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Developmental Characteristics of Zophobas atratus (Coleoptera: Tenebrionidae) at Varing Temperatures (온도에 따른 아메리카왕거저리(Zophobas atratus)의 발육 특성)

  • Kwak, Kyu-Won;Kim, Sun Young;Lee, Kyeong Yong;Yoon, Hyung Joo
    • Korean journal of applied entomology
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    • v.61 no.2
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    • pp.357-368
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    • 2022
  • We investigated the developmental characteristics of super mealworm (Coleoptera: Tenebrionidae) at four different temperatures (25℃, 27℃, 30℃, and 33℃). The rearing conditions were 9L/15D, 65% RH, and 1,330 to 1,800 lux with wheat bran. The length of developmental period of 1 to 18 instars at each temperature showed that 30℃ was the shortest at 120.0±5.8 days, compared to that at 27℃ (132.6±10.7 days), 33℃ (136.5±9.2 days), and 25℃ (156.7±7.5 days). The larval developmental period was statistically significantly longer at 25℃, 27℃, and 30℃ compared to the length at 33℃. However, the death rate of larvae at 33℃ was 2.7-3.3 times higher than the rate at other temperatures. Body weight was heaviest at 30℃ followed by 27℃, 33℃, and 25℃. The patterns of head capsule, body capsule, and body length were similar to that of body weight. Regression analyses of developmental period, larval body weight, and length according to temperature revealed 29-30℃ as the most suitable temperature. The prepupa rate was 43.1% in 17 instars, 30.3% in 18 instars, 15.4% in 16 instars, 7.1% in 19 instars, 2.2% in 15 instars, and 1.9% in 20 instars, accounting for 88.8% in 16-18 instars. Prepupal period was longer at lower temperatures. For the average prepupal period of 15-18 instars, prepupa time was 18.8±1.9 days at 27℃, 18.8±2.3 days at 30℃, 23.0±2.4 days at 33℃, and 23.1±2.9 days at 25℃. The average pupal period of females and males was 11.1±2.2 and 11.6±2.4 days, respectively. The data indicate that the most suitable rearing temperature of super mealworm was 30℃.

A Consideration of Perception on Enforcement of Serious Accident Punishment Act(SAPA) among the Workers in the Nuclear Medicine Department (중대재해처벌법 시행에 따른 핵의학 종사자의 인식 고찰)

  • Lee, Joo-Young
    • Journal of the Korean Society of Radiology
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    • v.16 no.4
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    • pp.477-490
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    • 2022
  • Serious Accident Punishment Act(SAPA) went into effect as of Jan. 27, 2022. The subject of study was the worker of the nuclear medicine department and the investigation was aimed at identifying the present situation of their understanding on the issue in the here and now, which can be utilized as basic research for further study. The survey was conducted on 51 people of the worker in the nuclear medicine department. The general factors were classified by their gender, the scale of the hospitals, the period of career, and the detailed occupational categories. The conclusion was drawn, including 1 missing data in gender and 2 in the type of occupation. The targeted hospitals were tertiary hospital, university hospital, and general hospital which have nuclear medicine department in. The period of subjects' career was categorized by less than 3 years, 3 to 5 years, 5 to 10 years, and more than 10 years. The specific occupation was classified by in-vivo radiological technologist, radiation safety manager and others. The amount of pressure that the job entails was highest in the category of general hospital, the period of 3 to 5 years of job experience, and radiation safety manager each. The system of the code was well constructed in the category of general hospital, the period of less than 3-year career, and radiation safety manager, as they responded. The blood transmissible disease had the largest number of outbreak of accidents related to the serious industrial accident. In addition, the radiopharmaceutical dosing error had the highest number of outbreak of accidents related to the serious civil accident. Therefore, we need to improve SAPA, facility inspection, security of budget, security of professional manpower. It will help the stable use of radiation and ensure patient safety.

A Basis Study on the Optimal Design of the Integrated PM/NOx Reduction Device (일체형 PM/NOx 동시저감장치의 최적 설계에 대한 기초 연구)

  • Choe, Su-Jeong;Pham, Van Chien;Lee, Won-Ju;Kim, Jun-Soo;Kim, Jeong-Kuk;Park, Hoyong;Lim, In Gweon;Choi, Jae-Hyuk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.1092-1099
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    • 2022
  • Research on exhaust aftertreatment devices to reduce air pollutants and greenhouse gas emissions is being actively conducted. However, in the case of the particulate matters/nitrogen oxides (PM/NOx) simultaneous reduction device for ships, the problem of back pressure on the diesel engine and replacement of the filter carrier is occurring. In this study, for the optimal design of the integrated device that can simultaneously reduce PM/NOx, an appropriate standard was presented by studying the flow inside the device and change in back pressure through the inlet/outlet pressure. Ansys Fluent was used to apply porous media conditions to a diesel particulate filter (DPF) and selective catalytic reduction (SCR) by setting porosity to 30%, 40%, 50%, 60%, and 70%. In addition, the ef ect on back pressure was analyzed by applying the inlet velocity according to the engine load to 7.4 m/s, 10.3 m/s, 13.1 m/s, and 26.2 m/s as boundary conditions. As a result of a computational fluid dynamics analysis, the rate of change for back pressure by changing the inlet velocity was greater than when inlet temperature was changed, and the maximum rate of change was 27.4 mbar. This was evaluated as a suitable device for ships of 1800kW because the back pressure in all boundary conditions did not exceed the classification standard of 68mbar.

