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This paper presents a comprehensive review of performance evaluation and optimization (PEO) methodologies for sixth-generation (6G) networks. It systematically analyzes the key performance indicators (KPIs) defined by major standardization bodies such as ITU-R, 3GPP, IEEE, & TIA and industry fora such as 5G-PPP, 6G-RIC, NGMN, and 6G-IA. Beyond summarizing KPI targets, this study classifies evaluation tools and AI-driven optimization frameworks into a unified taxonomy, highlighting how artificial intelligence enables adaptive, sustainable, and cross-layer performance control. Comparative synthesis reveals that most AI-driven approaches remain simulation-centric, lack benchmark alignment across KPIs, and face challenges in scalability, trustworthiness, and real-time inference. The paper concludes by identifying research gaps in AI-driven PEO frameworks and emphasizing future directions toward autonomous, energy-efficient, and explainable 6G systems.

Note that 40% of the world’s population, three billion people, live within 100 km of the ocean or seashore surfaces. To explore and experience marine life, human activities in ocean-based environments are increasing day-by-day. To make human activities safer and stronger, highly efficient and reliable wireless communication is crucial for conveying any unnatural things that occur in oceans. Exploring the vast environment is difficult because of its rapidly changing characteristics, which creates various levels of skip-zone, resulting in the loss of information. A re-configurable intelligent surface (RIS)-assisted optical link is employed to mitigate the effects of skip-zones and enable high-speed and efficient communication links. In addition to this, it is also necessary to convey information to the coastal line through a RIS-assisted free-space optical (FSO) link. In this study, we propose a RIS-assisted dual-hop underwater wireless optical communication (UWOC)-FSO communication system. For the proposed RIS-based dual-hop UWOC-FSO system, closed-form expressions for the outage probability (OP), bit error rate (BER) for coherent and non-coherent type binary phase-shift keying, binary frequency shift keying modulation schemes are derived and results are corroborated with the Monte-Carlo simulations and asymptotic analysis.

In this letter a new detection scheme combining the conventional Sphere decoders and best detection algorithm is proposed. This algorithm leverages the Sphere decoder (SD) results to use smaller values of in best algorithm to achieve better performance. Post best detection algorithm Darlington pairs of SD- SD, SD- SD, and -1 SD are used to get the final detection results. The proposed best detection algorithm finds out smallest paths by counting and sorting the bits of every candidate, which is much simpler as used in conventional sphere decoders. The computational complexity has been calculated in terms of time taken to visit the average number of K paths taken by Conventional SDs -SDs and Darlington pair of SDs. Extensive Monte Carlo simulations are used to demonstrate that the proposed approach exhibits significant performance gain over conventional SD schemes in terms of bit error rate and computational time. Besides, a complete analytical approach is provided to validate the simulation results.

In the centralized architecture of traditional mobile cellular network, every traffic of mobile terminals has to traverse the centered network core and then deliver to the corresponding service mobile terminals. Since the traffic load is concentrated on the central network core, it is difficult to deliver the explosive amount of network traffic and guarantee latency requirements of diversifying applications. In order to solve this problem, the mobile edge computing (MEC) architecture that distributes the traffic load by locating the computing and caching server closer to the terminal is currently being developed. In this paper, the effect of distribution of mobile traffic with MEC is evaluated in terms of throughput enhancements and latency reduction. The simulations were conducted using Mininet to determine what performance gains can be obtained when applying the MEC architecture to the mobile cellular network. As a result, under the same link bandwidth condition, MEC architecture provides an increase in data rates of approximately 265% for high-quality video transmission and about 162% for low-quality video transmission, and shows the reduced delay of packet arrival times.

Filter Bank Multicarrier with Offset Quadrature Amplitude Modulation (FBMC/OQAM) is one of the best waveforms used in 5G communications. The FBMC is a multicarrier modulation system (MCM) which suffers from high peak to average power ratio (PAPR) causing a reduction in power efficiency. Nonlinear companding techniques are widely used to reduce the peak-to-average-power ratio (PAPR). In this paper, we have evaluated the performance of different non-linear companding techniques to reduce the PAPR in FBMC/OQAM system while achieving good Bit Error rate. We assessed the hyperbolic tangent, the error function, the logarithmic function, the A-law, and Mu-law companding techniques. It is found that the best companding function is the Mu-law.

