• Journal of Korean Port Research
• /
• v.11 no.1
• /
• pp.85-99
• /
• 1997

The improvements of berth productivity is closely related to berth/port systems and its relationship extends to the overall pattern of port development/logistics, transport and trade. Since ports in general and berths in specific function as a bridge transferring seaborne cargoes from seaside to landside and vice versa, berth productivity improvements should be considered in terms of the total system in which the cargoes are transported from origin to destination via berths/ports. In that respect, the objective of this study is to improve berth productivity which is a vital factor in the strategic planning in port development and operation and logistics. According to a literature survey on the subject, the contents of the studies have been limited to either a macro-perspective or a micro-perspective which is only a partial solution to the problem. Hence, this limitation requires an integrated approach to find and ultimate solution, which should be considered not separately, but as a whole. The contents and scope of this study cover the improvements of berth productivity in conjunction with strategic planning in port development. efficient operation and logistics from two different viewpoints, macro- and micro-perspective. After that, a combination of these two perspectives is applied to the integrated approach due to lacking a comprehensive perspective from either macro-approach or micro-approach. In reality, a port itself is a complex and dynamic organization. Therefore, a comprehensive insight needs an integrated approach for the long-term national economic development. In this approach, the utmost importance is how to find the bottlenecks and to solve the problems effectively from the beginning stage in port development. In conclusion, derived from the macro- and micro-perspective. the attempt to establish an integrated approach is the merit of this study, which is required as a comprehensive measure since none of the two can be a solution independently. In terms of reinforcing this study, it needs further empirical research due to the restriction of the theoretical method of this paper. Consequently, the reinforced research will be able to enhance the integrated approach on the basis of the conceptual perspective.

• Journal of Navigation and Port Research
• /
• v.32 no.8
• /
• pp.645-652
• /
• 2008

The interest on the marine leisure sports is rapidly increasing with the advent of the five-day week and with increments of GNP. The self-governing bodies are trying to drag large investments into the marine leisures industry through international exhibitions and yacht rallies. Unfortunately, the demands in the domestic area don't increase differently from those demand patterns in the advanced countries. In this study, several suggestions for vitalizations on the marine leisure industry are made after surveying the recognition degree of the domestic people on the marine leisures and the current states of their spending on the marine leisures. As results, it has been shown that the policies based upon negative factors coming from negative understandings on the leisure activities should be largely revised. Further, it seems that the policies for the preparations of the laws and the regulations for the marine leisures as well as for the R&D policies should be taken systematically so that the infra structures are constructed while improving the negative understandings on the leisures. The fundamental databases investigated in this study will help the policy makers and the investors reduce the risks of the policy and the investments in the field of marine leisure sports.

• International Commerce and Information Review
• /
• v.15 no.2
• /
• pp.429-455
• /
• 2013

This paper investigates the extent and scope of electronization of Letter of Credit and examines the obstacles in the course of electronization of Letter of Credit. For this purpose, this paper adopts two track methodologies. First, we study the electronization of Letter of Credit in the macro perspective. It means that we analyze the scope and the extent of electronization of electronic Letter of Credit in the national economy as a whole. Second, we utilize the case study approach to examine the electronization of Letter of Credit in micro perspective. In other words we examine individual commercial banks in Korea. For this purpose, we analyze the data from two commercial banks out of four largest domestic banks in Korea. For example, we select two commercial banks in Korea and ask current status of electronization of Letter of Credit, i.e, the utilization of EDI L/C, e-L/C, and e-B/L. A major finding of our study is that the extent of electronization is not negligible in micro perspective as well as in macro perspective. In micro perspective, two commercial banks utilize EDI letter of credit in a critical sense. On the other hand, they seldom uses e-L/C and e-B/L in international transaction. This study shows that major bottlenecks for the electronization of Letter of Credit are pessimistic perception of SME entrepreneurs toward the electronization of Letter of Credit and the high costs of system building. We conclude that unlike superficial perception, there is a considerable progress toward the electronization of Letter of Credit in micro perspective.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.418-418
• /
• 2008

