The study of PM
and NO
has been emphasized in recent years due to their adverse effects on public health. To better understand these pollutants, many studies have researched the spatiotemporal ...distribution, trend, forecast, or influencing factors of these pollutants. However, rarely studies have combined these to generate a more holistic understanding that can be used to assess air pollution and implement more effective strategies. In this study, we analyze the spatiotemporal distribution, trend, forecast, and factors influencing PM
and NO
in Nagasaki Prefecture by using ordinary kriging, pearson's correlation, random forest, mann-kendall, auto-regressive integrated moving average and error trend and seasonal models. The results indicated that PM
, due to its long-range transport properties, has a more substantial spatiotemporal variation and affects larger areas in comparison to NO
, which is a local pollutant. Despite tri-national efforts, local regulations and legislation have been effective in reducing NO
concentration but less effective in reducing PM
. This multi-method approach provides a holistic understanding of PM
and NO
pollution in Nagasaki prefecture, which can aid in implementing more effective pollution management strategies. It can also be implemented in other regions where studies have only focused on one of the aspects of air pollution and where a holistic understanding of air pollution is lacking.
Recently, bivalves have been massively killed by anoxia or hypoxia in summer at the northern part of Isahaya Bay, Japan, which constituted a major problem for fisheries. However, the mechanism behind ...the occurrence of hypoxic water masses is unclear. It is known that the bottom water dissolved oxygen (DO) in this area is affected by the inflow of seawater into the northern mouth of Isahaya Bay. To understand the mechanism of hypoxia, it is necessary to determine the physical processes that cause changes in the bottom DO concentrations in this area. This study shows that there is a neap-spring tidal variation in bottom DO due to a change in vertical tidal mixing, and it also suggests that the decrease in bottom DO was generated by a baroclinic flow, which is due to the internal tide, and a shear flow, which is induced by the external tide in the bottom boundary layer. In addition, our study suggests that the source of cold and hypoxic water that appears in the bottom layer at low tide is the inner area of the Ariake Sea.
We investigated the effects of gate bias regarding the degradation of electrical characteristics during gamma irradiation. Moreover, we observed the punch through failure of 1.2 kV rated commercial ...Silicon Carbide (SiC) Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) due to the influence of gate bias. In addition, the threshold voltage (V
) and on-resistance (R
) of the SiC MOSFETs decreased significantly by the influence of gate bias during gamma irradiation. We extracted the concentration of carriers and fixed charge (Q
) in oxide using N-type SiC MOS capacitors and Transmission Line Measurement (TLM) patterns to analyze the effects of gamma irradiation. The Total Ionizing Dose (TID) effect caused by high-energy gamma-ray irradiation resulted in an increase in the concentration of holes and Q
in both SiC and oxide. To analyze the phenomenon for increment of hole concentration in the device under gate bias, we extracted the subthreshold swing of SiC MOSFETs and verified the origin of TID effects accelerated by the gate bias. The Q
and doping concentration of p-well values extracted from the experiments were used in TCAD simulations (version 2022.03) of the planar SiC MOSFET. As a result of analyzing the energy band diagram at the channel region of 1.2 kV SiC MOSFETs, it was verified that punch-through can occur in 1.2 kV SiC MOSFETs when the gate bias is applied, as the TID effect is accelerated by the gate bias.
Harmful cyanobacterial blooms are continuously formed in water systems such as reservoirs and lakes around the world. Geosmin and 2-methylisoborneol (2-MIB) produced by some species of cyanobacteria ...have caused odor problems in the drinking water of the Sanbe Reservoir in Japan. Field observations were conducted for four years (2015–2019) to investigate the cause of this musty odor. It was found that geosmin was produced by Dolichospermum crassum and Dolichospermum planctonicum (cyanobacteria), and 2-MIB was due to Pseudanabaena sp. and Aphanizomenon cf. flos-aquae (cyanobacteria). Changes in water temperature and pH caused by rainfall were correlated with changes in the concentration of geosmin and 2-MIB. In particular, geosmin and 2-MIB tended to occur under low rainfall conditions. When there was low rainfall, the reservoir changed to an alkaline state because the phytoplankton consumed CO2 for photosynthesis. In an alkaline reservoir, dissolved inorganic carbon mainly existed in the form of bicarbonate (HCO3−). Thus, the results suggest that under such conditions in reservoirs, cyanobacteria grew easily because they could use both CO2 and HCO3− for photosynthesis. Specifically, our study suggests that in order for the musty odor problem in the reservoir to be solved, it is important that the pH of the reservoir be controlled.
