콘크리트 도로포장의 보강재로 사용된 철근은 염해나 중성화 등으로 인하여 지속적인 손상이 발생하고 있으며, 이에 따른 유지관리 비용의 증대가 사회적 관심으로 대두되고 있다. 이를 해결하기 위하여 건설분야에서는 철근보다 내부식성 및 내알칼리성이 뛰어난 유 리섬유강화폴리머(Glass Fiber Reinforced Polymer, GFRP)가 사용되고 있다. 하지만, 수분 및 염해 등의 환경에 대한 내구성 검증은 충분히 이루어지지 않고 있는 실정이다. 따라서, 이 연구에서는 국내외에서 생산하는 직경 22mm GFRP 보강근을 ASTM D570에 의 거하여 흡수율 품질기준을 평가하였다. 흡수율 실험결과, 국내에서 생산된 GFRP의 경우 가장 높은 0.15% 수준의 흡수율을 나타내었으며, 해외에서 생산된 GFRP의 경우 0.03% 이내 수준의 흡수율을 나타내었다. 이는 KCI-GFRP 101 : 2024 및 ASTM D7957에서 제시하고 있는 GFRP 보강근 흡수율 품 질기준은 0.25% 이하를 모두 만족하는 것으로 분석되었다. 철근대체제로써 활용을 위해서는 장기침지 및 특수한 환경 등에 대한 내구 특성에 대한 추가적인 실험적 검토가 필요할 것으로 판단된다.

Code-compliant seismic design should be essentially applied to realize the so-called emulative performance of precast concrete (PC) lateral force-resisting systems, and this study developed simple procedures to design precast industrial buildings with intermediate precast bearing wall systems considering both the effect of seismic and blast loads. Seismic design provisions specified in ACI 318 and ASCE 7 can be directly adopted, for which the so-called 1.5S y condition is addressed in PC wall-to-wall and wall-to-base connections. Various coupling options were considered and addressed in the seismic design of wall-to-wall connections for the longitudinal and transverse design directions to secure optimized performance and better economic feasibility. On the other hand, two possible methods were adopted in blast analysis: 1) Equivalent static analysis (ESA) based on the simplified graphic method and 2) Incremental dynamic time-history analysis (IDTHA). The ESA is physically austere to use in practice for a typical industrial PC-bearing wall system. Still, it showed an overestimating trend in terms of the lateral deformation. The coupling action between precast wall segments appears to be inevitably required due to substantially large blast loads compared to seismic loads with increasing blast risk levels. Even with the coupled-precast shear walls, the design outcome obtained from the ESA method might not be entirely satisfactory to the drift criteria presented by the ASCE Blast Design Manual. This drawback can be overcome by addressing the IDTHA method, where all the design criteria were fully satisfied with precast shear walls’ non-coupling and group-coupling strength, where each individual or grouped shear fence was designed to possess 1.5S y for the seismic design.

This study presents code-compliant seismic details by addressing dry mechanical splices for precast concrete (PC) beam-column connections in the ACI 318-19 code. To this end, critical observations of previous test results on precast beam-column connection specimens with the proposed seismic detail are briefly reported in this study, along with a typical reinforced concrete (RC) monolithic connection. On this basis, nonlinear dynamic models were developed to verify seismic responses of the PC emulative moment-resisting frame systems. As the current design code allows only the emulative design approach, this study aims at identifying the seismic performances of PC moment frame systems depending on their emulative levels, for which two extreme cases were intentionally chosen as the non-emulative (unbonded self-centering with marginal energy dissipation) and fully-emulative connection details. Their corresponding hysteresis models were set by using commercial finite element analysis software. According to the current seismic design provisions, a typical five-story building was designed as a target PC building. Subsequently, nonlinear dynamic time history analyses were performed with seven ground motions to investigate the impact of emulation level or hysteresis models (i.e., energy dissipation performance) on system responses between the emulative and non-emulative PC moment frames. The analytical results showed that both the base shear and story drift ratio were substantially reduced in the emulative system compared to that of the non-emulative one, and it indicates the importance of the code-compliant (i.e., emulative) connection details on the seismic performance of the precast building.

