Four fungal species, during indoor air monitoring for fungi that possibly affect the field testing of a newly bred shiitake cultivar in cultivation houses located in Cheongyang, Chungnam Province and Jangheung, Jeonnam Province. Of these species, two are known to be plant pathogens and the other two are saprobes but potent contaminators in the mushroom cultivation environment. This study reports the morphological characteristics and phylogenetic relationships of these four species based on nucleotide sequences of the internal transcribed spacer (ITS) and 18S rDNA region, including their known information.
본 연구는 교육현장에서의 변혁적 리더십이 교사의 일터영성(workplace spirituality)과 교사가 업무 및 학교생활을 통해 얻어지는 만족도와 학교조직과 학생 및 수업에 대한 애착의 정도를 나타내는 교사헌신 간에 미치는 영향에 대해 실증분석을 통하여 검증하는데 목적이 있다. 이를 위하여 전국의 초·중·고등학 교에 근무하는 교사들을 대상으로 설문지 409부를 회수하여 확인적 요인분석과 구조모형방정식을 이용하 여 분석을 수행하였다. 연구결과, 첫째, 학교장의 변혁적 리더십은 일터영성에 통계적으로 유의미한 정(+)적인 관계를 보이는 것으로 나타났다. 둘째, 일터영성은 소명의식을 제외하고는 교사만족 교사헌신에 모두 통계적으로 유의미한 정(+)적인 관계를 보이는 것으로 나타났다. 셋째, 일터영성은 학교장의 변혁적 리더십과 학생수업 헌신 간에는 완전매개 하는 것으로 나타났으며, 학교장의 변혁적 리더십과 교사만족 및 조직헌신 간에는 부분 매개 하는 것으로 나타났다. 본 연구는 일터영성이 학교조직성과에 중요한 변인임을 실증분석을 통하여 확인하였으며, 학교장은 교 사의 일터영성을 고양시키기 위하여 변혁적 리더십을 발휘하여 조직의 성과를 높여야 한다는 시사점을 제공하는데 의의가 있다.
Safety accident in Building construction work in the process of preparation and implementation of the insecure human, material status is often caused by combining the reality is that many things. Accident rate is a similar level in the case of Korea and foreign countries than any country in the measures by the higher fundamental prescription is needed. In this paper, construction safety management of subcontracting work and small construction plan to apply through a survey to reach a sensible alternative. I did In conclusion, the educated workers know well, and so on the work schedule then quickly if safety management personnel in disaster will be able to reduce the rate to a miracle appeared.
Membrane bioreactors (MBRs) employ a process of biological treatment that is based on a membrane that has the advantages of producing high-quality treated water and possessing a compact footprint. However, despite these advantages, the occurrence of “fouling” during the operation of these reactors causes the difficulty of maintenance.Hence, in this study, three physical cleaning methods, namely, backwashing, air scrubbing, and mechanical cleaning ball was performed to identify optimum operating conditions through laboratory scale experiments, and apply them in a pilot plant. Further, the existing MBR process was compared with these methods, and the field applicability of a combination of these physical cleaning methods was investigated.Consequently, MCB, direct control of cake fouling on the membrane surface was found to be the most effective. Moreover, as a result of operating with combination of the physical cleaning process in a pilot plant, the TMP increasing rate was found to be – 0.00007 MPa/day, which was 185% higher than that obtained using the existing MBR process. Therefore, assuming fouling only by cake filtration, about one year of operation without chemical cleaning is considered to be feasible through the optimization of the physical cleaning methods.
님(Azadirachta indica) 추출물은 곤충의 식욕, 발달 및 산란 억제 효과가 있다. 이러한 효과는 접촉보다 주로 섭식에 의해서 높게 나타난다. 주요 원예해충인 담배가루이에 대하여 님제제(5,000 ppm azadirachtin)의 경구독성을 분석하였다. Double-parafilm chamber에 0, 5, 10, 50 ppm의 azadirachtin을 함유한 20% 설탕액을 72시간 섭식시켜본 결과 살충율이 12.5, 77.5, 97.5, 100%로 나타났다. 담배가루이 약충이 붙어있는 오이잎을 이용한 single leaf assay 결과 우화율이 87.0, 16.6, 16.1, 6.6%로 감소하였다. 또한, 토마토 시설재배지에 azadirachtin 50ppm 농도로 관주처리를 해 본 결과 잎당 약충 수가 평균 60.3% 감소하였다. 그리고 약 2개월간 육안조사에서 작물의 성장에는 무처리구와 차이가 없었다. 본 시험결과, 님액상제제를 관주처리함으로서 가루이 뿐만 아니라 시설재배지의 다른 흡즙성 해충의 경구독성을 유발함으로서 친환경적 해충방제에 효과적인 방법이라고 판단된다.
PURPOSES: The purpose of this study is to suggest a specific investigation guideline to decide priority of repairing old concrete pavements that pile up substantially.
METHODS : In this study, a principle of division of homogeneous sections was proposed to reflect the characteristics of the pavement reasonably in the specific investigation results. In addition, a checklist and guideline of field investigation were suggested for the old concrete pavement sections, which require inspection toward their durability and structural performance. Furthermore, the items of laboratory test necessary to the old concrete pavement were suggested based on the existing laboratory test considering characteristics of the old concrete pavement. The present condition of the old concrete pavement could be analyzed by the test results.
