

Abstract In the early 1970s, Namias and Born speculated that ocean temperature anomalies created over the deep mixed layer in winter could be preserved in the summer thermocline and reappear at the surface in the following fall or winter. This hypothesis is examined using upper-ocean temperature observations and simulations with a mixed layer model. The data were collected at six ocean weather stations in the North Atlantic and North Pacific. Concurrent and lead-lag correlations are used to investigate temperature variations associated with the seasonal cycle in both the observations and the model simulations. Concurrent correlations between the surface and subsurface temperature anomalies in both the data and the model indicate that the penetration of temperature anomalies into the ocean is closely tied to the seasonal cycle in mixed layer depth: high correlations extend to relatively deep (shallow) depths in winter (summer). Lead-lag correlations in both the data and the model, at some of the stations, .
Firm failure causes: a population level study

Business failure may be the result of either voluntaristic (internal) firm actions/decisions, deterministic environmental (external) events or both given causes (integrative approach). This study examines the prevalence of these causes of business failure. Results indicate that the largest proportion of firm failures is explained by the integrative approach, although two other perspectives hold a prominent role also. Moreover, internal causes of failure are more frequent than external. The findings based on multinomial logistic regression revealed that the causes of failure also vary with the size and age of firms. The implications of the results for research and practice are discussed.