• 제목/요약/키워드: Third-order

검색결과 6,134건 처리시간 0.035초

렌즈모듈을 이용한 광학계 설계 I: 줌렌즈의 First Order 최적설계 (Optical system design using lens modules I:optimum first order design in zoom lens)

  • 박성찬;김영식
    • 한국광학회지
    • /
    • 제8권2호
    • /
    • pp.81-87
    • /
    • 1997
  • 본 논문은 4군구성의 비디오 카메라용 줌광학계에 대해 렌즈모듈의 개념을 이용하여 1차량 및 3차 수차를 고려한 최적의 초기설계와 이로부터 설계 줌광학계를 설계하는 방법을 제안하였다. 최적화 과정을 통해 각각의 렌즈모듈에 적절히 1차량과 3차 수차량을 설정함으로써 줌비 10배(f'=6.1693~58.4065)를 갖고, 최적설계에 필요한 구속조건을 만족시키는 초기설계 줌광학계를 얻었다. 적절히 선정된 각각의 렌즈군의 촛점거리가 렌즈모듈의 촛점거리와 같도록 scaling 한 후, 군사이의 공기간격을 조정하므로써 줌궤적을 일치시켰다. 이러한 과정을 통해 독립적으로 설계된 군들을 결합시켜 얻은 줌광학계는 렌즈모듈로 구성된 원래의 초기설계된 줌광학계와 동일한 1차특성을 갖는다. 결과적으로 잔여수차 보정을 통해 후군촛점조절방식을 이용하는 비디오 카메라 줌렌즈로서 유용한 줌광학계를 얻을 수 있었다.

  • PDF

냉장물류센터 내 운반장비 운영계획에 관한 연구 (Transporter Operation Planning for Refrigerated Warehouse Using Simulation Method)

  • 황흥석;김호균;조규성
    • 산업공학
    • /
    • 제15권4호
    • /
    • pp.382-390
    • /
    • 2002
  • This paper deals with planning of order-picking warehouse considering the batch order picking for transportation equipments to pick consumers' orders at a time among order-picking methods and a systematic approach method in order to analyze the order-picking warehouse which can perform optimal operation. To estimate an operating time of transportation equipments to carry out order-picking, this paper suggests three operations : first, to design the refrigerated warehouse using warehouse design parameters, second, to calculate the travel time of transporters considering four types of times with the probabilistic picking frequency, and third, to analyze an order-picking warehouse to construct a simulation model with the AutoMod as a simulation tool. We apply this model to a refrigerated warehouse company in Busan.

영구대구치(永久大臼齒)의 교합면상(咬合面上)에 나타난 발육구(發育溝)의 변이(變異)에 관(關)한 연구(硏究) (A study on the variation of the developmental grooves on the occlusal surface of the permanent molars in Korea)

  • 이영은
    • 대한치과기공학회지
    • /
    • 제11권1호
    • /
    • pp.65-70
    • /
    • 1989
  • The development of the lobe pattern in the human dentition plays a part in the form and function of each individual teeth. In order to determin the morphological categories used to describe the occlusal surfaces of the maxillary and mandibular molars, the variation of the developmental grooves which separate each lobe in the molars was examined and analysed. The obtained conclusions were as follow. 1. Most of the maxillary first molars with more distinct and more developmental grooves than the other molars but in most cases of the third molar, a heart-shaped outline due to poorly developed or abscent distolingual cusp was most frequent and in this case the third molar had the 3 cusps separated by the central developmental groove and the buccal developmental groove. 2. In most cases, the mandibular first molar had the 5-cusp type that the groove patter resembles a Y, the second molar the 4-cusp type arranged in such a way that the buccal and lingual developmental grooves meet the central developmental groove at right angle on the occlusal surface and many instances of the mandibular third molars had the 5-cusp thpe with a+groove pattern which separatess the mesiolingual cusp from the distobuccal cusp and the 4-cusp type with a+groove pattern. 3. The maxillary and mandibular third molar were most variable in the developmental groove.

