• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.345-350
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• 2005

Acute toxicities of five pharmaceutical products were evaluated with aquatic microbes, invertebrates, and fish. The test pharmaceuticals, i.e., cimetidine, carbamazepine, diltiazem, acetaminophene, and metformin have been often detected in aquatic environment, but theire cological hazard on receptors of various trophic levels has seldom been evaluated. In the present study, we conducted acute toxicity assays with a marine bacterium, Vibrio fischeri, an invertebrate, Daphnia magna, and a fish, Japanese medake (Oryzias latipes). In general, D. magna, showed the most sensitive response to the test chemicals. Diltiazem exhibited the lowest EC50 value after 96 hr of exposure at 7.6 mg/L, followed by cimetidine >acetaminophen > metformin = carbamazepine in an order of decreasing susceptibility. With the fish, diltiazem and carbamazepine showed the 96 hr EC50 values at 14.1${\sim}$35.4 mg/L while acetaminophen, cimetidine, and metformin did not cause 50% mortality at 100 mg/L. Similar pattern was noted with the Microtox Assay, with which the median effective concentrations for acetaminophen, cimetidine, and metformin were found at the range between 301.8 and 755.4 mg/L. Carbamazepine and diltiazem exposure to the microbes resulted in EC50 values around 50 mg/L. Predicted no effect concentrations (PECs) of these pharmaceuticals derived from the EC5O values obtained from this study, and predicted environmental concentrations (PECs) obtained from available literatures were utilized to estimate ecological risks of the test compounds. No test pharmaceuticals resulted in risk quotients (PEC/PNEC) greater than 1, which suggests no serious potential ecological concerns. It should be noted however that further studies including the refinement of PEC derivation, identification and toxicity assessment of the metabolites and/or their interactions with other stressors may be warranted to better understand the environmental consequences of the residual pharmaceutical discharge to the waterway.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.4
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• pp.325-332
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• 2017

In this paper, a survey of test sequence generation methods for testing the conformance of a protocol implementation to its specification is presented. The best known methods proposed in the literature are called transition tour, distinguishing sequence, characterizing sequence, and unique input/output sequence. Also, several variants of the above methods are introduced. Applications of these methods to the finite state machine model are discussed. Then, comparative analysis of the methods is made in terms of test sequence length. Finally, conclusions are given as follows. The T-method produces the shortest test sequence, but it has the worst fault coverage. The W-method tends to produce excessively long test sequences even though its fault coverage is complete. The problem with the DS-method is that a distinguishing sequence may not exist. The UIO-method is more widely applicable, but it does not provide the same fault coverage as the DS-method.

• Journal of Nutrition and Health
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• v.45 no.4
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• pp.390-399
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• 2012

The objective of this study was to develop and evaluate the construct validity of a Nutrition Quotient (NQ) for children. In a previous report (Kang, et al., 2012), the food behavior checklist for children's NQ, consisting of 19 items, was grouped into a 5-factor structure according to the exploratory factor analysis: balance, diversity, moderation, regularity, and practice. In this study, the construct validity of the NQ was assessed using a confirmatory factor analysis. Elementary school students (n = 1,393) from six large cities completed the NQ test. Indicator tests suggested an adequate model fit (goodness of fit index = 0.9613; adjusted GFI = 0.95; standardized root mean square residual = 0.0464; chi-square test statistics of < 0.001 p-value, 82.1), and item loadings were significant for all subscales (p < 0.05). The standardized path coefficients were used as the weights of the items. The NQ and the 5 factor scores of the student were calculated by the obtained weights of the questionnaire items. Logistic regression was applied to find the significant factors in order to affect a specific nutrient status. The receiver operation characteristic curve analyses were performed in order to find diagnostic cut-off points of the five factors. The food behavior checklist for children's NQ would be a handy and suitable instrument for evaluating dietary behaviors of Korean children.