Effects of Climatic Factors on the Nationwide Distribution of Wild Aculeata (Insecta: Hymenoptera) (전국 야생 벌목 분포에 대한 기후요인 영향 연구)

  • Yu, Dong-Su;Kwon, Oh-Chang;Shin, Man-Seok;Kim, Jung-Kyu;Lee, Sang-Hun
    • Korean Journal of Environment and Ecology
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    • v.36 no.3
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    • pp.303-317
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    • 2022
  • Climate change caused by increased greenhouse gas emissions can alter the natural ecosystem, including the pollination ecosystem and agricultural ecology, which are ecological interactions between potted insects and plants. Many studies have reported that populations of wild bees, including bees and wasps (BW), which are the key pollinators, have gradually declined due to climate change, leading to adverse impacts on overall biodiversity, ultimately with agribusinesses and the life cycle of flowering plants. Therefore, we could infer that the rising temperature in Korean Peninsula (South Korea) due to global warming has led to climate change and influenced the wild bee's ecosystem. In this study, we surveyed the distributional pattern of BW (Superfamily: Apoidea, Vespoidea, and Chrysidoidea) at 51 sites from 2017 (37 sites) to 2018 (14 sites) to examine the effects of climatic factors on the nationwide distribution of BW in South Korea. Previous literature has confirmed that their distribution according to forest climate zones is significantly correlated with mean and accumulative temperatures. Based on the result, we predicted the effects of future climate changes on the BW distribution that appeared throughout South Korea and the species that appeared in specific climate zones using Shared Socioeconomic Pathways (SSPs). The distributions of wild BW predicted by the SSP scenarios 2-4.5 and 5-8.5 according to the BIOMOD species distribution model revealed that common and endemic species will shift northward from the current habitat distribution by 2050 and 2100, respectively. Our study implies that climate change and its detrimental effect on the ecosystem is ongoing as the BW distribution in South Korea can change, causing the change in the ecosystem in the Korean Peninsula. Therefore, immediate efforts to mitigate greenhouse gas emissions are warranted. We hope the findings of this study can inspire further research on the effects of climate change on pollination services and serve as the reference for making agricultural policy and BW conservation strategy

Floristic Characteristics of Vascular Plants in the Goyangsan Mtn.(Jeongseon-gun) and Munraesan Mtn.(Jeongseon-gun) Area (고양산(1,152.3m, 정선군)과 문래산(1,082.5m, 정선군) 일원의 관속식물)

  • Kim, Young-Chul;Chae, Hyun-Hee;Park, You-Cheol;Lee, Seon-Mi
    • Korean Journal of Environment and Ecology
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    • v.36 no.3
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    • pp.220-256
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    • 2022
  • The most important thing for conserving plant diversity in an area is to make an overall inventory of the plant species inhabiting the area. In particular, limestone areas are known for their high plant diversity and distribution of specific plants. Despite that, only a few have been designated as protected areas. This study investigated the vascular plants distributed in Goyangsan Mtn. and Munraesan Mtn., located in limestone areas of the central part of the Korean Peninsula. A field survey was conducted eight times from April to October 2021. As a result, we identified a total of 654 taxa comprising 113 families, 357 genera, 592 species, 15 subspecies, 44 varieties, and 3 formulas. They included four endangered wild plant species: Astilboides tabularis, Eleutherococcus senticosus, Cypripedium macranthos, and Epilobium hirsutum. Endemic plants in Korea were identified as 32 taxa. Floristic target plants were identified as 168 taxa, specifically 5 taxa of grade V, 41 taxa of grade IV, and 36 taxa of grade III. The red data plants included 2 taxa as "Endangered (EN)", 7 taxa as "Vulnerable (VU)", and 7 taxa as "Near threatened (NT)". A total of 41 taxa of naturalized plants were identified, and 4 of them were invasive alien plants. The surveyed vicinity of Goyangsan Mtn. and Munraesan Mtn. showed high plant diversity and contained core habitats for distribution of an endangered wild plant, Astilboides tabularis,in the limestone area. Moreover, both mountains contained a small population of Cotoneaster integerrimus. These findings confirm that the area has conservation values. Therefore, we propose to identify areas with high plant diversity and designate them as special protected areas.

