• Steel and Composite Structures
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• 제46권4호
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• pp.553-563
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• 2023

In the current research, the nonlinear free vibrations of curved pipes made of functionally graded (FG) carbon nanotube reinforced composite (CNTRC) materials are investigated. It is assumed that the FG-CNTRC curved pipe is supported on a three-parameter nonlinear elastic foundation and is subjected to a uniform temperature rise. Properties of the curved nanocomposite pipe are distributed across the radius of the pipe and are given by means of a refined rule of mixtures approach. It is also assumed that all thermomechanical properties of the nanocomposite pipe are temperature-dependent. The governing equations of the curved pipe are obtained using a higher order shear deformation theory, where the traction free boundary conditions are satisfied on the top and bottom surfaces of the pipe. The von Kármán type of geometrical non-linearity is included into the formulation to consider the large deflection in the curved nanocomposite pipe. For the case of nanocomposite curved pipes which are simply supported in flexure and axially immovable, the motion equations are solved using the two-step perturbation technique. The closed-form expressions are provided to obtain the small- and large-amplitude frequencies of FG-CNTRC curved pipes rested on a nonlinear elastic foundation in thermal environment. Numerical results are given to explore the effects of CNT distribution pattern, the CNT volume fraction, thermal environment, nonlinear foundation stiffness, and geometrical parameters on the fundamental linear and nonlinear frequencies of the curved nanocomposite pipe.

• 환경생물
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• 제39권4호
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• pp.507-514
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• 2021

A new free-living marine nematode species of the genus Pseudosteineria Wieser, 1956 affiliated with the family Xyalidae is described based on specimens collected from the sediment of a subtidal benthic environmental habitat in the East Sea, Korea. Pseudosteineria varisetis sp. nov differed from its congeners by the combination of the following characteristics: a relatively long body (1,628-1,691 ㎛ long in males), a circular amphideal fovea situated behind the subcephalic setae, the presence of lateral cuticular alae starting from behind the nerve ring, the presence of eight groups of long subcephalic setae, the presence of irregularly distributed variable lengths of somatic setae on the body, solid spicules (43.2-43.9 ㎛ long) with a cephalated proximal end, a long tubular shaped gubernaculum with dorsal swelling, and a conico-cylindrical tail with two to four terminal setae. In this report, we provide a taxonomic description and illustrations of a new species of the genus Pseudosteineria by differential interference contrast microscopy.

• 환경생물
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• 제40권4호
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• pp.477-496
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• 2022

During a survey of free-living marine nematodes of Korea, two new marine desmoscolecid nematodes belonging to subgenus Quadricoma Filipjev, 1922 were discovered. Tricoma (Q.) jejuensis sp. nov. and T.(Q.) unipapillata sp. nov. are described based on specimens obtained from washings of coarse sediments from eastern and southern coasts of Korea. Tricoma (Q.) jejuensis sp. nov. is characterized by having 33 quadricomoid body rings and inversion at main ring 23, pentagonal head with truncated anterior end, a pair of ocelli situated at main ring 6, somatic setae comprising of 8 pairs of subdorsal setae and 12 pairs of subventral setae, and relatively short spicules (42-46 ㎛ long). Tricoma (Q.) unipapillata sp. nov. is characterized by 44 quadricomoid body rings and inversion at main ring 32, somatic setae comprising of 7 pairs of subdorsal setae and 10 pairs of subventral setae, globular head truncated anterior end, relatively short and stumpy cephalic setae with cuticular flange, one single naked ventral median genital papillae situated on main ring 20, and spicules with a proximally marked capitulum. Detailed morphological descriptions and illustrations of these two new species are provided in this study.

• 환경생물
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• 제41권4호
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• pp.570-607
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• 2023

The subgenus Tricoma Cobb, 1894 comprises free-living marine nematodes encompassing a total of 83 validated taxa. Within this diversity, twenty-one taxa thrive in the deep sea, while twenty-three are found in coral reefs, flat areas, or green algae. Additionally, eleven taxa inhabit the sublittoral zone at depths exceeding 10 meters, and the remaining taxa are situated on beaches, coasts, or in habitats lacking detailed information. In the course of a survey focused on the East Sea free-living marine nematodes, we identified four new and two previously unrecorded species belonging to the subgenus Tricoma. Specifically, two new species, Tricoma (Tricoma) breviseta sp. nov. and T. (T.) donghaensis sp. nov., were discovered in mud-sandy sediment in deepsea environments below 2000 meters within the Ulleung Basin and Hupo Bank. Two previously unrecorded species [T. (T.) paralucida Decraemer, 1987 and T. (T.) similis Cobb, 1912] and the two newly found species [T. (T.) longicauda sp. nov. and T. (T.) ulleungensis sp. nov.] were obtained from subtidal coarse sand at a depth of 20 meters during a survey of the waters surrounding Ulleungdo Island. The distribution and information on validated taxa within the subgenus Tricoma were systematically collected, reviewed, and cataloged. Detailed morphological features and illustrations of Tricoma species from Korea were provided through the use of differential interference contrast microscopy.