• The Journal of Korean Physical Therapy
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• v.19 no.5
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• pp.65-76
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• 2007

Purpose: It is generally accepted that smooth muscle contraction is triggered by intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) released from intracellular $Ca^{2+}$ stores such as sarcoplasmic teticulum (SR) and from the extracellular space. The increased $[Ca^{2+}]^i$ can phosphorylate the 20,000 dalton myosin light chain $(MLC_{20})$ by activating MLC kinase (MLCK), and this initiates smooth muscle contraction. In addition to the $[Ca^{2+}]_i$MACK-tension pathway, a number of intracellular signal molecules, including mitogen-activated protein kinase (MAPK), protein kinase C (PKC) and others, play important roles in the regulation of smooth muscle contraction. However, the mechanisms regulating contraction of depletion of SR $Ca^{2+}$ in mouse gastric smooth muscle strips is not still clear. Methods: To investigate the rotes of $Ca^{2+}$ influx and SR $Ca^{2+}$ release channel on gastric motility, isometric contraction and $[Ca^{2+}]_i$ were examined in mouse gastric smooth muscle strips. Results: High KCl, ryanodine, an activator of $Ca^{2+-}$induced $Ca^{2+}$ release channel, and cyclopiazonic acid (CPA), an inhibitor of SR $Ca^{2+-}$ATPase evoked a sustained increase in muscle contraction and $[Ca^{2+}]_i$. These increases induced by high KCl, ryanodine, and CPA were partially blocked by application of verapamil ($10{\mu}M$), a L-type $Ca^{2+}$ channel inhibitor. Additionally, in $Ca^{2+-}$free solution (1 mM EGTA), ryanodine and CPA had no effect contraction and $[Ca^{2+}]_i$ in fundic muscle strips. Conclusion: These results that extracellular $Ca^{2+}$ influx and depletion of SR trigger $Ca^{2+}$ influx through verapamil-sensitive $Ca^{2+}$ channel, and extracellular and SR $Ca^{2+}$ store may functionally involve in the subcellular $Ca^{2+}$ mobilization in mouse gastric muscle.

• Journal of Korean Society of Rural Planning
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• v.20 no.2
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• pp.159-171
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• 2014

This study discusses developing historical trails and ecological trails in rural area. Since the leisure time and interests in environment and health have been increasing, the number of hikers who enjoy the beautiful landscape and regional culture through the exploration of natural regions has been growing. However, these various road haven't been related to the rural village in many cases, so it is necessary to make some alternatives for revitalizing the region and improving incomes of non farm. Therefore this study suggested the applications of rural trail plan that fits for a scale of the rural village and local characteristics. This research divided forms of the rural village road into type of the natural landscape resource (Gangreung Anbandegi Village) and that of the historical culture resource (Yongin Hakil Village) according to amenity resources of objective village. The plan for village road basically made by the best of valuable resources of village unit, connected existing 'Trail' of other departments to the village and suggested a case of plan applied to the field so as to emphasize characteristics of rural area. It should be possible to induce hikers to rural area and be suggested as a measure for improvement of village image, regional vitalization and incomes of non farm.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.1
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• pp.17-24
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• 2011

It is reported that an intermittently rotating chamber system will improve the ratio of firepower to armament space in the case of mid-calibre automatic guns. However, the parallel index, which is a main component of the system, tends to be torsionally flexible due to the low lateral stiffness of cam followers on the index turret. This may cause the shaft system connecting the turret with the chamber prone to considerable residual torsional vibration so that serious misalignment problems occur during ammunition loading and firing processes. Herein, an electrorhelogical (ER) fluid actuator that can suppress such vibrations and the associated semiactive control algorithm are proposed. By mathematical modeling and computer simulations, the performance of the entire system is proved satisfactory.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.280-283
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• 2007

