• 대한기계학회논문집
• /
• 제17권8호
• /
• pp.1883-1897
• /
• 1993

Interactive computer-aided analysis of mechanical systems has recently been undergoing an evolution due to highly efficient computer graphics. The industrial implementation of state-of-the-art analytical developments in mechanisms has been facilitated by computer-aided design packages because these rigid-body mechanism analysis programs dramatically reduce the time required for linkage design. This paper proposes a component modular approach to computeraided kinematic motion analysis for general planar multiloop mechanisms. Most multiloop mechanisms can be decomposed into serveral components. The kinematic properties (position, velocity, and acceleration) of every node can then be determined from the kinematic analysis of the corresponding component modules by a closed-form solution procedure. In this paper, 8 types of modules are defined and formulations for kinematic analysis of the component modules are derived. Then a computer-aided kinematic analysis program is developed using the proposed approach and the solution procedure of an example shows the effectiveness and accuracy on the approach.

• Journal of Microbiology and Biotechnology
• /
• 제14권5호
• /
• pp.967-971
• /
• 2004

The kinetics of sulfite uptake were examined in a wild-type laboratory strain of Saccharomyces cerevisiae to determine if carrier-mediated sulfite uptake involved a proton symport, as previous studies on sulfite uptake have suggested both an active process and facilitated diffusion. Accumulation of intracellular sulfite was initially rapid and linear up to 50 sec. Uptake was saturable at final concentrations equal to or greater than 3 mM sulfite, and increased 2-fold in the presence of 2% glucose. Uptake was significantly reduced in cells pretreated with 100-500 $\mu$M carbonyl cyanide mchlorophenylhydrazone (CCCP) or 2,4-dinitrophenol (DNP), both of which dissipate proton gradients. Uptake was also significantly inhibited in the presence of 1 mM arsenate, an inhibitor of ATP synthesis. Extracellular alkalization was observed in cells incubated with 1-2 mM sulfite in a weak tartrate buffer at pH 3.5 and 4.5. These findings suggest that the bisulfite ion, $HSO_3^-$, an anionic form of sulfite, is taken up by a carrier-mediated proton symport. A met16 sull sul2 mutant, impaired in both sulfite formation and sulfate uptake, was found able to grow on a medium with sulfite as the sole Sulfur source, indicating that the sulfate transporters Sul1p and Sul2p are not required for sulfite uptake.

• 무역상무연구
• /
• 제19권
• /
• pp.169-190
• /
• 2003

Uniform Computer Information Transactions Act (UCITA) for e-commerce in non-UCC and non-UETA transactions, promulgated in 1999. The Act Drafted by the National Conference of Commissioners on Uniform State Laws. UCITA applies to contracts to license or buy software, contracts to create computer programs, contracts for on-line access to databases and contracts to distribute information over the Internet. UCITA does not apply to goods such as television sets, stereo equipment, airplanes or traditional books and publications. Goods generally remain subject to UCC Article 2 or Article 2A. Many transactions may include more than computer information. If that transaction covers non-goods subject matter, UCITA applies only to the part of the transaction which is computer information and other law applies to the other subject matter. In the event the other subject matter is goods, UCC Article 2 or 2A applies to the goods subject matter and UCITA applies to the computer information part. UCITA is coordinated with existing Articles 2 and 2A, so coverage of each to part of the transaction will be facilitated. With respect to other subject matter (primarily services) UCC Articles 2 and 2A have worked in mixed transactions with the common law applicable to the services.

• 건축역사연구
• /
• 제21권5호
• /
• pp.47-56
• /
• 2012

This research focuses on the role of Giovanni Marinioni during the formation of the modern cartography and cadastre during the 18th century. Initial study began with Giambattista Nolli's Roman map noticing not much information was available to acknowledge his activities during his Milan period before the departure to Rome. It became evident that Marinoni was a key person to understand the complex circumstances in which the professional training and formation of Giambattista Nolli took place as later worked as an anonymous intern during the elaboration of Theresian Cadastre of Milan. The other important figures are Leandro Anguissola and Giovanni Filippini. Anguissola's position and precedent work facilitated Marinoni's multidisciplinary activities that he had performed in Vienna and Milano in the field of making urban maps of those two cities. On the other hand, Filippini not only collaborated with Marinoni but also introduced Nolli in the field of cartography. These activities show transitional and dual aspects that characterized the period in which important irreversible changes that occur during the reign of Habsburg empire and in the rest of the Europe toward the formation of modern society and state. Marinoni's theories and praxis greatly influenced Nolli's later commitment under the Savoia and later on the elaboration of the 'Pianta Grande di Roma' in 1748.

• Membrane and Water Treatment
• /
• 제2권4호
• /
• pp.207-223
• /
• 2011

Supported Liquid Membranes (SLMs) have been widely studied as feasible alternative to traditional processes for separation and purification of various chemicals both from aqueous and organic matrices. This technique offers various advantages like active transport, possibility to use expensive extractants, high selectivity, low energy requirements and minimization of chemical additives. SLMs are not yet used at large scale in industrial applications, because of the low stability. In the present paper, after a brief overview of the state of the art of SLM technology the facilitated transport mechanisms of SLM based separation is described, also introducing the small and the big carrousel models, which are employed for transport modeling. The main operating parameters (selectivity, flux and permeability) are introduced. The problems related to system stabilization are also discussed, giving particular attention to the influence of membrane materials (solid membrane support and organic liquid membrane (LM) phase). Various approaches proposed in literature to enhance SLM stability are also reviewed. Modification of the solid membrane support, creating an additional layer on membrane surface, which acts as a barrier to LM phase loss, increases system stability, but the membrane permeability, and then the flux, decrease. Stagnant Sandwich Liquid Membrane (SSwLM), an implementation of the SLM system, results in both high flux and stability compared to SLM. Finally, possible large scale applications of SLMs are also reviewed, evidencing that if the LM separation process is opportunely carried out (no production of byproducts), it can be considered as a green process.

