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Accurate measurement of microscale mass changes is crucial for various applications including toxic gas detection and medical diagnosis. Recent exploration in microelectromechanical systems (MEMS) has brought significant advancements in microscale sensing. Despite unprecedented sensing resolution, linear resonance-based MEMS sensors often require carefully controlled environment for operation due to unavoidable damping and noise. Nonlinear MEMS sensors exploiting large structural responses have shown enhanced robustness against noise and damping; yet, sophisticated preventative control is often required to extend their structural reliability. Recent investigations on nonlinear circuits and feedback controls have focused on detecting mass adsorption by indirectly introducing the essential nonlinearity. To overcome these challenges, this research presents a novel amplitude-based strategy for microscale mass sensing using an array of adaptive bistable circuits. A hybrid linear and bistable system is devised which utilizes linear cantilever-based resonators integrated with an array of adaptive bistable circuits for quantifying micro-mass adsorption at the linear cantilever beam tip by monitoring sudden and drastic response changes (bifurcation) in the bistable circuit array. The structural response is reflected into the piezoelectric voltage which is provided as an input to the bistable circuit array through the electromechanical coupling of piezoelectric transducer. The input amplitude is adjusted to be near the bifurcation thresholds of the bistable circuits, which are adaptively tuned by the gain of each circuits. The thresholds are distributed by four standard deviations of the bifurcation distribution, which determines the theoretical minimum sensing resolution with 95% probability given ambient noise level. The output levels of each circuit are evaluated whether they exhibit unmistakably different intra- or interwell responses that depend on the minute input voltage variations induced by mass adsorption. By comparing the array of results between the initial and mass-adsorbed states, we could accurately quantify the input amplitude change that linearly corresponds to the adsorbed mass. The proposed sensing approach utilizing bifurcation phenomena was verified by numerically simulating the integrated electromechanical system. A numerical case study under the presence of Gaussian white noise with 28 dB SNR is performed demonstrating that the proposed bifurcation-based approach shows 300% enhanced resolution compared to the conventional peak detection method. Experimental investigations conducted on a mesoscale proof-of-concept platform also verify the enhanced performance of the proposed approach. The proposed approach yields an added mass ratio of 9.8e−4, which shows more than 700% enhancement compared to that of the prior bifurcation-based detection results. Overall, numerical and experimental results verify that the proposed approach provides remarkably enhanced resolution compared to prior advancements, and suggest that the proposed strategy holds promise for various applications such as low-cost diagnostics and structural health monitoring, which require precise and accurate measurement. Future work will focus on applying the enhanced sensing capability of proposed strategy to linear MEMS resonators which are expected to yield higher resonance frequency and baseline mass sensitivity, for enhancing various applications in medical diagnosis, public health, and safety.

Advances in additive manufacturing technologies have shown that bio-additive manufacturing has opened a new frontier in the biomedical field for 3D printing human organs. Despite these advancements, it is significantly challenging to reliably identify damage features, especially embedded defects, using non-contact methods. This research devises a novel method that can reliably assess the damage characteristics without contact by using video-based vibrometry. Vibration signals provide an integrated response of the target structure including geometry changes such as defects in bioprinting. Since the phase shift of the pixel intensity is intrinsically related to any motion captured in the video, the vibration characteristics that reflect surface and embedded defects can be remotely assessed for the entire structure captured in the camera view from a distance without installing several sensors on the structure. In this study, the vibration characteristics of a cube that is manufactured by an extrusion-based bio-printer with pneumatic dispensing are experimentally obtained by using a high-speed camera and phase-based motion estimation technique. The occurrence of damage and its severity are identified by monitoring the change of the vibration characteristics. A finite element model was formulated, and its response characteristics are compared with the experimentally obtained results. Overall, the results of this study reveal promising potential of implementing video vibrometry for effectively verifying the structural integrity of additively manufactured organs after fabrication, which may be the foundational step in the quality testing of bioprints.