The risk factors for implant survival and marginal bone loss: a retrospective long-term study (임플란트 장기간 유지와 변연골 소실에 영향을 주는 요인들에 대한 후향적 연구)

  • Lee, Eun-Woo;Jung, Ha-Na;Jo, Yujin;Kim, Ok-Su
    • Journal of Dental Rehabilitation and Applied Science
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    • v.38 no.2
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    • pp.97-109
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    • 2022
  • Purpose: This study aims to investigate the risk indicators contributing to implant failure, and analyze the relationship between risk indicators and marginal bone loss (MBL) through long-term follow-up over 3 years. Materials and Methods: From 2003 to 2017, patients' medical charts with a history of dental implant surgery at Chonnam National University Dental Hospital were reviewed retrospectively. The patient's demographic variables, and clinical variables were recorded. Periapical radiographs were used to evaluated the changes in MBL around implants. And we analyzed implant survival rates. Multiple regression analysis with backward elimination was conducted to correlate the patient's clinical variables and implant failure and Pearson correlation analysis was performed to the correlated between implant long-term survival rates and MBL and initial stability. Results: In multiple regression analysis, there was a statistically significant negative correlation between abutment connection type (β = -.189, P < .05), with or without SPT (β = -.163, P < .05), diabetes (β = -.164, P < .05), osteoporosis (β = -.211, P < .05) and MBL. Anticoagulant medication influenced the long-term success rate of implants. PTV values at the second implant surgery showed a statistically significant negative correlation with long-term implant survival (P < .05). Conclusion: For the long-term success of the implant, the appropriate abutment connection type must be selected and the periodic SPT is recommended. Systemic diseases such as diabetes and osteoporosis and anticoagulant medication should be considered. Furthermore, since high PTV at the second implant surgery correlated with the long-term survival rates of the implant, initial stability should be carefully considered before undergoing the prosthetic procedure.

Does Science Motivation Lead to Higher Achievement, or Vice Versa?: Their Cross-Lagged Effects and Effects on STEM Career Motivation (과학 학습 동기가 높은 학생이 과학 학업 성취도가 높아지는가, 또는 그 역인가? -양자가 지닌 교차지연 효과 및 이공계 진로 동기에 미치는 효과-)

  • Lee, Gyeong-Geon;Mun, Seonyeong;Han, Moonjung;Hong, Hun-Gi
    • Journal of The Korean Association For Science Education
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    • v.42 no.3
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    • pp.371-381
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    • 2022
  • This study causally investigates whether high school student with high science learning motivation becomes to achieve more or vice versa, and also how those two factors affect STEM career motivation. Research participants were 1st year students in a high school at Seoul. We surveyed their science learning motivation three times in the same time interval in the fall semester of 2021, and once a STEM career motivation in the third period. We collected data from 171 students with their mid-term and final exam scores, with which, we constructed and fitted an autoregressive cross-lagged model. The research model shows high measurement stability and fit indices. All the autoregressive and cross-lagged paths were statistically significant. However, standardized regression coefficients were larger in path from motivation to achievement compared to the opposite. Only science learning motivation shows significant direct effect on STEM career motivation, rather than achievement. For indirect effects, the first science learning motivation affected the final exam score and STEM career motivation, and the final exam score affected STEM career motivation. However, the final exam score did not have a total effect toward STEM career motivation. The result of this study shows reciprocal and cyclic causality between science learning motivation and achievement - in comparison, the effect of motivation for the opposite is larger than that of achievement. Also the result of this study strongly reaffirms the importance of science learning motivation. Instructional implications for strengthening science learning motivation throughout a semester was discussed, and a study for the longitudinal effect of science learning motivation and achievement in high school student toward future STEM vocational life was suggested.

A preliminary assessment of high-spatial-resolution satellite rainfall estimation from SAR Sentinel-1 over the central region of South Korea (한반도 중부지역에서의 SAR Sentinel-1 위성강우량 추정에 관한 예비평가)

