• Journal of the Korean Chemical Society
• /
• v.59 no.5
• /
• pp.434-444
• /
• 2015

Inquiry-based experiments provide opportunities to understand scientific knowledge and acquire nature of science. In this study, the difficulties which pre-service teachers experienced in inquiry-based experiment class were investigated and analyzed. Twenty-two pre-service teachers attended course designed as ‘ill-structured inquiry’ for 13 weeks, and researchers investigated their difficulties by questionnaires and interview. They showed difficulties mostly in designing experiment and interpretation and also in understanding inquiry purpose, lack of prior knowledge, confidence in inquiry performance, and understanding of experimental instruments and facilities. As a result, it is necessary to provide opportunities to engage in inquiries and environments to properly instruct pre-service teachers the inquiry ability in college of education.

• Journal of Environmental Science International
• /
• v.25 no.4
• /
• pp.483-490
• /
• 2016

On the basis of conducting a comprehensive investigation to agricultural sightseeing garden landscape resources, we established a evaluation index system of agricultural sightseeing garden landscape resources. From the perspective of experts, comparing the importance of all levels indicators, we obtained the weights of landscape resources evaluation index through using the Analytic Hierarchy Process. The result showed that the descending order of the weights of influence of agricultural sightseeing garden nineteen evaluation index is: reach ability (0.128), safety (0.083), location (0.078), participatory (0.076), cultural value (0.058), ecological conditions (0.057), scenic beauty (0.0505), environmental quality (0.051), featured properties (0.0501), environmental tolerance (0.048), reputation (0.047), environmental capacity (0.045), humanize (0.041), spots configuration (0.034), applicable travel period (0.033), scientific value (0.032), art value (0.031), holistic (0.03), suitability (0.027), it can provide a framework and basis for the planning, management, protection and exploitation of agricultural sightseeing garden landscape resources.

• International Journal of High-Rise Buildings
• /
• v.10 no.4
• /
• pp.299-310
• /
• 2021

External fire spread has the potential to breach vertical compartmentation and violate the fire safety strategy of a building. The traditional design solution to this has been the use of non-combustible materials and spandrel panels but recent audits show that combustible materials are widespread and included in highly complex systems. Furthermore, most jurisdictions no longer require detailing of spandrel panels under many different circumstances. These buildings require rapid investigation using rational scientific methods to be able to adequately classify the fire risk. In this work, we use an extensive experimental campaign of material-scale data to explore the critical parameters driving upward flame spread. Two criteria are outlined using two different approaches. The first evaluates the time to ignition and the time to burnout to assess the ability for a fire to spread, and can be easily determined using traditional means. The second evaluates the preheated flame length as the critical parameter driving flame spread. A wide range of cladding materials are ranked according to these criteria to show their potential propensity to flame spread. From this, designers can use conservative approaches to perform fire risk assessments for buildings with combustible materials or can be used to aid decision-making. Precise estimates of flame spread rates within complex façade systems are not achievable with the current level of knowledge and will require a substantial amount of work to make progress.

• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.283.2-283.2
• /
• 2002

Organochlorine pesticides and polychlorinated biphenyls (PCBs) have been used intensively in agriculture and industry for a long time. They belong to a group of contaminants whose occurrence in the environment is a serious concern to environmental chemists and toxicologists due to their resistance to degradation in the environment as well as their potential toxicity. Also. the lipophilic characteristics of these substances are responsible for their ability to bioaccumulate in tissues and organs rich in lipids of men and animals through food chain. Therefore, the measure of the levels of organochlorine pesticides and PCBs in human tissues are good markers in detemining the extent to exposure and evaluating the hazards. This study was preformed to compare concentrations of organochlorine pesticides(${\alpha}-BHC, {\beta}-BHC, {\gamma}-BHC, {\delta}-BHC$, p.p'-DDT,p.p'-DDD,p.p.'-DDE. endrin. dieldrin. aldrin) and seven marker PCBs(PCB nos. 28. 52. 101. 118. 138. 153. 180) in liver. kidney cortex, lung blood and adipose tissue collected at autopsies of 10men and 10 women using gas chromatography equipped with electron capture detector to express the data on a lipid adjusted basis. From the results, the significant differences in the levels of organochlorines of PCBs between sexes, districts where they had lived and ages were also investigated.

