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This paper presents a charge-domain in-memory computing (IMC) macro for precision-scalable deep neural network accelerators. The proposed Dual-SRAM cell structure with coupling capacitors enables charge-domain multiply and accumulate (MAC) operation with variable-precision signed weights. Unlike prior charge-domain IMC macros that only support binary neural networks or digitally compute weighted sums for MAC operation with multi-bit weights, the proposed macro implements analog weighted sums for energy-efficient bit-scalable MAC operations with a novel series-coupled merging scheme. A test chip with a 16-kb SRAM macro is fabricated in 28-nm FDSOI process, and the measured macro throughput is 125.2-876.5 GOPS for weight bit-precision varying from 2 to 8. The macro also achieves energy efficiency ranging from 18.4 TOPS/W for 8–b weight to 119.2 TOPS/W for 2-b weight.

In our previous study, we verified that a two-step process was superior to the one-pot process for the manufacture of THTCPD, assuming the pilot-scale production aspect of a comparative economic analysis by using an engineering estimation method to predict the unit manufacturing cost. Among the processes of the two-step process, our study was intended to focus on the isomerization to produce the final THTCPD products with outstanding physical properties including a specific gravity, a heat of combustion, a viscosity and a freezing point. Although HY(30) was used as an isomerization catalyst in the previous study, the catalytic activity of HY(30) did not surpass that of AlCl3 in terms of isomerization conversion, possibly due to lower exo-THTCPD selectivity by Bronsted acid sites of HY(30) than that by Lewis acid sites of AlCl3. However, AlCl3 has some drawbacks of the impossibility for the catalyst regeneration during the manufacturing process due to the difficulty of the catalyst separation and recovery after isomerization, which causes environmental problems and biological toxicity issues due to its corrosivity. Therefore, our study concentrated on catalyst regeneration assuming the real production process in a pilot scale using AlCl3 in comparison with HY(30). Then, we investigated whether the isomerization catalyst AlCl3 or HY(30) was more commercially favorable through a comparative unit production cost prediction applying an engineering estimation in this study. In conclusion, the unit production cost for AlCl3 was lower than that for HY(30) with the fresh catalyst. Reversely, unit production costs for HY(30) with increase in catalysts regeneration number (N) were lower than those for AlCl3 due to the drastic decrease in the unit material cost of HY(30) unlikely with that of AlCl3 due to its non-reusability.

A charge-domain SRAM-based CIM macro is proposed to implement efficient neural accelerator with variable input/weight/output precisions. A versatile All-Around-Wire-Capacitor (AAWC) is introduced to enable accurate charge-domain MAV operation with 1-5 bit variable-precision weight capability with 10T SRAM cell structure. The AAWC also allows variable-precision array-embedded 1-5 bit digital-to-analog (DA) conversion for input, and 1-6 bit analog-to-digital (AD) conversion for output without additional passive devices. Such array-embedded DA/AD conversion scheme significantly reduces area overhead and simplifies peripheral circuits to achieve high array efficiency while achieving high energy efficiency of 24-330 TOPS/W.

Agricultural reclaimed land in Korea is increasingly being used for horticulture, grains, livestock, etc. However, soil of reclaimed land located in coastal lowland have so high salinity, poor fertility, high possibility of pollution that farming is difficult. Therefore, it is needed to promote desalination and fertility of soil and to reduce environmental burden through natural circulation farming. Therefore, we presented sustainable eco-friendly natural circulation model of agricultural resources in reclaimed land. The test complex was planned to apply circulation of energy and resources between horticulture and livestock focusing on Hanwoo, Korean-bred cattle. After comparing and analyzing the pH, organic matter, effective phosphate, potassium, calcium, magnesium, and electrical conductivity of the reclaimed land soils, and the general range soils, the appropriate number of Korean cattle was calculated. The estimated livestock manure of Korean cattle is used for liquid fertilizer, composting and energy. The total manure discharge can be calculated according to the area from one manure discharge. In addition, Pellet from cattle's manure was planned to be fueled and used as heating energy for horticulture facility. The greenhouse can be sized to a scale that meets the greenhouse's total heating load by calculating the total amount of energy generated from the manure. Therefore, plastic greenhouse-type horticultural complexes and livestock complexes including fuel facility using manure pellet are planned. So, natural circulation is completed as the manure of livestock provides the organic matter to the farmland and heating energy to the greenhouse. Additionally, agricultural product processing, sales and distribution centers, themed landscape agricultural complexes, ecological parks, agricultural tourism facilities, and observation facilities were arranged.

