• Korean Journal of Materials Research
• /
• v.19 no.2
• /
• pp.61-67
• /
• 2009

Electrolessly deposited Co (Re,P) was investigated as a possible capping layer for Cu wires. 50 nm Co (Re,P) films were deposited on Cu/Ti-coated silicon wafers which acted as a catalytic seed and an adhesion layer, respectively. To obtain the optimized bath composition, electroless deposition was studied through an electrochemical approach via a linear sweep voltammetry analysis. The results of using this method showed that the best deposition conditions were a $CoSO_4$ concentration of 0.082 mol/l, a solution pH of 9, a $KReO_4$ concentration of 0.0003 mol/l and sodium hypophosphite concentration of 0.1 mol/L at $80^{\circ}C$. The thermal stability of the Co (Re,P) layer as a barrier preventing Cu was evaluated using Auger electron spectroscopy and a Scanning calorimeter. The measurement results showed that Re impurities stabilized the h.c.p. phase up to $550^{\circ}C$ and that the Co (Re,P) film efficiently blocked Cu diffusion under an annealing temperature of $400^{\circ}C$ for 1hr. The good barrier properties that were observed can be explained by the nano-sized grains along with the blocking effect of the impurities at the fast diffusion path of the grain boundaries. The transformation temperature from the amorphous to crystal structure is increased by doping the Re.

• Health Policy and Management
• /
• v.16 no.3
• /
• pp.86-106
• /
• 2006

The purpose of the study is 1) to explore clinic and hospital CEOs' satisfaction and expectation level on the affiliation with the larger size teaching hospitals, 2) to find the factors influencing the satisfaction and expectation level on the affiliation with the large hospitals. Data for analysis was collected to use self-administrative structured questionnaire on 335 CEOs of small or middle sized clinics and hospitals affiliated with large sized teaching hospitals located in Seoul and Kyung Ki Province. For the study, the researchers develop the constructs for questions on the satisfaction and the expectation of the affiliation, the attitude, knowledge on the affiliation, previous relationship of the affiliation, and selection guideline of the affiliation with exploratory factor analysis and reliability test. Through the confirmative factor analysis using AMOS 4, the researchers develop constructs based on exact relationship between constructs and questions. CEOs' expressive and unexpressive satisfaction level are 2.54 of 5 point(38.5 of 100) and 2.78 of 5 point(44.5 of 100), and the expressive and unexpressive expectation level are 2.77 of 5 point(44.3) and 3.16 of 5 point(54.0). These levels are relatively row for importance of affiliation. Expectation levels do not influence satisfaction levels. Attitude of affiliation influences expressive expectation and unexpressive satisfaction, reason for affiliation unexpressive satisfaction, and previous relationship to affiliated hospitals influence both of expressive and unexpressive satisfaction. The expressive expectation level and the expressive satisfaction level influence unexpressive expectation and unexpressive satisfaction, respectively. There is cognitive dissonance between expectation and satisfaction, therefore numbers of affiliation might be smaller or weaker in the future than present time. Many CEOs feel environmental press such as competition and the press of health insurance, but they might not think affiliation is best solution. Therefore, large hospitals try to give affiliated clinics and hospitals practical benefits to increase satisfaction and expectation levels, and they need to new affiliation form such as joint venture and joint ownership. The expectation and the satisfaction level was influenced by CEOs' gender, type of health service facilities, distances between the affiliated facility and the large mother hospital, and reason for affiliation.

• The KIPS Transactions:PartC
• /
• v.13C no.5 s.108
• /
• pp.613-620
• /
• 2006

From both techlical and economic viewpoints, DiffServ IP QoS architecture is accepted as a more practical solution because of the complexity Problem of the other IntServ architecture. In this paper, we propose several models to support DiffServ QoS in DSL broadband access networks and discuss about migration path from current best-effort DSL networks to DiffServ-enabled ones. Since DSL networks are recently and widely deployed in the world amount ot new investment, compatibility with existing QoS-unaware DSL systems, and compatibility with existing charging systems as well as effective support of various QoS services must be carefully considered when we design DiffServ QoS support models in DSL networks. The DiffServ models proposed in this paper are divided into static DiffServ models and dynamic DiffServ models which are near-term solutions and long-term solutions repecitively. The static DiffServ models include Flat DiffServ which suworts per-subscriber DiffServ QoS and Structured DiffServ which supports per-subscriber and per-service DiffServ QoS. And the dynamic DiffServ models include Direct DiffServ for P2P(Peer to Peer) applications and Indirect DiffServ for ASP(Application Service Provider) applications.