• Journal of The Korean Association For Science Education
• /
• v.32 no.4
• /
• pp.760-774
• /
• 2012

The purpose of this study was to analyze the characteristic of the linguistic interaction according to leadership type of the leader in the scientific inquiry activity groups and examine how leadership factors affect the linguistic interaction within a group. In this investigation, leaders among 12 elementary school students were chosen by considering results of the leadership diagnosis that tested 3 leadership factors: vision and promotion, assignment responsibility, and decision-making. The members of the groups were organized according to scientific inquiry ability and academic achievement; the groups were assigned to perform scientific inquiry activities. The linguistic interaction was largely divided into the cognitive domain and the affective domain for analysis. According to the results, the frequency of linguistic interaction within a group sorted by leadership type is more influenced by the cognitive domain than the affective domain. The highest frequency of linguistic interaction appeared within the group that had vision and promotion type leader. Assumedly, the vision and confidence of the vision and promotion type leader produced such an outcome. While solving the assignments, linguistic interaction in all three groups had more cognitive domain than affected domain. Linguistic interaction in cognitive domain displayed only low level of linguistic interaction in relation to the experiment itself: high level of linguistic interaction barely occurred. In the case of affected domain, active participation appeared more frequently than maintaining the mood: Interactions related to restricting the group members actions to solve the assignment appeared more frequently than those for maintaining the mood.

• Journal of Gifted/Talented Education
• /
• v.13 no.2
• /
• pp.113-130
• /
• 2003

In this study, learning materials that can be applied for web-based distant learning model were developed based on the characteristics of elementary school science in which investigation skills and thinking ability are considered to be important. And the effect of students' activity in a reports on student's investigating and thinking ability was investigated. While designing diverse experimental procedures, the students had. an opportunity to improve their observation attitude and way of scientific thinking. Such improvement was possible, only because the present web-based distant learning model consists of requiring an interaction between the students and a report and evaluation system which can put together such effort. Still, it was acknowledged that, as being in lack of teacher's direct support and supervision, the present web-based distant learning model might be somewhat ineffective in guiding the students in accordance with their own characteristics. For example, the students had a tendency to maintain their basic idea and style even when their reports are individually examined and corrected in terms of the format of the report.

• Environmental Mutagens and Carcinogens
• /
• v.25 no.1
• /
• pp.6-12
• /
• 2005

Many compounds might become activated after absorption of UV light energy. In some cases, the resulting molecule may undergo further biological reaction of toxicological relevance related especially to the photo-carcinogenicity resulting from photo-genotoxicity. However, no regulatory requirements have been issued with the exception of guideline issued by the Scientific Committee of Cosmetology, Commission of the European Communities (SCC/EEC) on the testing of sunscreens for their photo-genotoxicity. Thus, the objectives of this study are to investigate the utility of photo-Ames assay for detecting photo-mutagens, and to evaluate its ability to predict rodent photo-carcinogenicity. Photo-Ames assay was performed on five test substances that demonstrated positive results in photo-carcinogenicity tests: 8-methoxypsoralen (photoactive substance that forms DNA adducts in the presence of ultraviolet A irradiation), chlorpromazine (an aliphatic phenothiazine an a-adr-energic blocking agent), lomefloxacin (an antibiotic in a class of drugs called fluoroquinolones), anthracene (a tricyclic aromatic hydrocarbon a basic substance for production of anthraquinone, dyes, pigments, insecticides, wood preservatives and coating materials) and retinoic acid (a retinoid compound closely related to vitamin A). Out of 5 test substances, 3 showed a positive outcome in photo-Ames assay. With this limited data set, an investigation into the predictive value of this photo-Ames test for determining the photo-carcinogenicity showed that photo-Ames assay has relatively low sensitivity (the ability of a test to predict carcinogenicity). Thus, to determine the use of in vitro genotoxicity tests for prediction of carcinogenicity,' several standard photo-genotoxicity assays should be compared for their suitability in detecting photo-genotoxic compounds.

