Honey bees are crucial pollinators for agricultural and natural ecosystems, but are experiencing heavy mortality in Korea due to a complex suite of factors. Extreme winter losses of honey bee colonies are a major threat to beekeeping but the combinations of factors underlying colony loss remain debatable. Finding solutions involves knowing the factors associated with high loss rates. To investigate whether loss rates are related to Varroa control and climate condition, we surveyed beekeepers in korea after wintering (2021–2022 to 2022–2023). The results show an average colony loss rate of 46%(2022) and 17%(2023), but over 40% colony loss before wintering at 2022. Beekeepers attempt to manage their honey bee colonies in ways that optimize colony health. Disentangling the impact of management from other variables affecting colony health is complicated by the diversity of practices used and difficulties handling typically complex and incomplete observational datasets. We propose a method to 1) Varroa mite population Control by several methods , and 2) Many nursing bee put in hive before wintering.

이탈리안벌인 A, C, F계통과 코카시안벌인 D, V계통을 2005년부터 2007년까지 국내에서 수집하였다. 수집한 계통은 육종을 위해 격리 된 섬에서 근친교배를 통해 순계로 분리하였다. 이 연구는 꿀, 로열젤리 다수확계통 선발에 있어 개체군 선발과 육종 효율을 높이기 위해 수행되 었다. 23 개의 형태학적 특성을 평가하고 두 아종의 기존 데이터와 비교한 결과, 이탈리안벌 순계계통은 코카시안벌 순계 계통과 달리8개의 특성이 기존의 이탈리안벌과 유사해 더 많은 특성이 보존되고 있음을 알 수 있었다. 또한 국내에서 유지되고 있는 순계들은 타 지역의 동일 계통과 차 이를 보여 분리된 순계의 형태적인 특징이 확인되었다.

Aluminum (Al) - based powders have attracted attention as key materials for 3D printing because of their excellent specific mechanical strength, formability, and durability. Although many studies on the fabrication of 3Dprinted Al-based alloys have been reported, the influence of the size of raw powder materials on the bulk samples processed by selective laser melting (SLM) has not been fully investigated. In this study, AlSi10Mg powders of 65 μm in average particle size, prepared by a gas atomizing process, are additively manufactured by using an SLM process. AlSi10Mg powders of 45 μm average size are also fabricated into bulk samples in order to compare their properties. The processing parameters of laser power and scan speed are optimized to achieve densified AlSi10Mg alloys. The Vickers hardness value of the bulk sample prepared from 45 μm-sized powders is somewhat higher than that of the 65 μm-sized powder. Such differences in hardness are analyzed because the reduction in melt pool size stems from the rapid melting and solidification of small powders, compared to those of coarse powders, during the SLM process. These results show that the size of the powder should be considered in order to achieve optimization of the SLM process.

South Korea has over 0.38 million of managed honey bee (Apis cerana) colonies before 2009 years ago, which produce the highest quantity of honey in the Korea; however, almost colony (90%) were collapsed by Korean Sacbrood Virus (KSBV) in South Korea. Korean Sacbrood Virus (KSBV) is the pathogen of A. cerana Sacbrood disease, which poses a serious threat to honeybee A. cerana, and tends to cause bee colony and even the whole apiary collapse. Colony collapse of A. cerana was first reported on the Pyeong-Chang of the South Korea in 2009. Several scientists and governments has been tried research for cure the sacbrood disease in A. cerana colony by medicines and management techniques. Unfortunately, The sacbrood disease dosen’t improve. So, we were developed a better breed of A. cerana for resistance of sacbrood virus by selection and then artificial insemination. A. cerana breeding technique was first successful applied with A. cerana in Korean. Queens was grafted from sacbrood resistance line and then it was growing in sacbrood disease colony that was survived 100%. Altogether selected 18 queens were artificially inseminated and 2,000 drones of A. cerana in Korea was used to evaluate amount of semen collection. We are select two scabrood resistance A. cerana line (R and H). R line be used for rearing the Queen. Drone was reared in H line colony. The RH hybrid were not infected sacbrood virus even spread sacbrood virus (2×106). RH colonies have very excellent hygienic behavior, brood, and sacbrood disease resistance activity.

Supercapacitors are attracting much attention in sensor, military and space applications due to their excellent thermal stability and non-explosion. The ionic liquid is more thermally stable than other electrolytes and can be used as a high temperature electrolyte, but it is not easy to realize a high temperature energy device because the separator shrinks at high temperature. Here, we report a study on electrochemical supercapacitors using a composite electrolyte film that does not require a separator. The composite electrolyte is composed of thermoplastic polyurethane, ionic liquid and fumed silica nanoparticles, and it acts as a separator as well as an electrolyte. The silica nanoparticles at the optimum mass concentration of 4wt% increase the ionic conductivity of the composite electrolyte and shows a low interfacial resistance. The 5 wt% polyurethane in the composite electrolyte exhibits excellent electrochemical properties. At 175 ℃, the capacitance of the supercapacitor using our free standing composite electrolyte is 220 F/g, which is 25 times higher than that at room temperature. This study has many potential applications in the electrolyte of next generation energy storage devices.

