• Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.240-255
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• 2024

Widas Reservoir is situated in an area of 570 ha in the Pajaran Village, Madiun Regency, East Java Province, Indonesia, playing an essential role in fisheries, with the average fish catch per year of about 283 tons/year. This study explores the standing stock, growth parameters, mortality, and exploitation rates of several dominant fishes in Widas Reservoir. This study was carried out from February to November 2019. Fish stocks were estimated using acoustic tools, fish catch records, and sizes collected by local enumerators. Fish length frequency sampling was conducted on several dominant fish species, such as Oreochromis niloticus, Barbonymus gonionotus, and Osteochilus vittatus. Based on the length-frequency data, estimating fish population dynamics, the fish population dynamics (infinitive length (L_∞) and growth coefficient (K)) estimation was run in a time series using the Fish Sock Analysis Tool, II (FISAT II) program package. Moreover, the estimation of natural mortality parameters, the fishing mortality parameter, and the exploitation rate was also performed. The approximated overall fish stock in the Widas Reservoir was about 79,848 kg, which lowered with the increase in water depth. Of particular concern, in the surface layer at a depth between 1-5 m, the fish stock reached 58,813 kg, while in the deeper zone (> 15 m), the value significantly lowered by about 98%, reaching 1,219 kg. These results indicate an overfishing in the Widas Reservoir. The value of the exploitation rate (E) of B. gonionotus was 0.748, O. niloticus 0.8, and O. vittatus 0.7, respectively, proving the overfishing states occurred in the study area. Therefore, regulations governing the number of catches and the use of fishing gear are crucial in Widas Reservoir, particularly the use of lift and gill nets with a mesh size of less than 2 cm.

• Journal of the Health Care and Life Science
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• v.11 no.2
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• pp.341-349
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• 2023

This study analyzed the impact on entrepreneurship, passion, and start-up execution willingness to start a business for 200 prospective start-ups in Jeollanam-do. As a result of this study, it was found that there was an effect at the statistically significant level (p<.05) in the relationship between the start-up support program and start-up willingness. In the mediating effect analysis of passion for entrepreneurship support programs, it was confirmed that passion played a complete mediating role in the relationship between mentoring and start-up willingness and a partial mediating role in the relationship between the start-up support fund and start-up willingness. In the analysis of the mediating effect of passion on entrepreneurship, it was confirmed that passion played a partial mediating role in the relationship between initiative and start-up execution willingness, and also in the relationship between risk sensitivity and start-up execution willingness. This shows that when proper initiative and risk tolerance are recognized, passion enhances the start-up willingness to run into the start-up market. Based on these results, we suggested theoretical implications and policy support directions to increase the willingness of prospective founders to implement.

• Communications of Mathematical Education
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• v.38 no.3
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• pp.331-351
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• 2024

The purpose of this study is to examine the effects of taking a 「Theory of mathematical education」 on the mathematical beliefs of pre-service teachers. For this theory of mathematical education was run in the first semester of 2021 and 2022, and the data was collected and analyzed by conducting a mathematical beliefs questionnaire, drawing a mathematics class scenes test, and focus group interviews with participants. According to the results of the study, there was a statistically significant difference between the pre-test and post-test results on the 'process of inquiry' of the nature of mathematics and the 'active participation' of mathematics learning in the mathematical belief category of pre-service teachers. In addition, in the image test of mathematics classes, the proportion of the image of the student-centered class increased significantly in the post-test compared to the pre-test, while the proportion of the image of the teacher-centered class decreased significantly. It can be assumed that the various learning opportunities provided in the pre-service mathematics teacher education program promoted the composition of practical knowledge based on propositional knowledge of pre-service teachers, and this series of processes contributed to transforming the mathematical beliefs of pre-service teachers into learner-centered beliefs.

• Journal of Public Diplomacy
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• v.3 no.1
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• pp.43-63
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• 2023

Objectives: Nuclear security and atomic energy industry have always been the domain of political and economical diplomatic affairs. The issue of nuclear proliferation must be resolved politically or militarily given the importance of the problem, the impact it has on global security, the influence of major powers, and non-proliferation regimes. Considering scope of the budget, manpower, and scale of the project, the atomic energy issue was also viewed from an economic perspective. Therefore, the goal of this study is to depart from the conventional viewpoint and investigate if public diplomacy may be extended to a new issue domain of nuclear security and atomic energy. Methods: In order to determine whether there are any areas that overlap, the uniqueness of Korea's position in the nuclear security and atomic power domains is evaluated and compared with the traits of public diplomacy. Results: It seems plausible to broaden the scope and function of public diplomacy in that field given Korea's uniqueness in nuclear security and atomic energy issue and overlap with public diplomacy. This is especially true given that the state must take the leading role and that ongoing policy demands are made in light of Korea's security and economic structure. In reality, it is assessed that the Summer Fellows Program, run by the KAIST Nuclear Nonproliferation Education and Research Center (KAIST NEREC), has had a considerable impact on public diplomacy in the area of nuclear security and atomic energy. Conclusions: Nuclear security and atomic energy issues have traditionally been handled from the perspectives of political diplomacy, summit diplomacy, and economic diplomacy. However, this paper evaluate that the possibility of enhancing the role of public diplomacy in this issue area is high and underscore that the budget support, programs, and manpower for similar public diplomacy activities are needed. Through this, South Korea's nuclear security policy and atomic energy industry could be supported from international community and it will advance national interest.