Simpson's stratification index φ is widely used in oceanography as an index of vertical stratification. However, the use of φ can be problematic when the tidal amplitude is significant compared to ...the water depth, since φ fluctuates periodically with the external tide even if the vertical density structure does not change. The stratification potential-energy anomaly V is proportional to the square of the water column thickness D; therefore, V∗=(H/D)2V (where H is the mean water depth) is an appropriate standardized stratification index for estuaries and regions of freshwater influence. The usefulness of this index is demonstrated using time series fk=H/DkVk=0,1,2,3(f0=V,f1=Hφ,f2=V*) and their power spectra as obtained from tower B3 in Isahaya Bay in Japan. Tidal cycle fluctuation is removed most effectively for f2(=V∗).
•A new stratification index that does not depend on the tidal level is proposed.•This index is the standardized potential-energy anomaly with respect to water column thickness.•This index is useful in areas where the tidal amplitude is not negligible.
Many edge/mobile devices are now able to utilize deep neural networks (DNNs) thanks to the development of mobile DNN accelerators. Mobile DNN accelerators overcame the problems of limited computing ...resources and battery capacity by realizing energy-efficient inference. However, its passive behavior makes it difficult for DNN to provide active customization for individual users or its service environment. The importance of on-chip training is rising more and more to provide active interaction between DNN processors and ever-changing surroundings or conditions. Despite its advantages, the DNN training has more constraints than the inference such that it was considered impractical to be realized on mobile/edge devices. Recently, there are many trials to realize mobile DNN training, and a number of prior works will be summarized. Firstly, it arranges the new challenges of the DNN accelerator induced by training functionality and discusses new hardware features related to the challenges. Secondly, it explains algorithm-hardware co-optimization methods and explains why it becomes mainstream in mobile DNN training research. Thirdly, it compares the main differences between the conventional inference accelerators and recent training processors. Finally, the conclusion is made by proposing the future directions of the DNN training processor in micro-AI systems.
An energy-efficient deep neural network (DNN) accelerator, unified neural processing unit (UNPU), is proposed for mobile deep learning applications. The UNPU can support both convolutional layers ...(CLs) and recurrent or fully connected layers (FCLs) to support versatile workload combinations to accelerate various mobile deep learning applications. In addition, the UNPU is the first DNN accelerator ASIC that can support fully variable weight bit precision from 1 to 16 bit. It enables the UNPU to operate on the accuracy-energy optimal point. Moreover, the lookup table (LUT)-based bit-serial processing element (LBPE) in the UNPU achieves the energy consumption reduction compared to the conventional fixed-point multiply-and-accumulate (MAC) array by 23.1%, 27.2%, 41%, and 53.6% for the 16-, 8-, 4-, and 1-bit weight precision, respectively. Besides the energy efficiency improvement, the unified DNN core architecture of the UNPU improves the peak performance for CL by 1.15<inline-formula> <tex-math notation="LaTeX">\times </tex-math></inline-formula> compared to the previous work. It makes the UNPU operate on the lower voltage and frequency for the given DNN to increase energy efficiency. The UNPU is implemented in 65-nm CMOS technology and occupies the <inline-formula> <tex-math notation="LaTeX">4 \times 4 </tex-math></inline-formula> mm 2 die area. The UNPU can operates from 0.63- to 1.1-V supply voltage with maximum frequency of 200 MHz. The UNPU has peak performance of 345.6 GOPS for 16-bit weight precision and 7372 GOPS for 1-bit weight precision. The wide operating range of UNPU makes the UNPU achieve the power efficiency of 3.08 TOPS/W for 16-bit weight precision and 50.6 TOPS/W for 1-bit weight precision. The functionality of the UNPU is successfully demonstrated on the verification system using ImageNet deep CNN (VGG-16).
