The Korean military has sought to build an all-round military force against the national and international security environment and future asymmetric threats as well as the military threats it faces. However, while raising the need for timely electrification, there are few cases of quantitatively evaluating the loss when electrification is delayed, making it difficult for our military to provide a logical basis to support the importance of the electrification period. Therefore, through this study, we tried to analyze the index of loss cost that can support the need for timely electrification with logical and quantitative data and present it as a logical basis. To this end, the loss cost was calculated in terms of combat efficiency, equipment utilization rate, and maintenance requirements, which can be quantitatively calculated based on “combat readiness,” a general impact on the military in case of delayed timely electrification.

Thermoelectric (TE) energy harvesting, which converts available thermal resources into electrical energy, is attracting significant attention, as it facilitates wireless and self-powered electronics. Recently, as demand for portable/wearable electronic devices and sensors increases, organic-inorganic TE films with polymeric matrix are being studied to realize flexible thermoelectric energy harvesters (f-TEHs). Here, we developed flexible organic-inorganic TE films with p-type Bi0.5Sb1.5Te3 powder and polymeric matrices such as poly(3,4-eethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and poly (vinylidene fluoride) (PVDF). The fabricated TE films with a PEDOT:PSS matrix and 1 wt% of multi-walled carbon nanotube (MWCNT) exhibited a power factor value of 3.96 μW ‧ m-1 ‧ K-2 which is about 2.8 times higher than that of PVDF-based TE film. We also fabricated f-TEHs using both types of TE films and investigated the TE output performance. The f-TEH made of PEDOT:PSS-based TE films harvested the maximum load voltage of 3.4 mV, with a load current of 17.4 μA, and output power of 15.7 nW at a temperature difference of 25 K, whereas the f-TEH with PVDF-based TE films generated values of 0.6 mV, 3.3 μA, and 0.54 nW. This study will broaden the fields of the research on methods to improve TE efficiency and the development of flexible organic-inorganic TE films and f-TEH.

This study was aimed to determine the effects of grow media on the mineral contents of the leaves and growth characteristics of strawberry grown under aquaponics system in a plant factory. For aquaculture, 12 fish (Cyprinus carpio) (total weight, 2.0 kg) were raised in an aquaponics tank (W 0.7 m × L 1.5 m × H 0.45 m, 472.5 L) filled with 367.5 L of water at a density of 5.44 kg·m-3 and total 34 of strawberry seedlings were transplanted in the pots filed with 200 g of orchid stone, hydroball or polyurethane sponge in the growing bed (W 0.7 m × L 1.5 m × H 0.22 m) laid out with holly acrylic sheet (140×60 mm, Ø80) on the top of the system. The pH and EC of the aquaponic solution was ranged from 7.6 to 4.9 and 0.24－0.91 dS·m-1, respectively. The concentration of NO3-N was about 28% lower than that of the hydroponic standard solution, and K, Fe and B were 10, 27 and 3.8 times lower, respectively; however, the mineral contents of strawberry leaves were in the appropriate ranges with lower contents in the leaves grown with sponge media. The organic content (OM), nitrogen (N), phosphorus (P), and potassium (K) of the sludge were 61.5, 5.72, 8.92, and 0.24%, respectively. The leaf area, leaf number, and dry and fresh weights of shoot at 81 DAT were significantly higher in the hydroball, and the average number of fruits per plant was significantly higher in both the orchid stone and hydroball. There was no significant difference in the fresh and dry weights of fruits. Integrated all the results suggest that the orchid stone and hydroball media are more effective to utilize nutrients in solid particles of aquaponic solution, compared to the polyurethane sponge.

In existing ceramic mold manufacturing processes, inorganic binder systems (Si-Na, two-component system) are applied to ensure the effective firing strength of the ceramic mold and core. These inorganic binder systems makes it possible to manufacture a ceramic mold and core with high dimensional stability and effective strength. However, as in general sand casting processes, when molten metal is injected at room temperature, there is a limit to the production of thin or complex castings due to reduced fluidity caused by the rapid cooling of the molten metal. In addition, because sodium silicate generated through the vitrification reaction of the inorganic binder is converted into a liquid phase at a temperature of 1,000 °C. or higher, it is somewhat difficult to manufacture parts through high-temperature casting. Therefore, in this study, a high-strength ceramic mold and core test piece with effective strength at high temperature was produced by applying a Si-Na-Ti three-component inorganic binder. The starting particles were coated with binary and ternary inorganic binders and mixed with an organic binder to prepare a molded body, and then heat-treated at 1,000/1,350/1,500 °C to prepare a fired body. In the sample where the two-component inorganic binder was applied, the glass was liquefied at a temperature of 1,000 °C or higher, and the strength decreased. However, the firing strength of the ceramic mold sample containing the three-component inorganic binder was improved, and it was confirmed that it was possible to manufacture a ceramic mold and core via high temperature casting.

