• Journal of The Korean Association For Science Education
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• v.40 no.4
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• pp.399-413
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• 2020

In this study, we analyzed science teachers' NOS-PCK in Science Inquiry Experiment lessons. Four science teachers in charge of Science Inquiry Experiment in high schools located in the Seoul metropolitan area participated in the study. NOS Lessons were observed, all of the teaching-learning materials were collected, and semi-structured interviews were conducted. All the collected data were analyzed according to five factors of NOS-PCK. As a result of the study, their understanding and consideration of the curriculum related to NOS were insufficient in some cases. They thought that given inquiry activities or textbook composition was not effective for NOS teaching so that they actively reconstructed the curriculum. In terms of teaching strategies, their lessons were close to explicit approaches. However reflective approaches were generally lacking. They were neglected in evaluating NOS for reasons that views of NOS are individually subjective or that NOS is not an area of cognitive learning. They guessed the state of students by relying on their own experiences rather than based on evaluation results. They recognized a specific aspect of values of NOS learning. And intention to teach NOS played an important role throughout their classes. Based on the above results, we discuss some ways to improve the professionalism of science teachers for NOS teaching.

• Journal of the Korea Institute of Building Construction
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• v.16 no.4
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• pp.321-329
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• 2016

The use of ternary blended cement consisting of Portland cement, granulated blast-furnace slag (GGBFS) and fly ash has been on the rise to improve marine concrete structure's resistance to chloride attack. Therefore, this study attempted to investigate changes in chloride attack resistibility of concrete through NT Build 492-based chloride migration experiments and test of concrete's ability to resist chloride ion penetration under ASTM C 1202(KS F 2271) when 1.5-2.0% of alkali-sulfate activator (modified alkali sulfate type) was added to the ternary blended cement mixtures (40% ordinary Portland cement + 40% GGBFS + 20% fly ash). Then, the results found the followings: Even though the slump for the plain concrete slightly declined depending on the use of the alkali-sulfate activator, compressive strength from day 2 to day 7 improved by 17-42%. In addition, the coefficient from non-steady-state migration experiments for the plain concrete measured at day 28 decreased by 36-56% depending on the use of alkali-sulfate. Furthermore, total charge passed according to the test for electrical indication of concrete's ability to resist chloride ion penetration decreased by 33-62% at day 7 and by 31-48% at day 28. As confirmed in previous studies, reactivity in the GGBFS and fly ash improved because of alkali activation. As a result, concrete strength increased due to reduced total porosity.

• Clean Technology
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• v.14 no.3
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• pp.171-175
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• 2008

The effect of the addition of $Al^{3+}$ dopant on the electrochemical characteristics of $Li_{4}Ti_{5}O_{12}$ was investigated. $Li_{4}Ti_{5}O_{12}$ is known as a 2ero-strain material, and $Li_{3.95}Al_{0.15}Ti_{4.9}O_{12}$ has been manufactured by solid-state reaction with high energy ball milling (HEBM). The samples were heated at 800, 900 and $1000^{\circ}C$ in electric furnace. The structural and surface structures were measured by XRD (X-ray diffraction) and SEM (scanning electron microscopy). Cut-off voltage of charge/discharge cycles was $1.0{\sim}3.0 V$ to investigate reversible capacity, cycle stability and plateau voltage. The reversible capacity of $Li_{3.95}Al_{0.15}Ti_{4.9}O_{12}$ was 138 mAh/g.

• Resources Recycling
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• v.21 no.1
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• pp.30-40
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• 2012

Electric arc furnace slag is made in ironworks during steel refining, it is been increasing chemical and physical resistibility using ageing method of unstable state of melting steel slag for using concrete's fine aggregates. Which is been changing stable molecular structure of aggregates, it restrains moving of ion and molecule. In Korea, KS F 4571 has been prepared for using the electric arc furnace oxidizing slag to concrete aggregates(EFS). In this study, Electric arc furnace oxidizing slag is used in the PRCC(Polymer Rapid setting Cement Concrete) which is applied a bridge pavement of rehabilitation, largely. The results showed that the increment of compressive strength development by 10- 20%. The flexural strength of EFS-Con increased greatly as the electric arc furnace oxidizing slag changed. The compressive strength and flexural strength developed enough for opening the overlayed EFS-Con to the traffic after 4 hours of EFS-Con placement. The permeability of EFS-Con was evaluated as negligible due to its very low charge passed. Thus, EFS-Con could be used at repairing or overlaying the concrete at fast-track job sites.