Control mating is important aspect in bee breeding programs. The technique of artificial insemination is the possible one that can surely control mating of the selected drones with the virgin queen. This is the first time applied artificial insemination technique to control mating of A. cerana in Korea. Altogether 18 queens were artificially inseminated, and 2,000 drones of Korean A. cerana were used to evaluate amount of semen collection. Semen of A. cerana is much difficult to separate from mucus in comparing with A. mellifera. The average amount of semen can be collected from one A. cerana drone was 0.09 μl, whereas the A. mellifera was more than 6 times (0.58 μl semen per A mellifera drone). Obtaining 1 μl of semen have to collect from 11.94 drones that successful semen ejection and have to kill 17 A. cerana drones. Queens artificially inseminated with 4 μl of semen (once insemination) or 8 μl of semen (twice insemination, each with 4 μl of semen) started laying egg later than naturally mated queens 5.3 and 2.5 days, respectively. The onsets of oviposition of artificially inseminated queens were 12.5 to 15.3 days. Queens received twice inseminations started laying eggs 2.8 days earlier than those received only once insemination. Artificially inseminated queens produced exclusively brood and were similar as the naturally mated ones. The brood production of the queens received once insemination with 4 μl of semen was insignificantly different than those received twice inseminations or naturally mated ones, suggesting that one artificial insemination with 4 μl of semen is favorable.

The demand for energy storage devices capable of operating at high temperatures is increasing. In order to operate at high temperatures, a device must have excellent thermal stability and no risk of explosion. Ionic liquids are electrolytes that satisfy the above conditions, and studies on improving their performance have attracted great interest. Here, we report the results of a study on the fabrication of a supercapacitor that has a composite electrolyte prepared by dispersing fumed silica in an ionic liquid. The fumed silica filler exhibits improved ionic conductivity and lower interfacial resistance. In particular, the silica nanoparticles with diameters of 10 nm exhibit better electrochemical properties than fillers of other diameters and have excellent device performance of 33 times higher than the pristine ionic liquid at high temperatures. This study can be used to improve the electrolytes of electrochemical devices, such as the next generation battery or lithium ion battery.

전통회화에 사용된 각종 색 재료 즉 유기, 무기안료나 염료는 온도, 습도, 빛, 그리고 대기 오염에 의한 각종 화학 물질 등과 직접 반응하여 탈․변색을 유도하기도 하고, 안료와 결합된 각종 수지의 열화에 의해 손상되기도 한다. 본 연구에서는 조선종이라고 불리는 한지에 석록, 석청 무기 안료를 사용해 인위적인 노화시험을 시행하면서, 동시에 전시 관에 전시를 통해 환경 요인으로 인한 자연적 노화시험을 수행하였다. 인위적인 노화와 자연적인 환경시험에 의해 일어 난 화학적인 변화는 자외선-가시광선 분광기와 FT-IR, TGA, XRD을 통해 측정하였고, 전통회화의 변색은 색차계와 video microscope로 관찰하였다. 이를 통해 석록이 포함된 전통회화의 변색은 대기 중의 산도와 자외선에 의해 일어났음을 알 수 있었다.

건설현장에서 주로 사용하는 주요 가설기자재 규격에 대한 표준을 정하고 성능에 대한 신뢰를 확보하기 위하여 1992년 처음 도입된 가설기자재 성능검정제도는 2009년 안전인증제도로 변경되어 산업안전보건법 제34조(안전인증) 및 제35조(자율안전확인의 신고)에 근거하여 가설기자재 제조업체의 기술능력과 생산체계, 제품의 성능을 종합적으로 심사하고 안전인증기준에 적합 여부를 검증하여 안전인증표시(마크)를 사용할 수 있도록 하는 제도이다. 성능검정제도는 가설기자재 30종에 대해 제품의 성능만을 시험하여 합격증을 교부하였으나 2009년 1월 1일부터 의무안전인증 가설기자재 12종 33품목과 자율안전확인 신고 가설기자재 8종에 대해서 기술능력 및 생산체계와 제품의 성능을 심사하여 인증서를 교부하는 것으로 변경되었다. 가설기자재의 안전성 및 제품의 신뢰도 향상으로 건설공사 품질 및 안전이 확보됨에도 불구하고 일시적이며 부수적으로 사용되는 자재인 것으로 여겨져 가설기자재의 안전성 확보를 위한 관심과 노력은 매우 미흡하였다. 가설기자재에 대한 관심이 소홀한 가운데 안전성 여부를 확인하기 어려운 재사용가설재가 폭 넓게 사용되고 가설기자재의 가격경쟁이 심화됨에 따라 저가의 재료를 사용한 불법 가설기자재를 생산․유통하는 등 가설기자재 제도 전반에 불법적인 행위가 빈번히 이루어지고 있어 가설기자재 관련 제도와 제품에 대한 안전성과 신뢰의 문제가 다시 제기되고, 향후 가설기자재의 신소재(강화플라스틱 등) 및 신제품(접이식 틀비계 등) 등이 도입될 경우 현행 기준으로는 안전인증 또는 자율안전 확인을 받기 어려우므로 빠르게 진행되는 건설환경 변화에 적절하게 대응하지 못한다는 문제점 또한 제기되고 있다. 가설기자재 관련 문제점들과 제반 현황이 가설기자재를 제조하고 유통하고 사용하는 이해당사자간 신뢰를 잃고 있어 이해당사자간에도 제도 개선을 통한 가설기자재 시장의 정화와 개선이 필요하다는 공감대가 형성되고 있다. 따라서 정부는 가설기자재 관련 문제점을 종합적으로 검토하고 개선하기 위하여 다양한 방향으로 제도개선을 추진하고 있으며, 이와 같은 추진 대책의 일환으로 가설기자재 인증표시 기준에 관한 개선방안 마련을 위하여 가설기자재 생산․유통 및 사용 실태를 파악하고 가설기자재 관련 이해당사자 및 전문가의 의견 수렴 등을 통하여 가설기자재 인증표시 기준을 합리적으로 개선하고 효율적으로 관리하기 위한 연구가 필요하게 되었다. 본 연구를 통해 국내 건설산업에서 중요한 역할을 분담하고 있는 가설기자재의 안전성 향상과 신뢰성 회복을 위한 합리적인 개선방안을 도출하여 산업안전보건법령의 제‧개정에 반영할 필요가 있다.

