• Journal of The Korean Association For Science Education
• /
• v.16 no.1
• /
• pp.1-12
• /
• 1996

The purpose of this study is to investigate the psychological hierarchy structure of science concepts and to determine the effective teaching order by comparing the teaching effects of the psychological hierarchy order with those of teaching order of the current text in order to inquire validating evaluation framework of science curriculum sequence. Key concepts were selected by tasks analysis in the seven units of elementary and secondary school curriculum. Concept formation tests were developed to evaluate each concepts achievement,. The test items were made according to each of the concepts based on 12 prototype tasks developed by Frayer(1969). To identify the students' psychological hierarchy the test items were administrated to elementary and secondary school students. Ordering theory was used to identify the students' psychological hierarchy. Nonequivalent control group pretest-posttest design was used in this study as an experimental design. Teaching with psychological hierarchy order was applied tp experimental group and teaching with concept order described in the current text was applied to control group. The major results of this study are as followings: 1. The students' psychological hierarchy structures are different from logical hierarchy structures. 2. The science teachers' psychological hierarchy structures are different from not only logical hierarchy structures but also students' psychological hierarchy structures. 3. The mean score of experimental group applied psychological hierarchy order is significantly higher(p<.05) than the control group in the concept achievement.

• Korean Journal of Veterinary Service
• /
• v.33 no.1
• /
• pp.13-21
• /
• 2010

Chicken anemia virus (CAV) has been recognized as an immunosuppressive agent and plays role as an etiological agent of multifactorial diseases in chicken. In this study, we investigated distribution of CAV antibody by ELISA and the virus gene by PCR in poultry farms in Jeongeup, Jeonbuk province. In the test using ELISA kit, 41 (95.3%) of 43 flocks and 88.6% of the individual chickens were positive, respectively. By PCR, 90.9% of the broiler breeders and 75.0% of White-semi breeders were found positive, respectively. All hatchery was negative by PCR. Of the clinical cases from 49 poultry flocks, 87.5% of flocks and 54.7% for each samples were found positive by ELISA, respectively. By PCR test, 21 (42.9%) of 49 flocks were positive. Major clinical signs of the infected flocks were growth retardation, femoral subcutaneous bleeding, depression, limping, and continuing selection. The genetic analysis of separate N genes of CAV showed highly homologous each other. The nucleotide sequence of field isolates had homology ranged from 99.9% to 97.5% with Chinese strains, and 99.9% to 99.6% with Japanese strain. Phylogenetic analysis based on the N gene of CAV isolates showed the closely relation with Chinese strains. The results of this survey could be used as basic data for development of vaccine.

• Korean Journal of Occupational Health Nursing
• /
• v.8 no.2
• /
• pp.162-168
• /
• 1999

To investigate industrial fatigue and low back pain, the questionaire survey for subjective symptoms of fatigue and low back pain was carried out 305 nurses in general hospital in Korea. Nurses participated to this study were divided into low back pain group(LBP) and control group, according to the self-reports by written questionaires. The subjective sysptoms of fatigue comprised three groups of 10 items each, representing dullness and sleepiness(level of cerebral activation), difficulty in concentration(level of motivation) and bodily projection of fatigue. The resultant data were processed for $x^2$-test, t-test to confirm the associations. The results were as follows: 1. 28 items of fatigue subjective symptoms exept two item, 'feel thirsty and 'feel ill', were directly associated with low back pain. 2. The percentage of fatigue complaint were significantly higher in LBP group than control. 3. Of the 30 items of fatigue subjective symptoms, the highest percentage was accounted for 'legs feel heavy', 'eye strain', 'feel stiffness in the neck or the shoulders' followed by 'feel like lying', 'whole body feels tired', 'feel a pain in the low back', 'feel drowsy' and in the order of sequence. 4. The average weighted score for the first group of fatigue items(dullness and sleepiness) was the largest among three groups and was followed by the second group(difficulty in concentration) and the third group (bodily projection of fatigue) in the order of sequence, suggesting the heavier mental and shift work stress of the female workers.