The first grid-connected, building-integrated transparent amorphous silicon photovoltaic installation has been operated since October 2004 in Yongin, Korea. The 2.2kWp transparent PV system was applied to the facade of entrance hall in newly constructed KOLON E&C R&D building. The PV module is a nominal 0.98m ${\times}$ 0.95m, 10% transparent, laminated, amorphous(a-Si) thin-film device rated at 44 Wp per module. To demonstrate the architectural features of thin film PV technologies for daylighting application, transparent PV modules are attached to the building envelope with the form of single glazed window and special point glazing(SPG) frames. Besides power generation, the 10% transmittance of a-Si PV module provides very smooth natural daylight to the entrance hall without any special shading devices for whole year. The installation is fully instrumented and is continuously monitored in order to allow the performance assessment of amorphous silicon PV operating at the prevailing conditions. This paper presents measured power performance data from the first 12 months of operation. For the first year, annual average system specific yield was just 486.4kWh/kWp/year which is almost half of typical amorphous silicon PV output under the best angle and orientation. It should be caused by building orientation and self-shading of adjacent mass. Besides annual power output, various statistical analysis was performed to identify the characteristics of transparent thin film PV system.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.2
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• pp.114-122
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• 2013

Objectives: This study was performed in order to investigate by questionnaire the factors affecting the occupational satisfaction of work-environment measurement workers, as well as to suggest fundamental materials for systematic, administrative and economic improvements which are necessary to create a vision for the future. Material and Methods: A structured questionnaire was used at a total of 152 institutions and 1,254 work-environment measurement workers throughout the country from February to September 2012. Responses came from 97 institutions (64%) and 941 work-environment measurement workers (75.1%). The factors affecting the job satisfaction of work-environment measurement workers were statistically evaluated through $x^2$-test and ordinal logistic regression analysis. Results: Major factors affecting the job satisfaction of workers in relation to work-environment measurement were working, financial, and psychological conditions (p<0.05). Conclusions: Considering the results of this study, the improvement of labor conditions should be undertaken because workers engaged in work-environment measurement are fundamental to occupational health.

• School Mathematics
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• v.15 no.4
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• pp.847-866
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• 2013

The purpose of this study was to analyze students' various solution methods revealed in the lessons of finding out the area of plane figures, and to explore instructional implications on how to draw meaningful formalization out of such multiple methods. The teacher in this study tended to select a few solution methods that were easy for students to understand and to induce formalization. An analysis of students' solution methods and the process of formalization showed that students need to understand what parts of the length of the given plane figure they should know, and to identify the base, height, and diagonal line of the figure. The analysis also showed that it was effective to choose the solution methods that were used by many students and that could be easily transformed into a concise formula. Based on these results, this paper provides instructional suggestions for a teacher to orchestrate classroom discussion toward formalization based on students' multiple solution methods.

• Journal of Korean Physical Therapy Science
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• v.5 no.2
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• pp.595-602
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• 1998

The purpose of this study was to investigate the effect of sequential intermittent pneumatic compression in patients with lymphedema who were hospitalized for three days at Samsung Medical Center. Thirty-three subjects with lymphedema was selected by physician referral. A selection of the patients was made according to the following criteria : 1) no known metastases, 2) no infection after the a difference of at least 10% in the volumes of edematous limb. All patients were treated with the Lympha-Press(Model 103-A). Circumferential limb mesurements was done before and after a 3-day treatment period. As a result of sequential intermittent pneumatic compression therapy. All extremity showed a decrease in circumferential measurements with the maximal reduction occurring at the wrist(55.75 %) for the upper extremities and at the lower 1/3 of calf (40.61%) for the lower extremities. Upper extremity arm was reduced by 42.1% and lower extremity leg by 33.61%. In contrast with this, the proximal levels of arm patients and leg showed comparatively poor reduction than distal levels. Almost 44.44% of arm patients and 5.26% of leg patients experienced significant reduction(> 50%) after compression therapy. These data clearly indicates that Sequential Intermittent Pneumatic Compression Therapy was effective treatment for reducing of extremity volume in patients with lymphedema. but this was variable degree and dependent on the amount of pre-existing lymphedema. Other factors such as duration of edema, etiology, previous history of radiology, age did not appear to influence the extend of improvement. Further sutdies will be necessary to determine long term benefit of this therapy.