Birds in flight are prone to collide with various transparent or reflective structures. While bird–window collision has been recognised as a critical conservation issue, collision with other transparent structures has been less understood. Noise barriers made of transparent materials are considered critical hazards for birds; however, little is known about the bird mortality they cause. We conducted the first nationwide-scale estimates of bird-collision mortality caused by transparent noise barriers (TNBs) along roads in the Republic of Korea. The total length of existing roadside transparent noise barriers was estimated at 1,416 km nationwide (as of 2018), and it had been increasing exponentially. Based on carcass surveys at 25 sites, daily mortality at the observed barriers was 0.335 ± 1.132 birds/km on average, and no difference in observed mortality was detected between both sides of a single barrier and between road types (i.e. local roads and motorways). Finally, we estimated that approximately 186,000 birds (95% confidence interval: 162,465–204,812 birds) are killed annually by collisions with roadside TNBs. As privately installed barriers were not considered in this study, the actual mortality is likely be higher than our estimates. Thus, collision with TNBs could become an emerging threat to avian conservation, especially in developing and urbanising regions around the world. As such structures are not formally recognised as conservation issues of importance, more systematic surveys aided by citizen science, both for the status of TNBs and bird-collision mortality, are needed in addition to management and mitigation policies.

Globally, an aging population is increasing, and aging is a natural physiological process and a major risk factor for all age-related diseases. It seriously threatens personal health and imposes a great economic burden. Therefore, there is a growing scientific interest in strategies for well-aging with prevention and treatment of age-related diseases. The seed, root, stem or leaves of Cassia tora Linn. are useful for anti-bacteria, anti-hyperlipidemia and anti-obesity due to its pharmacological activities such as anti-inflammation and anti-oxidant both in vitro and in vivo. Nevertheless, no clinical trials have been attempted so far, therefore here we would like to understand the current preclinical activities for aging-related disease models including cataract, metabolic dysfunction and neurodegeneration, then discuss their preparation for clinical trials and perspectives.

The complete chloroplast (cp) genome sequences of three Amaranthus species (Amaranthus hypochondriacus, A. cruentus and A. caudatus) were determined by next-generation sequencing. The cp genome sequences of A. hypochondriacus, A. cruentus and A. caudatus were 150,523, 150,757 and 150,523 bp in length, respectively, each containing 84 genes with identical contents and orders. Expansion or contraction of the inverted repeat region was not observed among the three Amaranthus species. The coding regions were highly conserved with 99.3% homology in nucleotide and amino acid sequences. Five genes – matK, accD, ndhJ, ccsA and ndhF – showed relatively high non-synonymous/synonymous values (Ka/Ks > 0.1). Sequence comparison identified two insertion/deletion (InDels) greater than 40 bp in length, and polymerase chain reaction markers that could amplify these InDel regions were applied to diverse Korean Genbank accessions, which could discriminate the three Amaranthus species. Phylogenetic analyses based on 62 protein-coding genes showed that the core Caryophyllales were monophyletic and Amaranthoideae formed a sister group with the Betoideae and Chenopodioideae clade. Comparing each homologous locus among the three Amaranthus species, identified eight regions with high Pi values (>0.03). Seven of these loci, except for rps19-trnH (GUG), were considered to be useful molecular markers for further phylogenetic studies.

The Sewol ferry disaster is one of the most tragic events in Korea’s modern history. Among the 476 people on board, which included Danwon High School students (324) and teachers (14), 304 passengers died in the disaster (295 recovered corpses and 9 missing) and 172 survived. Of the rescued survivors, 72 were attending Danwon High School, located in Ansan City, and residing in a residence nearby. Because the students were young, emotionally susceptible adolescents, both the government and the parents requested the students be grouped together at a single hospital capable of appropriate psychiatric care. Korea University Ansan Hospital was the logical choice, as the only third-tier university-grade hospital with the necessary faculty and facilities within the residential area of the families of the students. We report the experiences and the lessons learned from the processes of preparing for and managing the surviving young students as a community-based hospital. (Disaster Med Public Health Preparedness. 2017;11:389–393)