• 교육시설
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• 제15권1호
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• pp.53-61
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• 2008

Under recent educational and social backgrounds, alternative education schools are increasing continuously, to compare Japanese example that experience of similar circumstance given before with the investigation of general present condition, specialized education contents, facilities and utilization of 5 schools of Tokyo area, I could know following contents ; First, free schools of Tokyo area were operated by individual education type that consider each student's special quality maximum comparing with Korea's alternative schools which seek community education type. Second, there were not many schools which prescribe school personal allowance per division or class comparing with our cases that operate divides step by equal class with general school and prescribes personal allowance by class, and whole students are generally about $20{\sim}30$. Third, comparing with our cases that are located in mountain and rural area according to profitable locational conditions for environment and experience studying, it was general which islocatedin downtown for the purpose of free attending school of non attending school students. Fourth, usually, comparing with our that unused schools in mountain and rural area are general for alternative school and there were a lot of cases that uses small building of downtown such as lease office, unused warehouse and factory for free school of Tokyo area.

• 펄프종이기술
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• 제44권2호
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• pp.42-48
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• 2012

In the 21st century, the printing industry as well as the IT industry has made rapid development. However, despite these technological advancement in the printing industry, it is still harmful for the environment, the state regulation is insufficient. Therefore, we studied the printability for the existing heat-set web inks and the newly created phenol-free eco-inks. This ink was made by reacting rosin and unsaturated dibasic acid and ester reactant, ester reactant was used instead of phenol. Printability test were used in the IGT printability tester. Experimental conditions, the temperature $22.7^{\circ}C$, humidity 57% under conditions of 0.6cc of ink supply, the print speed 1m/sec, pressures were set at 250N. As results of this study, we were able to get the following conclusions. The properties of phenol-free ink is the same as the existing inks. So we are thought to improve some characteristics such as dispersion, able to replace the existing ink.

• Human Ecology Research
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• 제56권4호
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• pp.331-345
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• 2018

This study explored the sandplay therapy case of a woman with a negative mother complex who wants to be free from family life. The goal of the therapy was to make her free from family life by expressing repressed emotions for getting out of a negative mother complex under a free and protected space in sandplay therapy. Twenty-three therapy sessions were held. The client exhibited a singing woman in a gorgeous dress and things she wanted to do in the initial phase of therapy (1-4, forgotten myself). In the intermediate phase of therapy (5-15, differentiation and integration), she displayed the scenes of differentiation and integration by emotionally getting rid of a begging boy and making mandalas. In the final phase of therapy (16-23, recovered myself), she showed scenes of rebirth, upgrading and singing songs again in front of family members and many people. Through sandplay therapy in the free and protected space, this study showed the effectiveness of sandplay therapy since the client achieved individuation by showing rebirth, having a new personality.

• 한국항공우주학회지
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• 제44권6호
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• pp.463-467
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• 2016

본 연구에서는 충격파 풍동을 이용하여 초음속 환경에서 사람 모델이 받는 압력과 가속도를 측정하였다. 전자석과 철가루가 내포되어 있는 3차원 사람 모델을 이용하여 모델 지지대로 인한 유동 흐름의 방해가 없는 자유 낙하 기법을 사용하였다. 마하 4 유동조건에 서 자유 낙하 실험을 수행하였으며, 실험을 통해 획득한 유동 가시화 이미지로 시간에 따른 사람 모델의 위치 변화를 파악하고 이를 통해 모델에 가해진 힘을 측정하였다.

• KIEAE Journal
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• 제10권1호
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• pp.91-96
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• 2010

Incheon Free Economic Zone's Songdo Area is a newly constructed city built on land reclaimed from the seaside and the surrounding area. Yeongjong Area is made after Land reclamation between Yeongjong Island and Yongyou Island began in November 1992. The first phase linking these islands to create the Incheon International Airport (phase 1) and the Airport Town Square community was finished in March 2001. However, if we take a look at the overall status of the project as it is carried on at present, it is hard to deny that the project is trapped inside the same legal restrictions as are all other existing cities, which permits Songdo Area and Yeongjong Area to meet only very minimum standards. This study intends to analyze and assess the Incheon Free Economic Zone's Songdo Area and Yeongjong Area of environmentally friendly construction and to rate its current development status, exposing any problems and offering alternative solutions. In this paper, the current state of constructions in Songdo Area and Yeongjong Area were reviewed. Then a quantitative analysis and assessment for the Songdo Area and Yeongjong Area constructions of apartments, complex buildings, office buildings, school facilities, store and hotel facilities were conducted by using green building certification criteria. Finally the synthetic results of environmental performance evaluation for Incheon Free Economic Zone's Songdo Area and Yeongjong Area constructions and follow-up suggestions were described.

• 디지털산업정보학회논문지
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• 제14권4호
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• pp.229-239
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• 2018

In this paper, we propose a strategy of charging by analyzing the difference of path coefficient according to whether consumers are free or not, rather than presenting strategies for charging. Mobile devices have become so popular that they are called necessities. Companies have to adapt to the mobile environment and respond to the situation, and have to expand market opportunities strategically. In this study, we extend the technology acceptance model to analyze the incentives of consumers' behavior by analyzing the difference in the effect consumers perceive as a moderating variable, whether paid or free. Efforts to maximize company's inherent profit continue, and in particular, charging is a strategy that all companies should pursue in the mobile environments. It is necessary to grasp the degree of the consumer's response to free and charge. The model of satisfaction with the continuous use and the word-of-mouth intention, which is the behavior intention, is presented by adding parameters of satisfaction to the technology acceptance model. In addition, we try to derive implications by analyzing the influence of moderating effects of whether free or not.