The demand for high-strength steel is rising due to its economic efficiency. Low-cycle fatigue (LCF) tests have been conducted to investigate the nonlinear behaviors of high-strength steel. Accurate material models must be used to obtain reliable results on seismic performance evaluation using numerical analyses. This study uses the combined hardening model to simulate the LCF behavior of high-strength steel. However, it is challenging and complex to determine material model parameters for specific high-strength steel because a highly nonlinear equation is used in the model, and several parameters need to be resolved. This study used the particle swarm algorithm (PSO) to determine the model parameters based on the LCF test data of HSA 650 steel. It is shown that the model with parameter values selected from the PSO accurately simulates the measured LCF curves.

A bending experiment was conducted to verify the structural performance of the U-flange truss hybrid bean using rebars or steel pipes to reinforce the upper compression zone. As a result of evaluating the bending strength of the truss hybrid beam according to the Structural Design Standard (KDS 14 2020: 2022) by introducing the lattice member as a tensile resistance element, the following conclusions were obtained. Considering the lattice element as a tensile resistance element, the nominal bending strength was increased by 38.57 to 47.90 kN.m. As a result of reviewing the experiment as to whether the flexural member has proper ductility, it was found that it is desirable to place appropriate rebars, steel quality plans, and lateral restraints on the upper and lower parts of the hybrid beam to have sufficient ductility ratio.

본 연구는 ACI 등 규정에 없는 FRP 보강 콘크리트의 복보강에 대한 설계흐름도를 제시하였으며, 단보강과 복보강을 비교, 분석하였다. 다양한 파라미터 연구를 통해서 각각 단보강일 때의 이점과 복보강일 때의 이점을 분석하였다. 콘크리트의 단면이 작을수록 보강량이 클수록 복보강의 휨성능이 유리하며, 반대의 경우는 단보강이 유리한 것으로 나타났다. 콘크리트의 단면을 크게 하는 것이 FRP 보강량을 크게 하는 것보다 효과가 좋으며, 콘크리트 단면 중에서 콘크리트 높이를 크게 하는 것이 효과가 우수하게 나타났다. 콘크리트의 설계기준강도가 클수록, FRP의 탄성계수가 작을수록 단보강이 유리하며, 반대의 경우는 복보강이 유리한 것으로 나타났다.

A typical low and medium-sized neighborhood living facility in reinforced concrete building secures a high floor and pursues an efficient module plan(long span). Accordingly, research on the development of new hybrid beams that can innovatively reduce labor costs such as on-site installation and assembly while securing strength and rigidity is ongoing. In order to verify the structural performance of the U-flanged truss composite beam with newly developed shape, Experiments with various variables are required. Based on the results, this study is to evaluate the strength of U-flanged truss hybrid beam through the flexural strength of the Korea Design Code and experimental values. It was evaluated that nominal flexural strength was 110% to 135% higher than the experimental value.

For the practical application of U-flanged Truss Hybrid beams, the flexural capacity of hybrid beams with end reinforcement details using vertical steel plates was verified. The bending test of U-flanged Truss Hybrid beams was performed using the same top chord under the compressive force, but with the thickness of the bottom plate and the amount of tensile reinforcement. The initial stiffness and maximum load of the specimen with tensile reinforcement have a higher value than that of the specimen without tension reinforcement, but the more tensile reinforcement, the greater the load decrease after the maximum load. In the case of the specimen with tensile reinforcement, because the test result value is 76% to 88% when compared with the flexural strength according to Korea Design Code, the safety of the U-flanged Truss Hybrid beam with the same details of the specimens can’t ensure. Therefore, the development of new details is required to ensure that the bottom steel plate and the tensile reinforcement can undergo sufficient tensile deformation.

