Airborne Measurements of High Pollutant Concentration Events in the Free Troposphere over the West Coast of South Korea between 1997 and 2011

Aircrafts enable the direct measurement of chemical components in the free troposphere (FT). This study employed airborne measurements to examine the occurrences of high concentrations of SO2 and NOx in the FT over the coastal region west of the Seoul metropolitan area, South Korea. The data from a long-term (1997-2011) airborne measurement campaign were used to determine the meteorological conditions favorable for carrying these pollutants into the Seoul area. The back trajectory analyses of 21 instances of high FT pollutant concentration events showed ascending patterns from the major pollutant sources, mainly the industrial complexes in eastern China, in 9 instances and passing patterns in 12 instances. In the ascending instances, developing low-pressure systems over the source regions provide favorable conditions to uplift air pollutants from the surface into the FT. In the passing instances, an anomalous low-pressure system near the surface prevented airflows from descending into the boundary layer and upper-level anticyclonic systems helped to keep the ascending airflows in the FT. This study proposes the basic mechanisms for predicting air quality in the Seoul area, considering that air pollutants in the FT often entrain into the boundary layer to increase local concentrationsopen0

Industrialisasi Berbasis Pertanian sebagai Grand Stratedy Pembangunan Ekonomi Nasional

EnglishAs a developing economy Indonesia, should have a comprehensive integrated long-term development plan which may be used as the guideline in implementing its national economic development as well as an instrument for evaluating government accountability and credibility. The New Order regime had prepared its first and second long-term development plan for 1969-1993 and 1993-2018 successively. The twin plans, however, has led Indonesia to the 1997-1999 multi dimensions crises and is considered in appropriate in the existing new era of total reformation. It must be totally reconstructed. For this, public discussions on the need for the government to formulated the new grand strategy of national development have emerged, but up and down, in the last two years. As an active contribution to the public debase, this paper reviews previous, Indonesia development plans, others\u27 countries experiences as well as grand theories of economic development. Then it is suggested that the agricultural based industrialization may be the most suitable one for Indonesia. The new grand strategy should be decided based on a national concensus in order to avoid the practice of just for political rhetoric\u27s as was during the New Order regime. IndonesianBagi negara berkembang seperti Indonesia, rencana pembangunan jangka panjang komprehensif-integratif sangat di perlukan sebagai acuan pelaksanaan pembangunan dan sebagai salah satu instrumen akuntabilitas dan kredibilitas pemerintah. Pemerintahaan Orde Baru telah menyusun rancangan pembangunan jangka panjang tahap I dan II masing-masing untuk peiode 1969-1993 dan 1993-2018. Rencana jangka panjang yang disusun rejim Orde Baru tersebut terbukti membawa Indonesia kedalam krisis tahun 1997-1999 dan sudah tidak sesuai dalam era Reformasi sehingga perlu dirancang ulang. Dalam dua tahun terakhir sesungguhnya telah muncul wacana publik yang menuntut agar pemerintah segera menyusun grand strategy ( strategi besar ) pembangunan nasional. Sebagai bagian dari wacana tersebut, tulisan ini mereview tentang konsepsi strategi pembangunan selama Orde Baru, pengalaman beberapa negara lain pemikiran teoritis tentang strategi pembangunan ekonomi. Berdasarkan hasil review tersebut, disarankan agar industrialisasi berbasis pertanian (agricultural based industrialization) dijadikan sebagai strategi besar (grand strategy) pembangunan nasional. Strategi tersebut haruslah dijadikan sebagai konsensus nasional, sehingga tidak sekedar retorika politik seperti pada masa Orde Baru

A 23μW Solar-Powered Keyword-Spotting ASIC with Ring-Oscillator-Based Time-Domain Feature Extraction

Voice-controlled interfaces on acoustic Internet-of-Things (IoT) sensor nodes and mobile devices require integrated low-power always-on wake-up functions such as Voice Activity Detection (VAD) and Keyword Spotting (KWS) to ensure longer battery life. Most VAD and KWS ICs focused on reducing the power of the feature extractor (FEx) as it is the most power-hungry building block. A serial Fast Fourier Transform (FFT)-based KWS chip [1] achieved 510nW; however, it suffered from a high 64ms latency and was limited to detection of only 1-to-4 keywords (2-to-5 classes). Although the analog FEx [2]–[3] for VAD/KWS reported 0.2μW-to-1 μW and 10ms-to-100ms latency, neither demonstrated >5 classes in keyword detection. In addition, their voltage-domain implementations cannot benefit from process scaling because the low supply voltage reduces signal swing; and the degradation of intrinsic gain forces transistors to have larger lengths and poor linearity

Organic flexible memristor with reduced operating voltage and high stability by interfacial control of conductive filament growth

This work was supported in part through the BK21 Program funded by Ministry of Education of Korea.Herein, the underlying mechanisms for the growth of conductive filaments (CFs) at a metal–polymer electrolyte interface through ion migration in organic electrochemical metallization (ECM) memristor are presented. It is observed that the free volume of voids (nanopores) in the polymer electrolyte serves as the pathways of metal‐cations whereas the interfacial topography between an active electrode and a polymer electrolyte determines the nucleation sites of the CFs. The growth kinetics of the CFs and the resultant resistive memory are found to vary with the molecular weight of the polymer electrolyte and the metal protrusions at the interface. Our direct observations show that the free volume of voids of the polymer electrolyte, varied with the molecular weight, dictates the ion transport for the growth and the disruption of the CFs. Our organic ECM‐based memristor with a hetero‐electrolyte exhibits high mechanical flexibility, low switching voltages reduced by about three times compared to those of conventional devices, and stable memory retention for longer than 104 s under repeated cycles of bending.PostprintPeer reviewe

Topography-Guided Spreading and Drying of 6,13-bis(triisopropylsilylethynyl)-pentacene Solution on a Polymer Insulator for the Field-Effect Mobility Enhancement

We report on the enhancement of the field-effect mobility of solution-processed 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene) by unidirectional topography (UT) of an inkjet-printed polymer insulator. The UT leads to anisotropic spreading and drying of the TIPS-pentacene droplet and enables to spontaneously develop the ordered structures during the solvent evaporation. The mobility of the UT-dictated TIPS-pentacene film (0.202 ± 0.012 cm2/Vs) is found to increase by more than a factor of two compared to that of the isotropic case (0.090 ± 0.032 cm2/Vs). The structural arrangement of the TIPS-pentacene molecules in relation to the mobility enhancement is described within an anisotropic wetting formalism. Our UT-based approach to the mobility enhancement is easily applicable to different classes of soluble organic field-effect transistors by adjusting the geometrical parameters such as the height, the width, and the periodicity of the UT of an inkjet-printed insulator

Thermally modulated multilayered graphene oxide for hydrogen storage

We have obtained high pressure H(2) isotherms with respect to the interlayer distance of multilayered graphene oxide (GO) modulated by thermal annealing. The maximum storage capacity is 4.8 (0.5) wt% at 77 K (298 K) and at 9.0 MPa pressure. We found the optimum GO interlayer distance for maximum H2 uptake at 6.5 angstrom, similar to the predicted distances from first-principles calculations for graphite materials. Our results reveal that multilayered GO can be a practical material of choice to allow the use of graphene as a hydrogen storage material, provided that only small amounts of O and OH functional groups exist as spacers on GO sheets.close171