• Title/Summary/Keyword: 원추형

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동해안 참가자미, Limanda herzensteini의 생식주기

  • 장윤정;이정용;장영진
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2003.10a
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    • pp.53-53
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    • 2003
  • 참가자미, Limanda herzensteini는 가자미목 (Pleuronectiformes), 가자미과 (Pleuronectidae)에 속하며, 우리나라의 동해, 일본의 세토내해 이북, 중국 및 사할린 근해에 분포하는 어종이다. 본 종은 연안정착성 어종으로 동해안에서 낚시 및 저인망 어업에 의해 어획되는 산업적 가치가 큰 고급어종이며, 저수온에 강하여 한류성 해역에서의 양식 가능성이 매우 높다고 할 수 있다. 또한 최근에는 참가자미의 자원량 감소가 두드러지고 있으므로 자원증강이 절실히 요구된다. 이 연구에서는 주 어획지역인 강원도 주문진 인근해역에서 1998년 9월부터 1999년 10월까지 자연산 참가자미의 연간 생식소중량지수의 변화를 조사 하였으며, 조직학적 조사에 의한 생식소 발달과정과 생식주기를 밝혔다. 정소는 정소엽 형태이며, 각각의 정소엽은 여러개의 소낭구조를 가진다. 각 소낭내의 생식세포들은 같은 단계의 발달상태를 보인다. 난소는 원추형의 낭상으로 체강벽에서 연결되는 난소간막에 의해 부착되어 있으며, 내부는 결체성 조직인 다수의 난소박판으로 구성되며, 이곳에서 난원세포가 유래한다. 수컷의 GSI는 1월에 가장 높았으며, 암컷의 GSI는 3월에 가장 높은 값을 보였다. 생식주기는 성장기(6~9월), 성숙기(10~12월), 완숙 및 산란기(1~3월) 그리고 회복 및 휴지기(4~5월)로 나눌 수 있었다. 난모세포의 발달양식은 난군동기발달형에 속하였다.

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Experimental Study of Thermo-Flow Field in a Model Gas Turbine Combustor with Various Swirl Conditions (스월변화에 따른 모형 가스터빈 연소기의 열유동장의 실험적 연구)

  • Ryu, Song-Youl;Koo, Ja-Ye
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.30 no.4
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    • pp.70-76
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    • 2002
  • Characteristics of kerosine spray combustion were investigated at various swirl condition. PDPA(Phase Doppler Particle Analysis) was used to measure the droplet sizes and velocities. R-type(Platinum vs. Platinum-13%rhodium) thermocouple was used to measure the temperature of combustion flow field inside model combustor. A visualization of spray and flame was performed with still camera. As swirl number increases due to increase of swirl vane angle, the spray and the flame were developed to radial direction rapidly. When swirl number is small, the configuration of flame is cone type, but swirl number is large, the configuration of flame is cylindrical type due to enhanced mixing by the transport of swirl momentum.

A Study on Development of Ferrite Wave Absorber with Cutting Corn-Shaped Type (원추절단형 폐라이트 전파흡수체의 최적설계 및 제작에 관한 연구)

  • 김동일;박종구;정세모;이영구
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2000.10a
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    • pp.153-156
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    • 2000
  • The remarkable progress of electronics and radio communications technology has made our life abundant. On the other hand, the countermeasure of EMC becomes more important socially according to the increased use of electromagnetic waves. It had been required that the absorbing ability of an electromagnetic wave absorber is more than 20 dB, the bandwidth of which is required through 30 MHz to 1,000 MHz for satisfying the international standard about an anechoic chamber for EMI/EMS measurement. From November of 1998, however, the CISPR11 has accepted the extended frequency band from 30 MHz to 18 GHz in the bandwidth of EMI measurement. In this paper, we proposed the cutting com-shaped type satisfying the above requirments and carried out broadband design using the equivalent material constants method. Moreover, we have fabricated it and compared its characteristics with simulated one.

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Reproductive Cycle of the Brown sole, Limanda herzensteini in Eastern Waters of Korea (동해안 참가자미, Limanda herzensteini의 생식주기)

  • 장윤정;이정용;장영진
    • Journal of Aquaculture
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    • v.17 no.2
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    • pp.128-132
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    • 2004
  • Reproductive cycle of the brown sole, Limanda herzensteini was investigated by means of histological methods. The testis showed the presence of seminiferous tubule. The tubule consisted of many testicular cysts, each of which contained numerous germ cells - all at the same developmental stage. The ovary consisted of several ovarian lamellae and the oogonia originated from the inner surface of the ovarian lamella. Oocyte development was group-synchronous. Gonadosomatic index (GSI) of the male and female was the highest in January and March, respectively. Reproductive cycle could be classified into the growing (June-September), maturation (October-December), ripe and spent (January-March), and recovery and resting (April-May).