This study improved the work efficiency by supplementing the shortcomings of the manual process by developing a double tube feeding device, and the following results were obtained by conducting the production capacity, production length, and defect rate tests. Developed a double tube production system to enable the simultaneous production of two tubes, increasing the production volume by about 1.5 times. The product length has been improved from semi-automatic to automated, and the production capacity has been improved from 16 to 25 pieces per hour (based on 15m). Developed a double-tube input straight line automatic adjustment feeder, which resulted in reducing the defect rate to less than 1%.

In this study, a core-shell powder and sintered specimens using a mechanically alloyed (MAed) Ti-Mo powder fabricated through high-energy ball-milling are prepared. Analysis of sintering, microstructure, and mechanical properties confirms the applicability of the powder as a sputtering target material. To optimize the MAed Ti-Mo powder milling process, phase and elemental analyses of the powders are performed according to milling time. The results reveal that 20 h of milling time is the most suitable for the manufacturing process. Subsequently, the MAed Ti-Mo powder and MoO3 powder are milled using a 3-D mixer and heat-treated for hydrogen reduction to manufacture the core-shell powder. The reduced core-shell powder is transformed to sintered specimens through molding and sintering at 1300 and 1400oC. The sintering properties are analyzed through X-ray diffraction and scanning electron microscopy for phase and porosity analyses. Moreover, the microstructure of the powder is investigated through optical microscopy and electron probe microstructure analysis. The Ti-Mo core-shell sintered specimen is found to possess high density, uniform microstructure, and excellent hardness properties. These results indicate that the Ti-Mo core-shell sintered specimen has excellent sintering properties and is suitable as a sputtering target material.

To produce super sweet corn sikhye, substituted for sweetener, the ratio of rice and super sweet corn was adjusted and processed with complex enzymes during saccharification, and their physicochemical and sensory properties were analyzed. The soluble solid content of the control and Corn-5 showed significantly high content at 13.50 °Brix, and the reducing sugar content of Corn-5 showed the highest content at 9.45%. The control showed the lowest free sugar content among all the experimental groups, excluding maltose content. In the enzyme-treated corn sikhye group, as the amount of super sweet corn increased, the content of sucrose decreased and the contents of glucose and fructose increased. The content of ascorbic acid and polyphenol compounds increased as the amount of super sweet corn increased. DPPH and ABTS radical scavenging abilities increased with increasing ratio of super sweet corn and enzyme treatment compared to the control. In the case of sensory evaluation, Corn-3, which substituted 30% of super sweet corn for rice and treated with enzymes, showed higher evaluations in taste, sweetness, and overall preference than those of the control.

As a result of this study, the performance evaluation of the development of laminated paper automatic adhesive processing machine is considered and concluded as follows. The cardboard processing unit for automatic folding and gluing designed a feeder for supplying cardboard, and the prototype production was compared with the existing production and the developed product, and the production rate was improved from 31,100 to 46,500 pieces per day, and the production speed was increased from 68 to 98. The defect rate was solved by solving the folding problem by comparing the existing production and the developed product, and the standard of the defect rate of the product was based on the folding, and the X1-X4 average defect rate was confirmed to be 0,000607%.

By developing a high-quality plexiglass sign using LED, it is possible to respond to international competitiveness and effectively cope with market expansion measures. The degree of inhalation of the fine dust blown by the air nozzle was tested so that it was not blown into the air. As a result of this test, the acrylic absorption rate was 82%, an increase of 20% from 60% before improvement, and the working environment was improved. With the development of the dust extraction device for the acrylic processing machine in this study, the suction and removal of acrylic fragments or dust is smoothly performed, resulting in a cleaner, more hygienic and improved safety through the improvement of the working environment. As a result of comparing the amount of burr generated in the plexiglass material and comparing the degree of test performance for reaching 24,000 rpm, it reached 24,000rpm.