  • PDF

Assessment of the proximity between the mandibular third molar and inferior alveolar canal using preoperative 3D-CT to prevent inferior alveolar nerve damage

  • Lee, Byeongmin;Park, Youngju;Ahn, Janghoon;Chun, Jihyun;Park, Suhyun;Kim, Minjin;Jo, Youngserk;Ahn, Somi;Kim, Beulha;Choi, Sungbae
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • 제37권
    • /
    • pp.30.1-30.7
    • /
    • 2015
  • Background: The inferior alveolar nerve (IAN) may be injured during extraction of the mandibular third molar, causing severe postoperative complications. Many methods have been described for evaluating the relative position between the mandibular third molar and the inferior alveolar canal (IAC) on panoramic radiography and computed tomography, but conventional radiography provides limited information on the proximity of these two structures. The present study assessed the benefits of three-dimensional computed tomography (3D-CT) prior to surgical extraction of the mandibular third molar, to prevent IAN damage. Methods: This retrospective study included 4917 extractions in 3555 patients who presented for extraction of the mandibular third molars. The cases were classified into three groups, according to anatomical relationship between the mandibular third molars and the IAC on panoramic radiography and whether 3D-CT was performed. Symptoms of IAN damage were assessed using the touch-recognition test. Data were compared using the chi-square test and Fisher's exact test. Results: Among the 32 cases of IAN damage, 6 cases were included in group I (0.35 %, n = 1735 cases), 23 cases in group II (1.1 %, n = 2063 cases), and 3 cases in group III (0.27 %, n = 1119 cases). The chi-square test showed a significant difference in the incidence of IAN damage between groups I and II. No significant difference was observed between groups I and III using Fisher's exact test. In the 6 cases of IAN damage in group I, the mandibular third molar roots were located lingual relative to the IAC in 3 cases and middle relative to the IAC in 3 cases. The overlap was ${\geq}2mm$ in 3 of 6 cases and 0-2 mm in the remaining 3 cases. The mean distance between the mandibular third molar and IAC was 2.2 mm, the maximum distance 12 mm, and the minimum distance 0.5 mm. Greater than 80 % recovery was observed in 15 of 32 (46.8 %) cases of IAN damage. Conclusions: 3D-CT may be a useful tool for assessing the three-dimensional anatomical relationship and proximity between the mandibular third molar and IAC in order to prevent IAN damage during extraction of mandibular third molars.

해상운송계약(海上運送契約)에 있어서 당사자관계(當事者關係)에 관한 연구(硏究) (The Privity of the Contract Carriage of Goods by Sea)

  • 이용근
    • 무역상무연구
    • /
    • 제12권
    • /
    • pp.377-401
    • /
    • 1999
  • This study is focused on the privity of the contract of carriage of goods by sea, so to speak, privity between B/L holder and carrier by transfer of bill of lading, privity by attornment to delivery order and conflict between bills of lading and charterparty terms. Under a CIF contract, possession of the bill of lading is equivalent to possession of the goods, and delivery of the bill of lading to the buyer or to a third party may be effective to pass the property in the goods to such person. The bill of lading is a document of title enabling the holder to obtain credit from banks before the arrival of the goods, for the transfer of the bill of lading can operate as a pledge of the goods themselves. In addition, it is by virtue of the bill of lading that the buyer or his assignee can obtain redress against the carrier for any breach of its terms and of the contract of carriage that it evidences. In other words the bill of lading creates a privity between its holder and the carrier as if the contract was made between them. The use of delivery orders in overseas sales is commen where bulk cargoes are split into more parcels than there are bills of lading, and this practice gives rise to considerable difficulties. For example, where the holder of a bill of lading transferred one of the delivery orders to the buyer who presented it to the carrier and paid the freight of the goods to which the order related, it was held that there was a contract between the buyer and the carrier under which the carrier could be made liable in repect of damage to the goods. The contract was on the same terms as that evidenced by, or contained in, the bill of lading, which was expressly incorporated by reference in the delivery order. If the transferee of the delivery order presents it and claims the goods, he may also be taken to have offered to enter into an implied contract incorporating some of the terms of the contract of carriage ; and he will, on the carrier's acceptance of that offer, not only acquire rights, but also incur liabilities under that contract. Where the terms of the charterparties conflict with those of the bills of lading, it is interpreted as below. First, goods may be shipped in a ship chartered by the shipper directly from the shipowner. In that case any bill of lading issued by the shipowner operates, as between shipowner and charterer, as a mere receipt. But if the bill of lading has been indorsed to a third party, between that third party and carrier, the bill of lading will normally be the contract of carriage. Secondly, goods may be shipped by a seller on a ship chartered by the buyer for taking delivery of the goods under the contract of sale. If the seller takes a bill of lading in his own name and to his own order, the terms of that bill of lading would govern the contractual relations between seller and carrier. Thirdly, a ship may be chartered by her owner to a charterer and then subchartered by the chaterer to a shipper, to whom a bill of lading may later be issued by the shipowner. In such a case, the bill of lading is regarded as evidencing a contract of carriage between the shipowner and cargo-owners.

