• Journal of Internet Computing and Services
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• v.23 no.6
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• pp.49-58
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• 2022

As military service members are fully permitted to use mobile phones for sickness after work, it is time to minimize the direct collection of personal information from telecommunication companies when opening mobile phones to secure the safety of military service personnel's personal information. Prior to introducing the use of mobile phones by soldiers after work, the Ministry of National Defense established a security control system such as blocking the mobile phone shooting function to prevent security accidents and concerns about some adverse functions such as illegal cyber gambling, game addiction, and viewing pornography. come. Mobile telecommunications companies entrust personal information processing tasks, such as opening mobile phones, to telecommunications agencies and carry out management and supervision, such as checking the status of personal information protection measures. When a military service member opens a mobile phone, a personal information management agency is newly established using the right to portability of personal information, and a system for requesting the transmission of personal information from the military service member is proposed.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.962-969
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• 2009

The market of building construction has been competitive in Hong Kong, perhaps as anywhere else in the world. The barrier to entry is low because there are relatively low requirements on the three factors of production - technology, manpower and finance. The prevailing building technology is traditional and labour-intensive. There is also not much need of capital because clients' periodic payments have been the main source of project finance. Further, capitalizing on trade sub-contracting, contractors have been able to keep their direct labour-force small and to transfer much of their business risk to the sub-contractors. Based on interviews to solicit the perception of a sample of building contractors on the particular issues of construction finance, we present the findings in this paper and discuss the various implications. We believe that the current practice of construction financing is both the cause and effect of the competition within, and the competitiveness of, the building construction sector in Hong Kong. We conclude that the building construction sector is "locked or stuck" in this "equilibrium" of traditional technology, reliance on clients' finance and exploitation of sub-contracting. In this "equilibrium" state, there is hardly any motivation for contractors to engage themselves in product or process innovation. Consequently, any talk of industry reform or innovation could only remain just that. We believe that this problem is not unique in Hong Kong. The building construction sector in many other developed and developing economies is posed with similar if not the same problems and constraints. We conclude that there has to be some "external forces" to bring this "equilibrium" state to a higher level "equilibrium" one where higher value-added building construction services are supplied and demanded. This is a state where building contractors possessing innovative technology, better financial and manpower resources could thrive to build better buildings with innovative building methods and processes.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.10
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• pp.154-160
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• 1996

The control of diamond turning is usually achieved through a laser-interferometer feedback of slide position. The limitation of this control scheme is that the feedback signal does not account for additional dynamics of the tool post and the material removal process. If the tool post is rigid and the material removal process is relatively static, then such a non-collocated position feedback control scheme may surfice. However, as the accuracy requirement gets tighter and desired surface cnotours become more complex, the need for a direct tool-tip sensing becomes inevitable. The physical constraints of the machining process prohibit any reasonable implementation of a tool-tip motion measurement. It is proposed that the measured force normal to the face of the workpiece can be filtered through an appropriate admittance transfer function to result in the estimated dapth of cut. This can be compared to the desired depth of cut to generate the adjustment control action in additn to position feedback control. In this work, the design methodology on the admittance model-based control with a conventional controller is presented. The recursive least-squares algorithm with forgetting factor is proposed to identify the parameters and update the cutting process in real time. The normal cutting forces are measured to identify the cutting dynamics in the real diamond turning process using the precision dynamoneter. Based on the parameter estimation of cutting dynamics and the admitance model-based nanodynamic control scheme, simulation results are shown.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.57.3-58
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• 2021

We performed three-dimensional Monte Carlo dust scattering radiative transfer simulations for FUV light to obtain dust scattered FUV images and compared them with the observed FUV image obtained by FIMS/SPEAR and GALEX. From this, we find the scattering properties of interstellar dust in our Galaxy and suggest the intensity of extragalactic background light (EBL) at FUV wavelength. The best-fit values of the scattering properties of interstellar dust are albedo = 0.38^-0.04_+0.04, g-factor = 0.55^-0.15_+0.10, and EBL = 138^-23₊₂₁ CU for the allsky which are consistent well with the Milky Way dust model of Draine and direct measurements of Gardner et al., respectively. At the high Galactic latitude of |b|>10°, the observation is well fitted with the model of lower albedo = 0.35^-0.04_+0.06 and g-factor = 0.50^-0.20_+0.15. On the contrary, the scattering properties of interstellar dust show higher albedo = 0.43^-0.02_+0.02 and g-factor = 0.65^-0.15_+0.05 near the Galactic plane of |b|<10°. In the present simulation, recent three-dimensional distribution maps of interstellar dust in our Galaxy, stellar distances in the catalog of GAIA DR2, and FUV fluxes and/or spectral types in the TD-1 and Hipparcos star catalogs were used.

