In this study, we evaluated the effects of acid leaching on the properties of Cr powder synthesized using self-propagating high-temperature synthesis (SHS). Cr powder was synthesized from a mixture of Cr2O3 and magnesium (Mg) powders using the SHS Process, and the byproducts after the reaction were removed using acid leaching. The properties of the recovered Cr powder were analyzed via X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), particle size analysis (PSA), and oxygen content analysis. The results show that perfect selective leaching of Cr is challenging because of various factors such as incomplete reaction, reaction kinetics, the presence of impurities, and incompatibility between the acid and metal mixture. Therefore, this study provides essential information on the properties under acidic conditions during the production of high-quality Cr powder using a self-propagating high-temperature synthesis method.

본 연구는 국내 유통 농산물 535건을 대상으로 잔류농 약 실태조사를 수행하였다. 서울 등 13개 지역에서 수거 한 농산물 시료를 QuEChERS법으로 추출한 후 d-SPE로 정제하여 LC-MS/MS 및 GC-MS/MS로 분석하였다. 농산 물 15품목 535건 중 14품목 288건에서 잔류농약이 검출 (53.8%)되었으며, 검출된 농산물은 사과 40건, 고추 40건, 감귤 33건, 복숭아 31건, 기타 품목 144건이었다. 이 중 잔류허용기준을 초과한 농산물은 배추 1건으로, diniconazole 이 0.18 mg/kg으로 기준치의 약 2배 검출되었다. 총 검출된 농약은 91종으로 살균제 42종, 살충제 48종, 살선충제 1종 이었으며, dinotefuran 91건, carbendazim 75건, tebuconazole 61건, pyraclostrobin 59건이 가장 빈번하게 검출되었다. 따 라서 상기의 결과를 통해 과일류 및 채소류에 대한 지속 적인 잔류실태조사가 필요할 것으로 사료된다.

본 연구는 조직이 원격근무를 도입하고자 할 때 실질적으로 고려해야 할 사항들을 분석해 제안하려는 목적으로 실행되었다. COVID-19로 인해 확산된 원격근무는 생산성의 보전 및 일-가정 양립 등의 효용을 가져와 포스트 팬데믹 시대에서도 뉴노멀로 활용될 수 있다는 가능성이 타진되었다. 그러나 원격근무는 전염병으로 인한 위기 상황에서 주입적으로 실행되었을 뿐 그에 맞는 운영 방침이 정해지지 않아 기업들 의 효율적인 도입이 어려웠다. 기존부터 원격근무에 관련된 연구는 진행되고 있었다. 그러나 선행연구들 은 원격근무의 이론적인 방향성을 언급하거나 긍정적인 효과에 대한 기대점을 시사하는 내용이 주를 이루었고 원격근무를 도입하거나 개선하고자 하는 기업을 위해 정량적 기법을 활용하거나 구체적인 제도 수립을 위한 요인 제시에 있어서는 미흡한 상황이다. 이에 본 연구는 원격근무 도입 시 고려해야 할 핵심 요인을 도출하여 기업들의 원격근무 도입에 실용적이고 통합적인 관점을 제안하고자 하였다. 이를 위해 경영학계 교수 및 인사관리 전문가들로 구성된 패널을 대상으로 델파이 조사를 실시하였다. 델파이 연구 는 정립되지 않은 분야에서 방향성을 도출하기에 적합한 사회 연구 방법론이라고 할 수 있다. 따라서 델 파이에 관련된 선행연구를 따라 가장 적합한 방식으로 총 3차에 걸친 델파이 조사를 진행하였으며, 조사 결과 최종적으로 조직문화, 업무환경, 인적자원, 성과관리의 네 가지 영역에 걸친 16가지의 핵심 요인이 도출되었다. 본 연구는 원격근무와 관련된 명확한 가이드라인이 없는 상황에서 원격근무 도입 시 인사 관리자들이 실질적으로 고려할 수 있는 요인들을 체계화했다는 점에서 의의를 지닌다.