  • Nguyen, Hoang Hai;Jung, Woosung;Lee, Dalgeun;Shin, Daeyun
    • Journal of Korea Water Resources Association
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    • v.55 no.6
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    • pp.393-404
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    • 2022
  • Reliable terrestrial rainfall observations from satellites at finer spatial resolution are essential for urban hydrological and microscale agricultural demands. Although various traditional "top-down" approach-based satellite rainfall products were widely used, they are limited in spatial resolution. This study aims to assess the potential of a novel "bottom-up" approach for rainfall estimation, the parameterized SM2RAIN model, applied to the C-band SAR Sentinel-1 satellite data (SM2RAIN-S1), to generate high-spatial-resolution terrestrial rainfall estimates (0.01° grid/6-day) over Central South Korea. Its performance was evaluated for both spatial and temporal variability using the respective rainfall data from a conventional reanalysis product and rain gauge network for a 1-year period over two different sub-regions in Central South Korea-the mixed forest-dominated, middle sub-region and cropland-dominated, west coast sub-region. Evaluation results indicated that the SM2RAIN-S1 product can capture general rainfall patterns in Central South Korea, and hold potential for high-spatial-resolution rainfall measurement over the local scale with different land covers, while less biased rainfall estimates against rain gauge observations were provided. Moreover, the SM2RAIN-S1 rainfall product was better in mixed forests considering the Pearson's correlation coefficient (R = 0.69), implying the suitability of 6-day SM2RAIN-S1 data in capturing the temporal dynamics of soil moisture and rainfall in mixed forests. However, in terms of RMSE and Bias, better performance was obtained with the SM2RAIN-S1 rainfall product over croplands rather than mixed forests, indicating that larger errors induced by high evapotranspiration losses (especially in mixed forests) need to be included in further improvement of the SM2RAIN.

A study on the effect of ground conditions of room and pillar method on pillar and room strain (격자형 지하공간의 지반조건이 암주와 룸 변형률에 미치는 영향에 대한 연구)

  • Ham, Hyeon Su;Kim, Yong Kyu;Park, Chi Myeon;Lee, Chul Ho;Kim, YoungSeok
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.23 no.6
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    • pp.577-587
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    • 2021
  • Room and Pillar method is an underground facility construction method that maximizes the strength of the in-situ ground. In order to secure the safety of the underground space, it is necessary to secure the safety of the room actually used in addition to the safety of pillar of the room and Pillar method. In this study, the evaluation method for the safety of the room and rock pillar in the room and pillar method was studied through numerical analysis. Numerical analysis was performed for a total of 125 cases using ground conditions, pillar width, and room width as parameters, and the results were derived. As for the safety factor of the pillar, it was confirmed that the safety factor increased when the strength of the ground increased, and it was confirmed that the increment in the safety factor decreased when the width of the pillar was widened. The room strain was evaluated by applying the Critical strain. As the width of the pillar became narrower, the Critical strain was higher, and as the width of the room became smaller, the Critical strain was smaller. As a result of the correlation analysis between the safety factor of the pillar and the room strain, it was possible to derive the upper limit of the room strain that can secure the standard safety factor of the pillar according to the width of the pillar. It is judged that the results derived from this study can be used as a guideline to secure the safety of the room when the actual design is performed in consideration of the ground conditions and room width.

A Study on the date of the black glazed bowls with "Gongyu (供御)" or "Jinzhan (進琖)" of Jian ware (건요(建窯) "공어(供御)"·"진잔(進琖)"명흑유완(銘黑釉碗)의 제작시기 문제)

  • Lee, Heegwan
    • MISULJARYO - National Museum of Korea Art Journal
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    • v.100
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    • pp.82-110
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    • 2021
  • This study specifically examined the date of the black glazed bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" of Jian ware, one of the key research topics related to the bowls. The results of this study can be summarized as follows. Jian Kiln produced various shapes of black glazed bowls, but almost all of the inscriptions of "Gongyu (供御)" or "Jinzhan (進琖)" are found only in two certain type bowls: Type I, the Shukou type bowls (束口碗), or Type II, the Piekou type bowls (撇口碗). Of these, there are significantly more of the former in existence. For Type I bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)", the mouth of the bowls is slightly evaginated outwards, and the inclination angle of the side slope is about 50°. The shape feature, Shukou (束口) is formed which is slightly indented around the bowl about 0.3~0.5cm below the mouth of bowl. And the height of the bowls is relatively low compared to other Type I black glazed bowls produced by Jian Kiln, so the height divided by the diameter is 0.5 or less. There is little difference in shape between the black glazed bowls marked with "Gongyu (供御) and those with "Jinzhan (進琖)". However, taking into consideration the excavation situation of both type bowls, the former is considered to be ahead of the latter in terms of production date. On the other hand, the black glazed bowls of Jian ware, which have the same shape features as the Type I bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" have not been found in the tombs dating from the end of the 12th to the beginning of the 13th century from which typical Jian kiln black glazed bowls of the same type were excavated. For the Hakata site (博多遺址) in Japan, the black glazed bowls with such a shape feature were excavated from early 12th century sites, rather than from the late 12th to early 13th century sites at which the typical black glazed bowls of Jian kiln were found. Considering that the black glazed bowls from Fujian province were imported into Hakata with almost no time gap, it is very unlikely that the production time of Type I black glazed bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" will deviate from the early 12th century. In conclusion, it is considered that the black glazed bowls marked with "Gongyu (供御)" or "Jinzhan (進琖)" of Jian ware were produced in the early 12th century.