• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.5
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• pp.1653-1670
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• 2022

The fear that location privacy may be compromised greatly hinders the development of location-based service. Accordingly, some schemes based on the distributed architecture in peer-to-peer network for location privacy protection are proposed. Most of them assume that mobile terminals are mutually trusted, but this does not conform to realistic scenes, and they cannot make requirements for the level of location privacy protection. Therefore, this paper proposes a scheme for location attribute-based security authentication and private sharing data group, so that they trust each other in peer-to-peer network and the trusted but curious mobile terminal cannot access the initiator's query request. A new identifier is designed to allow mobile terminals to customize the protection strength. In addition, the caching mechanism is introduced considering the cache capacity, and a cache replacement policy based on deep reinforcement learning is proposed to reduce communications with location-based service server for achieving location privacy protection. Experiments show the effectiveness and efficiency of the proposed scheme.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4562-4572
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• 2014

The recent location-based services of smart-phones are some of the rapidly growing mobile technology. This paper proposes a technique for modifying the change cycle of location-based services according to the specific location using location based services. This technique shows that the cycle of the location-based services can be customized based on the location. As a result, this technique proposes a process that can reduce the waste of resources compared to the location based services of a constant cycle.

• Korean Journal of Oriental Medicine
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• v.16 no.2
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• pp.125-130
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• 2010

Objectives : The bone proportional cun and body cun have been used widely for the location of acupoints in oriental medical clinic. The aim of this study is to compare the two location methods. Methods : 21 students were examined for the location of 6 acupoints (each 2 points in the 3 parts of upper limb, abdomen, and lower limb) using the twe methods. The data of location were analyzed with t-test. Results : In the upper limb, the data from bone proportional cun and body cun were proved to be different significantly. However, there was no significant difference between the data from the two methods in the abdomen and lower limb. Conclusion : The results of this study demonstrate that the oriental medical doctors should be more careful in the choice of appropriate method for the location of acupoints in the upper limb, while it is not important whether they use bone proportional cun and body cun in the abdomen and lower limb.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.8
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• pp.2827-2848
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• 2021

Mobile Crowdsourcing (MCS) has become an emerging paradigm evolved from crowdsourcing by employing advanced features of mobile devices such as smartphones to perform more complicated, especially spatial tasks. One of the key procedures in MCS is to collect answers from mobile users (workers), which may face several security issues. First, authentication is required to ensure that answers are from authorized workers. In addition, MCS tasks are usually location-dependent, so the collected answers could disclose workers' location privacy, which may discourage workers to participate in the tasks. Finally, the overhead occurred by authentication and privacy protection should be minimized since mobile devices are resource-constrained. Considering all the above concerns, in this paper, we propose a lightweight and privacy-preserving answer collection scheme for MCS. In the proposed scheme, we achieve anonymous authentication based on traceable ring signature, which provides authentication, anonymity, as well as traceability by enabling malicious workers tracing. In order to balance user location privacy and data availability, we propose a new concept named current location privacy, which means the location of the worker cannot be disclosed to anyone until a specified time. Since the leakage of current location will seriously threaten workers' personal safety, causing such as absence or presence disclosure attacks, it is necessary to pay attention to the current location privacy of workers in MCS. We encrypt the collected answers based on timed-release encryption, ensuring the secure transmission and high availability of data, as well as preserving the current location privacy of workers. Finally, we analyze the security and performance of the proposed scheme. The experimental results show that the computation costs of a worker depend on the number of ring signature members, which indicates the flexibility for a worker to choose an appropriate size of the group under considerations of privacy and efficiency.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.2
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• pp.175-181
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• 2014

Location awareness is one of the key functions to build an U-city. Recently, many of works for the location-aware systems are emerging to be applied to on-going large-scale apartment complex. For example, when dwellers or cars with active tags are move in the apartment complex, the active tags broadcast their own identifiers periodically and receivers such that routers use this information to calculate the location of the active tags. Since the active tags can actually move between routers and coordinators, it requires a hand-off mechanism. In this paper, we investigate the hand-off problem occurred in location awareness system based on ZigBee active tags. We propose and analyze a new approach for handling the hand-off problem. Through a mathematical analysis, we show that our approach diminishes the quantity of packet transfer than ZigBee's approach.