The U-flanged truss hybrid beam is a new composite beam made by pouring concrete into the U-flanged truss beam. In this study, an experimental study was performed to verify the shear capacity of U-flanged truss hybrid beams with the newly developed end reinforcement details. For all specimens, the maximum shear strength was determined by shear failure of concrete in the loading point The detail reinforced with stirrups at the end zone can exhibit the greatest shear strength, but the method of reinforcing the end zone using vertical steel plates, which is a relatively easy method to manufacture, is considered to be the most effective detail in terms of shear strength and ductility. Also, in the case of U-flanged truss hybrid beams reinforced with vertical steel plates at the end zone, the shear strength can be evaluated on the safety side by using the Korea Design Standard formula.

본 논고는 『史記』중「本紀」,「世家」,「列傳」의 대화문을 대상으로 하여 그라이스(Grice)의 대화협력원리 이론을 통해 화자의 화용양상을 살펴보았다. 협력원리로 화자의 대화를 분석해 보면 화자의 의도가 표면적 사전중심의 의미만이 아닌 이면의 함축적 정보에 의해 청자에게 효과적인 메시지가 전달되는 것을 알 수 있다. 함축은 화용론에서는 특히 중요한 개념이다. 기존의 통사론과 의미론이 문장 혹은 표면적 연구에 머물러 있었다면 화용의 관점에서는 발 화를 통해 화자가 상대방에게 전달하고자 하는 의도에 더 큰 비중을 둔다. 따라서 본 연구의 주된 목적은 기존의 연구와 번역에서 청자에 해당하는 독자에게 제공된 表謙副詞 “竊”과 “伏”의 부족한 함축적 정보를 알아보고 고전원문의 직역이 아닌 자연스러운 한국어 번역으로써의 대안을 살펴보는 것이다.

‘복하’품종은 농촌진흥청 국립식량과학원 고령지농업연구소에서 2016년도 육성한 사계성 딸기 신품종이다. ‘복하’는 ‘고하’ 품종을 모본으로 하고 ‘새봉3호’ 품종을 부본으로 2011년 교배하여, 고온장일조건에서 당도가 높고 꽃대가 연속적으로 출현되는 우수한 사계성 개체를 선발한 것이다. 대관령의 여름재배 작형에서 2014년 생산력 검정, 2015년 특성검정을 거쳐 ‘새봉 8호’로 계통명을 부여하고, 2016년에 지역적응성 시험을 거쳐 ‘복하’로 명명하였다. ‘복하’의 초형은 반개장형이며, 엽형은 타원형이며, 초세가 강하다. 과실모양은 원추형이며, 과색은 연한 붉은색이다. 엽수는 32.7매로 ‘고하’의 22.8매보다 9.9매 더 많다. ‘복하’의 당도는 9.2%로 ‘고하’의 9.0% 보다 0.2% 더 높다. ‘복하’의 평균과중은 9.5 g으로 사계성 품종 중에서 큰 크기에 속하는 편이고, 상품수량은 27,701kg·ha-1 으로 ‘고하’ 품종보다 72% 더 많았다. 신품종 사계성 딸기 ‘복하’는 수량 및 품질이 좋아 열대 및 아열대지역의 고원지대에서 재배가 가능한 사계성 딸기 품종이다.

U-flanged truss beam is composed of u-shaped upper steel flange, lower steel plate of 8mm or more thickness, and connecting lattice bars welded on the upper and lower sides. The hybrid beam with U-flanged steel truss is made in the construction site through pouring the concrete, and designated as U-flanged truss hybrid beam. In this study the structural experiments on the 4 hybrid beams with the proposed basic shapes were performed, and the flexural capacities from the tests were compared with those from the theoretical approach. The failure modes of each specimen were quite similar. The peak load was reached with the ductile behavior after yielding, and the failure occurred through the concrete crushing. The considerable increasement of deformation was observed up to the concrete crushing. The composite action of concrete and steel member was considered to be reliable from the behavior of specimens. The flexural strength of hybrid beam has been evaluated exactly using the calculation method applied in the boubly reinforced concrete beam. The placement of additional rebars in the bottom instead of upper side is proposed for the efficient design of U-flanged truss hybrid beam.

