• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.546-546
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• 2008

Copper (Cu) Chemical mechanical polishing (CMP) has been an essential process for Cu wifing of DRAM and NAND flash memory beyond 45nm. Copper has been employed as ideal material for interconnect and metal line due to the low resistivity and high resistant to electro-migration. Damascene process is currently used in conjunction with CMP in the fabrication of multi-level copper interconnects for advanced logic and memory devices. Cu CMP involves removal of material by the combination of chemical and mechanical action. Chemicals in slurry aid in material removal by modifying the surface film while abrasion between the particles, pad, and the modified film facilitates mechanical removal. In our research, we emphasized on the role of chemical effect of slurry on Cu CMP, especially on the effect of amine functional group on removal rate selectivity between Cu and Tantalum-nitride (TaN) film. We investigated the two different kinds of complexing agent both with amine functional group. On the one hand, Polyacrylamide as a polymer affected the stability of abrasive, viscosity of slurry and the corrosion current of copper film especially at high concentration. At higher concentration, the aggregation of abrasive particles was suppressed by the steric effect of PAM, thus showed higher fraction of small particle distribution. It also showed a fluctuation behavior of the viscosity of slurry at high shear rate due to transformation of polymer chain. Also, because of forming thick passivation layer on the surface of Cu film, the diffusion of oxidant to the Cu surface was inhibited; therefore, the corrosion current with 0.7wt% PAM was smaller than that without PAM. the polishing rate of Cu film slightly increased up to 0.3wt%, then decreased with increasing of PAM concentration. On the contrary, the polishing rate of TaN film was strongly suppressed and saturated with increasing of PAM concentration at 0.3wt%. We also studied the electrostatic interaction between abrasive particle and Cu/TaN film with different PAM concentration. On the other hand, amino-methyl-propanol (AMP) as a single molecule does not affect the stability, rheological and corrosion behavior of the slurry as the polymer PAM. The polishing behavior of TaN film and selectivity with AMP appeared the similar trend to the slurry with PAM. The polishing behavior of Cu film with AMP, however, was quite different with that of PAM. We assume this difference was originated from different compactness of surface passivation layer on the Cu film under the same concentration due to the different molecular weight of PAM and AMP.

• Korean Journal of Agricultural Science
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• v.28 no.1
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• pp.8-17
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• 2001

This study was carried out to obtain a basic intonation for the development of a new com hybird with tillers. Materials used in this study were 20 lines having three to four tillers per plant including the PI213749 U.S. line with non-tillers. These 20 lines were compared for the botanical characteristics and genetic distances were measured using RAPD analysis. Flowering date of the K15 was very earlier, while the K07 was very late in flowering date. Stem height and ear height were similar except for K04 and the K15. K06, K13 and K19 lines were appeared to be resistant to lodging due to decreased ear height. Number of tillers per plant of lines used were shown three to five on average. K09 showed the highest kernel yield, while the K08 was low. Among characteristics measured tiller per plant and flowering dates, and silking dates showed a positive correlation, while 100 kernels weight, flowering date and ear height were shown a negative with tillers per plant. A total of 17 bands by RAPD analysis using four per primer were appeared and these lines were classified into three groups, especially the third group could be classified into of four sub-groups.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.4
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• pp.403-415
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• 2014

Recently, the temperature rise in the summer due to climate change, power usage is increasing rapidly. As a result, power generation facilities have been newly completed and the need for ultra-high-voltage transmission line for power transmission of electricity to the urban area has increased. The mechanized tunnelling method using a shield TBM have an advantage that it can minimize vibrations transmitted to the ground and ground subsidence as compared with the conventional tunnelling method. Despite the popularity of shield TBM for cable tunnel construction, study on the mechanical behavior of cable tunnel driven by shield TBM is insufficient. Thus, in this study, the effect of fractured zone ahead of tunnel face on the mechanical behavior of the shield TBM cable tunnel is investigated. In addition, it is intended to compare the behavior characteristics of the fractured zone with continuous model and applying the interface elements. Tunnelling with shield TBM is simulated using 3D FEM. According to the change of the direction and magnitude of the fractured zone, Sectional forces such as axial force, shear force and bending moment are monitored and vertical displacement at the ground surface is measured. Based on the stability analysis with the results obtained from the numerical analysis, it is possible to predict fractured zone ahead of the shield TBM and ensure the stability of the tunnel structure.

