• 천문학회보
• /
• 제37권1호
• /
• pp.46.1-46.1
• /
• 2012

A unique ensemble of datasets is available for the AKARI North Ecliptic Pole (NEP) field, having being observed virtually across the whole electromagnetic spectrum. We have undertaken a study of radio sources in the NEP field and in particular radio-loud AGN. We present preliminary results concerning the identification of these radio-loud AGN using a host of different selection criteria. We aim to study the host galaxies of these systems within the current framework of galaxy evolution and the role that AGN play in it.

• 대한수학회보
• /
• 제61권1호
• /
• pp.135-145
• /
• 2024

We consider a function-field analogue of Dirichlet series associated with the Goldbach counting function, and prove that it can, or cannot, be continued meromorphically to the whole plane. When it cannot, we further prove the existence of the natural boundary of it.

• Radiation Oncology Journal
• /
• 제20권1호
• /
• pp.24-33
• /
• 2002

목적 : 유방보존 수술 후 행하는 방사선치료인 2문 대칭조사(two tangential field technique)시 나타나는 선량분포의 불균일성을 효과적으로 개선하기 위하여, multistatic fields의 사용법과 공용보상체 사용법을 제시하고 평가하였다. 대상 및 방법 : 1) Multistatic field 방법 3차원의 치료계획용 software (RTP)를 이용하여, wedge를 사용한 2문 대칭 조사의 최적의 치료계획을 시행한 후 beam's eye view상에서 과조사가 일어나는 부분을 가리워 주도록 blocked field를 설계하고, 그 beam에 대칭되는 beam을 만들었다. 기존의 2개의 tangential field와 추가된 field의 weighting을 최적의 선량분포를 갖도록 조절하였다. 2) 공용보상체 사용법 : 1999와 2000년에 본원에서 whole-breast radiotherapy를 받은 환자 20명의 유방의 크기를 측정하고 평균하여 표준 유방 모델을 만들었다. 이 모델에 대하여 공용보상체를 설계하고, 설계된 공용보상체의 geometry를 RTP에 입력한 후 환자의 치료 계획을 수행하였다. 2문 대칭조사 치료 계획과, multistatic fields의 경우 그리고 공용 보상체를 사용한 경우의 치료계획에서의 불균일도(DII : 처방선량의 $95-105\%$를 벗어나는 PTV의 부피의 백분율), 최대선량 값$(D_{max})$ 그리고 등가선량 곡선을 각각 비교하였다. 결과 : Multistatic field 방법은 DII의 평균값을 $14.6\%$ (p value<0.000) 낮추고 $D_{max}$를 $4.7\%$ (p value<0.000) 낮춤으로써, 전통적인 2문 대칭 조사법보다 우수한 방법으로 확인되었다. 반면에 공용보상체의 사용은 평균 DII를 $3.7\%$ 낮추지만(p value=0.260) 평균 $D_{max}$는 거의동일 하여($0.3\%$ 감소, p value=0.867), 전통적인 방법보다 우수성이 크게는 없는 것으로 평가되었다. 그러나 환자의 체곡선이 보상체와 잘 일치하는 경우에는 DII가 $18\%$까지 감소하였다. 결론 : Multistatic field 방법은 모든 환자에 대하여 선량분포의 균일성을 전반적으로 향상시키는 효과적인 방법으로 평가되는 반면 공용보상체의 사용은 보상체의 크기가 환자의 체 윤곽과 잘 일치하는 경우만 효과적으로, 적용의 범위에는 한계가 있는 방법으로 평가되었다.

• Asia pacific journal of information systems
• /
• 제22권4호
• /
• pp.31-49
• /
• 2012

In this essay, we problematize the problematics of the KMIS SOLOMO research agenda. We propose that the SOLOMO agenda is a conditioned product of the various assumptions, biases, premises, and presuppositions that the field of IS collectively succumbs to and shares, and thus needs to be problematized to arrive at a new set of research questions for the field. The problematization begins with the ontology that underlies the agenda. We argue that the agenda is largely drawn from a dichotomic, deep ontology of Human vs. Technology. While such ontology is neither right nor wrong in its own right, we suggest it is what underlies and influences the field's whole mode of inquiry including its research agenda. We propose an alternative ontology, the Actor-Network Theory (ANT), which as a flat ontology provides a radically different set of research questions for the field. Next we take issue with the teleology of the SOLOMO agenda, and suggest that the telos of the agenda, and of the field of IS and the whole of Management discipline together, are anchored upon the capitalist episteme so that it creates a significant hole in its teleological scape. While not in any sense calling for an ideological demagogue, we propose that the field of IS should open itself to an alternative teleology including a leftist perspective. We draw upon the Critical Management Studies (CMS) to explore how further problematization can be made on the SOLOMO agenda, generating questions about its performativity, denaturalization, and reflexivity. As a result of the discussions, a list of new problematized research questions for the SOLOMO agenda is generated. In the end we state the motivation of the essay and call for a critical refurbishing of the field of IS.