• Investigative Magnetic Resonance Imaging
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• v.24 no.1
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• pp.21-29
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• 2020

Purpose: To investigate normal location of the peroneus longus tendon (PL) in the cuboid groove by evaluating it between ankles with no significant abnormality (asymptomatic group) and those with retromalleolar PL dislocation (dislocation group) using three-dimensional isotropic fast spin-echo (3D-FSE) magnetic resonance imaging (MRI) of the ankle. Materials and Methods: Thirty-six and 32 3D-FSE ankle MRI were assigned to the asymptomatic group and the dislocation group, respectively. Using multiplanar reformatted 3D-FSE, qualitative PL location (i.e., outside, overlying, and inside in relation to the cuboid groove), quantitative PL location (i.e., distance between the proximal margins of PL and cuboid groove), and cuboid groove size were measured in lateral, middle, and medial levels of the cuboid groove. Results: In the asymptomatic group, 64%, 42%, and 11%, respectively, had the outside or overlying-located PL in lateral, middle, and medial levels of the cuboid groove and the quantitative location gradually decreased from lateral to medial level. Qualitative and quantitative PL locations were not significantly different between the asymptomatic group and dislocation group. Cuboid groove size showed significant negative correlation with quantitative PL location in both groups. Conclusion: Outside- or overlying-located PL in lateral and middle levels of the cuboid groove would be a normal finding, regardless of PL status at the retromalleolar level.

• Journal of Preventive Medicine and Public Health
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• v.29 no.2 s.53
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• pp.215-225
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• 1996

Decentralization to local governments and amending of Health Center Law are to promote the efforts of health planning at the level of local agencies. In the health facility planning, it is important to take into account that what to be built, where to be located, how far should be service area and so forth, because health facilities are immovable, and require capital as well as personnel and consumable supplies. The aim of our study, answering to the question of 'where to be located?', is to determine the best location of urban health sub-center. At the local level, planning is the matter of finding the best location of specific facilitiy, in relation to population needs. We confine the accessibility, which is basic to location planning, to geographic one. Location-Allocation Model is used to solve the problem where the location is to maximize geographic accessibility. To minimize the weighted travel distance, objective function, $R_k=\sum{\sum}a_{ij}w_{i}d_{ij}$ is used. Distances are measured indirectly by map measure-meter with 1:25,000 Suwon map, and each potential sites, 10 administrative Dongs in Kwonson Gu, Suwon, are weighted by each number of households, total population, maternal age group, child age group, old age group, Relief for the livelihood, and population/primary health clinics. We find that Kuwoon-Dong, Seodun-Dong, Seryu3-Dong, according the descending orders, are best sites which can minimize the weighted distance, and conclude that it is reasonable to determine the location of urban health sub-center among those sites.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.1
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• pp.31-36
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• 2003

The causes of disease as well as the mechanisms that result in the presenting signs and symptoms of patients are basic elements in oriental medicine. The location of the disease is the region on which the cause and the nature of the disease acts. Syndrome reflects the cause of the disease and the pathological change and the location of the disease. It is customary to classify the location of the disease into two major categories. First is based on the exterior and interior and the second is based on the five internal organs. Exterior syndrome is caused by the invasion of exopathogen in skin and hair, channels and collaterals. Interior syndrome refers to the syndrome located deeply in the interior of the body such as five internal organs. The location of the disease is very important to distinguish different syndromes in the diagnosis and the treatment of a disease.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.7 s.337
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• pp.1-6
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• 2005

Now that the reduction of the cell size in order to serve the increasing subscribers has raised the frequency of the location update, it has increased the cost of location management. In this paper, we show that the location management strategy based on the call arrival probability(CAP) can reduce the cost of the location management by analyzing that cost in this strategy which was proposed in [1] to reduce the cost of the location management in mobile communication. And we compare the location management cost by analyzing with that by simulating.

• Journal of Gastric Cancer
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• v.11 no.2
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• pp.86-93
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• 2011

Purpose: When performing a laparoscopic assisted gastrectomy, a function-preserving gastrectomy is performed depending on the location of the primary gastric cancer. This study examined the incidence of lymph node metastasis by the lymph node station number by tumor location to determine the optimal extent of the lymph node dissection. Materials and Methods: The subjects consisted of 1,510 patients diagnosed with gastric cancer who underwent a gastrectomy between 1996 and 2005. The patients were divided into three groups: upper, middle and lower third, depending on the location of the primary tumor. The lymph node metastasis patterns were analyzed in the total and early gastric cancer patients. Results: In all patients, lymph node station numbers 1, 2, 3, 7, 10 and 11 metastases were dominant in the cancer originating in the upper third, whereas station numbers 4, 5, 6 and 8 were dominant in the lower third. In early gastric cancer patients, the station number of lymph nodes with a metastasis did not show a significant difference in stage pT1a disease. On the other hand, a metastasis in lymph node station number 6 was dominant in stage pT1b disease that originated in the lower third of the stomach. Conclusions: When performing a laparoscopic-assisted gastrectomy for early gastric cancer, a limited lymphadenectomy is considered adequate during a function-preserving gastrectomy in mucosal (T1a) cancer. On the other hand, for submucosal (T1b) cancer, a number 6 node dissection should be performed when performing a pylorus preserving gastrectomy.