• 한국수자원학회논문집
• /
• 제33권1호
• /
• pp.31-38
• /
• 2000

수문변량 사이의 관계는 대부분 비선형 관계를 보이고 있다. 일반적으로 이런 비선형 관계는 어떤 선행하는 명백한 하나의 함수적인 형태로 표현할 수 없는 것이 일반적이다. 본 논문에서는, 비매개변수적 다변량 회귀분석 방법을 지역적으로 가중된 다항식을 이용하여 비선형 예상 함수를 추정하였다. 지역적으로 가중된 다항식은 추정치 각 점에서의 인접한 이웃자료를 가지고 목적 함수를 테일러 급수 확장을 통하여 고려하였다. 이런 비매개변수적 회귀분석을 실용성을 Great Salt Lake의 격주 체적자료에 대한 단기간 예측을 통하여 보여주었다.

• 한국발생생물학회지:발생과생식
• /
• 제23권4호
• /
• pp.305-311
• /
• 2019

Small intestine has a structure called villi that increases the mucosal surface area for nutrient absorption. Intricate and tight epithelial-mesenchymal interactions are required for villi development. These interactions are regulated by signaling molecules, physical forces, and epithelial deformation. Signaling molecules include hedgehog (Hh), bone morphogenetic protein (BMP) and Wnt ligands. The Hh ligand is expressed from the epithelium and binds to the underlying mesenchymal cells, resulting in aggregation into mesenchymal clusters. The clusters express BMP and Wnt ligands to control its size and spacing between clusters. The clusters then form villi. Despite the fact that the villi formation is studied extensively, we do not have a complete understanding. In addition, the recent study shows there is a great relationship between the overexpression of the Hh signal and development of cancer in the gastrointestinal tract. Therefore, signaling between epithelial and mesenchymal cells and their physical interactions will be discussed on this review.

• 응용통계연구
• /
• 제4권1호
• /
• pp.33-45
• /
• 1991

변화시점 모형은 지금까지 한 시점에서 단 한 개의 관측자료를 갖는 모형만 생각해 왔다. 이러한 모형을 확장시켜 각 시점에 한 개 이상의 관측자료를 갖는 변화시점 모형을 생각한다. 이러한 모형에서 비모수적인 단측 그리고 양측 검정법을 찾았다. 검정 통계량은 지금까지 소개된 검정 통계량 형태를 확장시킨 형태이고 이들의 귀무가설 분포를 구하여 보았다. 또한 Monte Carlo연구를 통해 이들의 검정력을 비교해 보았다.

• Journal of Chest Surgery
• /
• 제19권3호
• /
• pp.381-384
• /
• 1986

Pulmonary aspergillosis is a relatively rare disease in Korea. Immune suppressive patients, resulting from misuse or long term therapy of antibiotics, steroid and anticancer chemotherapeutics tend to be vulnerable to pulmonary aspergillosis. This study is made to illustrate the clinical features, preoperative diagnosis and surgical role in the management is this diseases. In retrospective study of operative cases from May 1980 through July 1986, 10 cases were analysis. Hemoptysis and blood tinged sputum were the most common chief complaints. Major underlying pathology was cavitary lesion or bronchiectasis caused by pulmonary tuberculosis [5 cases]. 2 cases were disseminated form due to immune suppression. Anatomic location of lesion was in the upper lobe in half case. Systemic antifungal agent is helpful for invasive aspergillosis and Resection is the treatment of choice for localized fungus balls and symptomatic localized forms.