A Study on Development of Ferrite Wave Absorber with Cutting Corn-Shaped Type (원추절단형 페라이트 전파흡수체의 최적설계 및 제작에 관한 연구)

  • 김동일;박종구;정세모;이영구
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.4 no.4
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    • pp.721-726
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    • 2000
  • The remarkable progress of electronics and radio communications technology has made our life abundant. On the other hand, the countermeasure of EMC becomes more important socially according to the increased use of electromagnetic waves. It had been required that the absorbing ability of an electromagnetic wave absorber is mote than 20 dB, the bandwidth of which is required through 30 MHz to 1,000 MHB for satisfying the international standard about an anechoic chamber lot EMl/EMS measurement. From November of 1998, however, the CISPR11 has accepted the extended frequency band from 30 MHz to 18 GHz in the bandwidth of EMI measurement. In this paper, we proposed the cutting corn-shaped type satisfying the above requirements and carried out broadband design using the equivalent material constants method. Moreover, we have fabricated it and compared its characteristics with simulated one.

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Taesil Seokham Styles of the Joseon Royal Family (조선왕실(朝鮮王室) 태실석함(胎室石函)의 현황(現況)과 양식변천(樣式變遷))

  • Shim, Hyun Yong
    • Korean Journal of Heritage: History & Science
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    • v.43 no.3
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    • pp.208-241
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    • 2010
  • This study was conducted to examine the chronology of Taesil Seokham(Taesil Stone Boxes) stored in Taesil of the Joseon Palace and classify the styles to discuss how these boxes have developed. By doing so, this study defined the archaeological styles of taesil seokhams in the chronological order. Although taesil seokhams are placed when taesil are first created, they do not have any texts engraved on them and it is difficult to gain information only from examining taesil seokham. However, Taejiseok(memorial stones buried in Taesil) and Agibi(gravestones buried in Taesil) were created along with taesil. These resources were examined and compared with literature records to find when each taesil seokhams was created. The critical elements to consider for the chronological arrangement were both the cover and container of the boxes and the transition of their style could be classified into four major stages. In detail, the Joseon Dynasty's taesil seokhams initially inherited the style of the Goryeo Dynasty to be formed into rectangular boxes. Through the transition of the mid and late 15th Century, the semi-circular cover with cylindrical container became the popular style in the late 15th Century. In the late 16th Century, the style of the previous period was further developed to add some decorative elements, such as projecting ornaments, but the ornaments were added for functional purposes rather than artistic purposes. However, the style went back to the semi-circular cover with cylindrical container in the early 17th Century. From the mid 17th Century, various styles appeared with ornaments only on the cover, cone-shaped cover with no ornament, or mortar-like container. However, a new style of cone-shaped cover with ornament emerged between the early and mid 18th Century and continued to stay until the mid 18th Century. In the mid 18th Century, the cover remained unchanged, but the container became a keyhole-shaped space with one side forming a "ㄷ" shape. However, in the late 18th Century, the most typical style of the semi-circular cover with cylindrical container reappeared to show that this is the most universal style. Last, in the mid 19th Century, the cover changed from semi-circular to rectangular with flat top. After this, the taesil seokhams began to disappear. In terms of style, it can be classified into four stages. In the early Joseon Dynasty, the taesil seokhams were underdeveloped and inherited the style of the Goryeo Dynasty (Stage I; 1401~mid-15C), but Joseon's unique style began to develop from the late 15th Century (Stage II; 1477~1641). After that, partial ornaments were added for adornment (Stage III; 1660~1754), but the typical style reappeared in the late 18th Century to finally degrade in the late Joseon Dynasty of the mid 19th Century (Stage IV; 1790~1874). This arrangement of style and chronology would greatly help archaeologists anticipate the time and owner of taesil seokhams even if only taesil seokhams are discovered without any records. * Tae(胎) : Placenta and umbilical cord * Taesil(胎室) : A facility(chamber) of burying Tae(胎) in rite when royal descendants are born.