본 연구는 국내 차나무 품종을 대상으로 연평균 기온이 낮은 봉화군에 식재하여, 봉화지역 차나무 재배 가능성을 검토하고자 연구를 수행하였다. 봉화군 시험지 토양 조사 결과, 시험지별 토양의 pH, EC, 치환성양이온, 유효인산은 적정수준이었으며, 유기물 함량은 대체로 낮은 수치로 조사되었 다. 봉화군 시험지 기온 조사 결과, 최저 기온은 소천면이 -14.1℃로 가장 낮았고, 다음으로 춘양면 -12.6℃, 명호면 -12.6℃, -10.2℃ 순으로 모든 시험지는 -10℃ 이하의 낮은 온도로 조사되었다. 차나무 재배 생육평가 결과, 명호면 시험지에서 생육 정도가 가장 우수하였고, 다음으로 소천면, 온실, 춘양면 순으로 조사되었다. 또한, 재배품종 보향과 대조품종 다산은 시험지 생장량과 광합성량이 다른 수종에 비해 높은 것을 확인하였 다. 봉화지역과 하동지역에 식재된 참녹의 주요 생리활성물질인 catechin과 caffeine 함량을 조사한 결과, Catechin 함량은 EGC와 EC, EGCG 함량은 하동이 높게 조사되었고, 반면 ECG는 봉화지역의 참녹이 월등히 높았다. 총 catechin 함량은 봉화 5.23%, 하동 5.22%로 비슷하게 나타났다. Caffeine 함량은 봉화 0.05%, 하동 0.38%로 하동지역의 참녹이 높게 나타났다. 본 연구에서 봉화군 차나무 재배 생육평가 결과 명호면, 소천면이 차나무 재배에 유리할 것이며, 봉화지역 차나무 재배 시 재배품종 보향과 대조품종 다산은 재배 적응성이 높을 것으로 판단된다.

양돈산업은 돼지고기 내 웅취발생 예방을 위한 방법으 로 수컷 자돈에게 물리적 거세를 관행적으로 실시해왔다. 그러나 동물복지에 대한 관심이 고조됨에 따라 일부 국가 들에서는 고통 최소화 물리적 거세법 권장 또는 대체 방 법에 대해 연구를 수행하고 있다. 따라서 본 연구에서는 비거세돈(EM; entire male pigs) 및 거세돈(CM; castrated male pigs)에서 이눌린의 급여가 지방조직 내 웅취물질 농도에 미치는 영향을 구명하고자 실시하였다. 시험동물 은 총 26두의 3원 교잡돈(EM, n=18; CM, n=8)을 사용하 였다. 시험 처리구는 3% 이눌린의 급여와 비급여를 설정 하여 총 4개 처리구(EM0, EM3, CM0 및 CM3)로 구성하 였다. 웅취분석을 위해 지방조직은 등지방, 목지방 및 삼 겹지방을 수집하였다. 등지방 내 인돌 농도는 EM0에 비 해 CM3에서 감소하였고(p<0.05) 목지방 및 삼겹지방에서 는 처리구간 차이가 없었다. 지방조직 내 평균 인돌 농도 는 EM0에 비해 EM3, CM0 및 CM3에서 감소하였다 (p<0.05). 등지방 내 스카톨 농도는 CM0, CM3에서 EM0 보다 감소하였다(p<0.05). 또한, 목지방 내 스카톨 농도 및 지방조직 내 평균 스카톨 농도는 CM3에서 EM0과 EM3 보다 감소가 확인되었다(p<0.05). 그러나 안드로스테논 농 도는 분석된 지방조직들 모두에서 처리구간 통계적인 차 이가 없다. 이러한 결과들은 이눌린 급여에 의해 비거세 돈의 지방 내 웅취물질 저감에 부분적인 효과를 나타냈 을 뿐만 아니라 거세돈에서도 웅취물질 감소에 긍정적인 영향을 미쳤음을 시사한다. 따라서, 본 연구결과는 물리적 인 거세가 전면 금지된다면 동물복지형 사양관리 기술개 발의 기초자료로 활용할 수 있을 것이다.

This study analyzed the flow inside floating seedling equipment for Scapharca subcrenata. Due to the aging society of fishing villages, it is impossible to continuously input the labor force. Therefore, it is necessary to improve efficiency. Scapharca subcrenata has high per capita consumption. It serves as an important aquatic food resource. Scapharca subcrenata culture tends to be highly dependent on the natural environment. Production of Scapharca subcrenata is difficult to predict with low stability. In the past, manpower directly installed bamboo nets in mudflats. The seedling equipment devised in this study is a floating type and can be freely moved on the sea according to the prediction of Scapharca subcrenata generation. The flow around the floating seedling equipment was analyzed by numerical analysis. The physical phenomena of the flow around the net inside the floating seedling equipment were visualized. As a result, the space between the floating seedling equipment and the bottom net and the space between the net groups showed a lower flow rate than the inlet flow rate. It is expected that the low flow rate of the floating seedling equipment will have a positive effect on the attachment of Scapharca subcrenata.