• Kyungpook Mathematical Journal
• /
• 제55권2호
• /
• pp.345-353
• /
• 2015

Subnormality of bounded weighted composition operators on $L^2({\Sigma})$ of the form $Wf=uf{\circ}T$, where T is a nonsingular measurable transformation on the underlying space X of a ${\sigma}$-finite measure space (X, ${\Sigma}$, ${\mu}$) and u is a weight function on X; is studied. The standard moment sequence characterizations of subnormality of weighted composition operators are given. It is shown that weighted composition operators are subnormal if and only if $\{J_n(x)\}^{+{\infty}}_{n=0}$ is a moment sequence for almost every $x{{\in}}X$, where $J_n=h_nE_n({\mid}u{\mid}^2){\circ}T^{-n}$, $h_n=d{\mu}{\circ}T^{-n}/d{\mu}$ and $E_n$ is the conditional expectation operator with respect to $T^{-n}{\Sigma}$.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2003년도 추계 학술대회논문집
• /
• pp.126-131
• /
• 2003

A series of computational simulations have been carried out for supersonic flows in a scram jet engine with and without a cavity. Transverse injection of hydrogen, a simplest form of fuel supply, is considered in the present study with the injection pressure varying from 0.5 to 1.5 MPa. The corresponding equivalence ratios are 0.167 - 0.50. The work features detailed resolution of the flow dynamics in the combustor, which was not typically available in most of the Previous studies. In particular, oscillatory flow characteristics are captured at a scale sufficient to identify the underlying physical mechanisms. Much of the flow unsteadiness is related not only to the cavity, but also to the intrinsic unsteadiness in the flowfield. The interactions between shock waves and shear layer may cause a large excursion of flow oscillation. The role of the cavity and injection pressure are examined systematically.

• International Journal of Reliability and Applications
• /
• 제2권4호
• /
• pp.253-262
• /
• 2001

A k-out-of-n standby system is considered where all of its components are s-independent and classified either working or cold standby connected with imperfect switches. The probability density function of the life length for this system is established in closed form, when the underlying components have constant failure rates. Also the reliability function of the system is derived. Finally, the reliability functions for one, two and three out of four systems are deduced for perfect or imperfect switches and identical or non-identical constant failure rates for working and standby components.

• Molecules and Cells
• /
• 제41권5호
• /
• pp.373-380
• /
• 2018

Synapses and neural circuits form with exquisite specificity during brain development to allow the precise and appropriate flow of neural information. Although this property of synapses and neural circuits has been extensively investigated for more than a century, molecular mechanisms underlying this property are only recently being unveiled. Recent studies highlight several classes of cell-surface proteins as organizing hubs in building structural and functional architectures of specific synapses and neural circuits. In the present minireview, we discuss recent findings on various synapse organizers that confer the distinct properties of specific synapse types and neural circuit architectures in mammalian brains, with a particular focus on the hippocampus and cerebellum.

• 산업공학
• /
• 제2권2호
• /
• pp.51-62
• /
• 1989

A computer-aided simulation modeling system has been developed to allow the automatic construction of complete discrete simulation models for queueing systems. Three types of knowledge are used in the specification and construction of a simulation modeling: Knowledge of queueing system, simulation modeling, and a target simulation language. This knowledge has been incorporated into the underlying rule base in the form of extraction and construction rule, and implemented via the expert system building tool, OPS5. This paper suggested a knowledge based approach for automatic programming to enable a user who lacks modeling knowledge and simulation language expertize to quickly build executable models.

• Archives of Plastic Surgery
• /
• 제32권5호
• /
• pp.645-648
• /
• 2005

Cutaneous horn is a morphologic designation for a projectile, conical, dense hyperkeratotic nodule that resembles the horn of an animal. The lesion varies in size from only a few millimeters to several centimeters, in color(white or yellowish) and in form (straight, curved, or twisted). It arises from a wide range of epidermal lesions, which include benign lesions, premalignant lesions and malignant lesions. An 83-year-old women came to our clinic with a giant cutaneous horn on the right chin and a small horn on the left upper eyelid. The patient had no palpable cervical lymph node. A wide elliptical skin incision was made and the horn was totally excised. In pathology, the giant cutaneous horn on the right chin revealed a moderately differentiated squamous cell carcinoma with subcutis invasion at its base. "Giant cutaneous horns" have often been associated with invasive squamous cell carcinoma. Cutaneous horns are common lesions usually found on the face, rarely larger than 2 cm. As large cutaneous horns are often associated with underlying malignancy, histopathologic examination of the base of the lesion is necessary to rule out carcinoma and full excision is recommended.