  • PDF

CISG 제42조 (1)항의 매도인의 책임에 관한 소고 (A Study on the Seller's Liability under Article 42(1) of the CISG)

  • 허광욱
    • 무역상무연구
    • /
    • 제60권
    • /
    • pp.47-77
    • /
    • 2013
  • The way for seller to procure the goods for selling is to produce the goods at his own factory and to buy the manufactured goods from the other company. In order to produce the goods for selling the seller have to obtain the resource from the domestic company or overseas. In the middle of producing the goods to sell, seller may breach the right of a third party based on intellectual property rights. That is to say, seller may use the machine that has not itself been patented and use a process which has been patented by a third party. Seller may manufacture the goods which themselves are subject to the third party industrial property rights. Nowadays it is stressed the importance of intellectual property rights such as a patent, brand, and design. These factors consist of the core elements of the competitiveness of the goods. Many embedded software have been used in the various sector. So the disputes regarding to the intellectual property rights is gradually increasing in number. Article 42 of CISG defines the seller's delivery obligations and liabilities in respect to third party intellectual property rights and claims. It contains a special rule for this similar kind of defective in title, which tries to provide an proper solution to the complex problems caused by such rights and claims in international transactions. When seller will apply this clause to the business fields, there are several points to which seller should give attention. First, Intellectual property is general terms in intangible property rights, encompassing both copyright and industrial property. Which matter fall within the scope of intellectual property? The scope of intellectual property can be inferred from the relevant international conventions, which are based on broad international consensus. Second, Article 42 of CISG governs the relationship between the seller and the buyer, that is to say, questions of who has to bear the risk of third party intellectual property rights. The existence of such intellectual property rights, the remedies available and the question of acquiring goods free of an encumbrances in good faith are outside the scope of the CISG. The governing law regarding to the abovementioned matters is needed.

  • PDF

역열전달해석기법에 의한 LED 조명용 무동력 냉각사이클링 방열기 성능평가 (Performance Evaluation of a Thermo Siphon Type Radiator for LED Lighting System by using an Inverse Heat Transfer Method)

  • 김은희;김흥규;서광석;이민규;조종두
    • 소성∙가공
    • /
    • 제20권7호
    • /
    • pp.473-478
    • /
    • 2011
  • In this study, the performance of a thermo siphon type radiator made of copper for LED lighting system was evaluated by using an inverse heat transfer method. Heating experiments and finite element heat transfer analysis were conducted for three different cases. The data obtained from experiments were compared with the analysis results. Based on the data obtained from experiments, the inverse heat transfer method was used in order to evaluate the heat transfer coefficient. First, the heat transfer analysis was conducted for non-vacuum state, without the refrigerant. The evaluated heat transfer coefficient on the radiator surface was 40W/$m^2^{\circ}C$. Second, the heat transfer analysis was conducted for non-vacuum state, with the refrigerant, resulting in the heat transfer coefficient of 95W/$m^2^{\circ}C$. Third, the heat transfer analysis was conducted for vacuum state, with refrigerant. For the third case, the evaluated heat transfer coefficients were 140W/$m^2^{\circ}C$. Third, the heat transfer analysis was conducted for vacuum state, with refrigerant. For the third case, the evaluated heat transfer coefficients were 140W/$m^2^{\circ}C$ for the radiator body, 5W/$m^2^{\circ}C$. Third, the heat transfer analysis was conducted for vacuum state, with refrigerant for the rising position of radiator pipe, 35W/$m^2^{\circ}C$. Third, the heat transfer analysis was conducted for vacuum state, with refrigerant. For the highest position of radiator pipe, and 120W/$m^2^{\circ}C$ for the downturn position of radiator pipe. As a result of inverse heat transfer analysis, it was confirmed that the thermal performance of the current radiator was best in the case of the vacuum state using the refrigerant.