• International Journal of Computer Science & Network Security
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• v.23 no.7
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• pp.1-8
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• 2023

An Orthogonal Frequency Division Multiplexing (OFDM) based wireless communication system has drawn wide attention for its high transmission rate and high spectrum efficiency in not only radio but also Underwater Acoustic (UWA) applications. Because of the narrow sub-carrier spacing of OFDM, orthogonality between sub-carriers is easily affected by Doppler effect caused by the movement of transmitter or receiver. Previously, Doppler compensation signal processing algorithm for Desired propagation path was proposed. However, other Doppler shifts caused by delayed Undesired signal arriving from different directions cannot be perfectly compensated. Then Receiver Bit Error Rate (BER) is degraded by Inter-Carrier-Interference (ICI) caused in the case of Multi-path Doppler channel. To mitigate the ICI effect, a modified Delay and Doppler Profiler (mDDP), which estimates not only attenuation, relative delay and Doppler shift but also sampling clock shift of each multi-path component, is proposed. Based on the outputs of mDDP, an ICI canceling multi-tap equalizer is also proposed. Computer simulated performances of one-tap equalizer with the conventional Time domain linear interpolated Channel Transfer Function (CTF) estimator, multi-tap equalizer based on mDDP are compared. According to the simulation results, BER improvement has been observed. Especially, in the condition of 16QAM modulation, transmitting vessel speed of 6m/s, two-path multipath channel with direct path and ocean surface reflection path; more than one order of magnitude BER reduction has been observed at CNR=30dB.

• Imaging Science in Dentistry
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• v.53 no.4
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• pp.271-281
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• 2023

Purpose: The objective of this scoping review was to investigate the applicability and performance of various convolutional neural network (CNN) models in tooth numbering on panoramic radiographs, achieved through classification, detection, and segmentation tasks. Materials and Methods: An online search was performed of the PubMed, Science Direct, and Scopus databases. Based on the selection process, 12 studies were included in this review. Results: Eleven studies utilized a CNN model for detection tasks, 5 for classification tasks, and 3 for segmentation tasks in the context of tooth numbering on panoramic radiographs. Most of these studies revealed high performance of various CNN models in automating tooth numbering. However, several studies also highlighted limitations of CNNs, such as the presence of false positives and false negatives in identifying decayed teeth, teeth with crown prosthetics, teeth adjacent to edentulous areas, dental implants, root remnants, wisdom teeth, and root canal-treated teeth. These limitations can be overcome by ensuring both the quality and quantity of datasets, as well as optimizing the CNN architecture. Conclusion: CNNs have demonstrated high performance in automated tooth numbering on panoramic radiographs. Future development of CNN-based models for this purpose should also consider different stages of dentition, such as the primary and mixed dentition stages, as well as the presence of various tooth conditions. Ultimately, an optimized CNN architecture can serve as the foundation for an automated tooth numbering system and for further artificial intelligence research on panoramic radiographs for a variety of purposes.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.1066-1080
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• 2024