A Study on The Perceived Breast Shapes of Adult Women according to the Age (성인여성의 연령에 따른 유방형태 인식에 관한 연구)

  • 김영숙
    • Journal of the Korea Fashion and Costume Design Association
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    • v.5 no.1
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    • pp.59-71
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    • 2003
  • The purpose of this study is to provide for the basic data useful to the development of a quality brassiere featuring a good wearing feeling and an effect of reinstating and correcting breast shape. For this purpose, 220 adult women aged between 20 and 59 were sampled to survey their perceived and actual breast shapes. The results of this study can be summarized as follows; 1. Most adult women correctly perceive the changes of their breast shapes as they become older. However, the younger women tend to evaluate their breast as larger than their actual sizes, being more dissatisfied with their breast shapes than older women, while wanting their constitution to be more high and slim. In short, there is a little difference between their perceived and actual breast shapes. 2. The breast shape perceived most by the adult women is "droopy type I"(37.7%), followed by "conical type"(21.8%), "flat type"(16.8%), "semi-circular"(10.8%), "droopy type II"(8.6%) and "extruded type"(5.0%) in their order. The younger women tend to perceive their breasts as "flat", "conical" or "semi-circular", while the older women tend to perceive their breasts as "droopy". 3. According to the increase of age, the items of height were decreased and items of width, depth, circumference and length were increased, being obser and breast point were drooped. so volume and bottom area of breast of 40ㆍ50's women's age group were larger than 20?30's women's age group and breast point width of 40ㆍ50's women was being wider by increase of interior dimensions of breast.

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Low-velocity Impact Damage of a Thick Pressure vessel (복합재료 만든 두꺼운 압력용기의 저속충격에 관한 연구)

  • 김형원
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2000.11a
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    • pp.92-97
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    • 2000
  • Low-velocity impact damage of a thick pressure vessel by composite materials was studied using the modified Herzian contact radius theory. Impactors of various masses and various tup shapes were dropped freely in the range of 20m to 200mm height. With acceleration gage and strain gage installed on the impactor, impact force and acceleration and Contact radius were measured. After a test, the samples were radiographed to scan the state of damage. Compared with hemispherical tup of 12.7mm diameter, the contact radius of hemispherical tup of 25.4mm diameter was bigger. And the experimental data and the theoretical data was different due to the mechanical properties difference. The acceleration value was changed linearly according to the height.

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DENS INVAGINATUS AND TALON CUSP CO-OCCURING: REPORT OF THREE CASES (치내치를 동반한 탈론 교두: 증례보고)

  • Im, Sung-Ok;Lee, Sang-Ho;Lee, Nan-Young
    • Journal of the korean academy of Pediatric Dentistry
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    • v.37 no.4
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    • pp.488-496
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    • 2010
  • Dens evaginatus is a tooth with cylindrical enamel projection which forms a nodule on occlusal surface. It could be explained as outward overgrowth of inner enamel epithelium or localized hyperplasia of pulpal mesenchymal tissue during tooth development. A problem is that it is likely to be worn out or fractured by mastication ensuing pulpal inflammation. It is occasionally found on the lingual surface of upper anterior teeth as well, called talon cusp. Dens invaginatus is a tooth with deep lingual pit made by invagination of lingual enamel epithelium during tooth development while it is considered normal in terms of size and shape. Radiographically, a part of cervical enamel shows inward growth forming cavity and it is reasonable to say that the base is possibly open to pulpal cavity since they are very close. Talon cusp and dens invaginatus are relatively common abnormality of shape. However it becomes the opposite if the two exist in the same tooth. Once the talon cusp is broken by occlusal force or fissure between cusps is decayed, the complicated structure of canals makes the pulpal treatment difficult. Preventive treatments such as occlusal equilibrium and sealant, and regular oral examination should be preceded and thorough understanding of canal shape, using radiography, is required when pulpal treatment is necessary. This report is about a 9- year-old boy(lower left central incisor), a 8-year-old girl(upper right central incisor), and a 7-year-old boy(upper right central incisor), who have dens invaginatus and talon cusp in the same teeth. The first and the second patients are under pulpal treatments, and the last one is being observed showing no pathologic impressions.

Behavior of Floating Top-Base Foundation on Soft Soils by Laboratory Model Tests (실내모형실험을 통한 연약지반에서 부양형 팽이기초의 거동)

  • Chung, Jin-Hyuck;Chung, Hye-Kwun;Lee, Song
    • Journal of the Korean Geotechnical Society
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    • v.27 no.2
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    • pp.5-15
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    • 2011
  • This research performed the laboratory model tests for Top-Base Foundation developed in Japan and Floating Top-Base Foundation developed in Korea on the typical clayey soft soils, namely, clay, clayey silt and clayey sand. The performances of the two types of top-base foundation were compared with each other and evaluated by measuring load-settlement, heaving of foundation side, ground stress distribution in this model tests. The change of settlement caused by the increase of top base width was also analyzed. As a result of the model tests, Floating Top-Base Foundation showed better performance in bearing capacity improvement, settlement decrease, stress dispersion effect and lateral confinement force. And settlement caused by the increase of top base width converged to a regular value from $5{\times}5$ layout of the width.