• 한국광학회지
• /
• 제31권6호
• /
• pp.304-313
• /
• 2020

조리개가 제 2거울에 있는 inverse Cassegrain 광학계에서 비축시야를 사용하면, 이 2반사경계는 넓은 시야를 가지는 대물광학계로 사용할 수 있다. 하지만 이 전통적인 회전대칭 구조의 반사경계는 설계변수의 수가 너무 적기 때문에 수차보정에 한계가 있다. 이 연구에서는 조리개와 제 2거울을 별도로 횡이동시켜 성능을 개선한 새로운 2반사 광학계를 설계하였다. 새로운 설계변수를 사용하여 5차 코마와 비점수차에 대한 보정이 개선되었으며, 시야 전체에서 보다 좋은 수차균형을 얻을 수 있었다. 새로 설계된 비축시야 2반사경계는 회전대칭 구조의 통상적인 2반사경계와 비교하여 spot의 크기가 1/2 수준으로 줄어들었으며, 개선의 효과가 시야 전체에 고르게 나타나고 있다.

• 한국생산제조학회지
• /
• 제6권4호
• /
• pp.39-45
• /
• 1997

Shadow moire topography has been used as a noncontact method for measuring the 3-D shapes of objects. The moire fringes are results from the superposition of a master grating and its shadow projected on the surface of an object. But in case of the classical shadow moire method, in general, the resolution is a few tenths of millimeter. It is difficult to use a phase -shifting method in shadow moire because it is impossible to obtain uniform phase shifts on the whole field. But in this study , We introduce a phase-shifting method to improve the resolution of the classical shadow moire method. This method is based on the fact that if the depth of object is much less than the distance between the observer and the master grating, the phase shifts are almost uniform on the whole field area. Finally, we applied this new phase-shifting method to the measurement of the 3-D shape of a coin.

• 한국초전도저온공학회지:초전도와저온공학
• /
• 제11권2호
• /
• pp.23-29
• /
• 2009

The unique features of HTS offer opportunities and challenges to a number of applications. In this paper we focus on NMR and MRI magnets, illustrating them with the NMR/MRI magnets that we are currently and will shortly be engaged: a 1.3 GHz NMR magnet, an "annulus" magnet, and an $MgB_2$whole-body MRI magnet. The opportunities with HTS include: 1) high fields (e.g., 1.3 GHz magnet); 2) compactness (annulus magnet); and 3) enhanced stability despite liquid-helium-free operation ($MgB_2$whole-body MRI magnet). The challenges include: 1) a large screening current field detrimental to spatial field homogeneity (e.g., 1.3 GHz magnet); 2) uniformity of critical current density (annulus magnet); and 3) superconducting joints ($MgB_2$magnet).

• Journal of Mechanical Science and Technology
• /
• 제16권2호
• /
• pp.175-181
• /
• 2002

A new polariscope system involving two rotating optical elements and a digital camera for whole field fringe analysis allows automated data to be acquired quickly and efficiently. The developed phase measuring technique that uses eight images through a circular polariscope is presented for the digital measurement of isochromatics and isoclinics, respectively, from photoelastic fringes in a circular disk under diametric compression. Isochromatics can directly be obtained using wrapped isoclinic phases calculated by the arc tangent operator which is the four-quadrant operator from -$\pi$ to $\pi$. It is not required to unwrap isoclinic phases for the calculations of isochromatics. Unwrapped isoclinics are directly determined from isochromatic parameters. Distributions of digitally determined isoclinics are in close agreement to manual measurements. The errors which would appear in unwrapping process of isoclinics can be avoided in the determination of isochromatics.

• 한국연초학회지
• /
• 제5권1호
• /
• pp.25-33
• /
• 1983

This study was carried out to investigate the transplanting time, optimum fertilization and harvesting method, chemical contents and physical properties of burley tobacco in paddy field. The results obtained as follows. 1. It is recommendable to transplant after March. 29 to escape the frost injury. By reducing compound fertilizer and whole plant stalk curing, advanced the. last priming date by 5-8 days. 2. Total alkaloid, total nitrogen and phosphorus contents of cured leaf was comparable to those of upland-produce(1 tobacco, but potassium and chloride contents some what high. 3. Filling power and combustibility was also comparable to upland, and filling power was increased by reducing fertilizer and whole plant stalk curing. 4. In the 20o reducing fertilizer-5 Primings volt. the yield was some what decreased, but visual quality and value per 10a were high. 5. The total raw income of tobacco and rice cropping was increased 124~170% than that of rice cropping.

• 산업공학
• /
• 제16권spc호
• /
• pp.70-75
• /
• 2003

There have been dramatic technology changes in telecommunication sector during last two decades. New application services like the introduction of international mobile services, fiber optical home services and satellite personal services are expected to play a major role in the whole field of telecommunication services. In the users' viewpoint, the proper selection and the efficient application of the specific telecommunication service among the various alternatives at hand are recognized as principle means for ensuring the whole business competitiveness. Despite the definite need for the telecommunication service selection strategies, very few researches have been reported in this field. In this paper, attempts are made to identify the companies' decision factors considered in selecting the telecommunication services, to draw the strategic dimensions and categorize each company with respect to the identified dimensions, and to finally find the characteristics of each strategic group in selecting the telecommunication service.