• Journal of Plant Biology
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• 제36권4호
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• pp.337-343
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• 1993

Tracheid structure of aerial system in five species of Ophioglossaceae and one species of Osmundaceae was examined with light and scanning electron microscopy. The species were Botrichium multifidum var. robustrum, B. ternatum, strictum, B. virginianum, Ophioglossum vulgatum, and Osmunda japonica. Three types of tracheids could be recognized by the pattern of secondary wall thickening; helical, irregular reticulate and circular bordered pitted tracheids. Among them, the appearance of circular bordered pitted tracheids supported that ophioglossaceous plants might have phylogenetic relationship with progymnosperm-seed plant line. Circular and elliptical bordered pits in shape were observed in five ophioglossaceous species; the former was subdivided into large and small types in size. In conclusion, three types of bordered pits were found: (1) large circular type- O. vulgatum, (2) small circular type- B. multifidum var. robustrum, B. ternatum and (3) elliptical type-B. strictum, B. virginianum. B. strictum and B. virginianum belong to subgenus Osmundopteris had the elliptical bordered pits. Therefore, this group might be interpreted as the most primitive in this family; however, such suggestion did subgenus Osmundopteris was classified into the most advanced group.

• 아동학회지
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• 제22권3호
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• pp.241-256
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• 2001

This study investigated types of language during dyadic collaboration on 2 spatial perspective problems. Subjects were 3 groups of children consisting of 14 dyads each of boys and of girls paired by age and sex, totaling 168 6-, 8-, and 10-year-old children. The entire procedure was videotaped. Data were processed by t-test and one-way ANOVA. Older children used less ego-centric and more socialized speech than younger children. No age differences were found for degree of exploration without collaboration, quarreling, or nonabstract collaborative explanation. The 10-year-olds used more abstract collaborative explanation, primitive argument, and genuine argument than the 6-year-olds.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
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• pp.170-175
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• 1998

Transporting a large table using multiple robotic agents requires at least two group behaviors of homing and herding which are to bo coordinated in a proper sequence. Existing GP methods for multi-agent learning are not practical enough to find an optimal solution in this domain. To evolve this kind of complex cooperative behavior we use a novel method called fitness switching. This method maintains a pool of basis fitness functions each of which corresponds to a primitive group behavior. The basis functions are then progressively combined into more complex fitness functions to co-evolve more complex behavior. The performance of the presented method is compared with that of two conventional methods. Experimental results show that coevolutionary fitness switching provides an effective mechanism for evolving complex emergent behavior which may not be solved by simple genetic programming.

• BMB Reports
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• 제31권3호
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• pp.264-268
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• 1998

Dopamine (DA) acts on swimming motor neurons (SMNs) of Polyorchis penicillatus as an inhibitory neurotransmitter by hyperpolarizing their membrane potentials, which results from the activation of voltagesensitive potassium channels mediated through a $D_2-type$ receptor. In addition, DA, and not the hyperpolarized membrane potential, directly decreased the input resistance of SMNs by ca. 50% from 1.42 to 0.68 $G{\Omega}$. It strongly indicates that DA can shunt other excitatory synaptic signals onto SMNs where DA usually elicited much greater responses in their neurites than soma. All these evidences suggest that DA may operate in this primitive nervous system in dual modes as an inhibitory neurotransmitter and neuromodulator as well.