The electrochemical etching of silicon in HF-based solutions is known to form various types of porous structures. Porous structures are generally classified into three categories according to pore sizes: micropore (below 2 nm in size), mesopore (2 ~ 50 nm), and macropore (above 50 nm). Recently, the formation of macropores has attracted increasing interest because of their promising characteristics for an wide scope of applications such as microelectromechanical systems (MEMS), chemical sensors, biotechnology, photonic crystals, and photovoltaic application. One of the promising applications of macropores is in the field of MEMS. Anisotropic etching is essential step for fabrication of MEMS. Conventional wet etching has advantages such as low processing cost and high throughput, but it is unsuitable to fabricate high-aspect-ratio structures with vertical sidewalls due to its inherent etching characteristics along certain crystal orientations. Reactive ion dry etching is another technique of anisotropic etching. This has excellent ability to fabricate high-aspect-ratio structures with vertical sidewalls and high accuracy. However, its high processing cost is one of the bottlenecks for widely successful commercialization of MEMS. In contrast, by using electrochemical etching method together with pre-patterning by lithographic step, regular macropore arrays with very high-aspect-ratio up to 250 can be obtained. The formed macropores have very smooth surface and side, unlike deep reactive ion etching where surfaces are damaged and wavy. Especially, to make vertical microwire or nanowire arrays (aspect ratio = over 1:100) on silicon wafer with top-down photolithography, it is very difficult to fabricate them with conventional dry etching. The electrochemical etching is the most proper candidate to do it. The pillar structures are demonstrated for n-type silicon and the formation mechanism is well explained, while such a experimental results are few for p-type silicon. In this report, In order to understand the roles played by the kinds of etching solution and mask patterns in the formation of microwire arrays, we have undertaken a systematic study of the solvent effects in mixtures of HF, dimethyl sulfoxide (DMSO), iso-propanol, and mixtures of HF with water on the structure formation on monocrystalline p-type silicon with a resistivity with 10 ~ 20 $\Omega{\cdot}cm$. The different morphological results are presented according to mask patterns and etching solutions.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.11 no.2
• /
• pp.151-158
• /
• 2016

The HSA resolves an old problem with existing CPU and GPU architectures by allowing both units to directly access each other's memory pools via unified virtual memory. In a physically realized system, however, frequent data exchanges between CPU and GPU for a virtual memory block result bottlenecks and coherence request overheads. In this paper, we propose Fusion Processor Architecture for efficient access of main memory from both CPU and GPU. It consists of Job Manager, Re-mapper, and Pre-fetcher to control, organize, and distribute work loads and working areas for GPU cores. These components help on reducing memory exchanges between the two processors and improving overall efficiency by eliminating faulty page table requests. To verify proposed algorithm architectures, we develop an emulator based on QEMU, and compare several architectures such as CUDA(Compute Unified Device Architecture), OpenMP, OpenCL. As a result, Proposed fusion processor architectures show 198% faster than others by removing unnecessary memory copies and cache-miss overheads.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.12
• /
• pp.71-81
• /
• 2011

The EMR management services can monitoring the patients' record with any doctors in any hospital by using the internet and smartphones online. To handle the real time, multidimensional, continuous data, database management systems (DBMS) must cope with high insert rates for updates, however the traditional DBMS suffers from processing these kinds of data due to its serious design bottlenecks. So the researchers put forward to Data Stream Management System (DSMS). In this paper we describe the real-time Data Stream Server for Continuity of Care Record (CCR) that including continuos query processor. This system is compiled with DSMS and DBMS in EMR system for processing and monitoring the coming CCR data stream, and also storing the processed result with high-efficiency. The system enables users not only to query stored CCR information from DBMS, but also to execute continue query on real-time CCR Data Stream, and health information can be transferred between different healthcare providers that would reduce medical error. At last, we develop a IPhone mobile application to test the proposed real-time data stream server.

