• Korean Journal of Radiology
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• v.23 no.10
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• pp.1019-1027
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• 2022

Objective: Thyroidectomy bed lesions frequently show suspicious ultrasound (US) features after thyroid surgery. Fine-needle aspiration (FNA) may not provide definitive pathological information about the lesions. Although core-needle biopsy (CNB) has excellent diagnostic performance in characterizing suspicious thyroid nodules, no published studies have evaluated the performance of CNB specifically for thyroidectomy bed lesions. Therefore, we aimed to evaluate the diagnostic performance and safety of CNB for characterizing thyroidectomy bed lesions. Materials and Methods: A total of 124 thyroidectomy bed lesions in 113 patients (79 female and 34 male; age, 23-85 years) who underwent US-guided CNB between December 2008 and December 2020 were included. We reviewed the US imaging features of the target lesions and the histories of previous biopsies. The pathologic results, diagnostic performance for malignancy, and complications of CNB were analyzed. Results: All samples (100%) obtained by CNB were adequate for pathological analysis. Pathological analysis revealed inconclusive results in two lesions (1.6%). According to the reference standard, 50 lesions were ultimately malignant (40.3%), and 72 were benign (58.1%), excluding the two inconclusive lesions. The performance of CNB for diagnosing malignant thyroidectomy bed lesions in the 122 lesions had a sensitivity of 98.0% (49/50), a specificity of 100% (72/72), positive predictive value of 100% (49/49), and negative predictive value of 98.6% (72/73). Eleven lesions were referred for CNB after prior inconclusive FNA results in thyroidectomy bed lesions, for all of which CNB yielded correct conclusive pathologic diagnoses. According to the pathological analysis of CNB, there were various benign lesions (58.9%, 73/124) besides recurrence, including benign postoperative lesions other than suture granuloma (32.3%, 40/124), suture granuloma (15.3%, 19/124), remnant thyroid tissue (5.6%, 7/124), parathyroid lesions (4%, 5/124), and abscesses (1.6%, 2/124). No major or minor complications were associated with the CNB procedure. Conclusion: US-guided CNB is accurate and safe for characterizing thyroidectomy bed lesions.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.3940-3955
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• 2023

A new method of numerical simulating prediction and decontamination effect evaluation for abrasive jet decontamination to radioactively contaminated metal is proposed. Based on the Computational Fluid Dynamics and Discrete Element Model (CFD-DEM) coupled simulation model, the motion patterns and distribution of abrasives can be predicted, and the decontamination effect can be evaluated by image processing and recognition technology. The impact of three key parameters (impact distance, inlet pressure, abrasive mass flow rate) on the decontamination effect is revealed. Moreover, here are experiments of reliability verification to decontamination effect and numerical simulation methods that has been conducted. The results show that: ⁶⁰Co and other homogeneous solid solution radioactive pollutants can be removed by abrasive jet, and the average removal rate of Co exceeds 80%. It is reliable for the proposed numerical simulation and evaluation method because of the well goodness of fit between predicted value and actual values: The predicted values and actual values of the abrasive distribution diameter are Ф57 and Ф55; the total coverage rate is 26.42% and 23.50%; the average impact velocity is 81.73 m/s and 78.00 m/s. Further analysis shows that the impact distance has a significant impact on the distribution of abrasive particles on the target surface, the coverage rate of the core area increases at first, and then decreases with the increase of the impact distance of the nozzle, which reach a maximum of 14.44% at 300 mm. It is recommended to set the impact distance around 300 mm, because at this time the core area coverage of the abrasive is the largest and the impact velocity is stable at the highest speed of 81.94 m/s. The impact of the nozzle inlet pressure on the decontamination effect mainly affects the impact kinetic energy of the abrasive and has little impact on the distribution. The greater the inlet pressure, the greater the impact kinetic energy, and the stronger the decontamination ability of the abrasive. But in return, the energy consumption is higher, too. For the decontamination of radioactively contaminated metals, it is recommended to set the inlet pressure of the nozzle at around 0.6 MPa. Because most of the Co elements can be removed under this pressure. Increasing the mass and flow of abrasives appropriately can enhance the decontamination effectiveness. The total mass of abrasives per unit decontamination area is suggested to be 50 g because the core area coverage rate of the abrasive is relatively large under this condition; and the nozzle wear extent is acceptable.