A secure stream cipher is an effective security solution for applications running on resource-constrained devices. The Grain family of stream ciphers (Grain v1, Grain-128, and Grain-128a) is a family of stream ciphers designed for low-end devices. Similarly, Espresso is a lightweight stream cipher that was developed recently for 5G wireless mobile communication. The randomness of the keystream produced by a stream cipher is a good indicator of its security strength. In this study, we have analyzed the randomness properties of the keystreams produced by both the Grain Family and Espresso ciphers using the statistical packages DieHarder and NIST STS. We also analyzed their performances in two constrained devices (ATmega328P and ESP8266) based on three attainable parameters, namely computation time, memory, and power consumption.

Blockchain, often integrated with distributed systems and security enhancements, has significant potential in various industries. However, environmental concerns and the efficiency of consortia-controlled permissioned networks remain critical issues. We use a Stochastic Petri Net model to analyze transaction flows in Hyperledger Fabric networks, achieving a 95% confidence interval for response times. This model enables administrators to assess the impact of system changes on resource utilization. Sensitivity analysis reveals major factors influencing response times and throughput. Our case studies demonstrate that block size can alter throughput and response times by up to 200%, underscoring the need for performance optimization with resource efficiency.

The production performance of multiparous lactating Sahiwal cows (n = 24) was evaluated according to bothmilking frequency and method. Selected animals were randomly divided into four groups containing six animalseach under a completely randomized design. Cows in groups A & B were milked by the hand milking methodthree times per day, respectively. Similarly, cows in groups C & D were milked by the machine milking method twoand three times per day, respectively. All animals were maintained under uniform feeding and managementconditions. Dry matter intake was high in animal groups milked three times per day, and it remained unchangedbetween the hand and machine milking methods. Milk yield was higher (P < 0.05) in cows milked three timescompared to those milked twice per day, and it did not differ between hand and machine milking methods. Milkfat percentage was higher (P < 0.05) in cows milked twice per day compared to those milked three times usingboth machine and hand milking methods. The percentage of total solids showed a similar pattern as the fatpercentage. However, percentages of protein, lactose, and non-fat solids in milk were not significantly different(P > 0.05) among the treatment groups. Collectively, the results show that milking three times per day instead oftwice at 8-hour intervals can enhance milk yield in Sahiwal cows using both hand and machine milking methods.

The purpose of this study was to assess the optimal standardized ileal digestible (SID) lysine (Lys) requirement for male White Pekin ducklings with a specific focus on growth performance for the 3 weeks following hatching. A total of 384 one-day-old male White Pekin ducklings were allocated to six different dietary treatments, each containing varying levels of digestible Lys content ranging from 0.72% to 1.12%. All amino acids in the diets remained consistent except for Lys. The ducklings were randomly distributed into 24-floor pens, with each treatment group comprising eight pens, and each pen housing eight ducklings. The diets were offered ad-libitum throughout the study. Weekly measurements of body weight and feed intake were recorded to calculate the feed conversion ratio. The SID Lys requirement was determined by analyzing the data using both linear-plateau and quadratic-plateau models and calculating the mean value. The results demonstrated a significant linear (p < 0.001) and quadratic (p < 0.001) improvement in body weight gain and feed efficiency with increasing SID Lys content in the diet. According to the linear-plateau regression analysis, the estimated SID Lys requirements for final body weight, weight gain, and feed efficiency were 1.00%, 1.00%, and 0.98%, respectively. Conversely, the quadratic-plateau regression analysis yielded estimated SID Lys requirements of 1.11%, 1.11%, and 1.10%, respectively, for the same parameters. In summary, this study established that the recommended SID Lys levels for White Pekin ducklings for the 3 wk period after hatching were found to be 1.05%, 1.05%, and 1.04% for achieving the finest final body weight, daily gain, and feed efficiency, respectively.