This article presents a low-power, low-distortion, and compact mixed-signal sinusoidal current generator (CG) IC for bio-impedance (Bio-Z) sensing applications. By utilizing the digital ...<inline-formula> <tex-math notation="LaTeX">\Delta \Sigma </tex-math></inline-formula> modulation to bridge the digitally synthesized sinewave data and the analog-domain voltage output, implementation of a low-distortion sinewave lookup table (LUT) is significantly simplified. Not only does this approach lead to the reduced number of routing wires, pin allocation, and output registers after logic synthesis but also, it allows the use of dynamic element matching (DEM) with a low-cost, before interfacing with the digital-to-analog converter (DAC). In addition, 0.5 V of low-supply voltage exploits a highly power-efficient operation for both synthesized digital logic and its subsequent analog circuit chain. To suppress the noise-floor increase that is induced from the reset signal of capacitor-DAC, a half-period reset scheme is introduced. The prototype chip is fabricated in 65-nm CMOS technology and it outputs <inline-formula> <tex-math notation="LaTeX">2~\mu \text{A}_{\text {PP}} </tex-math></inline-formula> of amplitude with 20 kHz of sinusoidal frequency. It records the first sinusoidal CG IC that achieves sub-<inline-formula> <tex-math notation="LaTeX">10~\mu \text{W} </tex-math></inline-formula> (<inline-formula> <tex-math notation="LaTeX">6.2~\mu \text{W} </tex-math></inline-formula>) of power consumption and sub-0.1% (0.088%) of total harmonic distortion (THD) at the same time which has not been demonstrated ever in the prior arts. Furthermore, 0.059 mm 2 of its compact area facilitates the low-cost production of Bio-Z sensor systems.
The world is experiencing a global restructuring that poses a serious threat to international efforts to prevent and protect against torture. The rise of powerful transnational non-state actors such ...as gangs, drug cartels, militias, and terrorist organizations is challenging states' authority to control and govern torture committed within their territory. In the United States, those seeking protection against deportation under the Convention Against Torture ("CAT") must establish a likelihood of torture at the instigation of or by consent or acquiescence of a public official acting in an official capacity or other person acting in an official capacity. However, what is meant by "other person acting in an official capacity" such that torturous acts by non-state actors fall under U.N. Torture Convention protection remains unclear under U.S. CAT jurisprudence. While many aspects of the CAT have been litigated, clarified, and developed through case law since the United States ratified the CAT, the question of whether and when a non-state actor can be deemed an "other person acting in an official capacity" under the CAT within U.S. jurisprudence lacks scholarship or case law. We make the novel argument that courts and agencies should apply factors employed in civil rights claims (also known as § 1983 claims) to assess whether a non-state actor can act in an official capacity or under color of law. Doing so will help fill a critical gap in U.S. CAT protections.
Brackish waters and estuaries at the lower reaches of rivers accumulate organic matter and nutrients from various sources in the watershed. Sufficient light and shallow water depth stimulate ...phytoplankton growth, resulting in a more diversified ecosystem with higher trophic levels. For effective watershed management, it is crucial to characterize the water quality of all rivers, including small and medium-sized ones. Our field survey assessed water quality parameters in 26 inflow rivers surrounding Lakes Shinji and Nakaumi, two consolidated brackish lakes in Japan. The parameters included water temperature, salinity, chlorophyll-
a
, and nutrients. The study used hierarchical clustering. The Silhouette Index was used to assess clustering outcomes and identify any difficulties in dispersion across clusters. The 26 rivers surrounding Lakes Shinji and Nakaumi were classified into six groups based on their water quality characteristics. This classification distinguishes itself from earlier subjective methods that relied on geographical factors. The new approach identifies a need for improved management of river water quality. The results of the cluster analysis provide valuable insights for future management initiatives. It is important to consider these findings alongside established watershed criteria.
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