This study presents a dry precast concrete (PC) beam-column connection, and its target seismic performance level is set to be emulative to the reinforced concrete (RC) intermediate moment resisting frame system specified in ACI 318 and ASCE 7. The key features include self-sustaining ability during construction with the dry mechanical splicing method, enabling emulative connection performances and better constructability. Test specimens with code-compliant seismic details were fabricated and tested under reversed cyclic loading, which included a PC beam-column connection specimen with dry connections and an RC control specimen. The test results showed that all the specimens failed in a similar failure mode due to plastic deformations in beam members, while the hysteretic response curve of the PC specimen showed comparable and emulative performances compared to the RC specimen. Seismic performance evaluation was quantitatively addressed, and on this basis, it confirmed that the presented system can fully satisfy all the required performance for the intermediate RC moment resisting frame.

산화적 스트레스는 세포 및 조직 손상을 통해 피부의 탄력 및 보습 기능 저하, 피부 노화 촉진 을 비롯한 다양한 피부질환을 일으킨다. 본 연구의 목적은 인간 피부각질세포 (HaCaT keratinocyte)에서 산화적 스트레스에 대한 붉은 토끼풀 추출물의 효능을 검토하여, 피부에 효과적으로 사용할 수 있는 기능 성 소재로서의 활용 여부를 확인하고자 하였다. 본 연구에서는 붉은 토끼풀 추출물이 인간 피부각질세포에 서 산화적 스트레스에 따른 세포사를 억제시키는 것을 확인하여, 이를 조절하는 보호기전을 규명하였다. 이는 붉은 토끼풀 추출물이 Caspase-3 비활성, 세포사 촉진단백질 Bax 발현 억제, 세포생존 촉진단백질 Bcl-2 발현 증가 및 MAPK 신호전달계 단백질의 인산화 억제를 통해 H2O2에 의해 유도된 산화적 스트레 스를 보호할 수 있다는 것을 확인하였다. 따라서 붉은 토끼풀 추출물은 피부의 산화적 손상을 감소시키는 유용한 소재로 평가되며, 이는 피부보호 및 미용을 위한 다양한 제품 및 산업에 활용 가능성이 높은 것으로 판단된다.

This study was conducted in an indoor cultivation room and chamber where environmental control is possible to investigate the effect of temperature and irrigation interval on photosynthesis, growth and growth analysis of potted seedling cucumber. The light intensity (70 W·m-2) and humidity (65%) were set to be the same. The experimental treatments were six combinations of three different temperatures, 15/10℃, 25/20℃, and 35/25°C, and two irrigation intervals, 100 mL per day (S) and 200 mL every 2 days (L). The treatments were named 15S, 15L, 25S, 25L, 35S, and 35L. Seedlings at 0.5 cm in height were planted in pots (volume:1 L) filled with sandy loam and treated for 21 days. Photosynthesis, transpiration rate and stomatal conductance at 14 days after treatment were highest in 25S. These were higher in S treatments with a shorter irrigation interval than L treatments. Total amount of irrigation water was supplied evenly at 2 L, but the soil moisture content was highest at 15S and lowest at 25S > 15L > 25L, 35S and 35L in that order. Humidity showed a similar trend at 15/10℃ (61.1%) and 25/20℃ (67.2%), but it was as high at 35/25°C (80.5%). Cucumber growth (plant height, leaf length, leaf width, chlorophyll content, leaf area, fresh weight and dry weight) on day 21 was the highest in 25S. Growth parameters were higher in S with shorter irrigation intervals. Yellow symptom of leaf was occurred in 89.9% at 35S and 35L, where the temperature was high. Relative growth rate (RGR) and specific leaf weight (SLA) were high at 25/20℃ (25S, 25L), RGR tended to be high in the S treatment, and SLA in the L treatment. Water use efficiency (WUE) was high in the order of 25S, 25L > 15S > 15L, 35S, and 35L. As a result of the above, the growth and WUE were high at the temperature of 25/20℃.