본 연구는 유통 중인 곡류 87건 및 그 가공식품 66건을 대상으로 발암물질인 무기비소의 오염도를 조사하였다. 높 은 분리능과 감도를 가진 HPLC-ICP/MS를 이용하여 무기 비소 As(III), As(V) 및 유기비소 MMA, DMA, AsB, AsC 를 분석했으며, ICP/MS로 총비소를 정량하였다. 모든 곡 류에서 무기비소가 검출되었으며, 곡류의 총비소는 약 70- 85%의 무기비소와 약 10-20%의 DMA로 구성되었다. 곡 류 분석 결과, 담수재배 종인 쌀과 흑미에서 높았고, 밭 재배 잡곡은 오염도가 낮았다. 쌀의 평균 무기비소 농도 는 쌀눈 0.160 mg/kg, 현미 0.135 mg/kg, 백미 0.083 mg/ kg으로 외피에 비소가 많은 것으로 조사되었다. 곡류 가 공식품은 원재료의 종류와 함량에 따라 무기비소 농도가 달랐으며, 현미와 쌀눈 가공 제품에서 검출량이 많았다. 모든 시료는 기준규격을 초과하지 않았지만, 섭취 빈도가 높으므로 식품 안전을 위해 지속적인 모니터링이 필요할 것으로 판단된다.

North Korea continues to upgrade and display its long-range rocket launchers to emphasize its military strength. Recently Republic of Korea kicked off the development of anti-artillery interception system similar to Israel’s “Iron Dome”, designed to protect against North Korea’s arsenal of long-range rockets. The system may not work smoothly without the function assigning interceptors to incoming various-caliber artillery rockets. We view the assignment task as a dynamic weapon target assignment (DWTA) problem. DWTA is a multistage decision process in which decision in a stage affects decision processes and its results in the subsequent stages. We represent the DWTA problem as a Markov decision process (MDP). Distance from Seoul to North Korea’s multiple rocket launchers positioned near the border, limits the processing time of the model solver within only a few second. It is impossible to compute the exact optimal solution within the allowed time interval due to the curse of dimensionality inherently in MDP model of practical DWTA problem. We apply two reinforcement-based algorithms to get the approximate solution of the MDP model within the time limit. To check the quality of the approximate solution, we adopt Shoot-Shoot-Look(SSL) policy as a baseline. Simulation results showed that both algorithms provide better solution than the solution from the baseline strategy.

본 논문은 또 하나의 새로운 게임 체인저로 부상하고 있는 레이저 무 기의 개념·강약점·요구능력, 주요국 레이저 무기개발의 현황과 주요이슈, 그리고 한국의 레이저 무기개발의 현황·의의·과제를 분석하기 위한 것이 다. 제4차 산업혁명기술들이 각종 무기체계에 반영되어 전쟁을 전혀 새 로운 모습으로 변화시키고 있다. 레이저 무기와 같은 에너지 무기는 획 기적인 장점이 있어 ‘육군비전 2050’의 8대 게임 체인저 중의 하나다. 국방·군사 신기술인 레이저 무기는 물론 강약점이 있고 미사일 요격·방어 무기가 되기 위해서는 더 많은 개발이 요구되지만 극초음속무기 방어체 계 및 요격수단으로서의 가능성과 관련해서도 주목을 받고 있는 무기이 기도 하다. 새로운 창과 방패의 전략·전력이 함께 요구되고 있다. 향후 한국은 ①레이저 무기의 핵심전력으로의 유지·강화, ②기술격차의 극복과 민관군산학연의 협력, ③미래전 대비 자조적·공조적 노력의 강화에 힘써 나가야 할 것이다.

This research was conducted for dewatered sludge cake of industrial wastewater treatment, i.e., as the object of inorganic sludge discharged especially in iron & steel manufacturing shop which used Air drying system to reduce water content. That drying system's single-type cyclone separator was confirmed to have significantly lower separation efficiency on the conditions 20μm and below of particular size through computational fluid dynamics(CFD) analysis. However, we found out the primarily advanced value of separation efficiency on dual-type directly connected. Regarding separation efficiency on size of 10μm, the efficiency of a single-type was presented at 51.91%. On the other side, the efficiency of the dual-type was 97.88%. This advanced effect of the dual cyclone separator was checked at a demo facility of air drying equipment designed by 340m3/min of airflow on site.