In spite of availability of several plastomes representing different tribes of Plantaginaceae, sparse attempts have been made to understand the plastome structure, evolution, and phylogenomics. In the present study, we have made an effort to understand the gene content and plastome evolution in the family Plantaginaceae using the newly generated plastome sequence of Veronica ovata subsp. kiusiana, a taxon native to SE Asia. In the first-ever attempt, plastomes of seven out of 10 tribes of Plantaginaceae have been compared to understand the evolution across the tribes of Plantaginaceae. The size of the plastome of V. ovata subsp. kiusiana is 152,249 bp, showing a typical quadripartite structure containing LSC, SSC, and two IRs with the sizes of 83,187, 17,704, and 25,679 respectively. The plastome comparison revealed the unique deletions in ycf2 and ndhF genes of members of different tribes, and also revealed high nucleotide variable hotspots. The study also revealed six highly variable genes and intergenic spacer viz. rps16, rps15-ycf1, ccsA-ndhD, ndhC-trnV, petN-psbM, and ycf1-trnN as potential DNA barcodes for the genus Veronica. The phylogenomic study revealed the sister relationship between V. ovata subsp. kiusiana and V. persica and also suggested the tentative placement of seven tribes in the family Plantaginaceae.

The aim of this study was to investigate the relationship between subdivision design and landscape structure. The study outcome reveals how street-related design elements influence landscape structure, especially patch size, which represents species diversity and species distribution. Comparison analysis was conducted between two areas that had similar pre-development ecological conditions but were developed with different design approaches: ecological design approach and conventional development approach. Aerial photos of each area were classified as forested or non-forested, and landscape structure was quantified with six landscape metrics related to fragmentation. The ecologically planned community, which is designed with lower lot perimeter, narrower street width, and fewer number of intersections showed a less fragmented forest pattern and resulted in more ecologically structured environments. This study also revealed street-related design metrics were more significantly related to habitat fragmentation than parcel-related metrics. This study provides quantified landscape configuration and composition, showing the influence of design metrics on landscape structure. Understanding how elements of design metrics affect ecological landscape patterning is important for landscape architects and planners for planning and designing ecologically healthy environments.

There is abundant evidence that green space in urban neighborhood is associated with physical activity and it is well known that physical activity contributes to human health. Physical activity fosters normal growth and development, can reduce the risk of chronic diseases, and can make people feel better and function better. Evidences also show that exposure to natural places can lead to positive mental health outcomes, whether a view of nature from a window, being within natural places, or exercising in these environments. The study aims to identify the factors of forest structure and socioeconomic characteristics influencing adults&rsquo, physical activity and health. A sample of 148,754 respondents from the Korea Community Health Survey, conducted in 2016, was analyzed. Measures included frequency of physical activity, stress, depression, and landscape metrics of forest patch. Hierarchical multiple regression analysis, controlling for socio-demographic characteristics, revealed that larger forest patches and the more irregular shapes were associated with more physical activity. The study also showed that the shape of forest patch and slope were associated with less mental health complaints, whereas composition related landscape metrics were not.

Recently, the green infrastructure (GI) concept has been adopted by many cities for stormwater management even though doubt still remains as to whether it can be fully embedded into planning and design. As many researchers have stated, GI planning has been discussed as offering a number of broad benefits in ecological, economic, and social spheres. The aim of this study is to examine the benefits of GI which can be used at various ranges of scale to support the principles of low impact development (LID). Case studies of two different scales, site scale and neighborhood scale, have shown ecological, social, and economic benefits of GI. The projects include GI elements and LID strategies such as green roof, rain barrels, porous pavement, rain garden, gravel grass, vegetated swales, and retention basins. The result indicates that GI elements are effective in detaining stormwater and reducing the amount of runoff. Native prairie grasses, sedges, and plantings also improved habitat value and led to a noticeable increase in birds, bees, and butterflies. The GI project provided outdoor activities, promoted social interaction, and showed a positive effect on economic spheres as well. Quantification of these benefits is important for landscape architects, planners, and policy makers because it can provide better strategies for GI planning.