• Korean Chemical Engineering Research
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• v.59 no.1
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• pp.42-48
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• 2021

Zn and Al added LiNi0.85Co0.15O2 cathode materials were synthesized to improve electrochemical properties and thermal stability using a solid-state route. Crystal structure, particle size and surface shape of the synthesized cathode materials was measured using XRD (X-ray diffraction) and SEM (scanning electron microscopy). CV (cyclic voltammetry), first charge-discharge profiles, rate capability, and cycle life were measured using battery cycler (Maccor, series 4000). Strong binding energy of Al-O bond enhanced structure stability of cathode material. Electrochemical properties were improved by preventing cation mixing between Li+ and Ni2+. Large ion radius of Zn+ increased lattice parameter of NC cathode material, which meant unit-cell volume was expanded. NCZA25 showed 80% of capacity retention at 0.5 C-rate during 100 cycles, which was 12% higher than that of NC cathode. The discharge capacity of NCZA25 showed 104 mAh/g at 5 C-rate. NCZA25 achieved 36 mAh/g more capacity than that of NC cathod. NCZA25 cathode material showed excellent rate capability and cycling performance.

• Journal of the Korean Chemical Society
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• v.65 no.6
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• pp.433-440
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• 2021

Surfactants are organic compounds that have both hydrophilic and non-polar parts in one molecule, classified as non-ion, anion, cation, and amphoteric surfactants according to the charge of hydrophilic parts in aqueous state. A trace amounts may remain when vegetables and fruits are washed using type1 detergent (Vegetable and fruit detergent), and there is a possibility of exposure to the human body through ingestion. This study developed the simultaneous analysis method for 5 surfactants with LC-MS/MS for analysis of detergent residues after washing vegetables and fruits with detergent. The mobile phase used distilled water and acetonitrile containing 50 mM ammonium formate and 0.1% formic acid and was analyzed using a gradient method using XBridge BEH C8 column. The accuracy of the established method was 83.9-112.1%, and the precision was less than 20%. The detection limit was 7.0 (SLS) to 29.0 (SLES-N3) ㎍/L, and the correlation coefficient (r²) of calibration line regression was greater than 0.99, it is considered suitable for the analysis of trace amounts of surfactant components remaining in vegetables and fruits.

• Land and Housing Review
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• v.5 no.1
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• pp.11-24
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• 2014

The expected launching countries are selected based on the state and strategy of businesses undertaking by LH, then the legal systems for urban development of those countries are investigated and analyzed to be used as basic data for advancing to oversea urban development. The results are showing as follows. First, on the basis of the advancing priority, and the level and obtaining possibility of legal system for urban developments, Bangladesh, Thailand, Dominican Republic, and Venezuela are selected to be investigated among the countries of Central and South America and Asia to where expected to be advanced. Second, most of the selected countries establish and promote the national housing policies by their own National Housing Authority. For example, First-Home Policy and National Housing Development Strategy, etc. are established in Thailand, and National Housing Authority takes charge of the housing development for low-income bracket. Third, the laws and project procedures are investigated, then compared to the similar laws of Korea. The common "Land Allocation Act" is legislate in Bangladesh and Thailand, for example, "Land Allocation Act" and "Town and City Planning Act" are enacted in Thailand. On the other hand, the laws for urban and housing developments vary from country to country those are located in Central and South America. Meanwhile, it is verified that "Act on Planning and Use of National Territory" of Korea is similar to the "Town and City Planning Act" of Thailand.