To improve usability of super sweet corn, extracts were prepared with hydrolytic enzyme and changes in physicochemical and antioxidant properties were analyzed. Soluble solids and reducing sugars contents were higher in all enzyme treatment groups than in the control. When enzyme treatment time increased, contents of soluble solids and reducing sugars were also increased. There was no significant difference in lightness between treatment groups, with redness showing the highest value in the control and yellowness showing the highest value in the invertase treatment group. Free sugar content in the control was the lowest. However free sugar content in the enzyme combination treatment group was increased by more than four times compared to that in the control. Contents of ascorbic acid, flavonoids and polyphenols were higher in the enzyme treatment group than in the control. In particular, the enzyme combination treatment group showed the highest content. DPPH and ABTS radical scavenging abilities were significantly higher in all enzyme treatment groups than in the control. Radical scavenging abilities of cellulase treatment group and enzyme combination treatment group showed high activity. The activity increased when enzyme treatment time increased. The combined enzyme treatment method for super sweet corn was suitable for food processing.

2015년부터 2022년도까지 6개목(딱정벌레목, 노린재목, 나비목, 벌목, 파리목, 총채벌레목) 곤충들에 대해서 식물검역현장 검출실적과 국내 보고된 미기록종을 분석하였다. 해당기간 동안 국경검역에서 6개목 곤충은 총 45,084건이 검출되었다. 같은 기간 국내에서는 총 545종이 미기록종 으로 보고되었으며, 이중 9종은 국경검역에서도 검출된 것으로 확인되었다. 검역현장에서는 딱정벌레목, 총채벌레목, 노린재목이 높은 검출률을 보 였으며, 국내 미기록종 중에서는 벌목이 176종으로 가장 많이 보고되었다. 본 연구를 통해 침입압력(국경검역 검출)과 실제 침입(국내 미기록종 발 견) 사이에 비동시성이 확인되었다. 향후 보다 장기적인 분석이 필요할 뿐만 아니라 지속적인 식물검역시스템 개선이 필요할 것으로 판단된다.

벼밤나방[Sesamia inferens (Walker, 1856)](나비목: 밤나방과)은 벼 줄기를 가해하는 해충이다. 본 연구는 국내 몇 지역에서 벼밤나방의 연 중 세대수를 추정하였다. 북위 38° 부근의 세 지역에서 벼밤나방 성충이 성페로몬트랩에 포획되었다. 이는 국내 모든 지역에서 벼밤나방이 서식하 는 것을 나타냈다. 조사된 지역 대부분에서 단일사인곡선의 유효적산온일도 모델로 추정된 세대별 성충 발생 시기는 관찰된 성충 세대의 발생 시기 와 차이가 없었다. 이 모델을 사용하여 추정된 월동유충은 성충 마지막 세대로부터 유래할 가능성이 있다고 추정되었다. 중남부지역에서 가을동안 벼 포장에서 채집된 유충들을 25°C에서 사육하였을 때, 번데기의 약 70%가 용화전 유충 탈피를 보이지 않았다. 경남 고성에서 3월초에 채집된 유 충은 25°C 사육에서 유충 탈피 없이 용화하여 이 지역에서는 주로 마지막 유충 영기로 월동할 것으로 추정되었다. 모든 결과를 종합하여 벼밤나방 은 북위 38° 부근 지역에서는 주로 2세대, 북위 35.3° ~ 37.3° 사이 지역에서는 3세대가 경과할 것으로 결론지었다. 별도로, 시토크롬 c 산화효소 1 유전자의 염기서열을 분석한 결과, 성페로몬트랩에 포획된 종의 35%가 다른 종이었고, 이들은 형태적으로 벼밤나방과 혼동되지 않았다.