This study was conducted to find out the environmental, service sire and genetic effects for reproductive trait in certain purebred of pigs on Landrace and Yorkshire, and to suggest selection indicator which is to improve genetic capability on reproductive traits. There are five traits used on this analysis which are total number of born (NBT), number of born alive (NBA), piglets weight within litter (LW), average of birth weight on piglets within litter (ABW) and variation of birth weight on piglets within litter (VBW). With these data, the mixed model was established using 10,342 records collected from 2,527 sows of Landrace and 13,817 records collected from sows of 3,056 Yorkshire breeds and the variation of random effects and the genetic parameter were estimated by the REML method including service sire effects, permanent environmental effects and sow genetic effects. Due to characteristics of closed nucleus herd for using data on this study, given that it has been isolated breeding for about 19 years that progressed over 16 generations, genetic analysis was performed on all of these data and partial data of the current genetic group in which animals were born after 2011. The effects of service sire were estimated to be less than about 8% of total variation in all traits considered in the analysis. Permanent environmental effects were estimated about 2~14% of total variation in all traits considered. The heritability, which is the ratio of genetic variance among the total variance, was estimated to be 20~35% for LW and ABW in Landrace and Yorkshire, while it was about 10~14% for NBT. The genetic correlations between NBT and LW were 62~74% and between NBT and ABW were –28~-7%. Therefore, indirect selection for improving litter size could be possible with considering LW. Whereas, the genetic effect of the service sire effects for litter traits would be trivial.

Concrete has been widely used for material of bridge girder. However, Concrete is considered as inefficient material for long-span girder. Because it has low material strength compared with those of steel girder, huge cross sectional area are required to have same strength of steel girder bridges. UHPC(Ultra High Performance Concrete) as new material is developed to supplement this weakness of concrete. UHPC has high compressive strength and show softness behavior due to it is reinforced by fiber. If UHPC has no any reinforcement for shear, diagonal tension crack failure is dominant like normal concrete. So, reinforcement for shear is essential and prestress is efficient method of reinforcement for UHPC due to high compressive strength. However, design equation for shear strength suggested by K-UHPC Certification(2012) do not consider prestress effect. Therefore, this study investigate effect of prestress for shear strength of ultra high performance concrete I-girder by using finite element analysis program

Cymbidium kanran Makino is being threatened in its own habitats due illegal collecting and habitat changes by vegetation growth along historical landuse change. In this study, we established habitat restoration model for conservation of C. kanran based on ecological diagnosis. Through exploration to Jeju Island in 2014 and 2015, we identified 27 unknown habitats of C. kanran and in there, abiotic variables and vegetation structure and composition were quantified. Altitudinal distribution of C. kanran was between 200 m ~700 m a.s.l. and compared to distribution in 2004, Area of Occupation (AOO) decreased at 82%. Specific habitat affinity was not observed by evenly found in mountain slope and valley and summergreen and evergreen broadleaved forests, but likely more abundant in valley habitats with higher soil and ambient moisture. Total of 96 individual of C. kanran was observed with an average density of 942.6 individuals ha-1. The plants showed relatively short leaf length (average=10.7 cm±1.1 cm) and small number of pseudo bulbs (1.2±0.2). Flowering and fruiting individuals were not observed in field. C. kanran was classified into endangered plant species as CR (Critically Endangered) category by IUCN criteria. Phenotypic plasticity of C. kanran was likely support to sustain in more shaded habitat environment and recent habatat changes to closed canopy and low light availability may exhibit negatively effects to C. kanran’s life history. Restoring C. kanran habitat should create open environment as grassland and low woody species density.

In this paper, we present the result of analytical investigation pertaining to the structural behavior of steel-concrete composite plate girder with arch-type web stiffener. In the arch-type web stiffener located in the compression side of web, infill concrete is cast to strengthen the arch-type stiffener and also to exert resisting force against compression force. This type of composite steel-concrete plate girder bridge is built and is in service. To understand the behavior thoroughly, analytical parametric study was conducted by using the finite element method. As a result it was found that the effect of arch-type stiffener with infill concrete is considerable for the design of such type composite girder bridge.

