• Fire Science and Engineering
• /
• v.24 no.5
• /
• pp.136-141
• /
• 2010

The purpose of this study is to examine the structure and heat generation mechanism of low voltage switches used to turn on or off the power supply to an indoor lighting system and investigate how the fixtures and movable contacts of the switches are damaged depending on the types of energy sources in order to secure the judgment base for expected PL disputes. Based on the Korean Standard (KS) testing method for incombustibility, this study applied a general flame to the switch. In addition, current was supplied to the switch using the PCITS (Primary Current Injection Test System). The ambient temperature and humidity were maintained at $22{\pm}2^{\circ}C$ and 40~60% respectively while performing the test. It is thought that the switch generated heat due to a defective connection of the wire and clip, insulation deterioration and defective contact of the movable contact, etc. The surface of the switch damaged by the general flame was uniformly carbonized. When the flame source was removed, the fire on the switch was extinguished naturally. From the result obtained by disassembling the switch carbonized by the general flame, it could be seen that fixtures and movable contacts remained in comparatively good shape but the enclosure, clip support, movable contact, indicating lamp, etc. showed carbonization and discoloration. In the case of the switch damaged by overcurrent, the clip connecting the wires, clip support, etc. showed almost no trace of damage, but the fixtures, movable contact, indicating lamp, etc. were severely carbonized. That is, the sections with high contact resistance were intensively damaged and showed a damage pattern indicating that carbonization progressed from the inside to the outside. Therefore, it is possible to judge the initial energy source by analyzing the characteristics of the carbonization pattern and the metal fixtures of damaged switches.

• Journal of The Korean Astronomical Society
• /
• v.50 no.6
• /
• pp.167-178
• /
• 2017

We present a study of the inexplicit connection between radio jet activity and ${\gamma}$-ray emission of BL Lacertae (BL Lac; 2200+420). We analyze the long-term millimeter activity of BL Lac via interferometric observations with the Korean VLBI Network (KVN) obtained at 22, 43, 86, and 129 GHz simultaneously over three years (from January 2013 to March 2016); during this time, two ${\gamma}$-ray outbursts (in November 2013 and March 2015) can be seen in ${\gamma}$-ray light curves obtained from Fermi observations. The KVN radio core is optically thick at least up to 86 GHz; there is indication that it might be optically thin at higher frequencies. To first order, the radio light curves decay exponentially over the time span covered by our observations, with decay timescales of $411{\pm}85$ days, $352{\pm}79$ days, $310{\pm}57$ days, and $283{\pm}55$ days at 22, 43, 86, and 129 GHz, respectively. Assuming synchrotron cooling, a cooling time of around one year is consistent with magnetic field strengths $B{\sim}2{\mu}T$ and electron Lorentz factors ${\gamma}$ ~ 10 000. Taking into account that our formal measurement errors include intrinsic variability and thus over-estimate the statistical uncertainties, we find that the decay timescale ${\tau}$ scales with frequency ${\nu}$ like ${\tau}{\propto}{\nu}^{-0.2}$. This relation is much shallower than the one expected from opacity effects (core shift), but in agreement with the (sub-)mm radio core being a standing recollimation shock. We do not find convincing radio flux counterparts to the ${\gamma}$-ray outbursts. The spectral evolution is consistent with the 'generalized shock model' of Valtaoja et al. (1992). A temporary increase in the core opacity and the emergence of a knot around the time of the second ${\gamma}$-ray event indicate that this ${\gamma}$-ray outburst might be an 'orphan' flare powered by the 'ring of fire' mechanism.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.10 no.4
• /
• pp.659-666
• /
• 2006

Servo-motors are used as key components of automated system by performing precise motion control as accurate positioning and accurate speed regulation in response to the commands from computers and sensors. Especially, the linear brushless servo-motors have numerous advantages over the rotary servo motors which have connection with the friction induced transfer mechanism such as ball screws, timing belts, rack/pinion. This paper proposes an estimation method of unknown motor system parameters using the informations from the sinusoidal driving type linear brushless DC motor dynamics and outputs. The estimated parameters can be used to tune the controller gain and a disturbance observer. In order to meet this purpose high performance Digital Signal Processor, TMS320F240, designed originally for implementation of a Field Oriented Control(FOC) technology is adopted as a controller of the liner BLDC servo motor. Having A/D converters, PWM generators, rich I/O port internally, this servo motor application specific DSP play an important role in servo motor controller. This linear BLDC servo motor system also contains IPM(Intelligent Power Module) driver and hail sensor type current sensor module, photocoupler module for isolation of gate signals and fault signals.