Three-dimensional (3D) data processing has applications in solving complex tasks such as object recognition, environment modeling, and robotic mapping and localization. Because using raw 3D data without preprocessing is very time-consuming, extraction of geometric features that describe the environment concisely is essential. In this sense, a plane can be a suitable geometric feature due to its simplicity of extraction and the abundance in indoor environments. This paper presents an online incremental plane extraction method using line segments for indoor environments. Our data collection system is based on a “nodding” laser scanner, so we exploit the incremental nature of its data acquisition in which physical rotation and 3D data processing are conducted in parallel. Line segments defined by two end points become supporting elements that comprise a plane, so a large proportion of scan points can be ignored once the line segments are extracted from each scan slice. This elimination of points reduces the algorithm complexity and computation time. Experiments with the tens of complete scan data sets which were acquired from a typical indoor environment demonstrated that our method was at least three times faster than the state-of-the-art methods.

The crystallization of amorphous silicon thin films by electron beam exposure was studied. Amorphous silicon and silicon dioxide layers were deposited on glass substrate by PECVD at 360 °C. The optimization to crystallize 300 nm thick amorphous silicon film was carried out at a RF power of 300 W, DC voltage of 1500 V, Argon gas flow rate of 3 sccm and a distance between electron beam mesh and sample of 40 mm. High quality nano-crystalline silicon films with an activation energy of 0.47 eV from conductivity, a grain size of 15–45 nm from SEM and Raman crystalline volume fraction of 93.1% were fabricated. We expect that e-beam exposure will be applied to crystallization of amorphous silicon films.

The hardness changes caused by formation of the metastable and stable phases were examined and correlated with the microstructural changes in grain interior and grain boundary during aging at 350 °C to clarify the age-hardening and softening mechanism of a low-gold Au-Cu-Ag-Pd dental alloy. Aging in this context refers to the time-delay that occurs wherein such alloys are kept at elevated temperatures for periods upto many hours to allow precipitation or ordering to take place. During the period of increasing hardness, the matrix was separated into the Ag-rich α1 and AuCu I phases through the metastable phases, forming block-like structure. The apparent hardening was attributed primarily to lattice strain due to the tetragonality of AuCu I′ [the primer (′) here indicates a metastable phase; likewise (I) and (I′) indicate stable AuCu I and metastable AuCu I′ phases, respectively] and AuCu I phases along the c-axis, secondarily to the coherency or semicoherency strain between the metastable α1′ and AuCu I′ phases and between the α0 and AuCu I phases along the a-axis. The apparent softening was caused primarily by growth and coarsening of the lamellar structure in the grain boundaries, secondarily by coarsening of the block-like structure in the grain interior.

(001) oriented (Ba, Sr)TiO3 (BST) thin films were deposited on MgO (001) single crystal substrates by the pulsed laser deposition method. Structural properties of BST films were investigated using X-ray diffractometer. Coplanar waveguide (CPW) device based on BST/MgO layer structure was fabricated by dc sputtering deposition, photolithography and etching process. To study the geometrical factor dependent microwave performance of the CPW phase shifter based on (001) oriented BST film, the CPW devices having various gap and width were fabricated. The microwave dielectric properties of BST CPW phase shifter devices were examined by calculating the scattering parameter obtained using a HP 8510C vector network analyzer with the frequency range 0.5 ∼ 20 GHz at room temperature under the dc bias field of 0 ∼ 40V. The measured return loss and insertion loss at 10 GHz with no dc bias were about -12 ∼ -4 dB and -14 ∼ -3 dB, respectively, which mainly depended on the impedances of the CPW transmission lines. The measured differential phase shift values were about 20 ° ∼ 140 ° at 10 GHz with 40 V dc bias variations, which depended on the gap size.

Surface acoustic wave (SAW) propagation properties of gallium nitride (GaN) epitaxial layers on sapphire were theoretically and experimentally characterized. GaN thin films were grown on a c-plane sapphire substrate using a metalorganic chemical vapor deposition system. The experimental characterization of SAW propagation properties was performed with a linear array of interdigital transducer structures, while SAW velocities were calculated by matrix methods. Experimentally, we found pseudo-SAW and high-velocity pseudo-SAW modes in the GaN/sapphire structure, which had a good agreement with calculated velocities.