Reclaimed land in Korea is increasingly being used for horticulture, grains, livestock, etc. However, soil reclaimed land located in coastal lowland have so high salinity, poor fertility, high possibility of pollution that farming is difficult. Therefore, it is needed to reduce environmental burden and to promote fertility of soil through natural circulation farming. Therefore, we presented sustainable eco-friendly natural circulation model of agricultural resources in reclaimed land. It promotes desalination and fertility of soil through eco-friendly circular farming by integrating horticulture and livestock. To demonstrate the model, the test complex is planned to apply energy and resources circulation between horticulture and livestock focusing on Hanwoo, Korean-bred cattle. Basically high-technical plastic greenhouse-type horticultural complexes and livestock complexes including fuel facility using manure pellet are planned. Additionally, agricultural product processing, sales and distribution centers, themed landscape agricultural complexes, ecological parks, agricultural tourism facilities, and observation facilities were arranged.

A highly ordered mesoporous aluminosilicate (MMZY) was prepared by a top-down and bottom-up method using HY zeolite as a raw material. A pellet-type catalyst was prepared through extrusion using a twin-screw extruder. The effects of the Si/Al2 ratio of the HY zeolite used in the MMZY catalyst preparation on the physicochemical and acid properties of MMZY catalysts were investigated. The oligomerization of endo-dicyclopentadiene (endo-DCPD) was performed in a spinning basket reactor, and the deactivated catalyst was repeatedly regenerated to verify the possibility of reusing the catalyst. It was confirmed that ordered hexagonal arrays of mesopores were well developed in the MMZY(27) and MMZY(48) catalysts, whereas the mesoporous structure of the MMZY(6) and MMZY(12) materials with relatively large amounts of Al collapsed. As the Si/Al2 molar ratio of the MMZY catalyst was increased, the number of weak acid sites increased prominently and the acid strength decreased. MMZY(27) and MMZY(48) are more effective for the oligomerization of endo-DCPD to exo-tricyclopentadiene (exo-TCPD) compared to a microporous HY catalyst. This is attributed to the abundant acid sites and to the well-developed mesopore structure. Calcination in air was found to be effective for the regeneration of the deactivated MMZY pellet catalyst for synthesis of exo- TCPD from endo-DCPD.

Large areas of reclaimed land have recently been required to be developed as environmentally friendly centers of vegetation, such as dryland fields for cultivation of high-income crops and green fields. However, reclaimed lands in coastal areas such as reclaimed tidal flats have a setback in this regard: The capillary rise of groundwater from deeper levels causes resalinization, resulting in concentration of salt at the surface. The existing studies conducted on resalinization of soils in reclaimed lands are either insufficient or employ complex experimental and analytical methods. In this study, resalinization testing equipment was developed, and a laboratory model test on reclaimed-land soil was carried out. We identified the relationship between the capillary rise rate and initial volumetric water content and proposed a simple experimental model. The proposed model was verified by a comparison with experiment results and measured data of the field and could more accurately predict the resalinization according to the volumetric water content. In addition, proposed model can be applied in the field as the predicted results showed a similar trend to that of the measurements of the field.

For the studies on moving object databases, we need moving object trajectory data sets. For example, a benchmark data set of moving object trajectories is required for experiments on query processing of moving object databases. For these reasons, several tools have been developed for generating moving objects in Euclidean spaces or road network spaces. Indoor space differs from outdoor spaces in many aspects and moving object generator for indoor space should reflect these differences. In this paper, we present a moving object generation tool for indoor space. First, this tool generates trajectories for pedestrians in an indoor space. And it provides a parametric generation of trajectories considering not only speed, number of pedestrians, minimum distance between pedestrians but also type of spaces, time constraints, and type of pedestrians. We try to reflect the patterns of pedestrians in indoor space as realistic as possible. For the reason of inter-operability, several geospatial standards are used in the development of the tool.