교량공사 제3자 피해 손실에 의한 리스크 분석 연구 (A Study on Bridge Construction Risk Analysis for Third-Party Damage)

  • 안성진;남경용
    • 한국건축시공학회지
    • /
    • 제20권2호
    • /
    • pp.137-145
    • /
    • 2020
  • 최근 교량은 장대화, 신공법의 도입에 따른 위험요인의 증가로 교량공사에서의 철저한 안전 및 리스크 관리 체계가 필요하다. 공사 현장 주변에 있는 발주자 건설공사 관련자 및 공사와 관련이 없는 제 3자의 기존 재산에 손해를 발생시킬 수 있어 제3자 피해 손실로 인한 리스크가 명확히 분석되어야 함에도 불구하고 연구가 미비한 실정이다. 본 연구는 교량건설 사업에 대한 국내 주요 보험사의 과거 보험료 지급 실적을 토대로 실제 교량 건설에서 제3자 피해 손실로 인한 손실에 대한 교량건설 특성에 따른 리스크 요인을 분석하고, 정량화된 예측 손실 모델을 개발하고자 하였다. 정량적 교량건설 손실모형 개발을 위해 사고 건당 보험지급액을 총공사비로 나눈 손실비율을 종속변수로 선정하였고, 상부구조, 하부구조, 홍수 및 도급순위가 교량건설 중 제3자 피해에 의한 손실비율에 영향을 미치는 지표로 나타났다. 도출된 결과는 건설프로젝트에 대한 손실 평가 모델 개발에 기존의 프로젝트 내부에서 발생한 손실과 더불어 제3자 피해손실을 고려함으로써 더불어 균형 있는 리스크 평가에 필수적인 지침으로 활용할 수 있다.

기체 상태에서의 오존과 아황산가스의 반응연구 (The Kinetics Study of Ozone with Sulfur Dioxide in the Gas Phase)

  • 권영식
    • 대한화학회지
    • /
    • 제35권2호
    • /
    • pp.111-118
    • /
    • 1991
  • 기체 상태의 오존(0.5 torr)과 이산화황간의 반응속도를 연구하였다. 이산화황은 7∼22 torr 의 압력범위에서 90∼155$^{\circ}$C의 온도영역에서 반응시켰다. 오존과 이산화황의 반응속도는 이산화탄소와의 반응보다 빨리 진행되었다. 오존과 이산화황의 반응속도식은 -d(O$_3 )/dt = k _0 (SO _2 )(M)(O _3)+2k _1(SO_2 )(O _3$)였다. 이 속도식의 첫 항은 3분자 반응으로 낮은 온도에서 우세하게 진행되었으며, 속도상수 k$_0 =(9.35{\pm}8.6){\times}10^9e^{-(11.05{\pm}2.04)kcal/RT}(M^{-2}s^{-1}$)이다. 속도식의 두번째 항은 2분자 열분해 반응으로부터 유도된 주된 반응으로 속도상수 k$_1=(1.53{\pm}1.5){\times}10^{11}e^{-22.7 kcal/RT}$이다. 전 반응차수는 주로 2차 반응이며 3차 반응과 복합반응으로 진행되었다.

  • PDF

사석잠제와 Stokes 3차파와의 비선형간섭에 관한 연구 (Nonlinear Interaction between the Permeable Submerged Breakwater and Third Order Stokes Waves)

  • 정연태
    • 한국수자원학회논문집
    • /
    • 제31권3호
    • /
    • pp.223-234
    • /
    • 1998
  • 파랑제어 및 표사제어라고 하는 해안·항만구조물의 원래의 기능 이외에 해양·해안환경의 유지·개선의 기능까지도 갖춘 투과성잠제에 의한 비선형파랑변형을 해석하였다. 해석법으로서 Stokes 3차파에 기초한 섭동전개법과 경계요소법을 병용하는 주파수영역해석법을 처음으로 투과성잠제의 파랑변형에 적용하였다. 투과층내의 유체운동의 저항에는 Dupuit-Forchheimer의 저항식을 적용하며, Lorentz의 등가일원리에 기초하여 얻어지는 등가선형마찰계수의 산정식을 공간적분만의 형태로 나타내었다. 본 이론의 검증을 위하여 수리모형실험을 실시하였으며, 얻어진 수리모형실험결과는 수치해석결과와 잘 일치하므로 그의 타당성이 검증되었고, 본 해석결과가 Stokes 2차파에 기초한 결과보다도 더 정확성을 가진다는 것을 확인할 수 있었다.

  • PDF