• Applied Chemistry for Engineering
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• v.35 no.5
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• pp.385-389
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• 2024

For high-purity purification of indole (IN) contained in crude methylnaphthalene oil (CMNO), this study was reviewed by adopting the re-extraction method using n-hexane as an enrichment method of IN contained in the extract phase recovered from equilibrium extraction of CMNO and formamide aqueous solution. The raw material (extract phase) contained three types of nitrogen-containing compounds (NCCs): quinoline (QU), isoquinoline (IQU), and IN; and four types of bicyclic aromatic compounds (BACs): naphthalene, 2-methylnaphthalene, 1-methylnaphthalene, and biphenyl (BP). The distribution coefficient and selectivity of IN showed almost constant values regardless of the change in the initial volume fraction of the re-extraction solvent to the raw material. Compared to the distribution coefficient of IN, those of two types NCCs excluding IN and three types BACs excluding BP, respectively, are about 4~7 times and 190~394 times higher. In addition, the concentration of IN in the raffinate oil recovered through equilibrium n-hexane re-extraction run of the batch co-current five-stage under constant re-extraction was 54.6%, which was approximately 2.5 times higher than that of the raw material. From the excellent IN enrichment efficiency of this study, the re-extraction method using n-hexane was expected to be a new IN enrichment method that can be an alternative to the distillation method.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.9 no.2
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• pp.227-236
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• 1998

Objectives：Conduct disorder is one of the most frequent diagnosis in outpatient and inpatient mental health facilities for children and adolescents. This study investigated the clinical characteristics of children and adolescents with conduct disorder. Methods：The study employed a retrospective review of 45 inpatients diagnosed with conduct disorder by DSM-IV criteria at SNUH Child Psychiatric Unit from 1993, March to 1998, September. Results：The results were as follows：1) The sex ratio was 2：1, male dominant. Mean age on admission was $12.8{\pm}2.4$ years old(male：$12.2{\pm}2.3$, female：$14.1{\pm}2.1$). The mean age of male subjects was significantly lower than that of female subjects(p<.05). 2) We classified all subjects according to child- or adolescent-onset type by DSM-Ⅳ. Childhoodonset type was 42.2%, and adolescent-onset, 57.8%. The onset of male subjects were significantly earlier than that of female subjects(p<.05). 3) The most common complaint was 'serious violation of rules'(77.8%) by DSM-Ⅳ dimensions, while the most common single symtom was 'run away from home overnight at least twice while living in parental or parental surrogate home'(48.9%). 4) The comorbid psychopathology of the subjects were frequently described as follows, in order of frequency：substance use(42.2%), ADHD(35.6%), depression(20.0%), tic disorder(11.1%), bipolar disorder(4.4%). 5) On MMPI, both Pd and Ma subscales got the highest scores. The mean of total IQ by KEDIWISC was $100.0{\pm}15.1$. Female subjects' IQ was higher than that of male subjects. 6) Regarding the number of visits to the OPD after discharge, many subjects(33.3%) had visited OPD fewer than four times. Conclusions：In this study, the male to female ratio of adolescent type showed a decreasing trend. An interesting finding was the fact that socio-economic circumstances, as well as the level of education among patients, were higher than those of previous studies. The subjects' problem were also principally self contered and posed no threat to others.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.8
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• pp.367-376
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• 2007

In this paper, we introduce an application-specific and adaptive power management technique for portable systems that support dynamic voltage scaling (DVS). We exploit both the idle time of multitasking systems running soft real-time tasks as well as memory- or CPU-bound code regions. Detailed power and execution time profiles guide an adaptive power manager (APM) that is linked to the operating system. A post-pass optimizer marks candidate regions for DVS by inserting calls to the APM. At runtime, the APM monitors the CPU's performance counters to dynamically determine the affinity of the each marked region. for each region, the APM computes the optimal voltage and frequency setting in terms of energy consumption and switches the CPU to that setting during the execution of the region. Idle time is exploited by monitoring system idle time and switching to the energy-wise most economical setting without prolonging execution. We show that our method is most effective for periodic workloads such as video or audio decoding. We have implemented our method in a multitasking operating system (Microsoft Windows CE) running on an Intel XScale-processor. We achieved up to 9% of total system power savings over the standard power management policy that puts the CPU in a low Power mode during idle periods.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.65-71
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• 2011

