In this paper, a study on the development and verification of flight control algorithms for a Lift-Cruise tandem-wing vertical takeoff and landing (VTOL) unmanned aerial vehicle equipped with the open-source flight control software PX4 was conducted. PX4 provides guidance, navigation, and control algorithms suitable for various UAV configurations. However, the provided algorithms are primarily designed for small size and typical vehicles with high thrust-to-weight ratios and low wing loading, In contrast, the developed UAV has characteristics of high wing loading and slow flight control response because the vehicle is relatively faster and heavier with its maximum take-off weight of 50kg. Considering these features, the open-source PX4 algorithms should be modified to apply to the vehicle flight control system, especially on the attitude control logic for multicopter-to-fixed wing transition. The modified control logic and algorithms were implemented and evaluated using a simulation which integrated a dynamic model in MATLAB/Simulink with SITL (Software-in-the-Loop) in PX4. The effectiveness of the modified flight control logic was verified through real flight tests.

This paper discusses the utilization of fault-tolerant technology in the industry by analyzing the status of drone failures in the unmanned vehicle industry survey conducted in 2020. Based on the survey results of the domestic unmanned vehicle industry, we identify subsystems with high fault rates and high severity when faults occur. In addition, fault simulations of the identified subsystems are conducted to analyze the effect of the fault on the vehicles. After that, the fault diagnosis and fault compensation methods studied so far are reviewed, and research cases of the methods are examined. Moreover, the ways to apply it to actual fault cases in the unmanned vehicle industry are debated. Furthermore, based on the previous discussion, the fault-tolerant system is presented, and the consideration when designing the fault-tolerant system in the industry are studied.

Public Procurement for Innovation (PPI) facilitates making new market in the public sector with the government procuring power [1] [2]. In order to make initial market for public service, the R&D program of MSIT is being advanced collaborated with the PPI process of PPS. In this paper, I introduced the small drone development program for PPI in Korea and explained the process and results of each stage.

A structural weight estimation methodology for the multicopter design process is presented. In general, a multicopter is composed of an airframe, motors, propellers, battery and so on. Among these, the weight of motors, propellers and battery can be obtained from the weight trends with respect to design parameters. However, the structural weight is hard to be estimated due to the various configurations and design concepts of multicopters. Moreover, the airframe weights of most commercial multicopter products are not provided. Thus, an accurate airframe weight model is required for the reliable mutlcopter design process. Firstly, the standard configuration of multicopters is defined. Then, we proposed the structural weight estimation method using the number and diameter of propellers determined from the initial step of sizing process. Finally, we validated our suggested method using the commerical products.

Polygonum multiflorum is a medicinal plant with strong antioxidant, anti-inflammatory, and cholesterol-lowering effects. We sought to improve the effectiveness of its agronomic characteristics and biological activities through exposure to light-emitting diode (LED) light. Seed germination was increased by 17.3 ± 4.7% in LED light-treated seeds of P. multiflorum compared with fluorescent light- treated (control) seeds (13 ± 4.2%). The biomass of the aerial parts of P. multiflorum increased to the greatest degree, with a stem length of 65.6 ± 4.2 cm and a leaf length of 5.4 ± 1.3 cm following red LED light treatment compared with control plants (stem length, 14.7 ± 4.5 cm; leaf length, 4.6 ± 1.2 cm). The epidermal cell size was 76.5-87.9 µm following exposure to red LED light by scanning electron microscopy based on biomass data. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical activity, total phenolic content, and total flavonoid content, including antioxidant activity, were also evaluated. In terms of DPPH activity, the samples extracted from roots had the highest reducible concentration 50% (RC50; 151.38 ± 0.31 μg ml -1 ) following blue LED light treatment. The total phenolic content was highest (535.07 μg GAE ml -1 ) in roots following blue LED light treatment. The total flavonoid content was highest (251.23 μg QE ml -1 ) in leaves following blue LED light treatment. Physiological analyses indicated increases in the biomass and biological activity of P. multiflorum treated with LED light. Our results suggest that treating P. multiflorum with LED light for 5 weeks can enhance food manufacturing and pharmaceutical production from natural substances.

