In this study, we investigated culturable bacterial abundance in various crops. Total culturable aerobic bacteria in tomato plants were enumerated on NA and it showed that the amounts of viable bacterial cells were changed among the different parts of the plants (roots, stems, and fruits), ranging between log 1 and 4 per g sample. To investigate the bacterial abundance dynamics in different crops, culturable aerobic bacterial cell numbers were enumerated on NA and compared between the samples (tomato fruit, sesame leaf, and green onion) harvested freshly from one field trial (Yangsan, Korea). In this trial, the number of total culturable aerobic bacteria of the samples were 8 times higher in sesame leaves and green onions compared to the tomato fruits in the field. Interestingly, culturable aerobic bacteria on MRS were only found in sesame leaves, whereas lactic acid bacteria were not detected in tomato fruit and green onion samples in this field. We also found that the field location (Yangsan, Gangneung, or Busan) influenced the number of culturable aerobic bacteria on the surface of the crops. Tomato samples freshly harvested from the different field locations were tested and showed that the amounts of culturable aerobic bacteria on NA and MRS agar were significantly different based on the field locations of the samples. Finally, lactic acid bacteria were isolated from all the tomato and sesame leaf samples used in this study, showing 20 and 28 morphological diversity. With these isolates, we will be able to conduct further biological and functional investigation to develop a new probiotic strain originated from the crops in Korea.

The aim of this study is to investigate the awareness and satisfaction level of school meal services by elementary school students and their parents. Approximately 97.2% of student-subjects have agreed on the necessity of a free meal service for school lunch; 44.3% of student-subjects voiced the need to provide free meal services in order to eliminate discrimination of low-income students. Over one-third of student-subjects (36.7%) cited nutrition as the main benefit of providing a free meal service. The majority of parent-subjects (95.1%) have recognized the need for a free meal service in school; approximately 37.3% of parent-subjects responded to need the free meal service in order to eliminate the discrimination of impoverished students. Both student- and parent-subjects expressed a high level of satisfaction with the quality of ingredients and the type of soup/nutrition provided. Student-subjects insisted on better food hygiene and a new menu, but cited the noisy cafeteria as a problem associated with school meal services. In addition, approximately 56.5% of student-subjects responded to the need for nutritional education in school. Parent-subjects were primarily concerned with hygiene regarding the preparation of school meal services, noting the temperature of foods as the biggest problem in school meal services. The majority of parent-subjects (88.1%) responded to the need for the nutritional education in school. Results of this survey indicate that school meal services can be improved by increasing menu options and increasing food hygiene.

This paper presents the design, analysis, and experimental evaluations of precast reinforced UHPC (ultra high-performance concrete) beams with a new design concept of non-uniform flexural members. With outstanding mechanical properties of UHPC which can develop the compressive strength up to 200MPa, the tensile strengths up to 8~20MPa and the tensile strain up to 1~5%, a non-uniform structural shape of UHPC flexural beams were optimally designed using three-dimensional finite element analysis. The experiments were carried out and compared with the design strength in order to verify the performance of them. Proposed non-uniform UHPC beams were evaluated by a series of three-point beam loading test as well as estimated by design bending and shear strength of members. The newly designed UHPC beams show excellent performances not only in transverse load capacities but also in deformation capacities.

In current research, it was attempted a preliminary design and evaluation of non-uniform ultra high-strength concrete (UHSC) truss members. UHSC used here has the compressive strength of 180 MPa, the tensile strength of 8 to 20 MPa, and the tensile strain after cracks up to 2%. By the three-dimensional finite element stress analysis as well as strut-tie approach on concrete solid beams, the non-uniform truss shape of UHSC truss was designed with the architectural esthetic concept. In a series of examples, to compare with conventional concrete members, the proposed UHSC truss members have advantages in capabilities of the slender design with minimum weight with high performances under transverse loadings as well as the aesthetically non-uniform design for spatial structures.

In the current research, a seismic ceiling system as one of non-structural elements in buildings has been developed by applying newly designed vertical hanger clips combined with M-bar channel clips. In order to evaluate the seismic performance of the developed system, full-scale shaking table tests of one story frame structure with the conventional ceiling system or the developed seismic ceiling system were performed with time-history responses under earthquake loads. The developed system was also evaluated by the time-history dynamic analysis. From seismic test and analysis, it was shown that the developed seismic ceiling system could give improved seismic performances to minimize displacements and damages of ceiling systems as well as enhance seismic safety of the ceiling system.

