In the recent years, thin film solar cells (TFSCs) have emerged as a viable replacement for crystalline silicon solar cells and offer a variety of choices, particularly in terms of synthesis processes and substrates (rigid or flexible, metal or insulator). Among the thin-film absorber materials, SnS has great potential for the manufacturing of low-cost TFSCs due to its suitable optical and electrical properties, non-toxic nature, and earth abundancy. However, the efficiency of SnS-based solar cells is found to be in the range of 1 ~ 4 % and remains far below those of CdTe-, CIGS-, and CZTSSe-based TFSCs. Aside from the improvement in the physical properties of absorber layer, enormous efforts have been focused on the development of suitable buffer layer for SnS-based solar cells. Herein, we investigate the device performance of SnS-based TFSCs by introducing double buffer layers, in which CdS is applied as first buffer layer and ZnMgO films is employed as second buffer layer. The effect of the composition ratio (Mg/(Mg+Zn)) of RF sputtered ZnMgO films on the device performance is studied. The structural and optical properties of ZnMgO films with various Mg/(Mg+Zn) ratios are also analyzed systemically. The fabricated SnS-based TFSCs with device structure of SLG/Mo/SnS/CdS/ZnMgO/AZO/Al exhibit a highest cell efficiency of 1.84 % along with open-circuit voltage of 0.302 V, short-circuit current density of 13.55 mA cm−2, and fill factor of 0.45 with an optimum Mg/(Mg + Zn) ratio of 0.02.

This study was conducted to investigate the community structure and species distribution of ground beetle assemblages in Yeongwol-gun (19 sites) and Donggang river basin area (6 sites). Ground beetles were collected by pitfall traps from 19 study sites from 2013 to 2014. A total of 67 species were identified from 9,710 collected ground beetles. Species richness in mountainous forests of Yeongwol-gun (55.8±1.90) estimated by rarefaction curves was higher than those in Donggang river areas (28.0±0.06). Four dominant species, Synuchus nitidus (3,974 individuals) and Synuchus cycloderus (2,595 individuals), Synuchus sp.1 (830 individuals), and Eucarabus cartereti cartereti (434 individuals) were occupied 80.7% of total, but their relative abundance were different according to geographical locations. Species richness of total carabid beetles was positively related to elevation (linear regression, F1, 23 = 22.41, adj. r2=0.47, P < 0.001) and it showed a U-shaped curve with longitudinal gradient (curvilinear regression, F2, 22 = 10.82, adj. r2=0.50, P < 0.001). And species richness maps that are focused on south-western areas of Gangwon-do including Yeongwol-gun, Jeongseon-gun, and Pyeongchang-gun were generated using ArcGIS 10.1. In species composition, longitude and elevation were best predictors to determine the distribution of carabid beetles by MRT analysis (Error = 0.517, CV Error = 1.04). These results indicated that habitat management regimes for biodiversity conservation should be conducted in considering geography and topography, although further studies are still necessary on the distributional pattern of other insect taxa and the relationship between biodiversity and more environmental variables.

This study was conducted to investigate the community structure and species distribution of ground beetle assemblages in western part of Yeongwol-gun, Korea. Ground beetles were collected by pitfall traps from 9 study sites during July to October in 2013. A total of 30 species were identified from 4,439 collected ground beetles. Two dominant species, Synuchus nitidus (1,916 individuals) and Synuchus cycloderus (1,900 individuals) were occupied 85.8% of total. Interestingly, Pterostichus orientalis orientalis and Synuchus melantho were only collected in relative high altitude above 350 m, such as Beopheung-ri, Unhak-ri, and Yongseok-ri. Large-sized beetles, such as Damaster, Leptocarabus, and Carabus species, were generally more collected from Suju-myeon (Beopheung-ri and Unhak-ri) and Jucheon-myeon (Docheon-ri and Yongseok-ri) as well-conserved area, but not occurred in Yeongwol-eup and Hanbando-myeon, which forests may have lower habitat quality for these species. These differences also lead to increasing of dissimilarity among study sites, which were diverged into 3 groups at 53.0% of similarity. In particular, species composition of Samok-ri was significantly different at 8.2% of similarity because of difference in habitat characteristics as river side. This study has an important value to provide the fundamental information of inventory and monitoring in Yeongwol-gun. For detail mapping of species distribution in Yeongwol-gun, however, further studies are necessary, especially eastern parts of Yeongwol-gun.

Rice stem borer, Chilo suppressalis Walker is a significant rice insect pest. A newly hatched larva bores a hole into the rice stem and feeding inside. The damage results in drying and white heads of rice. Climate change will affect pest and its host population dynamics variously. In this study, the degree of asynchrony between emergence of rice stem borer and rice transplanting was examined by their phenology models. Also, correlation was examined between winter mortalities of the rice stem borer and relative humidity categorized by daily minimum temperature in 12 sites throughout the country from 1992 to 2013. The degree of asynchrony appears to be increased in future climate condition. And we found a negative correlation between winter mortality and the relative humidity. Winter mortality will be decreased in the future because of increasing winter minimum temperature and snowfall. We hypothesize that the stem borer may increasingly harbor in alternative hosts such as reed in its first generation and move to rice in the second generation. Currently the simulation study is being conducted to verify this hypothesis.