• Animal cells and systems
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• 제5권4호
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• pp.313-317
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• 2001

The sequential assessment model describes a fight between two conspecific as an ongoing statistical sampling process, which makes it possible to predict fight length or repetition number of a behavioral element depending on relative RHP (resource holding potential: e.g. weight or fighting ability). We staged contests between males of common freshwater gobies to test some predictions of this model. Fights proceeded in a consistent sequence of phases. Most contests began with two contestants adopting lateral display, and then escalated to intense physical contacts. The length of contests was negatively correlated with weight difference between the contestants. The duration of complete phases was, however, independent of weight, and the prior information gained during complete phases did not appear to affect subsequent phases of the fight. Our results show that the contests of common freshwater gobies are well predicted by the sequential assessment model.

• 아동학회지
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• 제20권3호
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• pp.3-17
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• 1999

Maternal sensitivity and infant temperament were studied in relation to infant attachment security. Subjects were 47 one-year-old infants anti their mothers from intact upper-middle class families. Mothers sorted the Attachment Q-set (Waters, 1987, version 3.0) and filled out the Toddlers Temperament Questionnaire(Chu, 1992). Maternal sensitivity was observed in the home for two 3-hour sessions, and observers completed the Maternal Behavior Q-set(Pederson, Moran et al., 1990). Attachment security scores of the infants, using criterion scores developed with Korean infants, were 42, which is comparable to Previous studies. Infants who were securely attached to mothers showed more secure-based behaviors and compliance, enjoyed physical contacts, and showed less fussy/difficult behaviors with mothers. Mothers of girls were observed to be more sensitive to their infants' signals than mothers of boys. Maternal sensitivity scores were not related to infant security scores. However, maternal sensitivity was related to less compliance to mothers for boys.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.93-93
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• 2003

Tungsten and tungsten heavy alloys have widespread application as radiation shielding devices and heavy duty electrical contacts. High density and good room temperature mechanical properties have generated interest in evaluating tungsten and tungsten alloys as kinetic energy penetrators against armor. Nowdays ultra fine-grained tungsten powders are in great interest because higly dense structures can be obtained at low temperature, pressure and lower sintering time. Several physical md chemical methods are available for the synthesis of nanometric metal Powders: ball milling, laser abalation, vapor condensation, chemical precipitation, metallic wire explosion i.e. However production rates of the above mentioned methods are low and further efforts are needed to find out large-scale synthesis methods. From this point of view solid state combustion method ( known as SHS) represents undoubted interest.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.255.2-255.2
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• 2014

Electrode erosion is indispensable for atmospheric plasma systems, as well as for switching devices, due to the high heat flux transferred from arc plasmas to contacts, but experimental and theoretical works have not identified the characteristic phenomena because of the complex physical processes. Our investigation is concerned with argon free-burning arcs with anode erosion at atmospheric pressure by computational fluid dynamics (CFD) analysis. We are also interested in the energy flux and temperature transferring to the anode with a simplified unified model of arcs and their electrodes. In order to determine two thermodynamic quantities such as temperature and pressure and flow characteristics we have modified Navier-Stokes equations to take into account radiation transport, electrical power input and the electromagnetic driving forces with the relevant Maxwell equations. From the simplified self-consistent solution the energy flux to the anode can be derived.

• 펄프종이기술
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• 제35권2호
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• pp.6-11
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• 2003

Refining process is of critical importance unit process for papermaking that influences freeness as well as many mechanical and physical properties of paper. Refining is the process that requires extensive amount of electrical energy. Thus it is required to evaluate the refining process in terms of its influence on fiber and paper properties as well as its effect on energy consumption. In this study, to evaluate the efficiency of refining process the theory of inch contacts has been employed, and the influence of refining processes on fiber and paper properties has been determined and discussed.

• 보건행정학회지
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• 제30권2호
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• pp.139-141
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• 2020

Coronavirus disease 2019 (COVID-19) is currently in progress. Although it is difficult to predict the end of currently increasing COVID-19, it is expected to last for a long time. The COVID-19 is making a lot of changes. Due to physical distancing and living distancing, non-contacts such as wearing facial masks, online lectures, online medical services, telecommuting, and telemarketing are becoming common. In the era of post-COVID-19, online and offline will coexist. Many countries following China's lockdown strategy, which is agreed with the World Health Organization, should be changed to Taiwan's facial mask strategy for reducing the economic problems. The prolonging COVID-19 will add to the economic difficulties, and the US-China confrontation will be difficult to rebound the global economy. COVID-19, such as plaque, smallpox, and Spanish influenza, will be a historical momentum. How to respond to the crisis of COVID-19 and post-COVID-19 will determine the future of the world and Korea.