In this study, the electroless nickel plating method has been investigated for the coating of Ni nanoparticles onto fine Al powder as promising energetic materials. The adsorption of nickel nanoparticles onto the surface of Al powders has been studied by varying various process parameters, namely, the amounts of reducing agent, complexing agent, and pH-controller. The size of nickel nanoparticles synthesized in the process has been optimized to approximately 200 nm and they have been adsorbed on the Al powder. TGA results clearly show that the temperature at which oxidation of Al mainly occurs is lowered as the amount of Ni nanoparticles on the Al surface increases. Furthermore, the Ni-plated Al powders prepared for all conditions show improved exothermic reaction due to the selfpropagating high-temperature synthesis (SHS) between Ni and Al. Therefore, Al powders fully coated by Ni nanoparticles show the highest exothermic reactivity: this demonstrates the efficiency of Ni coating in improving the energetic properties of Al powders.

The technique of artificial insemination is the possible one that can surely control mating of the selected drones with the virgin queen. This technique was first time applied with A. cerana in Korean. The average amount of semen can collected from one Korean A. cerana drone was 0.09 μl and 0.1 μl of Vietnamese one, whereas the A. mellifera was more than 6 times (0.58 μl semen per A mellifera drone). Obtaining 1 μL of semen have to collect from 11.94 drones that successful semen ejection. Queens artificially inseminated with 4 μl of semen (once insemination) or 8 μl of semen twice (each insemination with 4 μl of semen) started laying egg later than naturally mated queens 5.3 and 2.5 days, respectively. The onsets of oviposition of artificially inseminated queens were 12.5 to 15.3 days.

The Small hive beetle, Aethina tumida (Murray, A. 1867) (commonly abbreviated to SHB), is one of notifiable pest in the world. SHB were confirmed in the southeastern United States in 1998 in a apiary in Florida. The SHB also was found in Korea in 2016. The SHB larvae have relatively large heads and numerous protuberances covering their bodies. Upon full maturation, larvae have reached a length of 10 mm. Adult females are length and width of ± 5.5 mm and ± 3.4 mm. Naturally occurring small hive beetles can vary greatly in size, possibly depending on diet, climate, and other environmental factors. Additionally, we were analyzed the mitochondrial cytochrome oxidase I (COI) gene of the SHBs. The sequence of the COI gene of SHB was identical to that of SHBs in Korea, but different by fourteen positions from Italy.

Due to their environmental and economical consequences, invasive species have become a major concern worldwide. Among them, the yellow-legged hornet, Vespa velutina, is a keen hunter of domestic honeybees. They use olfactory cues from the prey to assess food information. In this study, we investigated the attraction behavior of V. velutina to honeybee pheromone under outdoor conditions. Nine honeybee pheromones were tested and compared in order to find the best attractant. When testing specific compounds, the honeybee queen pheromone, homovanillyl alcohol, proved highly attractive.

Graphene oxide (GO) powder processed by Hummer's method is mixed with p-type Bi2Te3 based thermoelectric materials by a high-energy ball milling process. The synthesized GO-dispersed p-type Bi2Te3 composite powder has a composition of Bi0.5Sb1.5Te3 (BSbT), and the powder is consolidated into composites with different contents of GO powder by using the spark plasma sintering (SPS) process. It is found that the addition of GO powder significantly decreases the thermal conductivity of the pure BSbT material through active phonon scattering at the newly formed interfaces. In addition, the electrical properties of the GO/BSbT composites are degraded by the addition of GO powder except in the case of the 0.1 wt% GO/BSbT composite. It is found that defects on the surface of GO powder hinder the electrical transport properties. As a result, the maximum thermoelectric performance (ZT value of 0.91) is achieved from the 0.1% GO/BSbT composite at 398 K. These results indicate that introducing GO powder into thermoelectric materials is a promising method to achieve enhanced thermoelectric performance due to the reduction in thermal conductivity.