The study evaluated different molt-inducing methods to achieve the main goal of molting in commercial layers during molting and post-molting periods. A total of 400 60-week-old Lohmann Brown layers were randomly divided into five groups (eight replicates of 10 birds for each group). Laying hens in the fasting control group received no diet from day 1 to day 10. The second group received a molt-inducing diet recommended by the breeding company. The third group received a wheat bran-based diet. The fourth group received a commercial layer diet with 8,000 ppm zinc (as zinc oxide, ZnO). The fifth group received an induced molting diet given to the second group with 8,000 ppm zinc, respectively. Egg production in the fasting control group and groups fed a diet with ZnO were significantly lower (p < 0.001) than those in groups fed the molt-inducing and wheat bran-based diets without ZnO during molting. Egg laying in the fasting control group was rapidly reduced and stopped on the 5.9th day of molting. In both groups having molt treatment with ZnO, egg production was similarly reduced and ceased on the 6.9th day and 7.0th day of molting, respectively, none of them differed significantly from the control. Layers fed molt-inducing diet or wheat bran-based diet did not reach the cessation of laying even on the 28th d of molting period. Relative weights of the ovary and growing oocytes of layers subjected to fasting or fed diets with ZnO were significantly lower than those of other groups. During the first two weeks of post molting, layers fed molt-inducing diet with ZnO showed higher egg production than the other two groups (p < 0.01). The eggshell strength in the group fed the commercial diet with ZnO was significantly higher than those fed the molt-inducing diet or wheat bran-based diets at 6 weeks of post molting (p < 0.05). These results suggest that the non-feed withdrawal molting using ZnO is more effective in inducing molting and increasing post-molt egg production and egg quality than other methods using a molt-inducing diet alone or wheat bran-based diet without ZnO.

Two experiments were conducted to determine apparent metabolizable energy (AME), nitrogen- corrected AME (AMEn), and ileal digestible amino acid (AA) content of brown rice (BR) and to investigate the effect of dietary supplementation of BR on laying performance and egg quality of laying hens. In Exp. 1, 72 Hy-line Brown layers (49-week-old) were allocated to two treatments using a completely randomized block design, and each treatment included six cages per treatment and six hens per cage. A semi-purified diet was formulated to include BR as the sole source of AA and energy and an N-free diet was used to determine basal endogenous loss of AA. The hens were fed a commercial layer diet for adaptation to the experimental environment and diet for 7 days from d 0, and then fed experimental diets for 5 days from d 7. Excreta were collected from d 10 to 11 and ileal digesta were collected on d 12. On a dry matter (DM) basis, the AME and AMEn of BR was determined at 3,773 and 3,729 kcal/kg, respectively. The apparent ileal digestibility (AID) of BR ranged from 32.7% for Thr to 73.7% for Arg. The range of the standardized ileal digestibility (SID) value was between 79.4% for Met and 96.6% for Lys. In Exp. 2, 252 Hy-line Brown layers (44-week-old) were divided into four groups, comprising seven replicates of nine birds each and assigned to four experimental diets containing 0 (Control), 5%, 10%, or 15% BR for 5 weeks. The BR-containing diets were formulated to be equal in the content of AMEn and digestible AA to those of the diet without BR. No significant differences were observed in laying performances. Egg quality and blood profiles were not linearly or quadratically affected by dietary treatments. These results suggest that up to 15% BR can be included into layer feed without any adverse effects on laying performance and egg quality, if its energy and digestible AA values are well evaluated.

Purpose: To develop a tool for measuring peripheral intravenous catheter insertion performance. Methods: This was a cross-sectional descriptive study. Initial items were generated using existing guidelines and tools, and 19 experts assessed content validity. Data were collected from a tertiary hospital in D city from January 17, 2018, to October 20, 2019. The data of 365 nurses were used for principal component analysis with orthogonal rotation. Concurrent validity was confirmed using Pearson’s correlation between the developed tool and the nursing career period. Reliability was confirmed after evaluating internal consistency. Results: Initially, 16 items were generated, but three items were deleted in content validation. A two-factor solution was preferred in exploratory factor analysis and explained 48.2% of the variance. The two factors were named “point of care” and “follow-up care,” respectively. The tool’s reliability is .87. Conclusion: The developed tool was valid and reliable. It is composed of 13 items and can be used quickly and easily. Therefore, it can be utilized for the education and training of novice nurses and the self-reflection of experienced nurses. In addition, it will be useful to review the catheterization process in common clinical settings.