• Journal of the Korean Regional Science Association
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• v.40 no.1
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• pp.37-51
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• 2024

To respond to local extinction, South Korea, under the leadership of the Ministry of the Interior and Safety, identified depopulated areas in 2021 and launched the Local Extinction Response Fund in 2022. However, due to its early stage of implementation, analyzing the characteristics and changes of policy response to local extinction at the central government level remains a challenge. In contrast, Japan, facing similar issues of local extinction as South Korea, has established a robust central government-led response system based on the Regional Revitalization Act and the Comprehensive Strategy and Basic Policy on Community-Population-Job Creation. Hence, this study examines Japan's policy responses to local extinction by analyzing the first and second periods of the Comprehensive Strategy and Basic Policy on Community-Population-Job Creation. For the analysis, topic modeling was employed to enhance text analysis efficiency and accuracy, complemented by expert interviews for validation. The results revealed that the first-period strategy's topics encompassed economy and society, start-up, local government, living condition, service, and industry. Meanwhile, the second-period strategy's topics included resource, the New Normal, woman, digital transformation, industry, region, public-private partnership, and population. The analysis highlights that the policy target, policy direction, and environmental change significantly influenced these policy shifts.

• Korean Security Journal
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• no.36
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• pp.255-292
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• 2013

Burglary (also called breaking and entering and sometimes housebreaking) is a crime, the essence of which is illegal entry into a building for the purposes of committing an offence. It is one of the most common types of crime and also a serious issue for every society. A house that is left insecure is an accessible and attractive target for burglars and therefore burglary resistance test & certification system for doors and windows has been developed in many countries. This paper explores several advanced foreign burglary resistance test/certifcation cases (the British SBD, the Dutch KOMO SKH/SKG, the Japanese CP mark, the Australian Standard Certification) for security products and domestic test/certification systems for fire safety products as a comparative study so that any improvement points can be gained for South Korea in the field of security product performance. The comparative analysis results show that South Korea is far behind the security product certification system and needs a lot of improvement in the system by benchmarking foreign cases. The domestic test/certification systems for fire safety products also give some insights for burglary-related security products' performance certification system in Korea. Overall, the need for relevant rules and regulations, the establishment of standards regarding testing and certification, including certified security +hardware product in building security certification system, performance testing as well as production testing (i.e. quality management system evaluation), the basic competency of testers, incentive system for certified/high quality security products were suggested in order to make an optimal model for the security production performance testing and certification system in Korea.

• Asia pacific journal of information systems
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• v.17 no.4
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• pp.165-186
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• 2007

With the advent of a wide variety of Internet shopping malls, consumers can choose a best appealing shopping mall from among the Bricks-and-Clicks and Pure-Player malls. Pure-Players launched their operation grandiosely with the early stage of Internet use in 1995. However, after the burst of Dot-com company bubbles in 1997, Pure-Players introduce various types of business models to meet potential needs of consumers. While Pure-Players suffer skeptical views from market analysts as well as consumers, traditional offline companies learned important lessons from Dot-com companies collapse phenomena, and expanded their business channels into online in the name of Bricks-and-Clicks. Nowadays, Bricks-and-Clicks successfully establish in the market as one of reliable business partners among consumers. Therefore, it is no surprise that recent competitions between Bricks-and Clicks and Pure-Players become fiercer than ever to attract potential customers to their websites. In this situation, consumers can choose a shopping mall to their best satisfaction. Consumers can enjoy both offline and online options for shopping because Bricks-and Clicks provide both offline and online channels to consumers, which is compared with Pure-Players offering only online channel. Offline channel is unique in providing consumers with chances to touch and feel target products and services. Meanwhile, online channel is considered very viable and convenient shopping options for consumers. In this respect, it is easily assumed that consumers will show different online shopping behavior when they have to choose either Bricks-and-Clicks mall or Pure-Player mall for the sake of shopping. Remaining research issue in this case is how much consumers' schema would influence online shopping behavior between Bricks-and-Clicks and Pure-Players. Basically, schema is a framework for synthetic information recognition that individual consumers have and is very characteristic in that it focuses not on fragmentary facts but on the combination of various causes affecting results. Consumers' schema is closely represented by trust, structural assurance, and perceived relative advantage towards a specific type of shopping mall. In literature, there exist a lot of studies comparing Bricks-and-Clicks and Pure-Players. However, there is no study to pursue the analysis of consumer behaviors comparing Bricks-and Clicks and Pure-Players from the schema perspective. Therefore, this study aims to investigate this research gap. Empirical analysis is adopted by garnering valid questionnaires from 514 Internet shopping mall users. 237 were mainly using Bricks-and-Clicks for shopping, while 277 were found to visit Pure-Players for shopping. PLS was applied to analyze the survey data to verify the proposed research hypotheses. Findings from the empirical test results are as follows. First, consumers perceive more trust and relative advantage in Pure-Players, comparing with Bricks-and-Clicks. This result is against widely-accepted perception that Bricks-and-Clicks would be perceived by consumers as more trustworthy and relatively advantageous because they have offline reputation and stores. Therefore, it becomes more obvious that Internet is becoming daily necessaries, and consumers increasingly feel very comfortable in using the Internet for their own personal purposes. Second, consumers have firm faith in transaction safety, regardless Bricks-and-Clicks and Pure-Players. This seems due to the fact that most of shopping malls showing dubious transaction safety have no place in the market. In a nutshell, empirical results tell us that Pure-Players will grow very much in the future, to the extent that consumers perceive no difference in comparison with Bricks-and-Clicks. Besides, consumers' schema accumulated through trust and perceived relative advantage plays crucial role in determining consumer behavior.