In this study, the safety aspects were studied by comparing the charge control characteristics of the two vehicles when a failure occurs between the OBC including the charging port or the charging door module (CDM) during slow charging using the In Cable Control Box (ICCB) for a long time.When the AC terminal was momentarily disconnected during charging, the Model-3 vehicle was charged normally if the AC circuit was disconnected up to three times, and the charging control was stopped when the number of disconnects reached four times. However, in the Ioniq-5 vehicle, charging control was normally performed when the disconnected AC circuit was normally connected regardless of the number of disconnection.

This study aims to select eggplant cultivars adaptive to the hot temperature period greenhouse climate by water consumption, and growth performance of plants and fruits of different European eggplant cultivars, including ‘Bartok (BA)’, ‘Bowie (BO)’, ‘Black Pearl (BP)’, ‘Ishbilia (I)’, ‘Mabel (M)’, ‘Vestale (VE)’ and ‘Velia (VL)’, in substrate hydroponic cultivation under hot and humid greenhouse conditions. On the 118 DAT, the leaf number and stem dry weight were highest in ‘VL’, followed by ‘M’, and there was no significant difference in leaf dry weight among cultivars. The marketable fruit number per plant was 16.4 for ‘M’, which was higher than other cultivars, and ‘VE’ and ‘VL’ were 8.5 and 8.8, respectively. The weight per fruit was low for ‘M’ at 136 g, and the highest in ‘VE’ and ‘VL’ at 332 and 281 g, respectively. There was no significant difference in fruit production per plant. In this study, ‘M’, which has high water use efficiency and a large number of fruits, and ‘VL’, which required less quantity to water consumption for producing 200 g of fruit and had a high product weight, will have excellent adaptability in the UAE greenhouse condition.

The labor environment in Korea has changed and problems related to employment types are treated as important issues. Especially, the ratio of irregular workers has not only increased relatively, but the labor conditions in Korea also have worsened in the current years. Studies have reported an association between temporary workers and the prevalence of diseases. However, there is insufficient research on chronic disease and employment types. Methods: The current study examines the prevalence rate of diseases and health behavior by categorizing employment types among Korean adults. Data were obtained from the 2016-2018 Korea National Health and Nutrition Examination Survey. Totally, the data of 2,366 workers (1,239 regular and 1,127 irregular) were analyzed in the study. The types of employment were classified by a questionnaire querying about working conditions. The results showed that irregular workers earned less than regular workers and had a significantly higher prevalence of diabetes mellitus and hypertension. We propose that if discrimination related to working conditions were relieved, irregular workers would be able to invest more time to exercise and doing check-ups regularly. In addition, individual nutrition consultations considering the knowledge and personal environmental factors of each individual are necessary for the improved health of all workers.

This study aimed to investigate the effect of a coating agent on pork storage. Pork was coated with a coating agent containing sodium carboxymethyl cellulose (CMC) and mandarin peel powder (M). The treatments were divided into control, a 0.1% CMC treatment, and a 0.1% CMC +5% M treatment, and pH, color, 2-thiobarbituric acid reactive substances (TBARS), volatile basic nitrogen (VBN), and the number of viable cell counts were measured. In the case of redness (a), it was found that the reduction over the storage period was less in the 0.1% CMC + 5% M treatment than in the control and the 1% CMC treatment. When stored at 4oC and 25oC, TBARS of pork tended to increase during the storage period, followed by control, 0.1% CMC treatment, and 0.1% CMC + 5% M treatment, indicating that lipid oxidation was most suppressed in pork coated with mandarin peel powder. As a result of measuring the VBN of pork stored at 4oC and 25oC, the 0.1% CMC + 5% M treatment showed lower values than the control and 0.1% CMC treatment. When the film-coated pork was stored at 4oC, the number of viable cell counts in the 0.1% CMC +5% M treatment area was 7.13±0.96 log CFU/g on the 12th day of storage, delaying the growth of viable cell counts for approximately 3 d more than other treatments. Therefore, coating pork with a film containing CMC and mandarin peel powder has been confirmed to delay the increase in the number of viable cell counts while reducing the quality change during pork storage, which is an effective alternative to improving the storage of fresh food as an edible film.