• Journal of Korean Academy of Nursing
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• v.9 no.2
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• pp.49-61
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• 1979

A review of this literature and discussions reveal a development of ideas concerning the elements of nursing models. The elements of a nursing model are the nurses view of the human being, nursing's goal, and nursing activities. It has long been recognized that human beings, at one time or another, require nursing care. Varieties of literature were reviewed in regard to the human being as recipient of nursing care through the theory development in nursing. Florence Nightingale initiated the modern era of nursing and described more clearly man as the recipient of nursing care. She looked at man as responding to the laws of nature whether the person was healthy or sick. Henderson added to Nightingale's concept of man , the recipient of nursing care by emphasizing that man is a whole, complete, and independent being. Her view is further specified by her enumeration of the activities the human being must perform. Johnson has developed a very comprehensive view of man as the recipient of nursing care. Man is a behavioral system which has a tendency to achieve and maintain stability in patterns of functioning. Like Nightingale, Johnson sees that similar patterns occur in both health and illness. Johnson postulates that the whole behavioral system of the human is composed of eight sub-systems: affiliative, achievement, aggressive, dependency, eliminative, ingestive, restorative, sexual. Roger's main contribution to the development of nursing models was her emphasis upon unitary man. She pointed out that man is a unified whole, possessing his own integrity and manifesting characteristics that“are more than and different from the sum of his parts.”Rogers focuses on the life processes of the human and points out that these processes have the following characteristics. Wholeness, openness, unidirectionality, pattern and organization, sentence, and thought. According to Roy, man is a biopsychosocial being in constant interaction with a changing environment. To cope with this changing environment, man has certain innate and acquired mechanisms. Man's ability to respond positively or to adapt, depends upon the degree of the change taking place and the state of the person coping with the change. When she analyzes man as an adaptive organism she further describes man as being composed of four adaptive modes: physiological needs, self-concept, role function, and interdependence. Based on the literary review through the theory development in nursing, general approach by a unified nursing model to a view of the recipient of nursing care may be stated as follows: Man is a unified whole composed of subsystems with a flexible and normal line of defense; his internal regulating mechanisms help him to cope with a changing environment; he functions by the principles of homeodynamics.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.71-84
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• 2009

The communication between the center system and the local controller in the Traffic Signal Controller Specification has been specified by a communication line for the exclusive use and the analog modem serial protocol. Therefore, it can't be adapted in the ITS communication network of the TCP/IP protocol being constructed in the local city. The international and domestic ITS device's communication specification has adapted the DATEX-ASN data exchange technique based on the ethernet communication network. So, this study was performed by the purpose of developing the application communication protocol's standard draft based on the TCP/IP communication protocol for the traffic signal controller, to be able to constitute the traffic signal control system in the ITS communication network. The communication format for 23 items of control, status, and database request etc. which are specified in the standard traffic signal controller was developed by appling the DATEX-ASN data interface procedure and structure which are KS ISO X 14827 Part1, 2, ISO/ DIS 15784 Part-3. To test the developed protocol, the application program for the communication items was developed and according to the test result, the encoding and the decoding transection for all communication items was possible.

• International Journal of Railway
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• v.2 no.3
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• pp.124-126
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• 2009

Energy savings can be achieved with optimum energy consumptions, brake energy regeneration, efficient energy storage (onboard, line side), and primarily with light weight vehicles. Over the last few years, the rolling stock industry has experienced a marked increase in eco-awareness and needs for lower life cycle energy consumption costs. For rolling stock vehicle designers and engineers, weight has always been a critical design parameter. It is often specified directly or indirectly as contractual requirements. These requirements are usually expressed in terms of specified axle load limits, braking deceleration levels and/or demands for optimum energy consumptions. The contractual requirements for lower weights are becoming increasingly more stringent. Light weight vehicles with optimized strength to weight ratios are achievable through proven design processes. The primary driving processes consist of: $\bullet$ material selection to best contribute to the intended functionality and performance $\bullet$ design and design optimization to secure the intended functionality and performance $\bullet$ weight control processes to deliver the intended functionality and performance Aluminium has become the material of choice for modern light weight bodyshells. Steel sub-structures and in particular high strength steels are also used where high strength - high elongation characteristics out way the use of aluminium. With the improved characteristics and responses of composites against tire and smoke, small and large composite materials made components are also found in greater quantities in today's railway vehicles. Full scale hybrid composite rolling stock vehicles are being developed and tested. While an "overdesigned" bodyshell may be deemed as acceptable from a structural point of view, it can, in reality, be a weight saving missed opportunity. The conventional pass/fail structural criteria and existing passenger payload definitions promote conservative designs but they do not necessarily imply optimum lightweight designs. The weight to strength design optimization should be a fundamental design driving factor rather than a feeble post design activity. It should be more than a belated attempt to mitigate against contractual weight penalties. The weight control process must be rigorous, responsible, with achievable goals and above all must be integral to the design process. It should not be a mere tabulation of weights for the sole-purpose of predicting the axle loads and wheel balances compliance. The present paper explores and discusses the topics quoted above with a view to strengthen the recommendations and needs for the weight optimization by design approach as a pro-active design activity for the rolling stock industry at large.