Purpose: The recently adopted multiple confocal SPECT SYSTEM (hereinafter called IQ SPECT$^{TM}$) has a high difference from the conventional myocardial perfusion SPECT in the collimator form, image capture method, and image reconstruction method. This study was conducted to compare this novice equipment with the conventional one to design a protocol meeting the IQ SPECT, and also determine the characteristics and usefulness of IQ SPECT. Materials and Methods: 1. For the objects of LEHR (Low energy high resolution) collimator and Multiple confocal collimator, $^{99m}Tc$ 37MBq was put in the acrylic dish then each sensitivity ($cpm/{\mu}Ci$) was measured at the distance of 5 cm, 10 cm, 20 cm, 30 cm, and 40 cm respectively. 2. Based on the sensitivity measure results, IQ SPECT Protocol was designed according to the conventional general myocardial SPECT, then respectively 278 kBq/mL, 7.4 kBq/mL, and 48 kBq/mL of $^{99m}Tc$ were injected into the myocardial and soft tissues and liver site by using the anthropomorphic torso phantom then the myocardial perfusion SPECT was run. 3. For the comparison of FWHMs (Full Width at Half Maximum) resulted from the image reconstruction of LEHR collimator, the FWHMs (mm) were measured with only algorithms changed, in the case of the FBP (Filtered Back projection) method- a reconstruction method of conventional myocardial perfusion SPECT, and the 3D OSEM (Ordered subsets expectation maximization) method of IQ SPECT, by using $^{99m}Tc$ Line source. Results: 1. The values of IQ SPECT collimator sensitivity ($cpm/{\mu}Ci$) were 302, 382, 655, 816, 1178, and those of LEHR collimator were measured as 204, 204, 202, 201, 198, both at the distance of 5 cm, 10 cm, 20 cm, 30 cm, and 40 cm respectively. It was found the difference of sensitivity increases up to 4 times at the distance of 30 cm in the cases of IQ SPECT and LEHR. 2. The myocardial perfusion SPECT Protocol was designed according to the geometric characteristics of IQ SPECT based on the sensitivity results, then the phantom test for the aforesaid protocol was conducted. As a result, it was found the examination time can be reduced 1/4 compared to the past. 3. In the comparison of FWHMs according to the reconstructed algorithm in the FBP method and 3D OSEM method followed after the SEPCT test using a LEHR collimator, the result was obtained that FWHM rose around twice in the 3D OSEM method. Conclusion : The IQ SPECT uses the Multiple confocal collimator for the myocardial perfusion SPECT to enhance the sensitivity and also reduces examination time and contributes to improvement of visual screen quality through the myocardial-specific geometric image capture method and image reconstruction method. Due to such benefits, it is expected patients will receive more comfortable and more accurate examinations and it is considered a further study is required using additional clinical materials.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.299-304
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• 2012

In this work, we experimented with the two-fluid fogging system that eco-friendly prevents whiteflies in greenhouses in order to find the optimal concentration of oleic acid supplied through the system and to evaluate the control value of three consecutive treatments. The first experiment, which was to find the optimal concentration of oleic acid, used "Dotaerang Gold" tomatoes grown in stand-alone plastic greenhouse at Buyeo Tomato Experiment Station. We tested three levels of concentration of oleic acid, which were 0, 2000, and 4000 ppm. The second experiment, which was to evaluate the control value of three consecutive treatments of oleic acid, used "Rokusanmaru" tomatoes grown in Venlo type glasshouse at Gyeonggi-Do Agricultural Research & Extension Services. In this experiment, oleic acid of 2000 ppm was applied three times with two days intervals. The number of whiteflies was counted 2 two days after the last application of oleic acid. Even when oleic acid was not being applied, the two-fluid fogging system was run from 9:00 am to 5:00 pm whenever the temperature is higher than $25^{\circ}C$ or the humidity is lower than 75%. In the first experiment, the control value was 81.6% with 2000 ppm of oleic acid and 93.6% with 4000 ppm. It means that the higher the concentration is, the greater the control value. In the second experiment, 2000 ppm treatment resulted in 85.8% of the control value, which is higher than the required standard for insecticides. Hence, spraying oleic acid with the concentration of 2000 ppm three times with two days intervals turned out to be a very effective in the eco-friendly prevention of whitefly.

• Journal of Biosystems Engineering
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• v.16 no.4
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• pp.384-398
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• 1991

A computer program was developed to select the optimum size of farm machine and analyze its operation costs according to various farming conditions. It was written in FORTRAN 77 and BASIC languages and can be run on any personal computer having Korean Standard Complete Type and Korean Language Code. The program was developed as a user-friendly type so that users can carry out easily the costs analysis for the whole farm work or respective operation in rice production, and for plowing, rotarying and pest controlling in upland. The program can analyze simultaneously three different machines in plowing & rotarying and two machines in transplanting, pest controlling and harvesting operations. The input data are the sizes of arable lands, possible working days and number of laborers during the opimum working period, and custom rates varying depending on regions and individual farming conditions. We can find out the results such as the selected optimum combination farm machines, the overs and shorts of working days relative to the planned working period, capacities of the machines, break-even points by custom rate, fixed costs for a month, and utilization costs in a hectare.