• Strategy21
• /
• s.34
• /
• pp.93-127
• /
• 2014

During the four years following the sinking of the Cheonan frigate in 2010, the South Korean public opinion has seen changes in four basic ways. First, public polls with respect to the cause of the sinking show that 70% of the people consider North Korea as the culprit, while 20% maintain that it was not an act carried out by North Korea. Second, the opinions relative to the cause of the incident seem to vary according to age difference, generational difference, and educational difference. From 2011, people in their 20s showed 10% increase in regarding North Korea as the responsible party. People in their 30s and 40s still have a tendency not to believe the result of the investigation carried out by the combined military and civilian group. Third, the most prominent issue that arose aftermath of the Cheonan incident is the fact that political inclination and policy preference are influencing the scientific determination of the cause. In other words, scientific and logical approach is lacking in the process of determining the factual basis for the cause. This process is compromised by the inability of the parties concerned in sorting out what is objective and what is personal opinion. This confused state of affairs makes it difficult to carry on a healthy, productive debate. Fourth, rumors, propaganda, and disinformation generated by pro-North Korea Labor Party groups in the internet and SNS are causing considerable impact in forming the public opinion. Proposed Strategy 1. The administration can ascertain public trust by accurately determining the nature of the provocation based on accurate information in the early stages of the incident. 2. Education in scientific, logical, rational methodologyis needed at home, school, and workplace in order toenhance the people's ability to seek factual truths. 3. In secondary education, the values of freedom, human rights, democracy, and market economy must be reinforced. 4. It is necessary for the educational system to teach the facts of North Korea just as they are. 5. Fundamental strength of free democratic system must be reinforced. The conservative, mainstream powers must recognize the importance of self-sacrifice and societal duties. The progressive political parties must sever themselves from those groups that take instructions from North Korea's Labor Party. The progressives must pursue values that are based on fundamental human rights for all. 6. Korean unification led by South Korea is the genuine means to achieve peace in a nuclear-free Korean peninsula. The administration must recognize that this unification initiative is the beginning of the common peace and prosperity in the Far East Asia, and must actively pursue international cooperation in this regard.

• Mycobiology
• /
• v.40 no.2
• /
• pp.100-106
• /
• 2012

Interest in commercial cultivation and product development of Cordyceps species has shown a recent increase. Due to its biochemical and pharmacological effects, Cordyceps militaris, commonly known as orange caterpillar fungus, is being investigated with great interest. Cultivation of C. militaris has been practiced on a large scale in order to fulfill a demand for scientific investigation and product development. Isolates of C. militaris can be easily established from both spores and tissue. For isolation of spores, ascospores released from mature stromata are trapped in sterile medium. Multi-ascospore isolates, as well as combinations of single ascospore strains, are used for production of fruiting bodies. Progeny ascospore strains can be isolated from artificial fruiting bodies, thus, the cycle of fruiting body production can be continued for a long period of time. In this study, we examined fruiting body production from multi-ascospore isolates and their progeny strains for three generations. $F_1$ progeny strains generally produced a larger number of fruiting bodies, compared with their mother multi-ascospore isolates; however, $F_2$ and $F_3$ progeny strains produced fewer fruiting bodies. Optimum preservation conditions could help to increase the vitality of the progeny strains. In order to retain the fruiting ability of the strains, further testing of various methods of preservation and different methods for isolation should be performed.

• Asian-Australasian Journal of Animal Sciences
• /
• v.27 no.9
• /
• pp.1368-1372
• /
• 2014

Several studies arduously reported that gayal (Bos frontalis) is an independent bovine species. The population size is shrinking across its distribution. In Bangladesh, it is the only wild relative of domestic cattle and also a less cared animal. Their body size is much bigger than Bangladeshi native cattle and has prominent beef type characters along with the ability to adjust in any adverse environmental conditions. Human interactions and manipulation of biodiversity is affecting the habitats of gayals in recent decades. Besides, the only artificial reproduction center for gayals, Bangladesh Livestock Research Institute (BLRI), has few animals and could not carry out its long term conservation scheme due to a lack of an objective based scientific mission as well as financial support. This indicates that the current population is much more susceptible to stochastic events which might be natural catastrophes, environmental changes or mutations. Further reduction of the population size will sharply reduce genetic diversity. In our recent investigation with 80K indicine single nucleotide polymorphism chip, the $F_{IS}$ (within-population inbreeding) value was reported as $0.061{\pm}0.229$ and the observed ($0.153{\pm}0.139$) and expected ($0.148{\pm}0.143$) heterozygosities indicated a highly inbred and less diverse gayal population in Bangladesh. Prompt action is needed to tape the genetic information of this semi-domesticated bovine species with considerable sample size and try to investigate its potentials together with native zebu cattle for understanding the large phenotypic variations, improvement and conservation of this valuable creature.