• 한국가구학회지
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• 제26권1호
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• pp.51-60
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• 2015

Interior designer Sugimoto Takashi uses salvaged material and natural thing for aesthetical purpose. These material performs not just as fun stuff but as design tool in order to set up cultural meaning which modern society always lacks for. The method of communicating the meaning is the multi-layered trace on them. There are three types of trace. They are harsh texture of surface, untrimmed outline, and gathering & arrangement. Through these formation methods of trace, Sugimoto can suggest various curtural meanings such as vanishing value of old-fashioned lifestyle, primitive energy of nature, and sincere touch of somebody. As a result, the trace in Sugimoto's design is an endeavor to exist tradition(the long ago) and nature(the far away) in here-and-now interior space.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 추계학술대회 논문집
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• pp.200-205
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• 1993

The automatic forming sequence design system can determine desirable operation sequences even if they have little experience in the design of cold forging process. This system is proposed,which generates forming sequence plans for the multistage cold forging of zxisymmetrical solid products. Since the process of metal forming can be considered as a transformation of geometry, treatment of the geometry of the product is a key in planning processes. Forming sequence for the part can be determined by means of primitive geometries such as cylinder,cone, convex, and concave. By utilizing this geometrical characteristics(diameter,height, and radius),the product geometry is expressed by a list of the pnmitive geometries. Accordingly, the forming sequence design is formulated as the search problem which starts with a billet geometry and finishes with a given product one. Using the developed system, the sequence drawing with all dimensions, which includes the proper sequence of operations for the part, is generated under the environment of AutoCAD. The preliminary choice of some feasible forming sequences can verify by using the finite element simulation.

• Journal of Chest Surgery
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• 제27권9호
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• pp.812-814
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• 1994

The esophageal cyst result from a wrong cleavage of the primitive gut in the 4 weeks embryo. In embryo and after seperation of the tracheal diverticulum, the esophagus is lined with ciliated cells which are able cover a "cystic duplication". It is often difficult to distinguish between the bronchogenic and the esophageal cyst. Pathological findings showed the presence of a ciliated epithelium without cartilage which was diagnosed as an esophageal cyst. The patient was 21 year old man for evaluation of the cyst in the posterior mediastinum. The cyst was located the intramural esophagus. Microscopically, the cyst was lined with ciliated columnar epithelium and there was no evidence of cartilage. The cyst was confirmed as the intramural esophageal cyst.geal cyst.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.521-526
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• 1991

High speed power switching technology is essential in developing high-frequency induction heating power supply. Since technological level of domestic industry is primitive, most of key technology is imported from the advanced foreign countries, and academic research will short of demand. Because of this background, this project requires national attention. Therefore, based on existing high-frequency technology, high-power high- frequency power supply for induction heating will be developed and various key technology in power switching technology, which will be used widely in industry, will be estabilished.

• 한국컴퓨터산업학회논문지
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• 제5권9호
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• pp.1031-1042
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• 2004

대체에너지원 데이터는 측정값이 시시각각으로 변경되는 특성을 갖기 때문에 시간의 변화에 따라 발생되는 원시 데이터의 양이 상당히 방대하다. 따라서 대체에너지원 데이터의 이력 정보를 체계적으로 저장 및 관리할 수 있는 이력 데이터베이스의 구축과 대체에너지원 예측 시스템에 대한 연구가 필요하다. 이 논문에서는 대체에너지원 데이터의 과거 측정값에 대한 추정 기능의 지원을 통해 시시각각으로 변화하는 데이터를 체계적으로 관리하기 위한 대체에너지원 추정 기법을 제안하였다.

• Journal of Chest Surgery
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• 제18권2호
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• pp.327-333
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• 1985

Pulmonary arteriovenous fistula is a congenital malformation of the pulmonary vasculature in which there is a persistence of one or more sizable communications that bypass the pulmonary capillary bed that thus directs unoxygenated pulmonary arterial blood directly into the pulmonary venous system. The developmental cause of pulmonary arteriovenous fistula is unknown, but it is postulated that the abnormal channels represent persistent vessels of the primitive splanchnic capillary bed that do not resorb during growth and maturation. We have experienced a case of pulmonary arteriovenous fistula. The 45 years old woman admitted to Kosin Medical College Hospital via emergency room because of massive hemoptysis, and was diagnosed pulmonary arteriovenous fistula by twice postoperative histopathologic examination. The postoperative course was uneventful and she was discharged on the 16th, second postoperative day in a healthy condition.