• The KIPS Transactions:PartD
• /
• v.9D no.6
• /
• pp.1105-1112
• /
• 2002

Nowadays the information exchange based on XML such as B2B electronic commerce is spreading. Therefore a systematic and stable management mechanism for storing the exchanged information is needed. For this goal there are many research activities for concerning the connection between XML application and relational databases. But because XML data has hierarchical structure and relational databases can store only flat-structured data, we need to make a conversion rule which changes the hierarchical architecture to a 2-dimensional format. Accordingly the modeling methodology for storing such structured information in relational databases is needed. In order to build good quality application systems, modeling is an important first step. In 1997, the OMG adopted the UML as its standard modeling language. Since industry has warmly embraced UML, its popularity should become more important in the future. So a design methodology based on UML is needed to develop efficient XML applications. In this paper, we propose a unified design methodology for XML applications based on relational database using UML. To reach these goals, first we introduce a XML modeling methodology to design W3C XML schema using UML and second we propose data modeling methodology for relational database schema to store XML data efficiently in relational databases.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.20 no.3
• /
• pp.651-656
• /
• 2006

Activation of $NF-{\kappa}B$ is known to be a trigger of various cellular disorders including inflammatory and autoimmune diseases such as rheumatoid arthritis. Numerous approaches are ongoing within laboratories to identify potential therapeutic agents which inhibit the $NF-{\kappa}B$ activation. In this study, we have tested the inhibitory effects of five traditional medicines on the activation of $NF-{\kappa}B$ by NIK. Among three medicines which exhibited inhibitory effect on the expression of $NF-{\kappa}B$ repoter plasmid, we investigated further the inhibitory mechanism of Dichroa febrifuga in connection with IKKY activity. Wild type $IKK{\gamma}$ inhibited the $NF-{\kappa}B$ activation by NIK but the C-terminal deletion mutant of IKKY did not show the inhibitory effect, indicating that the C-terminal leucine zipper domain of $NF-{\kappa}B$ is important for the inhibition of $NF-{\kappa}B$ activation. The water extract of Dichroa febrifuga(DFE) also strongly inhibited the $NF-{\kappa}B$ activation by NIK. The inhibitory activity of DFE appeared to be independent of the expression of $IKK{\gamma}$, suggesting that the pathways of inhibition by Dichroa febrifuga and $IKK{\gamma}$ are different. Our results suggest that Dichroa febrifuga can be used as a medicine for inhibition of the $NF-{\kappa}B$ activation in a wide range of cells without relation to the expression of $IKK{\gamma}$.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.1
• /
• pp.81-89
• /
• 2018

Austenitic stainless steels have excellent corrosion resistance, durability and fire resistance. Especially, since STS304L among austenitic types is a low-carbon variation of STS304 and has excellent intergranular corrosion resistance, it can often be used under the welded condition without heat treatment after field welding. This paper investigated ultimate behaviors such as ultimate strength and weld metal fracture mechanism of STS304L fillet-welded connections with TIG(tungsten inert gas) welding through test results. Main variables of specimens are weld length and welding direction against loading. Fracture of specimens are classified into three modes(tensile fracture, shear fracture and block shear fracture). Ultimate strengths were compared according to the welding direction and weld length and TFW series with transverse fillet weld had the highest strength compared with other types(LFW series with longitudinal fillet weld and FW series with all round weld). It is known that current design specifications such as KBC 2016 and AISC2010 underestimated the strength of TFW and LFW specimens and provided unconservative estimates for FW specimens. Finally, strength equations were proposed considering material properties of STS 304L material.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.39 no.1
• /
• pp.20-33
• /
• 2002

Usage of ATM AAL2 packets becomes dominant to increase transmission efficiency of voice traffic in the backbone network. In case of voice service that uses AAL2 mechanism, if resources of network are enough, connection of new call is accepted. However, due to packets generated by the new call, transmission delay of packets from old calls can increase sharply. To control this behavior, in this paper we present an AAL2 buffer management scheme that allocates a virtual buffer to each call and after calculating its propagation delay variation(PDV), decides to drop packets coming from each call according to the PDV value. We show that this packet dropping algorithm can effectively prevent abrupt QoS degradation of old calls. To do this, we analyze AAL2 packet composition process to find a critical factor in the process that influences the end-to-end delay behavior and model the process by K-policy M/D/1 queueing system and MIN(K, Tc)-policy M/D/1 queueing system. From the mathematical model, we derive the probability generating function of AAL2 packets in the buffer and mean waiting time of packets in the AAL2 buffer. Analytical results show that the AAL2 packet dropping algorithm can provide stable AAL2 packetization delay and ATM cell generation time even if the number of voice sources increases dramatically. Finally we compare the analytical result to simulation data obtained by using the COMNET Ⅲ package.