SMART100 has a containment pressure and radioactivity suppression system (CPRSS) for passive containment cooling system (PCCS). This prevents overheating and over-pressurization of a containment through direct contact condensation in an in-containment refueling water storage tank (IRWST) and wall condensation in a CPRSS heat exchanger (CHX) in an emergency cool-down tank (ECT). The Korea Atomic Energy Research Institute (KAERI) constructed scaled-down test facilities, SISTA1 and SISTA2, for the thermal-hydraulic validation of the SMART100 CPRSS. Three separate effect tests were performed using SISTA1 to confirm the heat removal characteristics of SMART100 CPRSS. When the low mass flux steam with or without non-condensable gas is released into an IRWST, the conditions for mitigation of the chugging phenomenon were identified, and the physical variables were quantified by the 3D reconstruction method. The local behavior of the non-condensable gas was measured after condensation inside heat exchanger using a traverse system. Stratification of non-condensable gas occurred in large tank of the natural circulation loop. SISTA2 was used to simulate a small break loss-of-coolant accident (SBLCOA) transient. Since the test apparatus was a metal tank, compensations of initial heat transfer to the material and effect of heat loss during long-term operation were important for simulating cooling performance of SMART100 CPRSS. The pressure of SMART100 CPRSS was maintained below the design limit for 3 days even under sufficiently conservative conditions of an SBLOCA transient.

• Journal of the Korean Society for Library and Information Science
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• v.16
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• pp.281-327
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• 1989

This dissertation is presented in two major parts. The first part presented in Chapter 3 attempts to verify the major hypothesis of the present study that the research and development laboratories(hereafter referred to R&D laboratories), establishd withine industrial firms to develop new technologies needed for their own industrial activities, may have another but very important functions to bring information on the externally generated technologies to attention of their respective management decision makers, eventually resulting in the transfer of technology; and such information functions of the R&D laboratories may be better performed by well-organised laboratories than by poorly-organised ones. The second part presented in Chapters 4, 5, 6 and 7 discusses, after the preceding hypotheses has been verified, some desirable situations of the R&D laboratories in facilitating the flow of information on new technologies developed in the world into their industrial firms, centering on the organisational positions and the major fields of interest of the person in charge of the R&D centers, services of the library and technological information office supporting the R&D laboratories, and frequencies of direct contacts of research and development workers with experts in the world and of participation in various conferences, seminars, workshops, exhibitions, etc. Now that there is no recognised instrument and method available for direct measurement of volume of technological information transfered into a particular industrial firm, the number of technologies introduced into a given firm is employed in the present study as an analogous parametre indicating volume of technological information transfered into the firm during a particular period of time. A logical attempt to justify the use of the indirect paramentre is made in Chapter two. vidences needed to verify the hypotheses of the present study are collected through the various publications of the Korea Industrial Research Institutes and other agencies and institutions related to industrial research activities, and through responses to the questionnaire posted to a sample of the 66 R&D laboratories on 6 May 1987 and returned by 30 August of the same year. Some findings and conclusions made in the study are summarised as follows: (1) More information on externally developed technologies flows into the industrial firm with a R&D laboratory of its own than into the industrial firm without one, and naturally, more chances of transfer of technologies are given to the former than to the latter (see 3. 2) (2) After establishing an R&D laboratory, more technological information flows into the industrial firm than before establishing one (see 3. 3) (3) More technological information flows into the industrial firm with a well-organised R&D laboraory than into the firm with a poorly-organised one (see 3. 4) (4) More technological information flows into the ndustrial firm where the director of its R&D laboratory has status qualified to participate in the highest managerial decision making processes of the firm than into the industrial firm where the director does not have such status (see 4. 2) (5) More technological information flows into the industrial firm where the director of R&D laboratory does not hold other positions within the firm than into the industrial firm where the director holds other positions (see 4.3) (6) There is evidence showing that quantities of technological information transfered into industriali firms vary with the case that the major background of the director of the R&D laboratory is the same as the main field of R&D activities of his or her laboratery, the case that the director's background is partly related to the field of R&D activities of the laboratory, and the case that the director's major background is different from the field of R&D activities of the laboratory (see 4.4) (7) More technological information flows into the industrial firm with the director of its R&D laboratory appointed from among professional research and development workers than into the industrial firm with the director of its R&D laboratory appointed from among general managers (see 4.5) (8) More technological information flows into the industrial firm with its R&D laboratory which has established a library service unit within its own jurisdiction than into the industrial firm with its R&D laboratory which has established a library service unit within its own jurisdiction than into the industrial firm with its R&D laboratory which uses a library within the firm but outside the laboratory (see 5. 1) (9) More echnological information flows into the industrial firm with a technological information office of its own than into the industrial firm without such an office (see 5. 2) (10) More technological information flows into the industrial firm with a large research and development staff in its R&D laboratory than into the industrial firm with a small staff in its R&D laboratory (see 5. 2) (11) More technological information flows into the industrial firm with its R&D laboratory whose staff members more frequently contact experts in the conferences, seminars, symposiums, and workshops held in foreign countries and novelties in the world's major exhibitions than into the industrial firm with its R&D laboratory whose staff members less frequently contact such experts and novelties (see 6. 2 ; 6. 3)