This study aimed to classify damaged lands, to find what are the damage factors affecting the studied area, and to present a prescription in order to provide some benefit for the restoration of Regional Ecological Network at Chungnam province. Finally we classified damaged lands from 1st to 4th damaged lands according to relative intensity of damage. The main damage factors for the First Damage Lands were humus horizon, soil hardness and plant species richness. In the Second Damage Lands, those were soil hardness, plant species richness, number of plants and dominant plant species. In the Third Damage Lands, those were humus horizon, soil hardness, plant species richness, number of plants and dominant plant species. In the Fourth Damage Lands, those were humus horizon, organic matter, soil hardness, EC, T-N content, plant species richness, number of plants and dominant plant species. In every cases, the damage of soil and vegetation was originated due to development carried out by human being. The changes in soil condition were not big enough for it to affect plant growth, however, degradation of vegetation was still severe.

Forest practices for mountainous areas can enhance the scenery value and function of forests. However, forest scenery management is rarely implemented except for conservation areas and public forests. In this study, we first used the viewshed analysis to extract visible and invisible zones from the surface areas of ordinary mountains in Korea, and then we used spatial aesthetic analysis to interpret the human-recognized characteristics on the visible zones of mountain scenery. Finally, based on the results of both analyses, reasonable guidelines for forest practice planning were proposed to improve the scenery of ordinary mountains. The result shows that the viewshed analysis made it possible to extract visible and invisible areas from the surface areas of ordinary mountains, and to determine the scale of zoning for forest practices to improve mountain scenery. In addition, using spatial aesthetic analysis, it was possible to explain the characteristics of mountain scenery according to distance and elevational differences between viewpoint and target, and to suggest a treatment target and direction for forest practices to improve the mountain scenery. This study is meaningful in that the viewshed and spatial aesthetic analyses were applied to evaluate the current scenery of ordinary mountains and to present guidelines for forest practice planning to promote their own scenery values.

Easy access to green space and the presence of lush tree canopy in neighborhoods provide substantial psychophysical benefits to residents. However, these urban amenities are often unevenly distributed between white and racial/ethnic minority residents. In this study, we investigated racial/ethnic disparities in access to parks and tree canopy using a geographic information system (GIS) and remote-sensing techniques in six Illinois cities. An accessibility index based on a new Google Maps application programming interface (API) was used to calculate walking distances between points of origins and parks, and integrated classification techniques were applied to calculate the amount of tree canopy. Kernel-smoothing function was applied to both canopy and park layers to transform point value to continuous surface value. Both ordinary regression and spatial regression were used to find the relationship. The results of this study show that racial/ethnic minorities have less tree canopy in their neighborhoods, but it did not find significant differences in terms of access to parks. Spatial regression was determined to be an effective modeling approach for the data used in this study. Methods used in this study can be extended to study accessibility to various destinations using different means of transit, and the results can guide intervention programs to help reduce environmental inequity.

The purpose of this study is to investigate the relationship among landscape structure, zoning ordinance, and geographic attributes in Morgantown, West Virginia. Two residential areas zoned by different standards, but with similar development history and socioeconomic status were examined. Aerial photography was digitized into woody and non-woody areas and the landscape structure was quantified with six core landscape metrics related to fragmentation. Computer aided design (CAD) map and digital elevation model (DEM) were used for the calculation of building footprint and geographical characteristics respectively. The findings indicate that differences in zoning requirements result in distinct landscape structure. Zoning requirements for smaller minimum lot size and lot frontage result in more vegetation but also result in more fragmentation than requirements that call for greater minimum lot size and lot frontage. Although building footprint is weakly associated with landscape structure, lot size and lot perimeter are strongly related to vegetation abundance, fragmentation, and dominance. Slope is associated with vegetation patch size, especially in hilly residential neighborhoods. This study provides a better understanding of how human and environmental factors are related to residential landscape structure at different scale. Providing numerous quantitative metrics is useful for understanding social and ecological benefits. The results of this study will help planners, landscape architects, and administrators for planning and designing more ecologically and socially sustainable neighborhoods.