• Research in Plant Disease
• /
• v.29 no.4
• /
• pp.377-383
• /
• 2023

In 2020 and 2021, we surveyed diseases of three-leaf ladybell (Adenophora triphylla) plants grown in fields at two locations in Korea. During the disease surveys, severe leaf rot symptoms were observed on the young plants in Hongseong, and stem rot symptoms on the adult plants in Cheolwon. The incidence of leaf rot was 5-60%, and that of stem rot 1-10%. We obtained 6 fungal isolates each from the leaf rot lesions and the stem rot lesions. All the isolates were morphologically identified as Rhizoctonia solani. Anastomosis test and investigation of cultural features of the fungal isolates revealed that the isolates from the leaf rot lesions corresponded to R. solani AG-1(IB), and those from the stem rot lesions to R. solani AG-2-2(IIIB). Two isolates each of R. solani AG-1(IB) and AG-2-2(IIIB) were used for DNA sequence analysis and pathogenicity test to three-leaf ladybell plants through artificial inoculation. The anastomosis groups and cultural types of the R. solani isolates were confirmed by the sequence analysis. The pathogenicity tests revealed that the isolates of R. solani AG-1(IB) caused only leaf rot symptoms on the inoculated plants, and those of R. solani AG-2-2(IIIB) leaf rot and stem rot symptoms. The induced symptoms were similar to those observed in the fields investigated. Leaf and stem rot of three-leaf ladybell caused by the two anastomosis groups and cultural types of R. solani is first reported in this study.

• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.741-743
• /
• 2004

In this paper, we describe a Control Element Drive Mechanism(CEDM) operation test using a Power Controller. By testing, we can catch the mechanical and electrical characteristics of CEDM and obtain the information about the improvement of CEDM and the design of CEDM power cabinet. The power controller for CEDM introduced in this paper can input firing angles directly into gate drive circuits of thyristors so that this method can be used to derive the maximum and minimum values of firing angles within available limits for a 3-phase half-wave rectifier. Angle inputs help us understand each coil's response characteristics. Since this power controller generates a serial sequence for CEDM insertion and withdrawal operations, we may judge whether CEDM works correctly as expected or not in each phase of a step movement.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 1997.04a
• /
• pp.107-112
• /
• 1997

In this study of made Autmation system is moving linear transfer system for mainly forming of small electronic unit and other at press line. This system for loading and unloading a workpiece has been installed in a press in order to load and unload a workpiece from a press die. Main Control method be used PLC. It took data of input from each sensor and send signal of output to actuator by sequence program also, we try to Characteristics test of this system has good condition when operating with raser measurmant.

• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.1
• /
• pp.159-171
• /
• 2003

In this paper, same parts of a domestic automobiles and foreign automobiles are disassembled fur the evaluation of disassemblability, especially door trim and bumper. Influencing factors of disassembly are determined by the classification of bottleneck process in disassembly process. On the bases of disassembly sequence and structure of parts and subassembly, disassemblability is classified into aye categories. The influencing factors, which are related with the five categories are determined. By these relations, the checklist for disassembly evaluation is draw up and score tables of checked factors are established. For the establishing the disassembly score tables, the weighting values of each five categories are calculated by the disassembly test of automobiles and then, the weighting values of each influencing factors of five categories are calculated by the method of AHP (Analytic Hierarchy Process). And the last, the weighting values are modified and recalculated from the disassembly test. Using these weighting values, the score of influencing factors are determined and then, the score tables are established based on the score of influencing factors.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.11b
• /
• pp.636-640
• /
• 2002

Acoustic coupled combustion instability, which is one of the most undesirable phenomena in the development of liquid propellant rocket engine, can cause serious damage to a rocket itself, and must be avoided by all means. Unfortunately, KSR-III rocket went through combustion instability during engine start at the propulsion test article No.2. To resolve the problem, time sequence (cyclogram) has been changed, and baffle system has been applied. In consequence of change, stable combustion was achieved.

• Communications for Statistical Applications and Methods
• /
• v.10 no.3
• /
• pp.955-969
• /
• 2003

The classical Fourier analysis, which is the typical frequency domain approach, is used to detect periodic trends that are of the sinusoidal shape in time series data. In this article, using a sequence of periodic step functions, describes an adaptive Fourier series where the patterns may take general periodic shapes that include sinusoidal as a special case. The results, which extend both Fourier analysis and Walsh-Fourier analysis, are applies to investigate the shape of the periodic component. Through the real data, compare the goodness-of-fit of the model using two methods, the adaptive Fourier method which is proposed method in this paper and classical Fourier method.

• Journal of the Korea Society for Simulation
• /
• v.5 no.2
• /
• pp.13-24
• /
• 1996

Workflow is an ordered sequence of interdependent component data activities each of which can be executed on an integrated information system by accessing a remote information system. In our previous research [4], we proposed a distributed CIM Workflow system which consists of a workflow execution model called DAF-Net and an agent-based information systems called AIMIS. Given a component data activity, there needs an interaction protocol among agents which allocates the component data activity to a relevant information systems exist. The objective of this research is to propose and test two protocols: ARR(Asynchronous Request and Response)protocol and NCL(Negotiation with Case based Learning) protocol. To test the effectiveness of the protocols, we applied the PVM(Parallel Virtual Machine) software to simulate the distributed CIM Workflow system. PVM provides a distributed computing environment in which users can run different software processes in different computers while allowing communication among the processes.