It is same such as the provision of shear buckling strength of steel composite box girder web panel and plate girder web panel in Korea Highway Bridge Design Standards(2012). But the web panel of steel composite box girder is different from the web of plate girder in that the upper slab and lower flange are connected to the web. So a different shear behavior of the girders is expected. In this study, To calculate a reasonable elastic shear buckling strength of steel composite box girder web panel, ABAQUS program was used. The results from F.E.A and previous studies are compared.

It is same such as the provision of shear buckling strength of steel composite box girder web panel and plate girder web panel in Korea Highway Bridge Design Standards(2012). But the web panel of steel composite box girder is different from the web of plate girder in that the upper slab and lower flange are connected to the web. So a different shear behavior of the girders is expected. In this study, To calculate a reasonable elastic shear buckling strength of steel composite box girder web panel, ABAQUS program was used. The results from F.E.A and previous studies are compared. It is shown that the web shear buckling strength of steel composite box girder of Korea Highway Bridge Design Standards(2012) is the most conservative.

본 연구에서는 지역사회 내 사회복지서비스 전달체계 간 서비스중복에 대한 실천가들의 인식을 통해 서비스중복에 대한 보다 심층적인 의미와 이해를 제공하기 위한 목적으로 탐색하였다. 본 연구는 현상학적 연구 방법을 이용한 질적 연구로서, 연구의 참여자는 경기도 오산시 사회복지 기관(시설)에서 근무하는 실천가 5명으로, 자료수집기간은 2013년 1월부터 2013년 4월까지 이루어졌으며, 자료수집방법은 일대일 심층인터뷰로 이루어졌다. 인터뷰 횟수는 2회~4회이며, 1회 인터뷰 시간은 1시간~1시간 40분이었다. 자료수집과 자료분석은 동시에 이루어졌으며, 자료분석은 Giorgi의 분석방법을 적용하였다. 본 연구의 결과로, 사회복지서비스 전달체계에 근무하는 실천가들은 서비스중복에 관한 인식에 본질적 요소를 구성하는 구성요소 3개와 하위구성요소 14개의 주제로 구조화 되었다.3개의 주제는 조직차원, 지역사회 차원, 국가 차원 3개의 구성요소와 14개의 하위구성요소로 도출되었다. 14개의 하위구성요소를 살펴보면 조직 차원에 4개의 하위구성요소로 ‘종사자 업무과다’, ‘기관장(대표)의 인식 부족’, ‘시설(기관)의 장기적 종합계획의 부재’, ‘대상자를 고유 정보로 인식’으로 도출되었고, 지역사회 차원의 5개의 하위구성요소는 ‘대상자 정보 공유 미비’, ‘네트워크를 위한 공식적 기구 부재’, ‘사회복지 유사서비스 제공기관 증가’, ‘행정기관의 무책임성’, ‘시설 간 네트워크 노력 미비’로 도출되었고, 국가 차원의 5개의 하위구성요소는 ‘관련 법 부족’, ‘평가제도의 문제점’, ‘복잡하고 다양한 복지욕구의 증가’, ‘복지기관(시설)의 투명성 강조’, ‘복지 자원의 한계’로 도출되었다. 본 연구의 결과는 사회복지서비스 전달체계 간 서비스중복에 대한 심층적인 의미와 이해를 하는데 도움을 주고, 향후 지역사회 내 사회복지서비스 전달체계 간의 서비스중복을 개선하는 정책의 나아가야 할 방향에 대한 기초자료가 될 수 있을 것이다.

This study investigates web shear buckling behavior of composite box girder according to the aspect ratio. The nonlinear finite element analyses on composite box girder model having shell elements and solid elements were performed. Also, the steel was modeled as an elasto-plastic material. Ultimate web shear buckling behavior of composite box girder was analyzed, and were compared the inelastic analysis results with shear buckling behavior of plate.