• Journal of Gastric Cancer
• /
• v.1 no.2
• /
• pp.92-99
• /
• 2001

Purpose: E-cadherin is an adhesion molecule essential for tight connection between cells, forming the cadherin/catenin complex. Truncated $\beta$-catenin disrupts the interaction between E-cadherin and $\alpha$-catenin, leading to the loss of intercellular adhesion. Met protein, the hepatocyte growth factor receptor, plays important roles in signal transduction. We investigated the relationships between the expressions of E-cadherin, $\beta$-catenin, and c-met protein and the clinicopathological and prognostic parameters in gastric adenocarcinomas. Materials and Methods: The patterns of E-cadherin, $\beta$-catenin, and c-met protein expression were studied using immunohistochemistry in formalin-fixed, paraffin-embedded archival tissues from 76 surgically resected gastric adenocarcinomas. Results: Increased expressions of E-cadherin, $\beta$-catenin, and c-met were more significantly correlated in early gastric cancers (EGC) than in advanced gastric cancers (AGC) (P=0.002, P=0.003 and P=0.026). The positive immunoreactivities of all three markers were markedly lower in signet ring-cell type and poorly differentiated type lesions than in intestinal-type lesions. Decreased expression of the $\beta$-catenin protein correlated well with increased tumor invasion depth (P=0.039), and increased lymph node metastasis correlated well with reduced expression of c-met (P=0.046). Conclusion: In gastric cancers, reduced expressions of the E-cadherin, $\beta$-catenin, and c-met proteins may play some role in poorer tumor differentiation, deeper tumor invasion, and increased lymph node metastasis. Also, the c-met gene is thought to play a specific role in the mechanism of the yet unknown catenin action.

• KIPS Transactions on Software and Data Engineering
• /
• v.2 no.8
• /
• pp.517-526
• /
• 2013

When developing an android mobile application the androids intent is used as a mechanism to send messages between local equipment of androids application inner part and other applications. But the androids intent does not support sending messages via each android products intent. If there is a way to support each androids equipments to send messages, it will be easier to make non-stopping services. Non-stopping service is used when the user is using the android to do word or searching services and suddenly changes to a different android product but still maintains the progress what was currently being done without waiting the programs to be loaded. It is possible to send messages to each android products by using the socket, but the connection must be maintained stably which is the weak point. In this paper, I am suggesting a BRIF(Broadcasting Remote Intent Framework) framework to send messages to different android products. BRIF is a framework that uses the Googles C2DM service which services asynchronous transmissions to different android products. This is organized with the C2DM server, RemoteContext Api, web server and RISP(Remote Intent Service Provider) which is will be easy to be used for the developers since there are no big changes for coding compared to the intent code.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.3 no.1
• /
• pp.57-72
• /
• 2008

Serve and do so that graft together specialists' view application field of computer and developmental disability diagnosis estimation data to construct developmental disability diagnosis estimation system in this Paper and constructed developmental disability diagnosis estimation system. Developmental disability diagnosis estimation must supply information of specification area that specialists are having continuously. Developmental disability diagnosis estimation specialist system need multimedia data processing that is specialized little more for developmental disability classification diagnosis and decision-making and is atomized for this. Characteristic of developmental disability diagnosis estimation system that study in this paper can supply quick feedback about result, and can reduce mistake on recording and calculation as well as can shorten examination's enforcement time, and background of training is efficient system fairly in terms of nonprofessional who is not many can use easily. But, as well as when multimedia information that is essential data of system construction for developmental disability diagnosis estimation is having various kinds attribute and a person must achieve description about all developmental disability diagnosis estimation informations, great amount of work done is accompanied, technology about equal data can become different according to management. Because of these problems, applied search technology of contents base (Content-based) that search connection information by contents of edit target data for developmental disability diagnosis estimation data processing multimedia data processing technical development. In the meantime, typical access way for conversation style data processing to support fast image search, after draw special quality of data by N-dimension vector, store to database regarding this as value of N dimension and used data structure of Tree techniques to use index structure that search relevant data based on this costs. But, these are not coincided correctly in purpose of developmental disability diagnosis estimation because is developed focusing in application field that use data of low dimension such as original space DataBase or geography information system. Therefore, studied save structure and index mechanism of new way that support fast search to search bulky good physician data.