코로나 이후 시기가 도래하며 세계 각국은 빠른 경제 회복을 목표로 다양한 노력을 강구하고 있다. 이러한 측면에서 고성장기업에 관한 관심 역시 지속해서 높아지고 있는데, 지금까지 이루어진 다양한 고성장기업의 연구를 통해 국가 경제발전이나 고용 창출에 있어 고성장기업의 높은 기여도가 입증되었기 때문이다. 이처럼 기존 고성장기업 관련 연구의 경우 국가 경제 차원, 특히 고용 창출에 있어서 고성장기업의 역할을 강조하고 있다. 하지만, 혁신 관점에서 고성장기업의 역할을 언급하고 있는 연구는 많지 않다. 이에 본 연구에서는 기업 재무 데이터와 과학기술정책연구원의 2021년 한국기업혁신조사(KIS)(서비스업 분야)를 병합한 통합데이터를 구축하고 서비스업 고성장기업의 혁신 활동과 혁신성과에 대해 분석해보았다. 방법론 측면에서는 고성장기업이 갖는 특성으로 인해 발생할 수 있는 선택편의 문제를 해결 하기 위해 성향점수매칭방법론을 활용하였다. 분석 결과를 살펴보면 서비스업 고성장기업은 일반기업 대비 더 다양한 혁신 활동을 통해 더 많은 혁신성과물을 창출하고 있는 것으로 나 타났다. 특히, 상품혁신이나 비즈니스 혁신성과물 창출에 있어서 고성장기업이 긍정적인 역 할을 한다는 것은 기존 경제·사회적 관점에서 강조되어오던 고성장기업의 중요성을 혁신성 장 관점으로 확대하여 해석할 수 있는 결과이다. 다만, 연구·개발 유형이나 협력 R&D에서는 일반기업과 차별점을 찾을 수 없었는데, 이는 협력 연구·개발 강화를 통해 고성장기업이 보 유한 혁신역량이 일반기업자들에게 파급될 필요가 있음을 보여주는 결과이다. 이상의 분석 결과를 바탕으로 본 연구에서는 국가 혁신역량 강화를 위한 고성장기업 육성과 모니터링의 필요성, 고성장기업의 협력 활동 유인 통한 혁신의 파급효과 확대 등의 시사점을 제시하고자 한다.

본 연구는 우리나라에서 정부 R&D 지원이 기업의 R&D 투자에 미치는 영향에 대해 실증적으로 분석한다. 이를 위해 2012년부터 코로나 직전인 2019년까지 8년 간 『연구 개발활동조사』와 『국가연구개발사업 조사·분석』 그리고 기업 재무정보를 제공하는 『KIS-Value』를 연계하여 패널 자료를 구축하고, 정부 R&D 지원을 받은 기업의 R&D 투자에 미치는 영향을 성향점수매칭법(PSM)과 패널 이중차분법(DID)을 사용하여 추정한다. PSM-패널DID 분석 결과 정부 R&D 지원을 받은 기업은 그렇지 않은 기업과 비교하여 유의한 수준에서 R&D 투자를 확대하는 것으로 확인되었다. 세부 집단별로 살펴보면 정부 R&D 지원 횟수가 커질수록 기업의 R&D 투자 확대 효과는 더 커지며, 정부 R&D 지원금 규모가 일정 수준 이상인 경우에만 기업의 R&D 투자 확대 효과가 유의한 것으로 나타났다. 이러한 결과는 우리나라에서 기업에 대한 정부 R&D 지원은 민간 R&D 투자의 시장실패를 보완하는 본연의 역할을 하고 있으며, 실질적인 정책 효과를 내기 위해서는 중장기적인 관점에서 일정 규모 이상의 지원이 뒷받침되어야 한다는 것을 시사한다.

As the importance of the indoor environment increases. In response to that, performance test study was conducted for the development of high performance range hood. And the chamber casing mock-up was subjected to a performance test by applying a static pressure of 100[Pa] in accordance with KS C 9304: 2020, When the discharge port diameter was 100 mm, the standard flow rate() was 186.9 at 60.8W, the discharge port diameter was 125 mm, and the standard flow rate() at 52.0W was 184.6, which satisfies “B-type 160 to 200 (static pressure 100Pa)”. This is a result that meets the KS C 9304 : 2020.