• Journal of KIISE:Software and Applications
• /
• v.32 no.10
• /
• pp.1003-1012
• /
• 2005

The most significant difference of embedded systems from general purpose systems is that embedded systems are allowed to use only limited resources including battery and memory. Especially, the number of applications increases which deal with multimedia data. In those systems with high data computations, the delay of memory access is one of the major bottlenecks hurting the system performance. As a result, many researchers have investigated various techniques to reduce the memory access cost. Most programs generally have locality in memory references. Temporal locality of references means that a resource accessed at one point will be used again in the near future. Spatial locality of references is that likelihood of using a resource gets higher if resources near it were just accessed. The latest embedded processors usually adapt cache memory to exploit these two types of localities. Processors access faster cache memory than off-chip memory, reducing the latency. In this paper we will propose the enhanced dynamic allocation technique for structure-type data in order to eliminate unused memory space and to reduce both the cache miss rate and the application execution time. The proposed approach aggregates fields from multiple records dynamically allocated and consecutively remaps them on the memory space. Experiments on Olden benchmarks show $13.9\%$ L1 cache miss rate drop and $15.9\%$ L2 cache miss drop on average, compared to the previously proposed techniques. We also find execution time reduced by $10.9\%$ on average, compared to the previous work.

• Journal of Internet Computing and Services
• /
• v.18 no.2
• /
• pp.21-30
• /
• 2017

IoT(Internet of Things) can enable networking and computing using any devices is rapidly proliferated. In the existing IoT environment, bottlenecks and service delays can occur because it processes data and provides services to users using central processing based on Cloud. For this reason, Edge Computing processes data directly in IoT nodes and networks to provide the services to the users has attracted attention. Also, numerous researchers have been attracted to intelligent service efficiently based on Edge Computing. In this paper, expert system-based context awareness scheme for Edge Computing in IoT environment is proposed. The proposed scheme can provide customized services to the users using context awareness and process data in real-time using the expert system based on efficient cooperations of resource limited IoT nodes. The context awareness services can be modified by the users according to the usage purpose. The three service modes in the security system based on smart home are used to test the proposed scheme and the stability of the proposed scheme is proven by a comparison of the resource consumptions of the servers between the proposed scheme and the PC-based expert system.

• Journal of Biosystems Engineering
• /
• v.28 no.6
• /
• pp.517-524
• /
• 2003

There have been worldwide research and development efforts to automate various processes of bio-production and those efforts will be expanded with priority given to tasks which require high intensive labor or produce high value-added product and tasks under hostile environment. In the field of bio-production capabilities of the versatility and robustness of automated system have been major bottlenecks along with economical efficiency. This paper introduces a new concept of automation based on tole-operation, which can provide solutions to overcome inherent difficulties in automating bio-production processes. Operator(farmer), computer, and automatic machinery share their roles utilizing their maximum merits to accomplish given tasks successfully. Among processes of greenhouse watermelon cultivation tasks such as pruning, watering, pesticide application, and harvest with loading were chosen based on the required labor intensiveness and functional similarities to realize the proposed concept. The developed system was composed of 5 major hardware modules such as wireless remote monitoring and task control module, wireless remote image acquisition and data transmission module, gantry system equipped with 4 d.o.f. Cartesian type robotic manipulator, exchangeable modular type end-effectors, and guided watermelon loading and storage module. The system was operated through the graphic user interface using touch screen monitor and wireless data communication among operator, computer, and machine. The proposed system showed practical and feasible way of automation in the field of volatile bio-production process.

• Journal of KIISE:Computer Systems and Theory
• /
• v.31 no.11
• /
• pp.626-634
• /
• 2004

In a client-server model, network server systems suffer from both heavy communication and computational loads. While communication channels become increasingly speedy, the existing protocol stack architectures still include mainly three performance bottlenecks of protocol stack processing, system call, and network interrupt overheads. To address these obstacles, in this paper we present a host-independent network system where a network interface card (NIC) is utilized in an efficient manner. First, by offloading network-related portion to the NIC, the host can fully utilize its processing power for other useful purposes. Second, it eliminates the system call overhead, such as context-switching and memory copy operations, since the host communicates with the NIC through its user-level libraries. Third, it a] so reduces the network interrupt operation count as the host handles the interrupt in a segment instead of a packet. The experimental results show that the proposed network system reduces the host CPU overhead for communication system by 68-71%. It also shows that the proposed system improves the communication speed by 11-83% under heavy computational and communication load conditions.