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.85-90
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• 2017

The $TiCl_4$ as a blocking material is adsorbed in the mesoporous $TiO_2$ electron transfer layer(ETL) of the Perovskite solar cell to prevent the direct contact between the FTO electrode and the photoactive layer(AL), and facilitate the movement of the electrons between $TiO_2:TiCl_4$ ETL and Perovskite AL to improve the photoelectric conversion efficiency(PCE). The structure of the perovskite solar cell is FTO/$TiO_2:TiCl_4$/Perovskite($CH_3NH_3PbI_3$)/spiro-OMeTAD/Ag. It was investigated that the dipping time of the $TiO_2$ into $TiCl_4$ aqueous solution affects on the photoelectric characteristics of the device. By the dipping for 30 minutes, the PCE of the perovskite solar cell with the $TiO_2:TiCl_4$ ETL was the highest 10.46%, which is 27% higher than the cell with $TiO_2$ ETL. From SEM, EDS, and XRD characterization on the $TiO_2:TiCl_4$ ETL and the perovskite AL, it was measured that the decrease of the porosity of the $TiO_2$ layer, the detection of the Cl component by the $TiCl_4$ adsorption, the cube-type morphology of perovskite AL, and shift of the $PbI_2$ peak of the perovskite AL. From these results, it was confirmed that the $TiO_2:TiCl_4$ ETL and the perovskite AL were formed.

• Economic and Environmental Geology
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• v.52 no.5
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• pp.395-407
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• 2019

The duplex system has been considered as an important slip-transfer mechanism to evaluate the evolution of orogenic belts. Duplexes are generally found in the hinterland portion of fold-thrust belts and accommodate large amounts of total shortening. Thus, understanding its geometric and kinematic evolution can give information to evaluate the evolution of the entire orogenic belt. Duplexes are recognized as closed-loop thrust traces on map view, indicating higher connectivity than imbricate fans. As originally defined, a duplex is an array of thrust horses which are surrounded by thrust faults including the floor and roof thrusts, and imbricate faults between them. Duplexes can accommodate regional layer-parallel shortening and transfer slip from a floor thrust to a roof thrust. However, an imbricate fault is not the only mean for layer-parallel shortening (LPS) and displacement transfer within duplexes. LPS cleavages and detachment folds can also play the same role. From this aspect, a duplex can be divided into three types; 1) fault duplex, 2) cleavage duplex and 3) fold duplex. Fault duplex can further be subdivided into the Boyer-type duplex, which was firstly designed duplex system in the 1980s that widely applied most of the major fold-thrust belts in the world, and connecting splay duplex, which has different time order in the emplacement of horses from those of the Boyer-type. On the contrary, the cleavage and fold duplexes are newly defined types based on some selected examples. In the Korean Peninsula, the Yeongwol area, the western part of the Taebaeksan Zone of the Okcheon Belt, gives an excellent natural laboratory to study the structural geometry and kinematics of the closed-loops by thrust fault traces in terms of a duplex system. In the previous study, the Yeongwol thrust system was interpreted by alternative duplex models; a Boyer-type hinterland-dipping duplex vs. a combination of major imbricate thrusts and their connecting splays. Although the high angled beds and thrusts as well as different stratigraphic packages within the horses of the Yeongwol duplex system may prefer the later complicate model, currently, we cannot choose one simple answer between the models because of the lack of direct field evidence and time information. Therefore, further researches on the structural field investigations and geochronological analyses in the Yeongwol and adjacent areas should be carried out to test the possibility of applying the fold and cleavage duplex models to the Yeongwol thrust system, and it will eventually provide clues to solve the enigma of formation and its evolution of the Okcheon Belt.