• 반도체디스플레이기술학회지
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• 제6권2호
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• pp.35-40
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• 2007

An integrated material removal model considering thermal, chemical and contact mechanical effects in CMP process is proposed. These effects are highly coupled together in the current modeling effort. The contact mechanics is employed in the model incorporated with the heat transfer and chemical reaction mechanisms. The mechanical abrasion actions happening due to the mechanical contacts between the wafer and abrasive particles in the slurry and between the wafer and pad asperities cause friction and consequently generate heats, which mainly acts as the heat source accelerating chemical reaction(s) between the wafer and slurry chemical(s). The proposed model may be a help in understanding multi-physical interactions in CMP process occurring among the wafer, pad and various consumables such as slurry.

• 한국산학기술학회논문지
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• 제10권3호
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• pp.560-566
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• 2009

저전력 RFID 시스템은 무선 주파수를 이용하여 물리적인 접촉 없이 사물에 대한 정보를 읽거나 기록하는 자동인식 기술이다. 이 시스템은 무선 주파수와 RFID 태그 사용으로 불법적인 위변조, 도청, 추적, 프라이버시 침해 등은 불가피하다 따라서 본 논문에서는 태그와 데이터베이스간에 해시 체인을 이용하여 키를 생성하는데 이를 통해 공격자는 위의 공격을 수행할 수 없다. 또한 계산 량을 줄이기 위해 해시 함수를 이용하여 효율성을 높였다.

• Current Applied Physics
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• 제18권12호
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• pp.1583-1591
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• 2018

We analysed perovskite $CH_3NH_3PbI_{3-x}Cl_x$ inverted planer structure solar cell with nickel oxide (NiO) and spiroMeOTAD as hole conductors. This structure is free from electron transport layer. The thickness is optimized for NiO and spiro-MeOTAD hole conducting materials and the devices do not exhibit any significant variation for both hole transport materials. The back metal contact work function is varied for NiO hole conductor and observed that Ni and Co metals may be suitable back contacts for efficient carrier dynamics. The solar photovoltaic response showed a linear decrease in efficiency with increasing temperature. The electron affinity and band gap of transparent conducting oxide and NiO layers are varied to understand their impact on conduction and valence band offsets. A range of suitable band gap and electron affinity values are found essential for efficient device performance.

• Current Photovoltaic Research
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• 제9권3호
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• pp.75-83
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• 2021

The tunnel oxide passivated contact (TOPCon) structure got more consideration for development of high performance solar cells by the introduction of a tunnel oxide layer between the substrate and poly-Si is best for attaining interface passivation. The quality of passivation of the tunnel oxide layer clearly depends on the bond of SiO in the tunnel oxide layer, which is affected by the subsequent annealing and the tunnel oxide layer was formed in the suboxide region (SiO, Si₂O, Si₂O₃) at the interface with the substrate. In the suboxide region, an oxygen-rich bond is formed as a result of subsequent annealing that also improves the quality of passivation. To control the surface morphology, annealing profile, and acceleration rate, an oxide tunnel junction structure with a passivation characteristic of 700 mV or more (V_oc) on a p-type wafer could achieved. The quality of passivation of samples subjected to RTP annealing at temperatures above 900℃ declined rapidly. To improve the quality of passivation of the tunnel oxide layer, the physical properties and thermal stability of the thin layer must be considered. TOPCon silicon solar cell has a boron diffused front emitter, a tunnel-SiO_x/n⁺-poly-Si/SiN_x:H structure at the rear side, and screen-printed electrodes on both sides. The saturation currents J_o of this structure on polished surface is 1.3 fA/cm² and for textured silicon surfaces is 3.7 fA/cm² before printing the silver contacts. After printing the Ag contacts, the J_o of this structure increases to 50.7 fA/cm² on textured silicon surfaces, which is still manageably less for metal contacts. This structure was applied to TOPCon solar cells, resulting in a median efficiency of 23.91%, and a highest efficiency of 24.58%, independently. The conversion efficiency of interdigitated back-contact solar cells has reached up to 26% by enhancing the optoelectrical properties for both-sides-contacted of the cells.