본 논문은 주관적 성과평가(subjective performance evaluation) 과정에서 평가 척도 점 수를 부여할 때 발생할 수 있는 평가자의 관대화 경향이 전년도 성과 정보에 영향을 받는가 에 대해 분석한다. 성과평가와 관련한 선행연구가 객관적 성과지표 점수 또는 척도 점수의 중간 값을 관대화 경향의 기준점(benchmark)으로 이용하고, 횡단면 연구(cross-sectional research)에 국한되었기 때문에 관대화 경향의 지속성 여부 및 전년도 성과 정보의 당해 년 도 관대화 경향에의 영향을 분석하는 데에는 한계가 있었다. 본 연구에서는 당해 년도 성과 점수와 상관관계가 높은 전년도 성과 점수를 기본으로 한 기준점을 바탕으로 관대화 경향을 계측한다. 이와 같이 새로 개발된 관대화 경향 변수를 바탕으로 (1) 관대화 경향이 시간이 지 나도 지속되고, (2) 전년도에 성과점수가 낮고(높고), 덜(더) 관대하게 평가 받은 피평가자에 대해 당해 년도에는 관대화 경향이 크다(작다)는 실증 분석 결과를 제시한다. 이와 같은 결과 는 평가자의 인센티브가 전년도 성과 정보에 따라 좌우될 수 있고, 그 경향이 지속된다는 점을 시사한다.

This paper examines whether supervisors’ leniency in subjective performance evaluation is influenced by the prior performance information of subordinates. While prior studies have used proxies for leniency based on aggregate objective performance level or median of subjective scales, I develop the proxy for leniency at the performance measure level based on prior performance level which is found to be more relevant to the current subjective performance score. I analyze archival performance evaluation data of multiple state-owned enterprises (SOEs) in Korea over multiple time periods which enables me to develop the new definition of leniency. Utilizing this data set, I empirically find that lenient rating persists over time, and that larger (smaller) amount of leniency is applied to low (high) prior performers and harshly (leniently) evaluated performers in the previous period. The results have important implications for understanding the incentives of raters which differ with respect to their previous performance information.

This paper shows how the fund performance evaluation system influences the fund market and fund family behaviors. Evaluation-ship Bias is defined as the outperforming of evaluated funds over non-evaluated funds. Regarding the Evaluationship Bias, this study confirmed two things in empirical analysis of Korean equity funds. First, this paper verified that there was Evaluation-ship Bias in Korea, so fund families’ performances were over-estimated. Second, it is also found that fund families did favoritism to evaluated funds in management activities. Fund families were more attentive to EV performance and took strategic and risk-taking measures to improve its ratings. This paper suggests that another factor, the performance evaluation system itself, is what causes fund families to favor some funds. The existence of too high numbers of Korean funds is an example of this evaluation system bias. We can expect similar phenomena to occur in other countries as well. We also suggest that the introduction of GIPS will diminish the evaluation system bias and contribute to the development of the Korean fund market.

The development of the Internet of Things (IoT) has created new issues in network security due to the diverse resource-constrained nature of IoT devices and the massive volume of generated heterogeneous data. One of the most important procedures in network security is intrusion detection system (IDS). The goal of intrusion detection is to locate and stop harmful activity within the network. Machine learning methods are employed to create precise IDS models. This article provides a practical overview of tree-based Machine Learning (ML) algorithms for intrusion detection. It delves into the application of Random Forest (RF), Decision Tree (DT), AdaBoost, and the J48 classifier in the context of network traffic security. The NSL-KDD data set is used to evaluate these approaches. According to experimental results, the Random Forest Classifier outperforms the other techniques.

In this paper, by cross-applying the DINO (DETR with Improved deNoising anchOrboxes) model to various datasets, we examine what characteristics of dataset are effective for traffic object detection training. DINO model is best DETR (DEtection with TRansformer)-like model in object detection. For the experiment, a total of two datasets were used: COCO and BDD100K datasets. As a result of evaluation with BDD100K dataset which contains diverse driving images, dataset with the same texture as the evaluation dataset showed similar performance with less data than the high texture dataset focused on each object.

The mechanical properties of REBCO coated conductor (CC) tapes under uniaxial tension are mainly determined by the thick layer components like the substrate and the stabilizer. Depending on the applications of the CC tapes, it is also needed to externally reinforce thin metallic foils to one side or both sides of the CC tapes. This study investigated the effect of additional stabilizer layers or lamination on the electrical resistivity and electromechanical properties in RCE-DR processed GdBCO CC tapes with different structures. The strain/stress tolerance of Ic in differently processed 12 mm-wide REBCO CC tapes under uniaxial tension at 77 K and self-field could be determined by the loading-unloading scheme. As a result, Sn-Cu stabilized CC tape showed a significant decrease in mechanical properties due to its soft but thick stabilizing layer. However, similar electromechanical properties have been observed on both Sn-Cu and Snstabilized CC tapes, the Ic degradation behavior was independent of whether the CC tape has an external reinforcement or different stabilizing layers.