The initial configuration for 95-seat passenger regional turboprop aircraft, the so called KC950, was designed to meet the market requirements. This paper prescribes the initial design based upon aircraft design guidelines and compared the competitive aircraft configurations after considering the related FAR 25 regulations. More specifically, results of design describe how to select the fuselage cross-sectional area, how to layout the cabin, and how to determine the overall shape and physical dimension of the fuselage. Sizing of wing and empennage areas is estimated using empirical equations and tail volume coefficients in this design. Some design guidelines to determine wing sweep angle, taper ratio, incidence angle and location are also introduced.

We investigated the functional mechanisms of brine mineral water (BMW) in plants. Antioxidant activities were determined by DPPH free radical-scavenging analysis of crude extracts of Rehmannia glutinosa treated with BMW. The DPPH was measured by value for the density of antioxidant required to absorbance equal to 50% that of a control containing no antioxidant. Plants treated with 0.05-0.1% BMW showed weak antioxidant activity. The concentrations of the principal mineral components, Mg 2+ , K + , and Sr 2+ were increased in samples treated with 1% BMW. Antimicrobial activities of BMW-treated R. glutinosa were determined. The greatest inhibition was against Salmonella typhimurium and Klebsiella pneumoniae. The effect of BMW treatment on plant growth over four weeks was investigated and determined by addition of distilled water into 100% BMW, which plant growth was enhanced about 8 cm by 0.05-0.1% BMW. The expression of marker genes involved in plant metabolism was monitored in control and BMWtreated plants. The RgAPX gene was induced in 5% BMW-treated plants after 48 h, and transcription of the PAL gene was significantly higher in 5% BMW–treated plants after both 1 and 48 h. In addition, rbcL gene expression was higher in BMW-treated than in control plants. These data suggest that BMW has various effects in plants. This work explains the relationship between biological activity and biomass in terms of the expression of functional genes. BMW affects biological activities, growth, and the secondary metabolism of plants.

Vehicle vibrations arise from engine and road surface excitations. The engine mount system of a passenger car sustains the engine weight and insulates the excitation force from the engine system. The dynamic properties of viscoelastic material used for the vehicle engine mounts have large variation due to environmental factors such as environmental temperature and humidity etc. The present study aims to investigate the variability of dynamic characteristics in rubber engine mounts considering both environmental temperature change and material model errors/uncertainty. The engine mounts for a passenger car were modeled using finite element method. Then, the dynamic stiffness variability of the engine mounts were estimated using Monte Carlo simulation method. In order to estimate the variations in the storage and loss moduli of the viscoelastic materials, the material properties of the synthetic rubber were expressed as a fractional-derivative model. Next, in order to simulate the uncertainty propagation of the dynamic stiffness for the engine mounts due to the storage and loss moduli variations, the Monte Carlo simulation was used. The Monte Carlo simulation results showed large variation of the engine-mount stiffness along frequency axis.

We investigated the expression of genes related to antioxidant mechanisms through transient overexpression of the glucose-6-phosphate isomerase (GPI) gene of Miscanthus sinensis in Nicotiana benthamiana leaves. Full-length cDNA was isolated from M. sinensis GPI (MsGPI). An analysis of the MsGPI amino acid sequence revealed significant similarities to the GPIs of Festuca ovima (94%), Hordium vulgare (94%), Triticum aestivum (94%), and Zea mays (97%). RT-PCR showed that MsGPI expression was induced significantly by NaCl. Transient M. sinensis GPI sense construct overexpression resulted in increased N. benthamiana ascorbate peroxidase (NbAPX) and phenylalanine ammonia lyase (NbPAL) transcript levels in N. benthamiana leaves. These observations suggest that MsGPI is involved in antioxidant metabolism and that it is a transcriptional regulator of NbAPX and NbPAL.

This study was carried out to compare the characteristics of seed germination and the first stage of growth in Cynanchum wilfordii (Maxim.) by different light conditions such ass fluorescent light, dark and light emitting diode (LED). There was not much difference from the germination rate of C. wilfordii (Maxim.) in different light conditions for 10 days. The highest of germination rate occurred over 91.11 percentage by LED red condition at 26℃. Also mean germination veloc- ity and promptness index were represented the highest results of 2.3 ea/day and 52.67 under red light, respectively. But mean germination time under both LED red and blue light was represented low data that it takes over three days for germi- nating of seed. Even though handling both LED red and blue lights, the germination uniformity was not constant. These results may help our understanding of variations in germination characteristics for C. wilfordii (Maxim.) seeds treated under different light conditions.