Effect of SiO2 capping layer(C/L) on recrystallization of amorphous Si (a-Si) film was investigated. When a thick C/L over 500 Å was deposited on an a-Si film before crystallization, fine p-Si grains less than 100nm were obtained at full range of energy density window. However, when a thin C/L below 200 Å was used, Si-melt spouted out through C/L at over critical energy density. When Si-melt started spouting, abrupt change of grain size also occurred. These large grains could be explained by a non-uniformity of heat flow caused by Si-melt spouting. With this polycrystalline Si (p-Si) material having appreciable grain size protected by C/L, fabrication of low-cost Low Temperature Poly Si (LTPS) without additional cleaning of p-Si surface could be successfully developed.

Microwave properties of coplanar waveguide (CPW) transmission lines fabricated on high dielectric materials, such as ferroelectric Ba1−xSrxTiO3 films, are highly sensitive on the dimension and shape of electrodes. A small change in device dimension affects the total electrical length of the CPW, which may mislead the effective dielectric constant of the dielectric layer. Furthermore, extracting dielectric constant of high-k thin films from the measured microwave properties, such as S-parameters, is very difficult. The well known a modified conformal mapping method frequently exhibits an inconsistent dielectric constant for CPW on high-k materials. CPW transmission lines were fabricated on high-k thin films, ferroelectric Ba0.6Sr0.4TiO3, which were deposited by the pulsed laser deposition with partial oxygen backgrounds. A large phase shift angle of 100° at 10 GHz was observed from the CPW (gap = 4 μm, length = 3 mm) with a 40 V of dc bias, which supports that the idea of the tunable microwave device application using ferroelectrics films. The dielectric constant of the thin ferroelectric film was extracted from the dimension of the CPW (gap, width, length) and the measured S-parameters by a modified conformal mapping. However, the dielectric constant of the ferroelectric thin film calculated by a modified conformal mapping exhibits a gap dependency; dielectric constant (990 ∼ 830) decreases with increasing gap size (4 ∼ 19 μm, respectively). For comparison, dielectric properties have been extracted by extensive EM-simulation using a HFSS™ (Ansoft) with observed dimensions of CPW devices. Total phase, which is closely related with the dielectric constant of the film, is strongly affected by gap size, film thickness, and slanted angle of CPW.

An ultra-low temperature (< 200°C) polycrystalline silicon (poly-Si) film is fabricated for the plastic substrate application using inductively coupled plasma chemical vapor deposition (ICP-CVD) and excimer laser annealing. The precursor active layer is deposited using the SiH4/He mixture at 150°C (substrate). The deposited silicon film consists of crystalline component as well as hydrogenated amorphous component. The hydrogen content in the precursor layer is less than 5 at%. The grain size of the precursor active silicon film is about 200nm and it is increased up to 500nm after excimer laser irradiation.

We have studied infrared photoluminescence (PL) and x-ray diffraction (XRD) of 400 nm and 1500 nm thick InAs epilayers on GaAs, and 4 nm thick InAs on graded InGaAs layer with total thickness of 300 nm grown by molecular beam epitaxy. The PL peak positions of 400 nm, 1500 nm and 4 nm InAs epilayer measured at 10 K are blue-shifted from that of InAs bulk by 6.5, 4.5, and 6 meV, respectively, which can be largely explained by the residual strain in the epilayer. The residual strain caused by the lattice mismatch between InAs and GaAs or graded InGaAs/GaAs was observed from XRD measurements. While the PL peak position of 400 nm thick InAs layer is linearly shifted toward higher energy with increase in excitation intensity ranging from 10 to 140 mW, those of 4 nm InAs epilayer on InGaAs and 1500 nm InAs layer on GaAs is gradually blue-shifted and then, saturated above a power of 75 mW. These results suggest that adopting a graded InGaAs layer between InAs and GaAs can efficiently reduce the strain due to lattice mismatch in the structure of InAs/GaAs.