• 한국수학사학회지
• /
• 제18권1호
• /
• pp.11-32
• /
• 2005

본 논문은 조선시대의 수학교육을 조선왕조실록에 나타난 기록을 중심으로 하여 연구하였다. 조선시대 수학은 기록에 나타난 바와 같이 기초적인 산수교육 수준에 머물러 있다. 조선시대의 수학은 중인계급을 통하여 발전되었으며 토지측량, 세제, 역법 등을 주로 다루는 실무를 담당하기 위하여 산학교육이 이루어졌다. 조선시대 수학은 수학사적 측면에서는 중요한 부분을 차지하고 있지만 현대 수학으로 발전시키지 못한 문제들을 안고 있다. 이러한 이유들에 대하여도 고찰하였다.

• 한국정보통신학회논문지
• /
• 제8권2호
• /
• pp.310-323
• /
• 2004

In this paper, we extend the multiple time scale control framework to window-based congestion control, in particular, TCP This is performed by interfacing TCP with a large tine scale control nodule which adjusts the aggressiveness of bandwidth consumption behavior exhibited by TCP as a function of "large time scale" network state. i.e., conformation that exceeds the horizon of the feedback loop as determined by RTT Our contribution is threefold. First, we define a modular extension of TCP-a function call with a simple interface-that applies to various flavors of TCP-e.g., Tahoe, Reno, Vegas and show that it significantly improves performance. Second, we show that multiple time scale TCP endows the underlying feedback control with preactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of three traffic control dimensions-tracking ability, connection duration, and fairness-on performance. Performance evaluation of multiple time scale TCP is facilitated by a simulation bench-mark environment which is based on physical modeling of self-similar traffic.

• BMB Reports
• /
• 제52권2호
• /
• pp.127-132
• /
• 2019

Cells must fine-tune their gene expression programs for optimal cellular activities in their natural growth conditions. Transcriptional memory, a unique transcriptional response, plays a pivotal role in faster reactivation of genes upon environmental changes, and is facilitated if genes were previously in an active state. Hyper-activation of gene expression by transcriptional memory is critical for cellular differentiation, development, and adaptation. TREM (Transcriptional REpression Memory), a distinct type of transcriptional memory, promoting hyper-repression of unnecessary genes, upon environmental changes has been recently reported. These two transcriptional responses may optimize specific gene expression patterns, in rapidly changing environments. Emerging evidence suggests that they are also critical for immune responses. In addition to memory B and T cells, innate immune cells are transcriptionally hyperactivated by restimulation, with the same or different pathogens known as trained immunity. In this review, we briefly summarize recent progress in chromatin-based regulation of transcriptional memory, and its potential role in immune responses.

• 한국결정성장학회지
• /
• 제29권1호
• /
• pp.19-23
• /
• 2019

The PMMA (polymethyl methacrylate)/clay nanocomposites were synthesized by in situ radical polymerizations with different clay contents (3 and 7 wt%) using microwave heating. The nanostructure, optical, and thermal properties of the synthesized PMMA/clay nanocomposites were measured by XRD, TEM, AFM, UV-vis, and TGA. It was found that the intercalated- or exfoliated structure of PMMA/clay nanocomposites was strongly dependent on the content of clay. Thus, the imposition of microwave-assisted polymerization facilitated a delamination process of layered silicates to achieve exfoliation state of interlayer distance. The PMMA/3 wt% C10A nanocomposite with well-dispersed and exfoliated clay nano-layers showed the good optical transparency similar to pure PMMA in this study. The thermal decomposition rates of the PMMA/clay nanocomposites become to be lower compared to that of the pure PMMA, indicating the intercalated- or exfoliated inorganic silicate has high thermal stability. A possible reason is that the thermally segmental motion of PMMA polymer into inorganic silicate interlayer spacing has increased the thermal stability of the PMMA/clay nanocomposites.

• 수완나부미
• /
• 제10권1호
• /
• pp.35-61
• /
• 2018

This paper explores the influence of Arab culture on the culture of Bugis-Makassar, the two major ethnic groups in South Sulawesi, Indonesia, particularly after their Islamization in the early 17^th century. The paper argues that since then, the on-going process of Islamization in the region has also brought a continuous flow of ideas and cultural practices from Mecca to Indonesia by means of the hajj pilgrims, Arab traders, and the establishment of Islamic educational institutions that emphasized the teaching and use of Arabic language in education. These factors, among others, have facilitated a cultural inflow which enabled cultural practices borne of West Asia (Middle East) to be integrated into local customs and beliefs. The paper particularly depicts the most observable forms of Arabic cultural integration, acculturation, and assimilation into the Bugis-Makassar culture such as the use of Arabic in Islamic schools and religious sermons; the Arab-style dressing by religious scholars, teachers, and students; the wearing of the hijab (head cover) by women; and the change of people's names from local into Arabic. By utilizing the historical and anthropological approach, this paper investigates this dynamic process of adaptation and integration of a foreign culture that first came through the Islamization of a local culture, exploring the role of an Islamic missionary and educational institutions in mediating and maintaining such cultural integration processes.