It is known that air pollutants such as fine dust and exhaust gas from vehicles are harmful to human health. In particular, the black carbon emitted by vehicles is known to cause a large number of premature deaths. This study analyzed the effect of a noise barrier on the inflow amount of black carbon from a nearby high traffic road to a school area, using numerical analysis performed at two elementary schools. Also, the correlation between the noise barrier’s shape, height and the inflow amount of black carbon was assessed. As a result, it was found that the higher the noise barrier, the lower the inflow amount of black carbon observed at the school A. However, the inflow amount of black carbon at school B was not greatly influenced by the height of the noise barrier. The inflow amount of black carbon at the schools could be changed not only by the height of the noise barrier, but also by the shape, height and position of the noise barrier and the school building.

본 연구에서는 일반적으로 사용되는 직사각형 부재 대신 초고강도 콘크리트를 적용하여 비정형 형상으로 제작된 구조부재를 설계 하였다. 비정형 형상으로 부재를 실험체를 제작하기 위해 80-200MPa의 높은 압축강도, 10-20MPa 인장강도와 1.0-5.0%정도의 고인성인장변형률을 가진 초고강도 콘크리트를 사용하였다. 또한 정확한 비정형 형상을 제작하기 위해 비정형 거푸집 기술을 새롭게 고안하여 적용 검토하였다.

This research presents one of new architectural SUPER concrete structural members which were designed with nonuniform curvilinear shapes. SUPER concrete had the compressive strength of 80MPa to 200MPa, the tensile strength of 8MPa to 20MPa, and had high ductile tensile strains. Nonuniform concrete formwork were invented and specimens were manufactured to verify by test.

In this research, new structural design and manufacturing method of atypical irregular UHPC structural members were newly introduced. The atypical irregular UHPC member was optimized to design from the conventional rectangular section and a method of nonuniform formwork system was newly created to manufacture the irregular member. The specimens were evaluated by analysis and the newly designed member was improved in bending performance by 2.6 times compared to conventional rectangular concrete beams.

It was studied structural design of nonuniform UHPC concrete structural members. UHPC concrete has the compressive strength of 120-200MPa, the tensile strength of 8-20MPa, and the tensile strain of 1.0-5.0%. There are two types of specimens of nonuniform members improved in bending and shear performances. The specimens were evaluated by beam load test induced by bending and shear failures.

This research was introduced new structural design of atypical irregular beams by applying UHPC which has the compressive strength of 80-200MPa, the tensile strength of 10-20MPa, and strain of 1.0-5.0%. There beam specimen were smaller than actual member in building and new forms created to construction the specimens. The specimens evaluated and the newly irregular beams could improve bending performance by 2.56 times compared to the conventional RC beams.

This research was studied on seismically strengthened RC columns with Strain Hardening Cementitious Composites(SHCC). The seismic performance of the SHCC-RC composite columns in SDOF system was evaluated by the concepts of seismic performance-based design approaches; the Capacity Spectrum Method(CSM), the Direct Displacement Based Design(DDBM) and the Displacement Coefficient Method(DCM).

The research was introduced a newly atypical beam with ultra-high strength concrete. Ultra high strength concrete has compressive strengths up to 200MPa, tensile strengths up to 20 MPa and tensile strain up to 5%. A series of the developed beams was designed an irregular cross-section by precast and form-work technologies. They evaluated the flexural performance by experiment and analysis comparing with conventional reinforced concrete beams.

Ultra high strength concrete was introduced into architectural members. The current ultra high strength concrete can achieve compressive strengths up to 200 MPa and tensile strengths up to 20 MPa. In this study, the flexural and shear strengths in precast structural beams using ultra high strength concrete are evaluated and compared with reinforced concrete beams. This paper also provide a design flexural strength formula for the developed members.

The research presents a reinforced concrete columns using Strain Hardening Cementitious composites (SHCC). For the columns, in order to predict seismic performances, several methods are evaluated in SDOF systems such as the Capacity Spectrum Method (CSM), the Direct Displacement Based Design (DDBM) and the Displacement Coefficient Method (DCM).

In the research, there were seismically strengthened reinforced concrete composite columns by applying Strain Hardening Cementitious Composites(SHCC). The seismic performance of SHCC-RC composite columns were studied by the concepts of seismic performance-based design approaches as well as with experiments.

In this research, it is shown a nonlinear analysis of reinforced concrete (RC) composite columns by applying high-performance fiber-reinforced cementitious composite(HPFC) mortar. The developed model was considering the high-ductile characteristic of HPFC mortar. In the result, the analysis by the model was well predicted the experimental behaviors the RC composite column.

In this study, a newly developed reinforced concrete (RC) composite column strengthened by high performance fiber reinforced composite (HPFC) was analyzed by using a nonlinear flexural analysis of columns. The analysis by the developed model was well predicted the experimental performances of HPFC and RC composite columns.