• Ecology and Resilient Infrastructure
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• v.2 no.4
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• pp.265-273
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• 2015

It is the better to take preventative measures against the natural intrusion in advance from invasive alien species that reduce biodiversity and cause economic loss to humans. If the prevention of intrusion and spread fails, we need to make active control and eradication. This study aims to introduce nutria (Myocastor coypus) control cases performed in the United Kingdom and the United States and to provide information for the contribution of nutria management measure improvements. The nutria eradication campaign in the United Kingdom was developed as a long-term plan based on sufficient understanding on the management target and objective and suitable support. Sufficient information on nutria was accumulated and the management strategy was flexibly modified according to the changes in management that were proactively reflected in the field. Regarding the eradication project at Chesapeake Bay in the United States, based on long-term ecological information, more advanced capture technology than in the United Kingdom were introduced and the eradication plan, strategy and implementation were configured by analyzing the strengths and weaknesses of the eradication campaign in the United Kingdom. The successful cases in the United Kingdom and the United State provide an information on how to improv the nutria management measure. For the eradication of nutria, it is necessary to reach a consensus between stakeholders and to form a consultative group between related organizations for periodic communication. Opinions on the field must be actively accepted in the consultation process for strategy and policy decision, and the eradication plan needs to be developed based on a management index. The eradication plan is required to be managed, evaluated and adjusted in a systematic way. Scientific management must be introduced and the management performance must be evaluated objectively so that a practical plan can be flexibly adjusted. It is also required to secure a long-term budget support and a stable organization and to input a concentrated budget at the proper period when there is high efficiency of eradication.

• Journal of Food Hygiene and Safety
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• v.16 no.1
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• pp.21-26
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• 2001

Risk assessment traditionally are conducted on individual chemicals; however, humans are exposed to multiple chemicals in daily life. The organophosphorus (OP) pesticides are considered in a single risk assessment because they act by a common mechanism of toxicity, and there is likely to be expose to multiple OP pesticides simultaneously or sequentially. The OP pesticides act by inhibiting the enzyme acetylcholinesterasc (AChE) and have available extensive database. AChE is widely distributed throughout the body, most importantly in the nervous system. Inhibition of AChE results in accumulation of acetylcholine in the nervous system that results in clinical signs of cholinergic toxicity, including increased salivation and lacrimation, nausea and vomiting, muscle fasciculation, lethargy and fatigue, among others. To conduct an exposure assessment for pesticides in the diet, we need to know the food consumption patterns of the populations, and the pesticide residue levels in the foods that are consumed. This study was conducted to identify cumulative dietary risk due to multiple OP pesticides that can be exposed through various foods. Total 22 food samples including cereals, vegetables and fruits were collected randomly two times from food markets in several sites (4 cities). The subjected foods were selected by regarding of highly consumed foods to general Korean people. The 12 OP pesticides including Acephate, Azinphos-methyl, Chlorpyrifos, and Diazinon were monitored. For the exposure assessment, general adult group of 60 kg body weight was regarded as target population and food consumption data suggested by Lee et al. (2000) were used as consumed value of individual food. Analyses of samples for OP pesticides have been carried out according to the multiclass multiresidue analysis method and acephate and methamidophos analysis method of Korea Food Code. In general the levels of OP pesticides found in the food samples were very low or not detected.