• Journal of Korea Multimedia Society
• /
• v.14 no.11
• /
• pp.1438-1449
• /
• 2011

UWSNs(Underwater Wireless Sensor Networks) need effective modeling fitted to the customized type of application and its covering area. In particular it requires an energy efficient data aggregation method for such customized application. In this paper, we envisage the application oriented model for monitoring the pollution or intrusion detection over a given underwater area. The suggested model is based on the honeycomb array of hexagonal prisms. In this model, the purpose of data aggregation is that the head node of each layer(cluster) receives just one event data arrived firstly and transfer this and its position data to the base station effectively in the manner of energy efficiency and simplicity without duplication. Here if we apply the existent data aggregation methods to this kind of application, the result is far from energy efficiency due to the complexity of the data aggregation process based on the shortest path or multicast tree. In this paper we propose three energy efficient and simple data aggregation methods in the domain of cluster and three in the domain of inter-cluster respectively. Based on the comparative performance analysis of the possible combination pairs in the two domains, we derive the best energy efficient data aggregation method for the suggested application.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.47 no.2
• /
• pp.21-28
• /
• 2010

This paper reports an experimental result on optimizing dissimilarity-based classification(DBC) by simultaneously using a dynamic time warping(DTW) and a multiple fusion strategy(MFS). DBC is a way of defining classifiers among classes; they are not based on the feature measurements of individual samples, but rather on a suitable dissimilarity measure among the samples. In DTW, the dissimilarity is measured in two steps: first, we adjust the object samples by finding the best warping path with a correlation coefficient-based DTW technique. We then compute the dissimilarity distance between the adjusted objects with conventional measures. In MFS, fusion strategies are repeatedly used in generating dissimilarity matrices as well as in designing classifiers: we first combine the dissimilarity matrices obtained with the DTW technique to a new matrix. After training some base classifiers in the new matrix, we again combine the results of the base classifiers. Our experimental results for well-known benchmark databases demonstrate that the proposed mechanism achieves further improved results in terms of classification accuracy compared with the previous approaches. From this consideration, the method could also be applied to other high-dimensional tasks, such as multimedia information retrieval.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.14 no.4
• /
• pp.438-444
• /
• 2004

The intelligent robots that will be needed in the near future are human-friendly robots that are able to coexist with humans and support humans effectively. To realize this, robots need to recognize their position and posture in known environment as well as unknown environment. Moreover, it is necessary for their localization to occur naturally. It is desirable for a robot to estimate of his position by solving uncertainty for mobile robot navigation, as one of the best important problems. In this paper, we describe a method for the localization of a mobile robot using image information of a moving object. This method combines the observed position from dead-reckoning sensors and the estimated position from the images captured by a fixed camera to localize a mobile robot. Using the a priori known path of a moving object in the world coordinates and a perspective camera model, we derive the geometric constraint equations which represent the relation between image frame coordinates for a moving object and the estimated robot's position. Since the equations are based or the estimated position, the measurement error may exist all the time. The proposed method utilizes the error between the observed and estimated image coordinates to localize the mobile robot. The Kalman filter scheme is applied for this method. its performance is verified by the computer simulation and the experiment.

• The Journal of the Korean dental association
• /
• v.49 no.11
• /
• pp.688-703
• /
• 2011

Park Myoung Jin (1903-1957) was a respectable leader who disseminated dental medical education to make our path as the leading dental medical education developing a new global history of dental medicine. Dr. Park was born in Seoul on 3 July 1903. He graduated Kyongseong dental medical school and studied at the pharmacology department achieving his M.D. In 1938, as the president representing the Hanseong dentists association equivalent to the Japanese dentists association, Dr. Park participated in various events. After liberation, Dr. Park tried his best to achieve Korean dental medical education as the pursuit of ideal ego with self-centered ego. He reorganized the Kyongseong dental medical school and incorporated it to the Seoul National University dental college. Even during the Korea war, Dr. Park still sincerely carried out his duties as the director of the Seoul National University dental medical college by recruiting university entrants and turned out graduates. In 1954, Dr. Park as the director of the Seoul National University dental medical college, he frontiered an opportunity to adapt the American dental medicine by sending school staffs to study overseas. On 25 June 1954, Dr. Park received 25 years of meritorius service award presented by Seoul National University Dental Medical College. Further, on 6 Aril 1954, Dr. Park became a member of an academic research committee. In April 1946, Dr. Park was elected as the president of the Chosun Dentists Association(Korean Dental Association). On 19 May 1947, Dr. Park was also appointed as the director of the Korea dental medicine association leading the general meetings and academic conferences from 2nd through the 8th sessions. On 30 November 1954, as the president of the Korea dental medicine association, Dr. Park also published the Korea dental association publications. In 1957, Dr. Park donated the school housing for the principle of the Kyongseong dental medical school establishing the basis for the Korea dentists association center. Dr. Park also participated in establishment of the oral hygiene campaigne, dental administration policy, organization of the specialized subject delegation board members and the dental materials association. On 10 December 1955, we can recognize Dr. Park's respective historical consciousness through his declaration 'history is a true record of historical traces of a national'. Dr. Park was a living witness of the Korean dental industry. Especially, he stated that the origin of the Korean dentists association was in the Hanseong dentists association. Dr. Park overcame the pressure and indignity during the Japanese colonization. The joy of liberation did not last long since he also had to experience the fraticidal tragedy of the Korea war. Dr. Park was a professional dental specialist and a leader researching dental medicine. He was a great leader who understood the dental medicine and dedicated for the dentist association and dental medicine association with compassion for the nation and national as a Korean.