• Journal of Navigation and Port Research
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• v.26 no.3
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• pp.289-294
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• 2002

The broadband high power 3-way combiner was designed and fabricated for the digital TV repeater. To achieve increase of the bandwidth and the high power capability, Wilkinson type power divider was adopted in our research. First of all, Wilkinson type power divider of equal-split and unequal-split were combined, and the characteristics of the four port in-phase power combiner was simulated for each thickness of dielectric substrates. As the results of simulation, the power combiner fabricated by using dielectric substrate of 120 mil-thickness has the characteristics as follows: insertion loss of less than -651 dB, reflection coefficient of less than -13 dB, isolation among the output ports of less than -15 dB, and pose difference among the output ports of smiler than 13$^{\circ}$. Therefore, this power combiner was possible to improve the limit of microstrip line width due to high impedance, the problem of power loss due to interaction between strip lines in a high power combiner and narrow bandwidth simultaneously. Furthermore, making broadband and high power could be achieved since the fabricated 3-way combiner has good characteristics of insertion loss, the reflection coefficient, separation between ports, and phase difference.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.229-229
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• 2010

With the scaling down of ultra large integrated circuits (ULSI) to the sub-50 nm technology node, the need for an ultra-thin, continuous and conformal diffusion barrier and Cu seed layer is increasing. However, diffusion barrier and Cu seed layer formation with a physical vapor deposition (PVD) method has become difficult as the technology node is reduced to 30 nm and beyond. Recent work on self-forming barrier processes using PVD Cu alloys have attracted great attention due to the capability of conformal ultra-thin barrier formation using a simple technique. However, as in the case of the conventional barrier and Cu seed layer, PVD of the Cu alloy seed layer will eventually encounter the difficulty in conformal deposition in narrow line trenches and via holes. Atomic layer deposition (ALD) has been known for its good step coverage and precise thickness control, and is a candidate technique for the formation of a thin conformal barrier layer and Cu seed layer. Conformal Cu-Mn seed layers were deposited by plasma enhanced atomic layer deposition (PEALD) at low temperature ($120^{\circ}C$), and the Mn content in the Cu-Mn alloys were controlled form 0 to approximately 10 atomic percent with various Mn precursor feeding times. Resistivity of the Cu-Mn alloy films decreased by annealing due to out-diffusion of Mn atoms. Out-diffused Mn atoms were segregated to the surface of the film and interface between a Cu-Mn alloy and $SiO_2$, resulting in self-formed $MnO_x$ and $MnSi_xO_y$, respectively. No inter-diffusion was observed between Cu and $SiO_2$ after annealing at $500^{\circ}C$ for 12 h, indicating an excellent diffusion barrier property of the $MnSi_xO_y$. The adhesion between Cu and $SiO_2$ was enhanced by the formation of $MnSi_xO_y$. Continuous and conductive Cu-Mn seed layers were deposited with PEALD into 32 nm $SiO_2$ trench, enabling a low temperature process, and the trench was perfectly filled using electrochemical plating (ECD) under conventional conditions. Thus, it is the resultant self-forming barrier process with PEALD Cu-Mn alloy film as a seed layer for plating Cu that has further potential to meet the requirement of the smaller than 30 nm node.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.2
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• pp.76-83
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• 2006

Epidemiological studies have indicated that the ubiquitous consumption of seaweeds is a protective factor against some types of cancer. Previous results showed that the administration of seaweed powder or extract reduced the incidence rate of chemically induced tumorigenesis using in vivo animal model. Recently, we reported that the extracts of Gloiopeltis furcata, a kind of Korean edible seaweed, caused he cell growth inhibition of various human cancer cell lines, among them methanol extract exhibited a relatively strong antiproliferative activity. However, the molecular mechanisms of this seaweed in malignant cells have been poorly studied until now. To elucidate this problem, we investigated the effects of methanol extract of G. furcata (MEGF) on the growth inhibition in several human cancer cell lines, and further we analyzed the effects of this extract were tested on the activity of apoptosis induction in human leukemic cells. The results demonstrated that MEGF treatment resulted in the morphological changes and the growth inhibition in a dose-dependent manner. Furthermore, MEGF potently suppresses the growth of human leukemic U937 cells by induction of apoptosis, which was associated with induction of cyclin-dependent kinase inhibitor p21(WAF1/CIP1) in a tumor suppressor p53-independent fashion and up-regulation of Fas/FasL system. Further studies will be needed to identify the active compounds that confer the anticancer activity of MEGF. Once such compounds are identified, the mechanisms by which they exert their effects can begin to be characterized.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.5
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• pp.77-89
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• 2008

The bikes are conflicted with the cars and the pedestrian at the intersection and the road with the bike crossing. To establish the bike signal at this section is one method to solve this conflict. According to the survey for the bike road status and the biker's characters which are crossing the road at the intersection, the bike crossing are established with beside the pedestrian crossing and most of the bikers are crossing the street by the pedestrian signal. Also, the bike queue which is waiting the signal change at the stop line was cleared before the closing the pedestrian signal. Considering the result of this survey, TOUCAN crossing signal type in England for bike signal at the place where the bike crossing are established with beside the pedestrian crossing, in which bike rider and pedestrian can cross by the pedestrian signal operation, is suggested. However, at the place where the bike crossing is apart from the pedestrian crossing, the bike signal which is connected to the vehicle signal is suggested. All these types of bike signals can be accepted for the present bike crossing equipments and the biker's characters and be adapted to the police standard traffic signal controller by adjusting the signal time only without any function change.