The aims of this study were to investigate the relationship between ecological landscape structure and local development regulations over time. Comparison analysis was conducted between two areas that had similar pre-development ecological conditions but were developed under vastly different regulatory environments. The Woodlands (regulated to protect ecological condition) and the North Houston area (which followed traditional subdivision regulations) were examined at three different developmental time periods: pre-development, early development (after 10 years), and matured development (after 30 years). Aerial photos of each site from the three time periods were classified into forested and non-forested classes and the landscape structure was quantified with a number of landscape metrics related to fragmentation – an indicator of habitat degradation. Two factors, the ecological approach to landscape planning and the adoption of more restrictive landscape regulations and guidelines, are discussed on the premise that they exert influence in developing and maintaining the long-term sustainability of ecosystems. This study provides quantified landscape configuration and composition of the effects of development regulations on landscape structure. The ecologically planned community shows that a less fragmented forest pattern and more restrictive development guidelines result in more ecologically structured environments. Understanding how elements of local development regulations affect ecological landscape patterns is important for landscape architects, planners, and administrators because it can lead to better strategies for planning and designing sustainable communities.

We use a bivariate generalized autoregressive conditionally heteroskedastic (GARCH) model of inflation and output growth to examine the causality relationship among nominal uncertainty, real uncertainty and macroeconomic performance measured by the inflation and output growth rates. The application of the constant conditional correlation GARCH(1,1) model leads to a number of interesting conclusions. First, inflation does cause negative welfare effects, both directly and indirectly, i.e. via the inflation uncertainty channel. Secondly, in some countries, more inflation uncertainty provides an incentive to Central Banks to surprise the public by raising inflation unexpectedly. Thirdly, in contrast to the assumptions of some macroeconomic models, business cycle variability and the rate of economic growth are related. More variability in the business cycle leads to more output growth.

The purpose of this paper is to provide a comprehensive methodology for the analysis of the Asymmetric Power ARCH model. First, it gives the ARMA representations of a power transformation of the conditional variance and the absolute returns. Second, it derives a certain fractional moment of the absolute observations. Third, it obtains the autocorrelation function of the power-transformed absolute returns. Finally, the practical implications of the results are illustrated empirically using daily data on five East Asia stock indices. D 2005 Elsevier B.V. All rights reserved.

Using a bivariate GARCH model of inflation and output growth we find evidence that higher inflation and more inflation uncertainty lead to lower output growth in the Japanese economy. These results support the argument of a price stability objective for the monetary authority.

Green Infrastructure (GI) can be used as a framework for planning human settlements and guiding development away from natural areas that possess high ecological value and provide important Ecosystem Services for society’s development. In this paper, we present a GI Plan for Yesan County (Yesan GI Plan), a small shrinking city in the Republic of Korea. Yesan possesses very rich, but still fairly unexplored natural and cultural resources. Therefore, Yesan’s GI Plan was developed through a multifunctional approach based on the different ecological and socio-cultural characteristics of the region, allowing to connect the core elements that conform the vernacular landscape and get the most out of the Ecosystem Services provided by resources in the area. The plan was defined mainly in two stages: first, applying weights to the different ecological and socio/cultural characteristics; secondly, arranging them through a set of GIS spatial analysis tools using a patch-corridor- matrix model approach. The final outcome is a lean network of ecological value hubs, connected to a set of socio-cultural value assets through a network of water bodies, intrinsic forestry characteristics and wildlife mobility in the area. This was followed in order to connect, facilitate and improve mobility and energy flow in Yesan.

A new bioactive compound, namely desmodianone H (1), and another known compound uncinanone B (2) were first isolated using bioactivity-guided isolation from the leaves of Lespedeza maximowiczii and structures were elucidated by comprehensive analysis of their nuclear magnetic resonance and mass spectrometry data. Compounds 1 and 2 exhibited strong inhibitory effects on mushroom tyrosinase activity.