• Journal of the Microelectronics and Packaging Society
• /
• v.17 no.2
• /
• pp.41-47
• /
• 2010

The effect of PCB and BGA pad designs was investigated on the mechanical property of Pb-free solder joints. The mechanical property of solder joint was tested by three different test methods of drop impact tests, bending impact test, and high speed shear test. Two kinds of pad design such as NSMD (Non-Solder Mask Defined) and SMD (Solder Mask Defined) were applied with the OSP finished Pb-free solder (Sn-3.0Ag-0.5Cu, Sn-1.2Ag-0.5Cu). in the drop impact test and bending impact test, the characterized lifetime showed the same tendency, and SMD design showed better mechanical property of solder joint than NSMD regardless of test method, which was due to the different crack path. The fracture crack on SMD pad was propagated along the intermetallic compound (IMC) layer of solder joint, while the fracture crack on NSMD pad propagated through upper edge of land which shields pattern. In the high speed shear test, pad lift occurred on the solder joint of NSMD. SMD/SMD combination of pad design consequently illustrated the best mechanical property of BGA/PCB solder joint, followed by SMD/NSMD, NSMD/SMD, and NSMD/NSMD.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.20 no.3
• /
• pp.71-76
• /
• 2014

Master packaging system is a technology combining primary and secondary packaging to preserve the fresh produce in the supply chain. Master packaging system with tailor-designed gas transfer and $CO_2$ absorber of $Ca(OH)_2$ was applied to fresh shiitake mushroom in its supply from farm to retail store. The temperature, humidity and package atmosphere were monitored through the distribution and/or storage until the packages were opened to measure the mushroom quality. Conventional perforated individual packages without secondary master pack were prepared and travelled the same path for comparison purpose. While high temperature history was observed in some initial period of actual practice of the mushroom transportation and storage unexpectedly, the package atmosphere around the produce in the master packaging system was maintained at modified atmosphere consisting of $O_2$ concentration of 0.4 to 4.2% and $CO_2$ concentration of 0.7 to 1.7%, which is known to be beneficial for the mushroom preservation. While curing the mushrooms with precooled drying was effective for quality preservation, positive effect of master packaging system could be apparent for the uncured mushroom. Harmonized combination of curing treatment, master packaging system and temperature management was suggested for the best quality preservation of the fresh shiitake mushroom.

• Journal of KIISE:Computing Practices and Letters
• /
• v.11 no.1
• /
• pp.15-25
• /
• 2005

Embedded systems have a set of tasks to execute. These tasks can be implemented either on application specific hardware or as software running on a specific processor. The design of an embedded system involves the selection of hardware software resources, Partition of tasks into hardware and software, and performance evaluation. An accurate estimation of execution time for extreme cases (best and worst case) is important for hardware/software codesign. A tighter estimation of the execution time bound nay allow the use of a slower processor to execute the code and may help lower the system cost. In this paper, we consider an ARM-based embedded system and developed a tool to estimate the tight boundary of execution time of a task with loop bounds and any additional program path information. The tool we developed is based on an exiting timing analysis tool named 'Cinderella' which currently supports i960 and m68k architectures. We add a module to handle ARM ELF object file, which extracts control flow and debugging information, and a module to handle ARM instruction set so that the new tool can support ARM processor. We validate the tool by comparing the estimated bound of execution time with the run-time execution time measured by ARMulator for a selected bechmark programs.