RESULTS: A method of division of homogeneous sections suitable for the specific investigation of the old concrete pavement was suggested. The proportions of distress severity of pavement sections were compared by distress type to figure out the present state of the old concrete pavement. Scaling, durability cracking (or alkali-silica reaction), and longitudinal spalling were selected as the most severe distress types. The detailed positions of the sections were also suggested. The checklist of the specific investigation was categorized by field survey and laboratory test, and its evaluation criteria were proposed. The three types of the sections of durability cracking (or alkali-silica reaction), bridge connection, and asphalt overlay were selected as the sections of the field survey. The compressive strength, void structure, and chloride penetration depth were suggested as the items of the laboratory test.
CONCLUSIONS : A fundamental level of the guideline was suggested in this study to resolve the problem of old concrete pavement. Appropriate guidelines related to the repair of the old concrete pavement should be provided by performing additional research efforts.
This study was performed to improve the foaming generated in the effluent of wastewater treatment plant from March 2015 to July 2016. The main cause of foaming was air entrainment by an impinging jet and the internal accumulation by the diffusion barrier. Particularly, the foam growth was most active when there is low tide and larger discharge. To solve this problem, we experimented after installing fine mesh screen and the artificial channel device with underwater discharging outlet in the treated wastewater discharge channel and the outlet, respectively. As a result, the effects of foam reduction by devices ranged 85.0~92.0% and 70.7~85.6%, respectively. In addition, the foam and the noise were easily solved, first of all look to contribute to the prevention of complaints. Our device studies were applied to a single wastewater treatment plant. However, it is considered to be able to apply in other similar cases of domestic sewage treatment plants.
Wire rods having various sectional shape are generally used in various applications. In a 2-roll shape rolling process, step-by-step rolling operations are executed repeatedly and the rollers must be changed whenever the sectional shape of wire rod is changed. The frequent changes of the rollers and discontinuous repeated operations are cause various shortcomings such as increase of manufacturing cost and reduction in precision. We had developed a high precision automatic wire rod manufacturing system to reduce these shortcomings in the previous study. In this study, we evaluated the field application performance of the developed system in terms of straightness, thickness deviation, surface precision, tensile and hardness of the wire rod in order to verify the feasibility of the system.
이 연구에서는 현장타설 캔틸레버공법(free cantilever method)을 적용한 PSC(prestressed concrete) 교량에 콘크리트의 장기거동을 고려한 시공 중 계측분석 방법을 제안하였다. 콘크리트 박스 거더의 장기 거동에 따른 응력을 확인하기 위해 온도센서와 변형률계를 함께 설치하고 계측된 데이터를 이용하여 크리프계수를 산출하였다. 또한 크리프계수를 적용한 콘크리트 박스 거더의 시공 중 응력을 분석하고 설치된 온도 센서의 변화 데이터를 비교하여 세그먼트 시공에 따른 연직변위를 분석하였다. 연구결과, 교량의 장기 거동을 고려한 FCM 교량의 시공 중 계측은 레이저 변위계나 처짐계를 사용하지 않고 온도와 변위 데이터만을 이용하여 효율적인 분석이 가능한 것으로 나타났다.
Due to increased demand for remodeling and repair in construction market in recent year, the usage of horse scaffold is increasing in the indoor finish works. Injuries related horse scaffold are mainly caused by poor installation or of careless handling of scaffold. Approximately 300 workers are injuried at construction site every year, it is accounting for about 1.5% of the total construction sector and has increased on a year-to-year trends. But the main contents between national standards and speccifications related to the manufacture and usage of horse scaffolds are mutually inconsistent, In particular, the rules on occupational safety and health standards are the basis for the prevention of industrial injuries, there is no explicit application being made to the horse scaffold commonly used on construction sites. The purpose of this study was to analye the manufacture and usage situations in order to reduce construction injuries that occur at the horse scaffolds. It will be utilized the results of the analysis as the basis data for unifying the major domestic standards and specifications associated with the manufacture and usage of horse scaffold.
PURPOSES : The purpose of this study is to investigate characteristics of crack spacing and crack width and their relationship in continuously reinforced concrete pavement (CRCP) based on the data obtained from long-term field observations. METHODS: The crack spacings and crack widths are measured periodically over 10 years at two different CRCP sections: one with asphalt bond breaker beneath concrete slab, and the other with bonded lean concrete base beneath concrete slab. The effects of steel ratio, type of underlying layer, terminal treatment method, and seasonal temperature change on the crack characteristics are evaluated by analyzing the measured data. RESULTS: The CRCP with lean concrete base shows smaller crack spacings than those of the CRCP with asphalt bond breaker. As the steel ratio increases, both the crack spacing and crack width tend to decrease. The crack width becomes larger as the crack age increases, but once the crack age is over a certain value the crack width tends to converge. When the terminal anchor lug system is not used and the expansion joints are employed at the terminals, the crack spacings and crack widths increase near the terminal sections. The crack spacing and crack width seem to be proportional each other, but not necessarily linearly, and their relationship is more distinguished in the summer when the crack widths become smaller. CONCLUSIONS : The steel ratio, underlying layer type, terminal treatment method, and seasonal temperature change affect the characteristics of cracks and the crack spacing and crack width are related to each other.