Spinach (Spinacia oleracea L.), a green leafy vegetable, is well known as a functional food due to its biological activities. Vascular calcification is associated with several disease conditions including atherosclerosis, diabetes, and chronic kidney disease (CKD), and is known to raise the risk of cardiovascular diseases related morbidity and mortality. However, there are no previous studies that have investigated the effects of fermented spinach exract (FSE) against aortic and its underlying mechanisms. Therefore, this study investigated the effects and action of possible mechanisms of FSE on inorganic phosphate (PI)-induced vascular calcification in ex vivo mouse aortic rings. PI increased vascular calcification through calcium deposition in ex vivo aortic rings. FSE inhibited calcium accumulation and osteogenic key marker, runt-related transcription factor 2 (Runx2), and bone Morphogenetic Protein 2 (BMP-2) protein expression in ex vivo aortic rings. And, FSE inhibited PI-induced extracellular signal-regulated kinase (ERK) and p38 phosphorylation in ex vivo aortic rings. These results show that FSE can prevent vascular calcification which may be a crucial way for the prevention and treatment of vascular disease association with vascular calcification.

본 논문은 극초음속무기 개발의 군사안보적 함의와 한국의 게임체인저 로서의 가치와 과제를 분석하기 위한 것이다. 극초음속무기 개발이 안보 지형을 바꾸는 게임체인저의 새로운 이슈로 부상하고 있다. 러·중·미가 경쟁적으로 개발하고 있고 북한도 시험발사에 성공한 터이다. 극초음속 무기란 마하 5 이상의 속도를 발휘하는 모든 무기를 통칭되며, ①극초음 속 활공비행체와 ②극초음속순항미사일로 구분된다. 극초음속무기는 ① 고속 고기동성, ②시간 압박성과 모호성의 특성을 지니고 있다. 한국의 극초음속무기개발을 위한 향후과제는 ①경쟁력 있는 기술향상을 위한 제 반노력, ②민·관·군·산·학·연 공동연구와 장기적 국가지원, ③핵･WMD 대 응체계 보완방안으로서의 추진 등으로 요약해 볼 수 있다. 게임체인저로 서 가치를 지닌 극초음속무기 개발을 위한 경쟁력 있는 기술향상을 위한 선제적 노력이 요구되는 중요한 시점인바 최선을 다해 개발·대비해 나가 야 할 것이다.

신기술 무기의 등장은 인류역사에서 산업혁명이라는 이름으로 시대의 변화를 주도해왔다. 제4차 산업혁명시대 국방·군사분야 신기술의 특성은 ①지능성(intelligence), ②상호연결성(interconnectedness), ③편재성 (distributedness), ④디지털화(digitalization) 등이다. 신기술 무기 개발 동향은 ①자율형 무인체계, ②초음속 무기체제, ③양자역학기술 군사적 활용 등으로 요약해 볼 수 있다. 신기술 무기개발의 주요쟁점사항은 ① 신기술에 의한 위기안정성 훼손 가능성, ②AI에 의한 군사적 의사결정의 위험성, ③신기술에 의한 신뢰구축조치 증진 가능성 등이다. 향후 국제사 회는 신기술 등장으로 인한 불안정 극복을 위한 기존 군축구조의 한층 강화 및 신기술·신무기를 다룰 수 있는 새로운 군축체제의 설립을 요구 하게 될 것이다. 우리는 우리의 신기술 개발노력과 국제사회의 신기술에 의한 상호신뢰구축 증진모색과의 조화로운 병행에 대비해 나가야 할 것 이다.

본 연구의 목적은 북한의 전술핵무기 개발 경과와 한국에 미치는 함의를 규명하는 것이다. 북한은 2021년 1월 8차 당대회를 통해 핵능력 고도화와 전술핵무기 개발을 공표하였다. 그리고 지속적으로 핵능력과 투발수단을 발전시키고 있다. 핵능력에서 가장 기본적이고 중요한 것은 무기급 플루토늄(WGPu)과 고농축우라늄(HEU), 삼중수소 등 핵물질과 다양한 투발수단이다. 북한은 원자로 가동 후 재처리를 통해 획득할 수 있는 WGPu보다는 은밀한 지하시설에서 농축이 가능한 HEU 위주로 핵물질을 증산하고 있고, 삼중수소의 생산을 위해 영변 핵시설을 이용 할 수 밖에 없을 것으로 판단된다. 그리고 투발수단의 능력향상을 위해 KN-23, KN-24, KN-25와 이동식발사대(TEL), 열차이동발사 등 다양 한 투발수단의 실험을 지속하면서 전술핵무기능력을 고도화하고 있다. 북한의 핵개발 단계는 사실상의 핵보유국을 넘어서 실제 핵을 운용할 수 있는 핵전력 작전운용과 현대화 단계로 진입한 것으로 판단된다. 북한은 이를 통해 공세적 핵태세를 추구하고, 고강도 국지도발 감행 등 현상변경을 위한 강압으로 확증보복전략뿐만 아니라 한반도에서 적극적 전쟁수행전략을 구사할 것으로 예상된다. 이에 대한 새로운 대응전략이 요구되고 있다.