Advenced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185, KoreaAbstract - This study was carried out to evaluate the agronomic characteristics and biological activities of Sorghum bicolor germplasms introduced from USA. Plant height, stem diameter, tiller number, leaf length, leaf width, leaf vein color, ear type, ear length and ear width have different from the cultivated accessions. Sweet-N-Sterile (#4) showed the tallest height, widest ear-width and stem diameter. Most of Sorghum bicolor plants may be available to use for bio-energy from these results showing big biomass. Antioxidant activities of 11 cultivars collected from USA were examined by DPPH assay and reducing power. Among the cultivars, Premium stock (#1), Early Sumac (#7), SS Silage (#9) and WGF Grain Sorghum (#11) showed a significantly higher antioxidant activity in comparison to others. Early Sumac (#7) and SS silage (#9) showed more strong reducing power activities than α-tocopherol, a positive control. Premium stock (#1), Sweet-N-Sterile (#4), Early Sumac (#7) and SS Silage (#9) were also showed high antioxidant activities by DPPH assay and reducing power experiment. BMR Gold I (#3) displayed strong antimicrobial activity against Escherichia coli at minimum inhibitory concentrations (125 μg/ml).

This study was carried out to select the appropriate medium (especially, carbon and nitrogen source, potassium phosphate and pH) for somatic embryogenesis in order to develop the rapid mass production system in suspension culture of Oplopanax elatus Nakai. Direct somatic embryos were obtained from root explants in the hormone free suspension culture (MS). Combination of NH4NO3 and KNO₃ at the ratio of 1650 (㎎/ℓ ) : 1900 (㎎/ℓ ) obtained the better result to produce somatic embryo in suspension culture. MS medium supplemented with 170 ㎎/ℓ KH2PO4. The addition of 1 and 3% sucrose was effective for formation of embryogenic callus. Therefore, this report will be helped to improve the establishment for suspension culture in Oplopanax elatus Nakai.

This study is part of research to develop the technology for managing major medicinal crops after harvest. We studied the optimal germination conditions of Cynanchum wilfordii (Maxim.) Hemsl. The mean germination time (MGT) of C. wilfordii seeds was higher after soaking for 4 days after storage at 5℃ for 8 weeks, than with germination at 25 ℃ (3 days). However, the germinative energy (GE) decreased as the number of days soaking increased. The greatest germination rate (83.3 ± 8.8%) was at 25℃ with no soaking of seeds stored at-20℃ for 8 weeks. Based on these results, we characterized the germination conditions of a major medicinal crop.

This study was investigated seed germination of Rheum undulatum L. depends on storage temperature (-20, 5 ℃ and room temperature), germination temperature (5, 15, 25 and 40℃) and a soaking treatment (no soaking, 2 days and 4 days). There was not much difference from the germination rate of R. undulatum L. in storage temperature conditions for 8 weeks. The highest of germination rate occurred over 80 percentage at 25℃. When R. undulatum L. was soaked with tap water for four days, the average values of germination velocity and germination day were represented of 1.7 ea/day and 1.68 days. These results may help our understanding of variations in germination characteristics for R. undulatum L. seeds treated under various germination conditions.

*Department of Applied Plant Sciences, College of Agriculture and Life Science, Kangwon National University, Chuncheon 200-701, Korea.**Department of herbal medicine resource, Kangwon National University, Samcheok 245-907, Korea.***Ganagwon Agricultural Research & Extension Services, Crop & Agriculture Management Research Section, Chuncheon 200-150, Korea.****Department of Herbal Crop Research, NIHHS, RDA, Eumseong 369-873, Korea.ABSTRACT : This study evaluated the germination rate of Rheum palmatum L. in Korea as affected by storage temper-ature, germination temperature, and a soaking treatment. The germination rate of R. palmatum L. stored at various con-ditions for 8 weeks was > 60%. The highest germination rate occurred at 25