• The Korean Journal of Rehabilitation Nursing
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• v.4 no.2
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• pp.179-186
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• 2001

The purpose of this study is to develop a systematic and efficient curriculum for the rehabilitation nurse specialist program. This research was carried out as a group work of 15 experts in order to share various opinions about the curriculum, and also through literature review. Articles, curriculums of other Clinical Nurse Specialist Programs, medical laws guidelines, as well as Clinical Nurse Specialist Program from the Korean Nurses Association were reviewed, and the issue was discussed throughly via group meetings. The developed curriculum is as follows: 1. Educational philosophy lies in the fact that the rehabilitation nurses support the patients to maximize their potential and functional level, so that they could maintain healthy state and re-adapt to changed environment. Furthermore the rehabilitation nurses are disposed of arbitrary decision power under their own responsibility, thus they take charge of welfare and healthy environment of the local society through the patients(subjects) and local resources. 2. Educational goals are to train rehabilitation nurse specialist, who correspond to the social needs, so to say, those who have the knowledge and skills for nursing practice, education and research. 3. The curriculum consists of 37 credits, of which 24 credits are based on lectures and 13 credits based on clinical practice. General courses are 3 subjects (5 credits) ; nursing theory, nursing research, and laws/ethics. Mandatry courses are 8 subjects with 19 credits; advanced physical assessment, pharmacology, pathophysiology, issues in rehabilitation nursing, advanced rehabilitation nursing intervention I, advanced rehabilitation nursing intervention II, sports physiology, special rehabilitation nursing intervention. As for the clinical practice courses, assessment and evaluation for rehabilitation(64 hours), community and home based rehabilitation nursing(128 hours), hospital based rehabilitation nursing(128 hours), institution based rehabilitation nursing(96 hours) would be treated. 4. Contents of the curses were developed to correspond with the courses' objectives and specific items. 5. Evaluation would be carried out both in the lecture and in the clinical practice. The knowledge and skills of the students would be measured to ensure full validity and credibility. However this developed curriculum should be continuously modified and updated in more desirable direction.

• Journal of the Korean earth science society
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• v.28 no.2
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• pp.240-247
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• 2007

Geological information can be used for various purposes, such as the mine development, landuse, environmental protection, construction industry, and the development of water resource. Although geological information is highly useful for developing industrial raw materials, national land management and people's welfare, there is no unified public institution in charge of collecting and managing geological information at the national level. Thus, the government is to collect geological information, to construct database and to utilize and to distribute the information in a long-term and systematic way, the purpose of this study is to propose strategies for establishing an integrated geological information management system. In this study, we A) analyzed the current state and management of geological information in Korea and other countries; B) surveyed demand for geological information and analyzed correlations; C) drew up a conceptual diagram of the national integrated geological information management system; and D) developed strategies for establishing the national integrated geological information management system.

• Korean Security Journal
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• no.45
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• pp.7-35
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• 2015

South Korea's socioeconomic status is high enough to support services for the protection of crime victims. Until now, the Ministry of Justice was the only institution to protect and support the victims, but recently the national police is included. This is considered preferable, since the police is the one to contact the victims first- they can provide immediate support after the incident. Several limits in current laws and crime protection system exist. Therefore, given the importance of protecting victims, model of public-private joint forms should be considered. In premise of establishing a new relationship between the public-private joint system of justice and the maintenance, the range of police's involvement with crime supports will be determined. In the case of developed countries, the police and private organizations maintain close cooperation, appearing as substantial care and support for crime victims. Therefore this study reviews the problems in crime victim protection, assistance from the police stage, and suggest the improvements as follows. The first is to redefine the role of the police who first contacted in the crime victims protection support, the second is to establish a permanent cooperation framework, such as victims specialized police, victims protection agency, the third is to develop services for victim protection available from the police stage, and the fourth, opening Victim Support Center functioning as a temporary accommodation or safety zone for the personal protection of victims. The fifth is to regularize solution conference for victims' protection, and the sixth is to divide of roles in state organization government in charge of victim's protection and local government responsible for victim's support.