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.43-50
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• 2015

In this study, single PCR and multiplex PCR tests were examined for identification of four types of squid species (giant squid, cuttlefish, octopus, beka squid) purchased from fish market as well as aquatic processed products in Busan. To design the specific primers against each species, the nucleotide sequences of the mitochondrial 16s rRNA gene of Architeuthis dux, Todarodes pacificus, Enteroctopus dofleini, Enteroctopus megalocyathus, Uroteuthis chinensis, Uroteuthis duvauceli, Uroteuthis edulis groups were analyzed for the identification of each species registered in the GeneBank (www.ncbi.nlm.nih.gov) and have been used for comparative analysis. In order to obtain the size variation of amplified fragments on multiplex PCR, we designed KOJ-F, OJ-F, OCT-F, HAN-F, ALLR primers for each species. The optimal PCR conditions and primers were selected for four types of squid species to determine target base sequences in its PCR products. In the case of single PCR, giant squid was only amplified by KOJ-F/ALLR primer; cuttlefish was only amplified by OJ-F/ALLR primer; octopus was only amplified by OCT-F/ALLR primer; and beka squid was only amplified by HAN-F/ALLR primer. For multiplex PCR, the mixture of four kinds of genomic DNA (giant squid, cuttlefish, octopus, beka squid) been prepared as a template and used together with the mixture of KOJ-F/OJ-F/OCT-F/HAN-F/ALLR primers in the reaction. By the multiplex PCR, it is confirmed that four samples are correspond to multiple simultaneous amplicon. Finally, we validated the established methods of multiplex PCR in the aquatic processed products. Although the mitochondrial 16s rRNA primers used in this study was useful as a marker for detection of each species among them, the study indicated that the established multiplex PCR method can be more useful tool for monitoring the processed products.

• Journal of Nutrition and Health
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• v.53 no.5
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• pp.547-561
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• 2020

Purpose: This study was conducted to segment the delivery food market and to develop customized products and services. Methods: This study analyzed 636 responses collected from customers who ordered delivery food. Statistical analyses were conducted using the SPSS program (ver. 25.0) for frequency analysis, χ²-test, one-way analysis of variance, factor analysis, and cluster analysis. Results: Four factors were extracted by exploratory factor analysis (safety-orientation, convenience-orientation, taste-orientation, and economy-orientation) to explain the consumers' food-related lifestyles. The results of cluster analysis indicated that the 'low-interest group', 'convenience and economy-oriented group', and 'gourmet and economy-oriented group' should be regarded as the target segments. Characteristic analysis of each cluster showed that lowinterest group had higher rates of married (67.1%) and living with family (85.4%) than other clusters. The convenience and the economy-oriented group had higher rates of living alone (28.9%) than others. The gourmet and the economy-oriented group had a higher percentage of unmarried (62.0%) than the others. In addition, the average age of convenience and economy-oriented group (32.3 years) and gourmet and economy-oriented group (32.5 years) were significantly lower than the safety seeker (40.0 years) (p < 0.001). Difference analysis of the consumption practice according to the cluster, revealed significant differences in the order frequency (p < 0.001), main day to order (p < 0.05), source of information about delivery food (p < 0.001), order method (p < 0.001), and co-consumer (p < 0.01). In addition, the convenience and the economy-oriented group had significantly higher overall satisfaction than the others (p < 0.001). Conclusion: These findings suggest that customer segmentation based on a food-related lifestyle can be used to build a successful marketing strategy. Therefore, restaurant managers and delivery platform operators should consider developing products and services according to the segmentation to maximize customer satisfaction.

• Korean Security Journal
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• no.22
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• pp.169-196
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• 2010

Although more priority is given to politicians from the aspect that they represent people and decide the future of country, the current situation is that politicians are not free from terrorism because of insufficient guard-concerned law, negative social recognition and increased crime and terrorism. The measure for politician terrorism shall be handled from the aspect of national security rather than public peace. For the purpose, basic legal foundation shall be prepared and specialized guard technique considering specialty of politician shall be established. Basic solution shall be established by reinforcing law against politician terrorism and establishing new law from the national viewpoint. The guard for politician has two faces that both of safety of guard target and voting intention of voter shall be met at the same time. Although special guard technique is required for guarding politician, current situation is that it is not researched professionally. In relation to the measure to develop the system of protection for politician, First, the study suggested legal foundation for politician guard. Although the 17th National Assembly proposed revised legal plan to protect politician from terrorism, it is suspended, expired and abolished now. The legal plan presented by members of the National Assembly was simply restricted to the scope of public guard. The study divided establishment of legal foundation into two things. The first one is the dispatch type of effective public guard and the second one is the transfer to private guard. Second, the study suggested environmental development method of politician guard. in the environment of politician guard, the study suggested improvement and development method by analyzing social recognition, politician's mind and voter's mind psychologically. After the beginning of human society, if human race is continued, political activity won't disappear. It is obvious that the safety of political leader is very important issue for human race because he plays the role to decide the future of human. In the future, more specialized, effective law shall be prepared and deeper study of scholar shall be performed.